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Armtrac 100 Trial Report

This document is subject to the release conditions printed on the reverse of this page

Cover + xii + 88 pages April 2002

QINETIQ/FST/CRMV/CR022665

C.A.LEACH


ii

Customer Information

Customer Reference Number CNTR 98 4558 Project Title Armtrac 100 Trial Report Company Name DFID Customer Contact Mr A Willson Contract Number 183660 0002 Milestone Number N/A

© Copyright of QinetiQ ltd 2002 Approval for wider use of releases must be sought from:

Intellectual Property Department, QinetiQ ltd, Cody Technology Park, Farnborough, Hampshire GU14 0LX

This document is released to DFID for limited purposes only, and is not to be used for other purposes or disclosed to any third party without QinetiQ consent


iii

Authorisation

Prepared by Mr C A Leach Title Research Engineer Signature

Date 18th April 2002 Location QinetiQ Pyestock

Authorised by Mr D Lewis Title Project Manager Signature

Date Principal authors Name Mr P W Blatchford Appointment Research Engineer Location QinetiQ Pystock

Name Mr C A Leach Appointment Research Engineer Location QinetiQ Pyestock


iv

Record of changes

Issue Date Detail of Changes A 3/4/2002 Draft

1.0 19/4/2002 Initial Issue


v

Abstract

This report is a technical assessment of the Armtrac 100 Mine Flail. The equipment consists of a flail unit with cowling attached to an armoured agricultural tractor.

The trial was carried out after QinetiQ staff underook a pre-trial assessment of the vehicle for the Department For International Development (DFID).

The report concludes that the Armtrac 100 Mine Flail is a well designed and capable machine. It demonstrated an ability to clear anti-personnel sized mines from terrain ranging from sandy topsoil to gravel track and heavy clay, but with limitations on clearance depth. It also concludes that the Armtrac 100 has good vegetation clearance ability and good mobility. The machine survived a limited range of live explosive tests, although these did not fully assess the safety of the operator.

Overall, the objectives of the trial were achieved by demonstrating the concept of using a flail to clear mines and dense foliage from various terrains. As with most mechanical clearance processes the application of this equipment has to be in the context of the mine threat, type of terrain, climatic and environmental conditions and of the overall demining operation.


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Executive summary

This report describes the results of an assessment of the Armtrac 100 flail carried out by QinetiQ on behalf of the Department For International Development (DFID). Using contacts through ITEP (International Test and Evaluation Programme), engineers from UK, Sweden, European Commission and Canada participated in the trial, bringing a wide range of expertise and techniques to the tests.

The trial set out to test the Armtrac 100 under the four main categories of:

• Transportability • Mobility • Performance • Survivability

During the trial the Armtrac 100 proved to be a capable and well engineered machine. It proved to have a good level of mobility due to being based on an all wheel drive agricultural tractor and has good manoeuvrability for a vehicle of its size. It is easily transportable on the back of a low-loader, and the flail unit can be removed.

Armtrac 100 showed a good ability as a brush and vegetation clearer with the capability to reduce medium to heavy density foliage to fine mulch. Its only main limitation in this role was operating on terrain with a rapidly changing gradient.

The machine demonstrated a good ability to clear mines under the conditions tested, but with limitations on clearance depth. As with most machines of this nature, it demonstrated the potential to break up mines without detonating them and throw components containing live explosive into previously cleared areas.

During the survivability section of the trial, the Armtrac 100 showed good survivability against frontal attack from plastic explosive charges of up to 7kg, remaining fully functional throughout with only minor damage sustained. However the testing was limited to certain parts of the machine only (particularly the flail header) against a limited range of threats and was not exhaustive in assessing overall vehicle survivability or operator safety.

This piece of equipment has the potential to be a valuable asset for assisting mine clearance operations when used in the right environment and under appropriate circumstances. However reference should be made to the Conclusions section of this report where the limitations of the machine and the testing carried out on it are discussed in more detail.


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List of contents

Authorisation iii

Record of changes iv

Abstract v

Executive Summary vi

List of Tables ix

List of Figures x

1 Introduction 1 1.1 Contractual Matters 1 1.2 Background 1 1.3 Objective 1

2 Equipment used during trial 2 2.1 Armtrac 100 2 2.2 Facilities 2 2.3 Mine Threat 3 2.4 Soil Cone Penetrometer 4

3 Trials Methodology 6 3.1 General 6 3.2 Phase 1- Transportability, Mobility and Performance 6 3.3 Phase 2 -Survivability 6 3.4 Sites 6

4 Test Procedures 8

5 Results 9 5.1 Transportability and general dimensions 9 5.2 Handling and Mobility 14 5.3 Logistics and Daily Maintenance 27 5.4 Performance 29 5.5 Survivability against mine attack 50

6 Conclusions 73 6.1 Transportability 73 6.2 Mobility 73 6.3 Performance 74


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6.4 Survivability 75

7 Recommendations 77 7.1 Armtrac 100 77 7.2 Trial Methodology 78

8 Acknowledgements 79

9 References 80

10 Appendix - Pre-Trial Report for Armtrac 100 81

Distribution list 85

Report documentation page 87


ix

List of Tables

Table 2-1 Inert mines used 3 Table 2-2 Live mines used 3 Table 4-1 Summary of Tests 8 Table 5-1 Dimensions of Armtrac 100 9 Table 5-2 Armtrac 100 weights 10 Table 5-3 Tilt table results 11 Table 5-4 Turning circle of Armtrac 100 14 Table 5-5 Results of the slope test 16 Table 5-6 Speed statistics for Armtrac 100 22 Table 5-7 Results of mobility tests 24 Table 5-8 Log of hours and maintenance 27 Table 5-9 Mine data for obstacle clearance course 33 Table 5-10 Details of vegetation cleared 36 Table 5-11 Summary of inert minefield encounter 43 Table 5-12 Start & finish positions for Field 1,Lane1 45 Table 5-13 Start & finish positions for Field 1,Lane2 46 Table 5-14 Start & finish positions for Field 2,Lane1 47 Table 5-15 Start & finish positions for Field 2,Lane2 48 Table 5-16 Start & finish positions for Field 3,Lane1 49 Table 5-17 Start & finish positions for Field 3,Lane2 49 Table 6-1 Summary of MRM clearance performance 74


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List of Figures

Figure 2-1 Armtrac 100 2 Figure 2-2 Soil cone penetrometer 4 Figure 2-3 Soil strength being measured with penetrometer 5 Figure 5-1 Dimensions of Armtrac 100 9 Figure 5-2 Armtrac 100 on the Weighbridge 10 Figure 5-3 Side tilt test 12 Figure 5-4 Nose down tilt test 12 Figure 5-5 Centre of gravity of Armtrac 100 with flail raised 13 Figure 5-6 Centre of gravity of Armtrac 100 with flail at working height 13 Figure 5-7 Turning circle of Armtrac 100 14 Figure 5-8 Tracks made whilst measuring Turning Circle 15 Figure 5 -9 Armtrac 100 climbing 40% tarmac slope 17 Figure 5-10 Armtrac 100 climbing 35% off-road slope 17 Figure 5-11 Vision diagram of Armtrac 100 with flail header down 18 Figure 5-12 Vision diagram of Armtrac 100 with flail header up 19 Figure 5 -13 View through front window in driving mode (flail header down) 20 Figure 5-14 View through front right-hand side window 20 Figure 5-15 View through rear right-hand side window 21 Figure 5-16 View through rear window 21 Figure 5-17 Armtrac 100 driving over cresting slope (from left to right) 23 Figure 5-18 Armtrac 100 at apex of cresting slope 23 Figure 5-19 Off road slopes 24 Figure 5-20 Test mine before burial 26 Figure 5-21 Buried mine about to be driven over 26 Figure 5 -22 GSCS mechanic carrying out checks to the flail header 28 Figure 5-23 GSCS mechanic carrying out checks to the power take off 28 Figure 5-24 Ridges found at the base of the cut 30 Figure 5-25 Line of peat mines at 200mm depth before flailing 30 Figure 5-26 Line of peat mines at 200mm depth uncovered after flailing 31 Figure 5-27 Layout of test runs 32 Figure 5-28 Obstacle clearance course 33 Figure 5-29 Rock obstacle before 34 Figure 5-30 Rock obstacle after 34 Figure 5-31 Armtrac100 flailing log obstacle 35 Figure 5-32 Bracken before flailing 37 Figure 5-33 Bracken after flailing 37 Figure 5-34 Line of shrubs before flailing 38 Figure 5-35 Line of shrubs after flailing 38 Figure 5-36 140mm Silver Birch tree 39 Figure 5-37 Silver Birch after flailing 39 Figure 5-38 Armtrac clearing bank 40 Figure 5-39 Inert minefield layouts 42 Figure 5-40 Ridges of unflailed soil in field 3 44 Figure 5-41 Plan view of flail header for 1st firing 50 Figure 5-42 Location of charge 1 51 Figure 5-43 Front view of flail header for 2nd firing 52 Figure 5-44 Front view of the flail header with charge in place 53 Figure 5-45 Front view of the flail header with charge detonating 53 Figure 5-46 Hole in the flail blast plate 54 Figure 5-47 Plan view of flail header for 3rd firing 55


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Figure 5-48 Location of charge 3 56 Figure 5-49 Damage to rubber flaps 56 Figure 5-50 Plan view of flail header for 4th firing 57 Figure 5-51 Location of charge 4 58 Figure 5-52 Front view of the flail header with charge detonating 58 Figure 5-53 Plan view of flail header for 5th firing 59 Figure 5-54 Location of charge 5 60 Figure 5-55 Plan view of the flail header for fragmentation mines 61 Figure 5-56 Front view of the flail header with fragmentation mine 62 Figure 5-57 Front view of the flail header with fragmentation mine detonating 62 Figure 5-58 Side view of the flail header with second fragmentation mine 63 Figure 5-59 Side of flail support arm after second fragmentation mine firing 63 Figure 5-60 Plan view of flail header for first AT firing 64 Figure 5-61 Location of first AT charge 65 Figure 5-62 Distribution of cowling doors after 5.5Kg AT blast 66 Figure 5-63 Flail cowling after first AT blast 66 Figure 5-64 Distorted flail unit mounting 67 Figure 5-65 Flail drive chain cover - showed sheared bolt head 67 Figure 5-66 Plan view of flail header for second AT firing 68 Figure 5-67 Location of second AT charge 68 Figure 5-68 Distribution of cowling doors after 7Kg AT blast 69 Figure 5-69 Final position of one of the cowling doors 70 Figure 5-70 Flail cowling after second AT blast 70 Figure 5-71 Gearbox guard plate touching steering link arm 71 Figure 5-72 Distorted chassis rail 71 Figure 5-73 Cracked weld in flail cowling support arm 72


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Page 1 of 88

1 Introduction

1.1 Contractual Matters

The Humanitarian Demining team at QinetiQ has produced this report for the Conflict and Humanitarian Affairs Department (CHAD) at The Department for International Development (DFID) of the UK government.

Authority by DFID to undertake the trial was given in January 2002 under enabling agreement CNTR 98 4558.

A Trial Plan [1] & Safety Plan [2] were submitted to DFID and all those persons who were to attend the trial.

1.2 Background

Armtrac 100 is manufactured by Ground Sift and Clear Systems (GSCS) of Cambridge, UK, along with two other machines: Armtrac 75 and Armtrac 325. The machine under test was owned by G3 Systems, a UK defence contractor.

QinetiQ was tasked by DFID to carry out a pre-trial assessment and, pending the results, a full trial of the Armtrac 100. [Appendix A]

The Armtrac 100 comprises a flail header mounted to the front power take off (PTO) of an armoured agricultural tractor. The flail has an extended blast plate that has spring-loaded plates at the top. These spring-loaded plates are designed to prevent debris from being thrown over a wide area during flailing and to open to allow the blast from an explosion to vent thus minimising damage to the vehicle.

1.3 Objective

Aim

The aim of the trial was to test and evaluate the transportability, mobility, performance and survivability of the Armtrac 100 flail system under defined threat and terrain conditions. The trial set out to prove the concept of this system under repeatable scientific conditions not to replicate any specific field conditions.

Scope

The equipment was evaluated on its performance and its ability to clear representative AT mines, AP mines and other battlefield debris. Tests included transportability and manoeuvrability across flat, uphill, downhill and cross-country terrain. For some of these tests, inert mines were buried flush to or beneath the surface. The survivability of the flail unit was tested against live AP blast and fragmentation mines and AT blast mines. The survivability tests that were carried out draw conclusions on the survivability of certain parts of the machine only (and more specifically the flail header), against a limited range of threats. Further testing will be required to provide a more thorough assessment of the overall vehicle survivability and particularly operator safety.


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2 Equipment used during trial

2.1 Armtrac 100

The Armtrac 100 is based on a New Holland agricultural tractor with a flail unit attached to the front PTO (Power Take Off). GSCS remove the cab and the non-structural body parts from the tractors and replace them with armour plate. The driver’s cab is rebuilt with armour plate, toughened glass (45mm polycarbonate/glass laminate) and additional strengthening to the seat and driver’s harness.

As mentioned above, the flail unit is run from the front PTO making it easily interchangeable with either a Milling Drum or Runway Clearance Device. Unfortunately, the Milling Drum and Runway Clearance Device were unavailable for testing at the time of the trial.

The Armtrac 100 is based on an agricultural device and is registered as such so that it can be used for non-demining activities as well. GSCS currently has machines deployed in Bosnia and Mozambique.

Figure 2-1 Armtrac 100

2.2 Facilities

The following facilities were used at the QinetiQ Hurn Test Facility:

• Tilt Table • Weighbridge • Concentric circles for vision test • Graduated slopes • Cresting ramp


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2.3 Mine Threat

Four different types of mine simulant were used:

• MRM’s – Mechanical Reproduction Mines are made by Amtec Aeronautical Ltd of Canada and are the same size, shape and weight as the mine they seek to represent. The trigger mechanism is also very similar to the real mine but has no explosive content and when triggered breaks an identifying antenna coil. The coil enables untriggered mines to be located and identified with a hand-held detector. PMN and PMA-2 MRM’s were used in this trial.

• Peat mines – These are solid cylindrical shaped targets (Ø60mm x 40mm) made from compressed peat. Although they do not represent a specific mine in shape, size and have no trigger mechanism, they can be used as a ‘witness’ in a trial such as this. These simulants disintegrate under direct impact so conclusions can only be drawn if the simulants are found whole and intact either where they were placed or in the spoil left after flailing.

• Wax or concrete filled plastic cases – these are designed to represent a specific mine in shape, size and weight. Although they have no trigger mechanism, they can also be used as a ‘witness’ in a trial such as this. TMA-2, TMA-3, TMA-4, TMA-5 and TMRP-6 cases were used.

• Solid metal mine simulant - These are designed to represent a specific mine in shape, size and weight. Although they have no trigger mechanism, they can also be used as a ‘witness’ in a trial such as this. These were found to be of limited use in this trial so only two ‘Minotaur’ scatterable mines simulant were used.

Type Depth buried Anti-Personnel Mines PMN MRM Flush, PMA-2 MRM 100mm to top Peat mine 200mm to top

Anti-Tank Mines Wax or concrete plastic

cases Surface,

Solid metal mine simulant 150mm to top 200mm to top

Table 2-1 Inert mines used

For the survivability trial, plastic explosive was used in quantities representative of AP blast and fragmentation mines and AT blast mines. These are shown below in Table 2-2.

Amounts of Plastic Explosive to represent blast AP mines

Anti-Personnel Mines

POMZ-2M with 100g PE (Fragmentation Mine) Plastic casing with 5.5kg PE Anti-Tank Mines Plastic casing with 7kg PE

Table 2-2 Live mines used


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2.4 Soil Cone Penetrometer

At various stages of the trial, it was considered useful to have an indication of the condition of the soil, particularly its strength. This is relevant when considering both the mobility of the vehicle and its flailing performance. A soil cone penetrometer was therefore used to provide a measure of soil strength.

The soil cone penetrometer used consisted of a steel cone with a base area of 0.5 in2 on the end of a thin steel shaft marked with graduations at 3 inch intervals, see Figure 2-2. At the top of the shaft was a handle and force gauge, indicating the force exerted on the cone. Its method of operation was to press the cone into the soil and note the force reading when the top of the cone was level with the soil surface and then as each graduation was level with the soil surface. The readings were given as ‘Cone Index’ (CI), being equal to twice the force in pounds i.e. CI 100 = 50lbs = 100lbs/in2 pressure.

The results obtained were therefore a series of numbers (usually 3 or 4) corresponding to the pressure required to drive the cone through the soil at subsequent 3 inch depth increments i.e. high readings indicate hard soil. The readings were often very variable, particularly in soft soil or where voids were encountered, so a number of readings had to be taken and averaged. It should be noted that the penetrometer manual states “Caution is necessary in interpreting readings taken in loose dry sand where immobilisations are mainly the result of traction failure.” Hence the readings recorded should be treated as a relative indication of soil strength, rather than an accurate repeatable measurement.

Figure 2-2 Soil cone penetrometer


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Figure 2-3 Soil strength being measured with penetrometer


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3 Trials Methodology

3.1 General

The trial was carried out and managed by the Humanitarian Demining trials team from QinetiQ with additional help from representatives of the following organisations:

• Chris Leach – QinetiQ, UK • Pete Blatchford – QinetiQ, UK • Geoff Coley – Canadian Centre for Mine Action Technologies (CCMAT), Canada • François Littmann – European Union Joint Research Centre (JRC) • Göran Danielsson – Swedish EOD and Demining Centre (SWEDEC), Sweden • Ola Modigs - Swedish Defence Materiel Administration (FMV), Sweden • Anders Gustafsson – FMV, Sweden

Details can be found in the Trial Plan. Results and observations were recorded daily and supported by still photography and video recordings. The trial was conducted in two phases:

3.2 Phase 1- Transportability, Mobility and Performance

Phase one included transportability, handling and mobility of the machine followed by an assessment of its performance.

The transportability tests assessed the factors involved in movement of equipment to and from the demining area. These include size and general dimensions, weight and ability to climb loading ramps.

The mobility tests included assessments of travelling speed, slope climbing ability, stability and general manoeuvrability.

The performance tests were split into three main areas:

• Fitness for purpose was assessed in conjunction with other tests and by encountering mine simulants and other objects in a series of inert minefields.

• Reliability was assessed on a day to day basis throughout the trial with notes taken of any maintenance required.

• Running costs were assessed by comparing the amount of consumables, such as fuel, used against the amount of work carried out by the machine.

3.3 Phase 2 -Survivability

The Armtrac 100 was subjected to static live mine encounters to determine the survivability of the flail unit against a limited range of representative threats.

3.4 Sites

Two sites were used for this trial: QinetiQ Hurn and QinetiQ Shoeburyness both in the south of England.


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3.4.1 QinetiQ Hurn / Sandleheath

The Hurn site consists of sandy topsoil with vegetation consisting of light grass with clumps of marsh grass, small shrubs and saplings. The site has purpose built test lanes varying from blacktop surfaces to sand with varying cambers, cross grooves and ditches and measured slopes and turning circles.

The nearby Sandleheath site consists of predominantly clay-based topsoil, which in parts has remained undisturbed for a number of years. The vegetation consists of light grass with clumps of marsh grass, small shrubs, saplings and larger trees.

Phase 1 of the trial was conducted at Hurn and Sandleheath, using the range of test lanes and slopes available to measure performance.

3.4.2 QinetiQ Shoeburyness

The QinetiQ Shoeburyness land area of New Ranges and Foulness Island has a total of 26 individual sites, each with a unique firing range for the dynamic or static activity to be conducted. Most of these areas extend over tenanted agricultural land that is evacuated daily as required. This includes the evacuation of farmsteads on occasions.

Shoeburyness was used for phase 2 of the trial, the static live explosive tests.


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4 Test Procedures

Test procedure and performance sheets were issued for each test. The test performance sheets have been retained by QinetiQ and are available on request.

A summary of the tests is shown in Table 4-1. A description, summary of results and comments/observations of each test are detailed on the following pages.

Test Description Transportability and general a) General Dimensions dimensions b) Weights c) Tilt Test Handling & Mobility a) Turning Circle b) Slopes c) Field Of Vision d) Timed Run & Flailing Speed e) Cresting Ramp f) Mobility Over Rough Terrain g) Ground Pressure Logistics/Daily Maintenance Performance a) Flail Pattern b) Test Run c) Obstacle Clearance d) Brush & Vegetation Clearance e) Inert Minefield Encounter Live Firing a) AP Blast b) AP Fragmentation c) AT Blast

Table 4-1 Summary of Tests


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5 Results

5.1 Transportability and general dimensions

5.1.1 General Dimensions

The following measurements were taken using a tape measure and a straight edge; the dimensions are given in metres and degrees:

Measurement Length/Angle Height 2.9m Overall length 6.85m Length of tractor unit 4.78m Wheelbase (Length between front & rear axles) 2.63m Width between the external faces of the wheels 1.96m Width of flail header 2.64m Width of cut made by flail 2.08m Ground clearance under front hitch of tractor 0.43m Ground clearance under belly of tractor 0.45m Approach angle 22.5º Departure angle 30.6º

Table 5-1 Dimensions of Armtrac 100

Figure 5-1 Dimensions of Armtrac 100


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5.1.2 Weights

The Armtrac 100 was driven onto the QinetiQ Hurn 50 tonne weighbridge. The gross vehicle weight was measured, then front and rear axle weights and individual wheelstation weights. All measurements were made with the driver in his seat, and were repeated with the flail unit at working height and fully raised.

The following results were obtained. All measurements are in kilograms.

Flail at working height Flail fully raised

Gross vehicle weight 11010 11010

Front axle weight 7280 7210

Rear axle weight 3730 3800

Front left wheelstation 3660 3620

Front right wheelstation 3690 3620

Rear left wheelstation 1830 1920

Rear right wheelstation 1700 1770

Table 5-2 Armtrac 100 weights

Figure 5-2 Armtrac 100 on the Weighbridge


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5.1.3 Tilt test

The Armtrac 100 was driven onto the QinetiQ Hurn 60 tonne tilt platform and secured with chains. Restraining blocks (150mm tall) were used to prevent the wheels sliding down the platform when tilted. Body roll clinometers were attached to the front and rear of the tractor body to measure any difference between the table inclination and body inclination (i.e. body roll). The angle at which the first wheel lifted was recorded. The vehicle was tilted both to the left and the right, and with the flail unit at working height and fully raised. The test was also repeated with the vehicle being tilted forwards (i.e. ‘nose down’), with the flail unit fully raised.

The following results were obtained. All angles in degrees

Flail at working height Flail fully raised

Right tilt Left tilt Right tilt Left tilt Nose down

Platform angle 21.3 19.5 20.2 19.1 50.9

Front body angle 26.8 22.4 26.3 22.4 *

Rear body angle 26.8 22.5 26.4 22.5 *

Maximum body roll 5.5 3.0 6.2 3.4 *

First wheel to lift Left rear Right rear Left rear Right rear Right rear

Table 5-3 Tilt table results

* Body angle measurements were not taken during the nose down tilt test.


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Figure 5-3 Side tilt test

Figure 5-4 Nose down tilt test


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5.1.4 Centre of Gravity

The weighbridge and tilt test results were combined to determine the approximate position of the centre of gravity of the vehicle, as shown below:

Figure 5-5 Centre of gravity of Armtrac 100 with flail raised

Figure 5-6 Centre of gravity of Armtrac 100 with flail at working height

1.72m 0.91m

1.50m

1.74m 0.89m

1.48m


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5.2 Handling and Mobility

5.2.1 Turning Circle

Armtrac was parked on a piece of level tarmac. The positions of the axles and the outermost corner of the flail were marked on the floor along with a line running perpendicular to the rear tyre. The machine was then required to turn through an angle of 180º using its maximum turning lock. The procedure was carried out for both left and right-hand turns. The Armtrac 100 also has individual braking on each of the rear wheels. An additional test was carried out to determine the effect that this would have on the turning circle.

The following results were obtained.

Figure 5-7 Turning circle of Armtrac 100

Direction ØA (metres) ØB (metres) Forward right-hand lock, unbraked 17.63 12.64 Forward left-hand lock, unbraked 17.09 12.23 Forward right-hand lock, braked 15.26 9.40 Forward left-hand lock, braked 13.87 8.8 Full circle right-hand lock, braked 11.09

Table 5-4 Turning circle of Armtrac 100


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Figure 5-8 Tracks made whilst measuring Turning Circle


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5.2.2 Slopes

The Armtrac 100 was required to drive up various tarmac slopes of known gradient, come to a complete stop halfway up the slope and then continue to the top of slope. The procedure was then repeated for the machine descending the slope, and both ascending and descending in reverse.


Gradient Terrain Result

24.5% Stop & Restart Tarmac Satisfactory up & down slope, forward and reverse, brakes OK

31% Stop & Restart Tarmac Satisfactory up & down slope, forward and reverse, brakes OK

40% Stop & Restart Tarmac Satisfactory up & down slope, forward and reverse, brakes OK

35% Continuous run Loamy Soil, light vegetation (Off-road)

Lost traction three quarters of the way up due to uneven ground.

Table 5-5 Results of the slope test


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Figure 5 -9 Armtrac 100 climbing 40% tarmac slope

Figure 5-10 Armtrac 100 climbing 35% off-road slope


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5.2.3 Field of vision

The aim of this test was to assess all round driver visibility. The vehicle was positioned on a flat area of ground with concentric circles marked out, centred on the driver’s seat. The view from the driver’s seat was plotted with the flail at working height and raised to driving height.

The vision diagrams are reproduced in Figure 5-11 and Figure 5-12. In the diagrams white represents clear vision and shaded area represents no vision. It was noted that the cowling and the air scrubbers on the front of the machine limited vision. The vision to the sides and rear was restricted by the cab structure – however most of these areas could be seen by the driver adjusting position in his seat.

Figure 5-11 Vision diagram of Armtrac 100 with flail header down


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Figure 5-12 Vision diagram of Armtrac 100 with flail header up


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Figure 5 -13 View through front window in driving mode (flail header down)

Figure 5-14 View through front right-hand side window


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Figure 5-15 View through rear right-hand side window

Figure 5-16 View through rear window


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5.2.4 Timed run and flailing speed

From a rolling start the machine was timed over a 400m run on a flat and level tarmac surface. On the full speed run the machine was driven at the maximum safe speed. On the cruising speed run the machine was driven at a speed which was representative of the normal speed used in driving to and from clearance areas. Timings of flailing runs were also taken (over 12 metres).


Mode Time (seconds) Average Speed (kph) Full Speed 28 51 (14m/s) Cruising Speed 41 35 (9.75m/s) Flailing Speed Loamy, sandy soil: 112 0.39 (0.11 m/s) Gravel track: 111 0.39 (0.11 m/s)

Table 5-6 Speed statistics for Armtrac 100

5.2.5 Cresting Ramp

The cresting ramps and fixed loading ramps are designed to highlight problems with excessive overhang or restricted underbelly clearance encountered on loading ramps and other scenarios where there is a sharp change in gradient.

Due to time constraints the machine was only tested on the 24% cresting ramp. A sketch can be seen in Figure 5-17. On the forward run, the base of the flail header grounded against the slope and the machine could proceed no further. This was expected and highlighted the importance of the measurement of approach angle (22.5º).

The run was then conducted with the machine driving in reverse. The flail header grounded again but because it was being pulled and not pushed it did not dig in and cleared the ramp and descended down the other way (see Figure 5-18).


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Figure 5-17 Armtrac 100 driving over cresting slope (from left to right)

Figure 5-18 Armtrac 100 at apex of cresting slope


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5.2.6 Mobility Over Rough Terrain

The aim of the test was to determine the Armtrac 100’s mobility over steep off-road terrain. This aspect of mobility was also assessed during the other tests.

An area of rough ground was identified, the gradient and the soil strength were measured. The soil was a soft sandy loamy mix. Armtrac 100 was required to drive up the shallower of the two test lanes, reverse back down and repeat with the steeper slope. It was stated by GSCS that as part of the SOP’s the machine would probably use the flail to level any steep banks it was required to travel over thus reducing the severity of the gradient. With this in mind Armtrac 100 was allowed to use its flail if it lost traction on the slope. The slopes used are shown in Figure 5-19.

The following results were obtained. See also section 5.4.4 for a similar test carried out on different terrain.

Test Lane Soil Penetrometer Reading Gradient Comments Shallow

15,35,30,30,40 14º Completed test adequately

Extreme 15,35,30,30,40 30º Lost traction at several points

Table 5-7 Results of mobility tests

Figure 5-19 Off road slopes


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5.2.7 Ground Pressure

The pressure exerted on the ground by an off-road vehicle is an important factor when considering its mobility. However there is no simple measurement that can be made in order to assess this, as mobility and traction are dependent not only on the tyre footprint and load, but on the tyre tread, its change in footprint with load and sinkage, the soil strength at different depths and other factors. However for a mine clearing vehicle, ground pressure also has an important bearing on the likelihood of the vehicle detonating mines by driving over them.

A series of tests were therefore conducted to determine whether the Armtrac 100 was likely to detonate AP mines by driving over them. Although the tyres were within the flailing width, it would be possible for mines to be missed by the flail (for example through insufficient depth of flailing) and hence pass under the wheels. The considerable weight on the front axle, combined with small tyres (compared with the rears) will result in a high ground pressure under the front wheels.

5 PMN MRMs were each buried 20cm deep, in a line with 5m between each mine. A front wheel of the Armtrac 100 was then driven over each one in turn, and the mines carefully dug up and checked for triggering. Each one was triggered.

The test was therefore repeated with the mines buried at 30cm, and again each one was triggered. Finally it was repeated with the mines buried at 45cm and again each one was triggered. As a check that the burying or excavating operations were not triggering the mines, one mine was buried and then dug up without being driven over. It was not triggered.

With each burial, a second hole was dug and filled back in so that a soil cone penetrometer measurement could be taken in the disturbed soil. Readings were also taken in nearby undisturbed soil (see . The following (averaged) results were obtained :

Undisturbed soil : 26,132,218

Disturbed soil : 8,22,12,14

Clearly the soil in which the mines were buried was a lot less compacted than the surrounding soil, which may have had a bearing on the triggering of the mines. However the holes were dug as narrow as possible, so the surrounding soil will have provided considerable support to the wheel, rather than allowing all the load to be carried by the softer soil above the mines – see Figure 5-20 and Figure 5-21.

The conclusion drawn from this test is that the Armtrac 100 appears likely to trigger AP mines that it drives over.


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Figure 5-20 Test mine before burial

Figure 5-21 Buried mine about to be driven over


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5.3 Logistics and Daily Maintenance

The aim was to assess the service routine by considering the amount of maintenance and consumables needed in the day to day running of the Armtrac 100.


Date Hours Logged

Consumables Comments

25 Feb 2.8 None • Oil & water levels checked daily.

26 Feb 0.5 • Oil & water levels checked daily. • 250-hour check of flail drive chain tension.

27 Feb 1 Grease • Oil & water levels checked daily. • 10-hour service:

• Header bearings & drive shafts, hydraulic ram pivots, front trunnion pin & swivel jobs, drag link and lift arms greased.

• Clutch inspected. • Radiator, air cleaner and monoclone pods

cleaned with compressed air. • Total time to service: 2 men for ½ hour

28 Feb 1.6 • Oil & water levels checked daily. • Lost 1 hammer from chain end.

1 Mar 1 • Oil & water levels checked daily. 4 Mar 1.7 • Oil & water levels checked daily. 5 Mar 1.2 • Oil & water levels checked daily.

• Loading time: 1.5 minutes plus 8 minutes to lash down onto trailer.

Estimated hours for 3 days at Shoeburyness

0.7

Total hrs 10.5

Fuel Used 105ltr

Engine Economy

10ltr/hr

Table 5-8 Log of hours and maintenance

Comments & Observations :

• Loading/Unloading - Armtrac 100 comes ready to deploy on the back of a low loader, unloading was therefore an easy operation.

• Routine maintenance of the New Holland tractor was as per the manufacturer’s instructions.


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Figure 5 -22 GSCS mechanic carrying out checks to the flail header

Figure 5-23 GSCS mechanic carrying out checks to the power take off


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5.4 Performance

5.4.1 Flail pattern

The aim of this series of tests was to ascertain whether there were any characteristics of the flail which would affect the way in which the Armtrac 100 should be operated in the demining mode.

The following tests were carried out:

• Whilst the Armtrac 100 was stationary the flail drive was engaged and the header brought down so that the chains just touched the surface.

• As above but the chains cutting to a depth of approximately 200mm. • Armtrac 100 was set to flail over a 20m run to a depth of approximately 100mm. • Armtrac 100 was set to flail over a 20m run to the operator’s recommended depth. • A line of peat mines was laid at 100mm deep and another line at 200m deep, the

Armtrac 100 was set to flail over these lines. The aim of this test was to show that the flailing depth was constant across the whole width of the cut.

The following results were obtained:

• The flail left a uniform cut when it was brought down to touch the surface but when it was brought down to a flail depth of approximately 200mm there were signs of ridges at the base of the cut (see Figure 5-24). These ridges were seen again when the freshly flailed soil was removed after the Armtrac 100 had completed the two 20m runs.

• On the second 20m run the formation of ridges resulted in the flail depth varying between 50 and 220mm. This was thought to be due to the flail rotor speed being too low and hence the chains having insufficient inertia to maintain a straight cutting line through the soil. As one chain deviates from a straight line, there is a tendency for other chains to follow it (i.e. follow the path of least resistance) leaving ridges of untouched soil.

• This effect was less apparent in the test using the peat mines. The rotor speed was kept higher resulting in reasonably uniform cuts over the whole flailing width although some of the peat mines remained in situ (refer to Figure 5-25 and Figure 5-26). 20 of the 23 mines buried 100mm deep were struck, but only 10 of the 22 mines buried 200mm deep were struck.


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Figure 5-24 Ridges found at the base of the cut

Figure 5-25 Line of peat mines at 200mm depth before flailing


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Figure 5-26 Line of peat mines at 200mm depth uncovered after flailing


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5.4.2 Test run

The aim of this test was to gain an understanding of how Armtrac 100 operated in the clearance mode before using the more expensive MRM mines.

The layout of the runs is illustrated in Figure 5-27. Evidence of 7 of the peat mines was found and both the AT mine cases were destroyed. The final peat mine was outside of the flail width and was therefore not hit.

Figure 5-27 Layout of test runs

Key

- Peat mine, buried 75mm

- Peat mine, surface laid

- TMA-5 AT mine, flush buried


- Peat mine, flush buried

- Peat mine, buried 75mm


- TMA-3 AT mine, flush buried


- Peat mine, flush buried


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5.4.3 Obstacle Clearance

The aim of this test was to assess the clearance ability of Armtrac 100 on road structures containing roadblocks and other obstacles. Three banks constructed of rocks and logs were laid on a tarmac and gravel road. The rocks had an average diameter of 100 – 150mm and the logs ranged from 5mm to 500mm in diameter with the majority of the order of 150mm diameter. MRM’s and AT mines were placed in and around the banks.


Mine type Starting position End position/state PMN (MRM) 1 6.08m behind starting point & triggered PMN (MRM) 2 Triggered PMA-2 (MRM) 3 Destroyed PMN (MRM) 4 1.5m behind starting point & triggered TMA-2 (Wax filled case) 5, Surface Laid Destroyed TMA-3 (Wax filled case) 6, Flush Buried Left in situ but 2 fuses removed PMN (MRM) 7 Triggered & destroyed PMA-2 (MRM) 8 Destroyed

Table 5-9 Mine data for obstacle clearance course

Figure 5-28 Obstacle clearance course


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Figure 5-29 Rock obstacle before

Figure 5-30 Rock obstacle after


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Figure 5-31 Armtrac100 flailing log obstacle


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5.4.4 Brush & Vegetation Clearance

The aim of this test was to demonstrate the ability of Armtrac 100 to perform brush & vegetation clearance as part of a ground preparation role in demining, and to assess the resulting condition of the soil and vegetation. Firstly Armtrac 100 was set to clear a line of bracken, then Armtrac 100 was set to clear a line of five small shrubs of varying size. The machine was then set to clear a series of larger trees. Finally the machine was set to clear a gorse bush and a small tree on a small bank by flailing up and down the slope.

Refer to Table 5-10 for details of the vegetation cleared and to the following figures for an indication of the resulting soil condition.

Test Dimensions (approximate stem

diameter and height) Comments

Bracken Ø5mm, 1m high Cleared adequately 5 small bushes Ø20mm, 2.7m high All cleared adequately Ø46mm, 4m high Ø70mm, 4.5m high Ø80mm, 5m high Ø80mm, 6m high Silver Birch 1 Ø90mm, 10m high Cleared adequately Silver Birch 2 Ø140mm, 10m high Cleared adequately Small Tree & Gorse on a bank

Small Tree: Ø80mm, 4.5m high, gorse bush: 1m high

See below

Table 5-10 Details of vegetation cleared

The gradient of the bank was 23º; its height was 0.8m. On the first attempt the flail header grounded on the bank due to the change of gradient. The machine was backed out and the flail header was manually adjusted to get maximum height. On the second attempt it cleared the area without the flail head grounding.

The Armtrac 100 then flailed down the same slope, again the flail head dug in to the ground on reaching the positive change in gradient.


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Figure 5-32 Bracken before flailing

Figure 5-33 Bracken after flailing


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Figure 5-34 Line of shrubs before flailing

Figure 5-35 Line of shrubs after flailing


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Figure 5-36 140mm Silver Birch tree

Figure 5-37 Silver Birch after flailing


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Figure 5-38 Armtrac clearing bank


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5.4.5 Inert Minefield Encounter

Six test lanes were used covering 3 different types of terrain:

• Sandy, loamy soil with light vegetation • Compacted gravel track • Wet cohesive clay soil with light vegetation

Several soil cone penetrometer measurements were made, the following are average readings:

Sandy, loamy soil – 26,132,218

Wet clay soil – 16,37,89,118,170

No measurements were made in the gravel track due to its hardness and large number of stones present.

Four different types of mine simulant were used:

• MRM’s – Mechanical Reproduction Mines are made by Amtec and are the same size, shape and weight as the mine they seek to represent. The trigger mechanism is also very similar to the real mine but has no explosive content and when triggered breaks an identifying antenna coil. PMN and PMA-2 MRM’s were used in this trial.

• Peat mines – These are solid cylindrical shaped targets (Ø60mm x 40mm) made from compressed peat. Although they do not represent a specific mine in shape, size and have no trigger mechanism, they can be used as a ‘witness’ in a trial such as this. These simulants disintegrate under direct impact so conclusions can only be drawn if the simulants are found whole and intact either where they were placed or in the spoil left after flailing. Mines that could not be located were assumed to have been destroyed.

• Wax or concrete plastic cases – These are designed to represent a specific mine in shape, size and weight. Although they have no trigger mechanism, they can also be used as a ‘witness’ in a trial such as this. TMA-2, TMA-3, TMA-5 and TMRP-6 cases were used.

• Solid metal mine simulant - These are designed to represent a specific mine in shape, size and weight. Although they have no trigger mechanism, they can also be used as a ‘witness’ in a trial such as this. These were found to be of limited use in this trial and only two ‘Minotaur’ scatterable mines simulant were used.

The results with the lines of peat mines in section 5.4.1 indicated no appreciable difference in cutting ability across the width of the flail (although the presence of ridges indicated localised non-uniformity). Therefore it was decided to only lay the MRM’s down the centreline of the mine lanes to ensure they were within the flailing width, with peat mines and AT inert mine simulants laid in a row on either side (see Figure 5-39). In each case, the rows and columns were separated by 1m.


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Figure 5-39 Inert minefield layouts

Key - PMN MRM

- PMA-2 MRM

- Peat mine

- TMA-2 Simulant

Lane 3, Frame 2

Lane 3, Frame 1

Lane 2, Frame 2

Lane 2, Frame 1

Lane 1, Frame 2

Lane 1, Frame 1

- TMA-3 Simulant

- TMRP-6 Simulant

- Scatterable mine Simulant

- TMA-5 Simulant


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Field/Lane Terrain Summary of results Field 1, Lane 1 Sandy, loamy soil with

light vegetation 1 PMN not triggered (buried at 200mm) 1 PMA-2 not found (assumed destroyed) 2 Peat mines intact and in-situ (buried at 200mm)

Field 1, Lane 2 Sandy, loamy soil with light vegetation

1 PMN thrown 25m forward but triggered 1 PMN untriggered but fuse mechanism jammed preventing action of trigger (buried at 200mm) 1 Peat mine intact and in-situ (buried at 200mm) All others triggered or destroyed

Field 2, Lane 1 Compacted gravel track

1 PMN untriggered but with plunger punched out (assumed neutralised but not detonated) All others triggered or destroyed

Field 2, Lane 2 Compacted gravel track

1 PMN not triggered but fuse destroyed (assumed triggered) 2 Peat mines intact and in-situ (buried at 200mm) 1 PMN untriggered, in-situ (buried at 200mm)

Field 3, Lane 1 Wet cohesive clay soil with light vegetation

2 PMA-2’s intact & in-situ (buried at 200mm) 1 TMRP-6 AT mine intact & in-situ (buried at 150mm) 1 TMA-5 AT mine intact & in-situ (buried at 200mm) 1 PMN in-situ, possibly triggered by tyre or spade (result inconclusive and ∴ void) All others triggered or destroyed

Field 3, Lane 2 Wet cohesive clay soil with light vegetation

All mines triggered or destroyed

Table 5-11 Summary of inert minefield encounter

Substantial ridges of unflailed soil were again observed, particularly in the wet clay (field 3) where in places the ridges could be seen at the soil surface. This can be seen in Figure 5-40 and may explain the relatively poor performance in field 3 lane 1.


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Figure 5-40 Ridges of unflailed soil in field 3

Table 5-12 to Table 5-17 describe in more detail the state of each target and its final location relative to the start line (i.e. distance in front or behind if negative).


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The finishing positions of mine parts:

Field 1, Lane 1 Original Position

Depth of Burial (mm)

Type State & finished position relative to start line

Comments

1st Row 0 Peat Destroyed 1st Row 0 PMA-2 Destroyed, -2.2m 1st Row 0 Peat Destroyed 2nd Row 100 Peat Destroyed 2nd Row 100 PMA-2 Destroyed, -1.6m 2nd Row 100 Peat Destroyed 3rd Row 200 Peat Destroyed 3rd Row 200 PMA-2 Destroyed, 2.2m 3rd Row 200 Peat Destroyed 4th Row 0 Peat Destroyed 4th Row 0 PMN Destroyed, 1.2m 4th Row 150 TMRP-6 Destroyed, 3.2m 5th Row 100 Peat Destroyed 5th Row 100 PMN Destroyed, 1.9m 5th Row 100 Peat Destroyed 6th Row 200 Peat Destroyed 6th Row 200 PMN Untriggered, 5m 6th Row 200 Peat Destroyed 7th Row 150 TMA-2 Destroyed, in-situ 7th Row 0 PMA-2 Destroyed, in-situ 7th Row 0 Peat Destroyed 8th Row 100 Peat Destroyed 8th Row 100 PMA-2 No evidence found 8th Row 100 Peat Destroyed 9th Row 200 Peat Untouched 9th Row 200 PMA-2 Destroyed, 8m 9th Row 200 Peat Untouched 10th Row 0 Peat Destroyed 10th Row 0 PMN Destroyed, 6.8m 10th Row 0 Peat Destroyed 11th Row 100 Peat Destroyed 11th Row 100 PMN Destroyed, 9m 11th Row 100 Peat Destroyed 12th Row 200 Peat Destroyed, in-situ 12th Row 200 PMN Destroyed, 9.3m 12th Row 200 Peat Destroyed

Table 5-12 Start & finish positions for Field 1,Lane1


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Type State & finished position relative to start line

Comments

1st Row 0 Peat Destroyed 1st Row 0 PMA-2 Destroyed, -5.5m

(fragments)

1st Row 0 Peat Destroyed 2nd Row 100 Peat Destroyed 2nd Row 100 PMA-2 Destroyed, -1m (fragments) 2nd Row 100 Peat Destroyed 3rd Row 200 Peat Destroyed 3rd Row 200 PMA-2 Destroyed, 0m (fragments) 3rd Row 200 Peat Destroyed 4th Row 0 Peat Destroyed 4th Row 0 PMN Destroyed, 0m 4th Row 0 Peat Destroyed 5th Row 150 TMA-4 Destroyed, 2m 5th Row 100 PMN Destroyed, 2m 5th Row 100 Peat Destroyed 6th Row 200 Peat Destroyed 6th Row 200 PMN Untriggered but trigger

mechanism jammed A piece of cap liner jammed in the trigger mechanism preventing initiation

6th Row 200 Peat Destroyed 7th Row 0 Peat Destroyed 7th Row 0 PMA-2 Destroyed, 3.3m 7th Row 0 Peat Destroyed 8th Row 100 Peat Destroyed 8th Row 100 PMA-2 Destroyed, 5m 8th Row 100 Peat Destroyed 9th Row 200 Peat Destroyed 9th Row 200 PMA-2 Destroyed, 8m 9th Row 200 Peat Untouched 10th Row 150 TMA-2 Destroyed, 7m 10th Row 0 PMN Destroyed, 25m forward,

16m to left

10th Row 0 Peat Destroyed 11th Row 100 Peat Destroyed 11th Row 100 PMN Destroyed, 8m 11th Row 100 Peat Destroyed 12th Row 200 Peat Destroyed 12th Row 200 PMN Destroyed, 9m 12th Row 200 Peat Destroyed



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Type Finished Position Comments

1st Row 0 Peat Destroyed 1st Row 0 PMA-2 Destroyed, -6m & -4.5m

(fragments)

1st Row 0 Peat Destroyed 2nd Row 100 Peat Destroyed 2nd Row 100 PMA-2 Destroyed, -4.3m & -3.7m

(fragments)

2nd Row 100 Peat Destroyed 3rd Row 200 Peat Destroyed 3rd Row 200 PMA-2 Destroyed, 2m (fragments) 3rd Row 200 Peat Destroyed 4th Row 0 Peat Destroyed 4th Row 0 PMN Destroyed, 0m 4th Row 0 Peat Destroyed 5th Row 150 TMA-4 Destroyed, -0.8m & 0m 5th Row 100 PMN Destroyed, 0m 5th Row 100 Peat Destroyed 6th Row 200 Peat Destroyed 6th Row 200 PMN Destroyed Untriggered but with plunger

punched out 6th Row 200 Peat Destroyed 7th Row 0 Peat Destroyed 7th Row 0 PMA-2 Destroyed, -3m & -1.6m 7th Row 0 Peat Destroyed 8th Row 100 Peat Destroyed 8th Row 100 PMA-2 Destroyed, -3m & 0m 8th Row 100 Peat Destroyed 9th Row 200 Peat Destroyed 9th Row 200 PMA-2 Destroyed, 2m 9th Row 200 Peat Destroyed 10th Row 150 TMA-2 Destroyed, 7m & 7.6m 10th Row 0 PMN Destroyed, (not found) Coil broken so not detected,

recovered by sifting with mechanical digger.

10th Row 0 Peat Destroyed 11th Row 100 Peat Destroyed 11th Row 100 PMN Destroyed, 7.6m 11th Row 100 Peat Destroyed 12th Row 200 Peat Destroyed 12th Row 200 PMN Destroyed, 27m Coil live but trigger plunger

punched out of the bottom 12th Row 200 Peat Destroyed



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1st Row 0 Peat Destroyed 1st Row 0 PMA-2 Destroyed, -7.5m & -6m (fragments) coil

found at -3m

1st Row 0 Peat Destroyed 2nd Row 100 Peat Destroyed 2nd Row 100 PMA-2 Destroyed, -5.2m (fragment & fuse top) 2nd Row 100 Peat Destroyed 3rd Row 200 Peat Destroyed 3rd Row 200 PMA-2 Destroyed, -4.6m & -3.9m (fragments) 3rd Row 200 Peat Untouched, in-situ 4th Row 0 Peat Destroyed 4th Row 0 PMN Destroyed, 21.2m forward of the start line

& 3.2m to the left of the centreline

4th Row 0 Peat Destroyed 5th Row 100 Peat Destroyed, 5th Row 100 PMN Destroyed, 1.3m 5th Row 150 TMA-4 Destroyed, -3m, -2.2m, -1m, 1m & 3.5m 6th Row 200 Peat Destroyed 6th Row 200 PMN Untriggered, in-situ 6th Row 200 Peat Untouched, in-situ 7th Row 0 Peat Destroyed 7th Row 0 PMA-2 Destroyed, 0m 7th Row 0 Peat Destroyed 8th Row 100 Peat Destroyed 8th Row 100 PMA-2 Destroyed, -0.3m (fragments) 8th Row 100 Peat Destroyed 9th Row 200 Peat Destroyed 9th Row 200 PMA-2 Destroyed, 7.8m (body) & 10m 9th Row 200 Peat Destroyed 10th Row 0 TMA-5 Destroyed, 3.5m & 4.7m 10th Row 0 PMN Neutralised, 4.7m untriggered but without

striker, spring & cap

10th Row 0 Peat Destroyed 11th Row 100 Peat Destroyed 11th Row 100 PMN Destroyed, -3.9m 11th Row 100 Peat Destroyed 12th Row 200 Peat Destroyed Only slight

surface damage 12th Row 200 PMN Destroyed, in-situ but triggered 12th Row 200 Peat Destroyed



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Field 3, Lane 1 Original Position Depth of

Burial (mm) Type Finished Position Comments

1st Row 0 PMA-2 Destroyed, -0.65m 2nd Row 100 PMA-2 Destroyed, 0.4m & 2m 2nd Row 150 TMRP-6 Untouched, in-situ 3rd Row 200 PMA-2 Untriggered, in-situ 4th Row 0 PMN Destroyed, 2m 5th Row 100 PMN Destroyed, 4m & 5m 6th Row Surface Minotaur Hit, 6m 6th Row 200 PMN Destroyed, 6m Triggered but intact 6th Row 150 TMA-5 Untouched, in-situ 7th Row 0 PMA-2 Destroyed, 8m 8th Row 100 PMA-2 Destroyed, 8m 9th Row 200 PMA-2 Untriggered, in-situ 10th Row 0 PMN Destroyed, 10m 11th Row 100 PMN Destroyed, 11m 12th Row 200 PMN Void (intact) Possibly triggered by

digging with spade





1st Row 0 PMA-2 Destroyed, -1.5m & 0.8m (fragments) 2nd Row 100 PMA-2 Destroyed, 4.3m 3rd Row 200 PMA-2 Destroyed, 4.3m 4th Row 0 PMN Destroyed, 4.3m 4th Row 150 TMRP-6 Destroyed, in-situ 5th Row 100 PMN Destroyed, 4.3m 6th Row 200 PMN Destroyed, 6.2m 6th Row Surface Minotaur Hit, 4.3m 7th Row 150 TMA-2 Destroyed, in-situ 7th Row 0 PMA-2 Destroyed, 4.6m (fragments) 8th Row 100 PMA-2 Destroyed, 7.1m & 6.2m (fragments) 9th Row 200 PMA-2 Destroyed, 9.5m & 11.9m 10th Row 0 PMN Destroyed, 9.5m 11th Row 100 PMN Destroyed, 9.5m 12th Row 200 PMN Destroyed, 11.9m



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5.5 Survivability against mine attack

The Armtrac 100 was subjected to a range of explosive blasts using plastic explosive (PE) in various configurations, to represent anti-personnel (AP) blast mines, fragmentation mines and anti-tank (AT) blast mines. All charges were electrically command detonated.

5.5.1 AP Blast mine – 1st firing

240g of PE was placed on the ground surface directly beneath the static flail rotor and command detonated.

Figure 5-41 Plan view of flail header for 1st firing

The detonation of the 240g charge resulted in no visible damage

FLAIL RO

TOR

240g PE


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Figure 5-42 Location of charge 1


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5.5.2 AP Blast mine – 2nd firing

100g of PE was attached to the inside face of the cowling blast plate, immediately behind the flail rotor, in order to simulate an AP mine which had been scooped up by the flail and detonated as it hit the cowling.

Figure 5-43 Front view of flail header for 2nd firing

The 100g charge resulted in a hole approximately 50 x 80mm in the armour plate. Superficial damage was evident to the structural components behind the plate, but there was no apparent effect on the structural integrity or operation of the flail unit.

100g PE


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Figure 5-44 Front view of the flail header with charge in place

Figure 5-45 Front view of the flail header with charge detonating


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Figure 5-46 Hole in the flail blast plate


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5.5.3 AP Blast mine – 3rd firing

150g of PE was placed on the ground immediately beneath one of the rubber flaps at the base of the flail cowling.

Figure 5-47 Plan view of flail header for 3rd firing

The charge resulted in slight damage to two of the rubber flaps, which were partially torn from their mounting brackets, but remained attached. There was no apparent effect on the structural integrity or operation of the flail unit.

FLAIL RO

TOR

150g PE


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Figure 5-49 Damage to rubber flaps


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5.5.4 AP Blast mine – 4th firing

The flail was lowered as far as possible and 150g of PE was placed on the ground surface, immediately beneath the blade on the underside of the left hand flail support arm i.e. the part closest to the ground.

Figure 5-50 Plan view of flail header for 4th firing

The charge resulted in no visible damage.

FLAIL RO

TOR

150g PE


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Figure 5-52 Front view of the flail header with charge detonating


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5.5.5 AP Blast mine – 5th firing

A shallow trench was created in the ground with the flail, which was then stopped and left in position. 240g of PE was buried just in front of the trench at a depth of about 50mm.

Figure 5-53 Plan view of flail header for 5th firing

The charge resulted in a noticeably larger blast than the first firing and caused several of the cowling vent flaps to open. However there was no visible damage to the flail unit.

FLAIL RO

TOR

240g PE 50mm deep

700mm


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5.5.6 AP Fragmentation mines

Two POMZ-2M fragmentation mine case were filled with 100g of PE and mounted on stakes in front of and to the side of the flail unit, with the top of the mines 260mm above the ground surface. The windows of the Armtrac 100 were covered with rubber sheets to protect them. It was considered unnecessary to subject the windows to attack, as they were constructed of a standard armoured glass of a known specification (45mm polycarbonate/glass laminate).

Figure 5-55 Plan view of the flail header for fragmentation mines

The mines were command detonated in turn. Mine 1 resulted in no visible damage to the flail unit, other than a few small surface scratches on the cowling. Mine 2 resulted in indications of very small fragment impacts on the flail arm, engine cowling, windows and fuel tank. There was no apparent effect on the structural integrity or operation of the flail unit.

FLAIL RO

TOR2m

2m

0.7m

2

1


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Figure 5-56 Front view of the flail header with fragmentation mine

Figure 5-57 Front view of the flail header with fragmentation mine detonating


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Figure 5-58 Side view of the flail header with second fragmentation mine

Figure 5-59 Side of flail support arm after second fragmentation mine firing


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5.5.7 AT Blast mine – 1st firing

5.5 Kg of PE was placed inside a replica TMRP-6 AT mine plastic case, to represent a typical AT blast mine. The flail unit was used to create a shallow trench in the ground and was then raised slightly and powered down. The mine was buried 1.2m in front of the centre of the flail rotor, about 100mm below the surface (to the top of the main body of the mine). Ideally the mine would have been placed directly beneath the rotor or just in front of it, i.e. in a position so as to be hit by one of the chains. However this would have made arming and firing the charge impossible with a rotating flail, hence an extra ‘stand-off’ distance was required. The flail unit was then powered up again and the mine command detonated. A remote cut-off switch had been connected to the Armtrac 100 so that the unit could be shut down from a safe distance following the blast.

Figure 5-60 Plan view of flail header for first AT firing

FLAIL RO

TOR

5.5 Kg PE 100mm deep

1200mm


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Figure 5-61 Location of first AT charge

The blast lifted the front wheels of the Armtrac 100 and moved the whole vehicle backward about 50mm. The upper flail unit hydraulic pistons were seen to compress and extend again, both ending up 50mm shorter than originally set. Eight of the cowling doors were blown off and ended up in the positions shown in Figure 5-62 below. The blast left a crater in the ground 2.8m wide, 2.5m long and 1.0m deep.

The right hand drivers mirror glass was cracked. The flail unit mounting was slightly distorted (see Figure 5-64 below) – the gap between the mounting plate and front of the engine housing had been about 10mm before the blast and increased to about 30mm. A bolt head on the right hand flail support arm had been sheared off, probably by one of the chains, resulting in a small amount of grease seeping from the cover (see Figure 5-65). However the flail unit continued running normally after the blast and the entire vehicle appeared to be fully operational.

The undamaged cowling doors were then repositioned into the lower positions, so as to provide maximum protection for the second blast – no replacement doors were available. This repair (requiring simple hand tools only) took two men about 20 minutes, including a general vehicle inspection.


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Figure 5-62 Distribution of cowling doors after 5.5Kg AT blast

Figure 5-63 Flail cowling after first AT blast

20m

80m

60m

40m


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Figure 5-64 Distorted flail unit mounting

Figure 5-65 Flail drive chain cover - showed sheared bolt head


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5.5.8 AT Blast mine – 2nd firing

A second charge was set up in a similar way to the first, but 7 Kg of PE was used and it was placed in line with one end of the rotor, 0.85m in front of it and 110mm deep. The flail unit was raised slightly higher than in the previous test, and was again running when the charge was detonated.

Figure 5-66 Plan view of flail header for second AT firing

Figure 5-67 Location of second AT charge

FLAIL RO

TOR

7 Kg PE 110mm deep

850mm


Page 69 of 88

The front of the vehicle was lifted off the ground and moved 260mm to the left, whilst the whole vehicle was moved 70mm backwards. The top left hydraulic ram was 5mm shorter than originally set, the top right 3mm shorter, whilst the bottom left ram was 2mm longer and the bottom right 7mm shorter (indicating a twisting motion of the flail unit).

Six cowling doors were blown off (only 13 of the original 21 were fitted), ending up in the positions shown in Figure 5-68 below, and 3 of the remaining doors were left in place but with their rubber spring hinges sheared off. The blast left a crater in the ground 3.3m wide, 3.5m long and 1.1m deep.

Close inspection of the vehicle revealed that the gearbox guard plate (under the front of the tractor unit) had been pushed back and was touching the steering link arm on the right hand side (see Figure 5-71). This was thought to have occurred after the first AT blast, however it did not appear to impede operation of the steering. The right hand chassis rail had also distorted slightly at a point where two holes were drilled through it, highlighting a weakness in its design (see Figure 5-72). The flail unit mounting had distorted slightly further, but it was noted that this could easily have been prevented or reduced by more substantial attachment of the top of the mounting plate to the tractor. A weld in one of the flail cowling support arms had cracked (see Figure 5-73) and a small oil leak was detected in the front differential – however this may have been present before the blast. The flail unit continued running normally after the blast and the entire vehicle was fully operational.

Figure 5-68 Distribution of cowling doors after 7Kg AT blast

20m

80m

60m

40m

100m


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Figure 5-69 Final position of one of the cowling doors

Figure 5-70 Flail cowling after second AT blast


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Figure 5-71 Gearbox guard plate touching steering link arm

Figure 5-72 Distorted chassis rail


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Figure 5-73 Cracked weld in flail cowling support arm


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6 Conclusions

6.1 Transportability

As was witnessed during the trial, the Armtrac 100 can be transported on a low-loader.

The Armtrac 100 can be transported whole or the flail unit can be detached and transported separately (although detachment of the flail wasn’t demonstrated during the trial).

The limiting factors for transportation of the Armtrac 100 as a complete unit are as follows:

• The transporter must have a load capacity greater than 11010kg (Gross vehicle mass of Armtrac 100).

• Consideration should be given to the load distribution since ~65% of the Armtrac 100’s mass is on the front axle.

• Loading ramps must have an angle shallower than 22.5°.

• The length of the load is 6.85m and its width is 2.64m.

• The height of the load is 2.9m.

6.2 Mobility

Armtrac 100 is based on an agricultural tractor potentially giving it a good mobility. The all wheel drive transmission provides good traction, although the added weight of the flail unit and armour tends to make the wheels sink on soft terrain, particularly the front wheels.

The flail header significantly restricts forward visibility, particularly when driving with the flail raised.

During the tilt test it lost balance on approximately a 20° side-slope and approximately 51° with the machine facing down the slope. However, it is likely that Armtrac 100 will lose traction well before losing balance when ascending or descending a slope, particularly on slippery off-road surfaces.

The Armtrac 100 can turn within a 17.5m diameter circle that can be further reduced by braking one of the rear wheels. This helps to counter the restriction on manoeuvrability due to the large size of the flail unit.

The Armtrac 100 is fully road legal and with a cruising speed on road of 35kph (51kph top speed recorded) it will be able to travel easily from a central depot to a remote minefield easing the burden on logistics. In the flailing mode, Armtrac 100 achieves a reasonable clearance rate on a single pass at an average speed of 0.39kph.


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6.3 Performance

The flail left a uniform cut when it was brought down to touch the surface but when it was brought down to a flail depth of approximately 200mm there were signs of ridges at the base of the cut. In heavier soil, ridges were observed that were anything from a few mm high all the way up to the ground surface. It was thought that these ridges were due to the flail heads following ‘the path of least resistance’ due to a loss of momentum when striking the ground.

Due to the above characteristic it was found that in normal clearance mode the flail had a good clearance performance down to 100mm over all three terrain types used. The clearance performance reduced when the mines buried at depths of 150mm and 200mm to the top of the target were considered. Table 6-1 below summarises the clearance performance against the MRM targets. Figures have not been provided for the peat mines, due to the uncertainty over whether they had been destroyed when they could not be located.

Soil Type 0mm DOB 100mm DOB 200mm DOB

Sandy 8/8 8/8 7/8

Gravel 8/8 8/8 7/8

Wet clay 8/8 8/8 5/7

Table 6-1 Summary of MRM clearance performance

The small number of mines cleared means that no great statistical confidence can be derived from these results, rather they are indicative of the capability of the machine.

Some of the targets mentioned above could have been missed through failure of the machine to maintain a constant flailing depth over varying terrain since depth control is performed manually by the driver. It was apparent that this required considerable skill and familiarity with the machine, particularly on rough terrain.

Some of the MRMs were neutralised but not detonated (e.g. the fuse was broken off but not triggered). There is therefore a real possibility of live explosive components being thrown by the machine into previously cleared areas (mine parts were occasionally thrown up to 30m). This factor must be taken into account when considering the role of this machine in a clearance operation.

The Armtrac 100 performed well on the obstacle clearance test destroying all three ‘road blocks’ and all the mine targets in and around them.

The Armtrac 100 performed well as a brush & vegetation clearance device, reducing medium density bushes and trees up to a diameter of 140mm and 10m in height to ground level. A characteristic of the Armtrac 100 (as is with most flails) is a tendency to throw the spoil over a large area. However, in the case of the Armtrac 100 this is reduced due to the cover over the flail.

During the brush & vegetation clearance tests the main limiting factor of the Armtrac 100 was the approach angle causing the flail header to ground out when climbing and descending banks. This could be countered to an extent by flailing banks in order to reduce their height, but it was clear that maintaining a constant flailing depth over terrain


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with significant changes in gradient would be very difficult for even the most skilled operator.

The vehicle was reliable during the period of the trial, requiring only routine maintenance. However the limited operating time was not considered sufficient to allow any conclusions to be drawn regarding reliability under realistic operating conditions or overall running costs.

6.4 Survivability

The Armtrac 100 proved itself to be capable of surviving attack from a range of AP blast and fragmentation mines and AT blast mines in and around the flail unit. None of the AP-sized blasts appeared to inflict any significant damage other than the charge that was taped directly onto the blast plate. This represented an unusual but not impossible scenario and served to highlight the need to ensure adequate protection for the flail drive mechanism behind.

The two fragmentation mine blasts inflicted significantly less damage than was anticipated. It is believed that the use of 100g of PE rather than 75g of TNT in the mines represented a greater threat than real PMN-2Ms, so it seems likely that the minimal damage was due to the high level of protection of the vehicle. However, a more thorough assessment of the vulnerability of the vehicle to this type of threat would have required many more blasts from a much wider range of angles, with a much higher likelihood of permanent damage to the vehicle. This would have highlighted the effect that fragmentation mines may have on certain obviously vulnerable parts of the vehicle such as the vents in the engine compartment and hydraulic hoses, but was not possible within the scope of this trial.

The two AT-sized blasts provided much useful information. The most significant conclusion is that the flail unit is well designed for the venting of large explosive blasts, as was demonstrated by its ability to continue normal operation following both blasts. The large forces exerted on the structure highlighted certain weak points, but these were all relatively minor and could all have been improved with straightforward strengthening or reinforcing. In both cases the explosive was located slightly forward of the reach of the flail chains, so a real detonation would only take place with the charge closer to the vehicle, with a consequently increased risk of damage. The large area over which the cowling vent doors were thrown indicated the need for a very large safety distance when operating this machine. It should be noted that eight of the doors were not in place for the second (larger) blast, so a safety distance of at least 200m in all directions is recommended.

One test that was not possible to conduct was an AT blast under one of the wheels, due to the likely damage that this would have inflicted on the vehicle. Although the machine is intended to detonate or destroy AT mines by flailing them, it is quite possible that a deeply buried mine could be missed by the flail but subsequently triggered by the vehicle driving over it. Such an incident would present a significantly greater risk to both vehicle and operator than triggering a mine under the flail.

No tests were conducted to directly assess the protection of the operator. As stated above, much more extensive testing with large blasts under the wheels and cab as well as fragmentation and off-route mines, shaped charges and unexploded ordnance would need to be conducted to draw any detailed conclusions regarding operator safety, along with suitable instrumentation to measure such things as shock and acceleration levels.


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This type of testing was beyond the scope of this trial and would have caused an unacceptable level of damage to the vehicle.


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7 Recommendations

7.1 Armtrac 100

The mobility of the Armtrac 100 was occasionally restricted by the flail unit hitting the ground, particularly when encountering a sudden change of gradient e.g. loading ramps. This effect would be reduced if the header could be raised higher or were modified to increase the approach angle.

Although the flail performed adequately, it was observed that a high rotor speed had to be maintained to avoid the chains spreading and leaving untouched ridges in the soil. This required considerable operator skill in maintaining a suitable balance between engine RPM, forward speed and flailing depth. It is recommended that the engine power be increased to make it easier for the operator to maintain a suitable rotor speed and flailing depth. Redesign of the hammers on the ends of the chains in order to increase their inertia or reduce the resistance from the soil may also improve their cutting ability and so should be considered. It was noted that GSCS are using higher power engines in newer versions of the Armtrac 100 and are working on a new configuration of chains.

In the hands of an experienced operator it was seen that the Armtrac 100 kept a reasonably constant depth of cut. However, it is recommended that some form of depth of cut feedback or monitor is considered, to aid the driver when flailing over less hospitable terrain.

During the brush cutting and obstacle clearance tests the Armtrac 100 threw debris not only forward but also off to the side and rear. It is evident that GSCS have worked hard to reduce the speed and distance of debris thrown forwards and directly backwards with the design of the cowling over the flail and the rubber skirting at the base of the back-plate. It is recommended that consideration be given to extending the rubber skirting at the base of the back-plate around the sides of the flail header so as to reduce the scattered debris, although the additional skirts may confine the blast from any mines detonated increasing the likelihood of damage to the machine.

Several weak points on the structure were identified that didn’t compromise the structural integrity or operation of the vehicle following the AT blasts, but which could easily be improved. It is recommended that the mounting of the flail unit to the tractor and the gearbox guard plate be strengthened and the chassis reinforced around drilled holes, in order to reduce the likelihood of distortion at these points. The cowling support arms should be strengthened around the region of the weld that cracked following the second AT blast and consideration should be given to using countersunk instead of hex-head bolts to secure the flail chain drive covers, to reduce the likelihood of the bolt heads being damaged by the chains.

The vent doors on the cowling were thrown backwards over 120m due to the forces exerted by the AT Blast. Since the option of securing the doors to the cowling more firmly may affect their ability to vent the blast it is recommended that a safety distance of at least 200m should be observed whilst the machine in a flailing mode. (It is acknowledged that demining SOP’s probably require a greater safety distance than this).


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Since the survivability tests were carried out without any instrumentation of the driver’s environment further tests on this aspect are recommended.

7.2 Trial Methodology

This trial was conducted with international co-operation, which, on the whole, had a beneficial effect, by bringing together ideas and methodology not used together before. It is therefore recommended that representatives of a range of international organisations be invited to participate in future trials.

Although not perfect it was found to be very useful to group tests under four main categories:

• Transportability • Mobility • Performance • Survivability

Under these headings there was a certain amount of crossover between tests in one category and those in another. Further work is recommended to define categories of tests such as above. Once this is done it will allow for a greater homogeny of testing allowing different groups of test engineers to more accurately identify which areas of testing have been carried out and which areas require further testing.

This is the first QinetiQ trial where Mechanical Reproduction Mines have been used and, although relatively expensive, were found to greatly improve the testing procedure for inert minefield testing. It is recommended that future testing of this type of equipment make use of these mines and build on the test procedures used for this trial. The peat mines, though very cheap, proved difficult and time consuming (hence expensive) to locate and identify after a flailing run. The MRMs could be located and identified far quicker which served to at least partially offset their significantly higher unit cost. The peat mines did however prove useful in assessing the flailing characteristics of the machine, when buried in lines at various depths, and so should also be used for future testing.

Although data was taken with regards to soil strength and ground pressure there has not been time so far to define these factors fully. If ground pressure is considered to be an important aspect of this type of machine, an appropriate test methodology should be devised to assess it.

It was not possible to conduct any climatic or durability testing of the vehicle. These are very important aspects where vehicles will be expected to work reliably in remote areas in hot, dusty environments. If considered necessary test procedures should be defined to assess the ability of vehicles to operate for extended periods under extreme conditions.


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8 Acknowledgements

QinetiQ would like to like to thank representatives of the following organisations for their help during the trial:

• Chris Leach – QinetiQ, UK • Pete Blatchford – QinetiQ, UK • Geoff Coley – CCMAT, Canada • François Littmann – JRC, EC • Göran Danielsson – SWEDEC, Sweden • Ola Modigs - FMV, Sweden • Anders Gustafsson – FMV, Sweden


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9 References

1. Armtrac 100 Evaluation Trials Plan, P. W. Blatchford,

QINETIQ/FST/CRMV/TI021261, February 2002. 2. Armtrac 100 Evaluation Safety Plan, P. W. Blatchford,

QINETIQ/FST/CRMV/SAF021266, December 2001.


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10 Appendix - Pre-Trial Report for Armtrac 100

14th February 2002


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Introduction

Background

Ground Sift and Clear Systems (GSCS) manufacture three types of machine: Armtrac 75, Armtrac 100 and Armtrac 325. GSCS’s factory unit, situated on a farm, is small but well equipped for low volume fabrication work. G3 Systems, a defence contractor, has bought and marketed several Armtrac 100’s.

QinetiQ has been tasked by DFID to carry out pre-trial assessment and a full trial of the Armtrac 100 pending the results of the initial pre-trial assessment.

Armtrac 100

The Armtrac 100 is based on a New Holland agricultural tractor with a flail unit attached to the front PTO (Power Take Off). GSCS remove the cab and the non-structural body parts from the tractors and replace them with armour plate. The driver’s cab is rebuilt with armour plate, toughened glass and additional strengthening to the seat and driver’s harness.

As mentioned above, the flail unit is run from the front PTO, the manufacturer mentioned that the flail unit could be very easily interchanged with either a Milling Drum or Runway Clearance Device. Unfortunately, we were unable to see either the Milling Drum or Runway Clearance Device.

Since the Armtrac 100 is based on an agricultural device it can be used for non-demining activities as well.

GSCS currently has machines deployed in Bosnia & Mozambique.

Assessment Criteria

Using the assessment criteria specified in the DFID draft paper on Mine Action Policy for the T&E of Mine Action Equipment (Annex A).

Capability Gap

Although Armtrac 100 is a flail, and therefore nothing new, it scores well in this category because of the following:

The tractor unit is based on a New Holland agricultural tractor: New Holland has a world-wide spare part and servicing network.

When finished demining operations it can be easily converted for other uses such as agriculture and forestry.

The flail unit is only one of the tools that can be fitted to this machine. It can also be fitted with a Milling Drum or Runway Clearance Device.

Efficiency & Safety

Without seeing the machine in action it is hard to determine efficiency & safety of the machine. However, from a safety aspect it was evident that the manufacturer has given a lot of thought to driver safety and had sought advice on the correct armouring of the


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cab. All that can be said about the efficiency of the Armtrac 100 is that is not excessively large for a demining machine and that it uses a modern turbo-charged diesel engine.

Standards

There is nothing new about the technology behind a flail, on inspection of the flail head of Armtrac 100 it was seen that the chains were sufficiently close together along the axle that there is little chance that AP mines would pass through without being hit. It is the opinion of the author that this machine has the potential be an efficient tool to assist in the clearance of known mined areas.

Human Factors

As mentioned above the Armtrac 100 is based on a common modern agricultural tractor unit, this makes the unit very user friendly. There is only one concern, that the operation of the flail head requires a constant input from the driver who has no direct way of judging the flail depth and has to rely on monitoring of the flail speed and to ‘get a feel for it’. Due to the lack of all-round visibility the Armtrac 100 may have to be guided by an extra man whilst manoeuvring in tight areas but in the mine clearance mode only the driver is required.

Environment

Flails do damage the soil structure; to offset the affects of this GSCS has also designed a milling drum that can be used in place of the flail on areas where it is advantageous to preserve the soil structure.

Development Status

The Armtrac 100 has reached a production stage and several are already working in mine affected countries.

Local Manufacture & Repair

The Armtrac 100 has a relatively simple design. The tractor unit is based on a New Holland design who have a world-wide spare parts and servicing network, the flail unit is mechanically driven and repairs and maintenance should be possible with basic workshop tools.

Intellectual Property Rights

The GSCS is happy to have the results of the trial placed in the public domain without restriction. QinetiQ will endeavour to involve the GSCS at all points of the trial and will be happy to listen to any comments they may have on the report before publishing.


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Criteria Score (/5) Weighting Worth Score Capability Gap 4 1.5 6 Efficiency & Safety 3 2 6 Standards 3 1 3 Human Factors 5 1.25 6.25 Environment 3 1.25 3.75 Development Status 4 1.5 6 Local Manufacture & Repair 4 0.75 3 Intellectual Property Rights 4 1.5 6 Total: 40

Worth Score Table for Armtrac 100

Conclusion

The Armtrac 100 fulfils the above criteria. It is, therefore, recommended that this machine is ready to proceed in a full trial of its Transportablity, Mobility, Performance and Survivability.


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Distribution list

Mr A. Wilson - DFID Mr S. Brown - GSCS Mr B. Stratton - G3 Systems Mr A. Craib - Baric Consultants Mr D. Lewis - QinetiQ Mr C. Leach - QinetiQ Mr P. Blatchford - QinetiQ Mr G. Coley - CCMAT Mr G. Danielsson - SWEDEC Mr F. Littman - JRC Mr O. Modigs - FMV Mr A. Gustafsson - FMV File – Countermine library HD1/7/1


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Unclassified


Unclassified

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Report documentation page

1. Originator's report number: QINETIQ/FST/CRMV/CR022665

2. Originator's Name and Location: Mr C A Leach Bldg 412, QinetiQ Pyestock, FRN

3. MOD Contract number and period covered: 183660 0002

4. MOD Sponsor's Name and Location:

5. Report Classification and Caveats in use: 6. Date written: Pagination: References:

April 2002 xii + 88 2

7a. Report Title: Armtrac 100 Trial Report

7b. Translation / Conference details (if translation give foreign title / if part of conference then give conference particulars):

7c. Title classification: UC

8. Authors: C.A.LEACH

9. Descriptors / Key words: HUMANITARIAN, DEMINING, FLAIL, TRIALS, LANDMINES

10a. Abstract. (An abstract should aim to give an informative and concise summary of the report in up to 300 words).

This report is a technical assessment of the Armtrac 100 Mine Flail. The equipment consists of a flail unit with cowling attached to an armoured agricultural tractor.

The trial was carried out after QinetiQ staff underook a pre-trial assessment of the vehicle for the Department For International Development (DFID).

The report concludes that the Armtrac 100 Mine Flail is a well designed and capable machine. It demonstrated an ability to clear anti-personnel sized mines from terrain ranging from sandy topsoil to gravel track and heavy clay, but with limitations on clearance depth. It also concludes that the Armtrac 100 has good vegetation clearance ability and good mobility. The machine survived a limited range of live explosive tests, although these did not fully assess the safety of the operator.

Overall, the objectives of the trial were achieved by demonstrating the concept of using a flail to clear mines and dense foliage from various terrains. As with most mechanical clearance processes the application of this equipment has to be in the context of the mine threat, type of terrain, climatic and environmental conditions and of the overall demining operation.

10b. Abstract classification: UC FORM MEETS DRIC 1000 ISSUE 5

Unclassified


Unclassified

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Documents

Armtrac Report final - gichd.org