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    Department of Aeronautical Engineering

    University of Bristol

    UB2008FColossus

    Sub-Section 7:

    Stability & Control

    Authors:

    Mike DennisonMartin Bracewell

    Becky Hutchinson

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    Three-View

    General DetailsModel Description High payload, long

    range freighter

    aircraftList Price Std/HO (2007

    $USm)

    287.95

    Launch 2015

    Entry into Service 2020

    Accommodtn (space ltd) 6 x PAG, 38 x LD3,33 x PMC118

    Accommodtn (payld ltd) 18 x PAG, 4 x LD3,

    33 x PMC118

    Design CriteriaMax Operating Vmo/Mmo 510 KTAS / 0.89M

    Dive VD/MD 528 KTAS / 0.92M

    Certified Max Alt. 12530m / 41100ft

    Landing Gear VLO/VLE

    Max. Flaps VFE 205 KCAS

    External Geometr Wing (Canard)Overall Length 79.62m/261.2ft

    Overall Height 22.47m/73.72ft

    Wingspan 75.0m/246.1ft

    (25.5m/83.7ft)

    Wing Area (gross) 680m2 / 7319ft2

    Wing Area (ESDU) 596m2 / 6410ft2

    Canard Area (gross) 111m2 / 1195ft2

    Canard Area (ESDU) 71.1m2 / 765.3ft2

    Wing/Canard ARatio 9.92 / 5.87

    1/4 Chd Swp 33.0 deg (35.0 deg)

    t/c - Root / Kink 1 /

    Kink 2 / Tip

    0.14/ / /0.105

    Cabin Geometry

    Max no ULDs 14 x PGA or

    33 x AMA or

    33 x PMC or

    33 x AAK

    Cabin length

    Top:

    Upper Cargo:

    Lower Cargo:

    9.46m / 31.04ft

    49.97m / 157.38ft

    47.53m / 155.94ft

    Cabin volumeTop:

    Upper Cargo:

    Lower Cargo:

    78.30m / 2765ft3 3

    1026.2m / 36239.9ft3 3

    375.4m3 / 13257.1ft3

    Max cabin width

    Top:

    Upper Cargo:

    Lower Cargo:

    5.77m / 18.9ft

    6.82m / 22.4ft

    6.8m / 22.3ft

    Cabin floor width

    Top:

    Upper Cargo:

    Lower Cargo:

    5.77m / 18.9ft

    6.82m / 22.4ft

    5.18m / 17.0ft

    External

    Fuselage width:

    Fuselage height:

    7.11m / 23.33ft

    8.51m / 27.92ft

    Total cargo volume 909.3m3 / 32112ft3

    Payload net density 58.6kg/m2 / 12 lb/ft2

    Colossus

    Fuselage Cross-SectionDeck Layouts

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    Cargo Doors/Access

    Cargo door

    size

    (Wdth x hght)

    upper cargo: 3.4 x 3.18m

    11.2 x 10.43 ft

    lower fwd: 2.64 x 1.68m

    8.66 x 5.51ft

    lower aft: 2.64 x 1.68m

    8.66 x 5.51ft

    SystemsEngine Rolls Royce Trent 900

    Or GP7000 Derivative

    APU NASA/Boeing Concept 440kW

    Solid oxide fuel cell

    Avionics Proprietary

    Payload-Range Diagram

    Payload Range

    0

    20

    40

    60

    80

    100

    120

    140

    160

    180

    200

    0 2000 4000 6000 8000 10000 12000

    Range (nm)

    Payload(

    x1000kg)

    Weights & LoadingsMaximum Ramp Weight 557480kg / 1229012lb

    Maximum Takeoff Weight 557010kg / 1227976lb

    Maximum Landing Weight 473460kg / 1043783lb

    Max Zero-Fuel Weight 373960kg / 824427lb

    Operationl Weight Empty 198960kg / 438624lb

    Maximum Payload 175000kg / 385802lb

    Maximum Usable Fuel: 310336L / 81991USG

    ** 6.75 lb per USG 251040kg / 553439lb

    Payload at max. fuel 107480kg / 236949lb

    Wing Loading (MTOW) 711.1kg/m2

    145.7lb/ft2

    Thrust(max SLS)to Weight

    (MTOW)

    2.49 N/kg

    0.254 lbf/lb

    Empty Weight/mx payload 1.14

    OWE/MTOW Fraction 0.36(MZFW-OWE)/MTOW Fractn 0.31

    Max Fuel Fraction 0.45

    Performance

    Engine Rating 356kN / 80000lbf

    Takeoff Rating max 354kN / 79512lbf

    Flat Rating ISA+15 at T/O

    Airfield Performance (MTOW/MLW)

    BFL, ISA+15C, SL 2745m / 9006ft

    LFL, ISA, SL 2060m / 6759ftApproach Speed (MLW) 155kts / 0.24M

    En route Perf: Climb (AEO, ISA, MTOW br.)

    Time to Climb to FL 350 27 min

    Time to Climb to ICA 27 min

    Initial Cruise Altitude 10670m / 35000ft

    En route Performance: Cruise

    Long Range Cruise 487kts / 0.85M

    High Speed Cruise 510kts / 0.89M

    Payload-Range

    Reserves Description FAR 121, 200nm range

    Design range for given

    payload [@ LRC]

    5500nm

    Block Performance (given payload, ISA, s.a.)Assumptions: Max payload, LRC speed

    3000 nm Block fuel 82662kg/182147 lb

    Block time 6.58h

    TOGW 477730kg/1053197 lb

    Max Range Block fuel 158308kg/349000 lb

    Block time 11.71h

    TOGW 557010kg/1227976 lb

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    Systems Description

    ATA-21 Air Conditioning

    ECS Overview Fully automated

    3 ECS packages

    4 zones

    2 Ram air scoops

    ECS Location Belly Fairing

    Cockpit / Cabin Pressure

    Control

    Automatic and manual

    Cockpit / Cabin

    Temperature Control

    Automatic and manual

    No. Cabin Control Zones 3

    Press. System Overview Digital controller

    Fresh Air Ratio 4 recirc fans

    Overpress. Valve Diff. 9.1 psi

    Cabin Alt. at Max Alt. 8000 ftCooling Cycle Overview 3 ECS packs

    4-wheel cyc. Machine

    Dual heat exchanger

    Water separator

    ATA 22 - Auto FlightAuto Flight

    Cntrl Descr.

    Digital FCCs

    Flight Director Descr. 1 FD per FCC

    Yaw Damper Descr. Incorporated into

    stability

    Auto Pitch Trim Descr. Trim via CGmanagement (trim

    fuel tanks)ATA 23 - Communications

    Comms System Overview VHF radios, HF data

    radios, multimode

    receiver (MMR), ACPs

    ACARS Standard

    SELCAL Standard

    ATA 24 - Electrical Power

    Main Power Type 270V DC

    Power Distr. Frequency VariableNumber of Main Genrtors 8

    Main Generator Power 200kVA

    Aux. Generator & Power

    (APU)

    200kVA

    Emergency Power Source 4 x PMG (100kVA)

    Main System DC voltage 270V, 28V

    Battery Type & Power Lithium Ion

    Number of Batteries 16

    Extrnl AC or DC Hook-Up DC

    Main Distrbtn System Integrated modular

    avionics, full duplex

    ATA 25 Cargo Compartments

    Cargo Handling System

    Overview

    Rheinmetall Power Drive

    Unit System, central

    maintenance computer

    Internal Loading

    Apparatus

    Ball bearings and

    powered rollersProvisions for

    loading/unloading

    Large cargo doors

    Strengthening around

    doors

    Provisions for unusual

    freight

    None

    Floor loading 2823 kg/m / 1897lb/ft

    Cargo compartment alt 8000 ft

    ATA 27 - Flight Controls

    Flight Control System Electrical

    Aileron Actuation Mthod Two Section, 2 Dual

    power source actuators

    er sectionDescription of Rudder Two Section

    Rudder Actuation Method 2 Dual power source

    actuators per section

    Fixed / Var. Incd. Tail Fixed

    Elevator Actuation Mthd 2 Dual power source

    actuators per section

    Stall Protection Devices Envelope protection inFCS

    Flap System Overview Three section single

    slotted fowler main

    wingFlap (Slat) Deflection -

    Takeoff (Highest)

    Main Wing 20 (40)

    Canard 20 (35)

    Flap (Slat) Deflection -

    Landing Configuration

    Main Wing 40 (35)

    Canard 40 (40)

    HI Lift LE Device 3 panel kruger flaps on

    main wing, 1 panel slaton canard

    HI Lift LE Dev. Actuatn Electrical

    HI Lift TE Device Single slotted

    HI Lift TE Dev. Actuatn Electrical

    Total Number of Roll

    Splers / Flight Splers /

    Ground Splers / Total

    / / / 6

    Spoiler Actuation Electrical

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    ATA 28 - Fuel System

    Tot. Usable Fuel Capac. 287290L / 75894 USG

    Tank Capacity (Wing) 202420L / 53474 USG

    Tank Capacity (centre) 48620L / 12844 USG

    Tank Capacity (canard) 36250L / 9576 USG

    Tank Cap. (Aux.+Trim) 14110L / 3727 USGFuel System Overview Automated fuel

    distribution

    Loctn Aux. Fuel Tanks Outer wing

    Fuel Pump Overview Automatically pumped

    to change weight

    distribution

    Cross-Feed Capability yes

    Single Pt Refuel Capab. yes

    Gravity Refuel Capablty yes

    Location of Fuel Filler

    Ports

    below wing leading

    edge between engines

    ATA 29 - Hydraulic Power

    Hydrlic System Overview N/A no hydraulics

    Hydraulic Bay Location N/A

    Number of Main Systems N/A

    Hydraulic Fluid Type(s) N/A

    Nominal Working Pressure N/A

    Hydraulic Pumps N/A

    Hydraulically Actuated

    Items

    N/A

    ATA 30 - Ice and Rain ProtectionAnti-Ice System Overview Electrical, bleed air

    for nacelles

    Wing Electric heat mats

    Canard Electric heat mats

    V-tail Electric heat matsNacelle Intake 5th stage bleed air

    Probes & Sensors Electric

    Windshield Electrically heated

    2 wipers for rain

    Rain repellent liquid

    ATA 32 - Landing Gear

    Landing Gear Actuation EMA

    Emerg. Extension

    Procedure

    Manual release, gravity

    extensionMain Landing Gear Type Cantilever

    Location of MLG Fuselage and Fairing

    MLG Strut Type Oleo-Pneumatic

    Tire Size - MLG 1.27 m x 0.51 m

    50 in x 20 in

    Tire Pressure - MLG 14.32 bar / 208 psi

    MLG Braking System Carbon brakes, anti

    skid system, EHA

    Nose Landing Gear Type Cantilever

    Spatial Direction for

    Retraction of NLG

    Forwards

    NLG Strut Type Oleo-Pneumatic

    Tire Size - NLG 1.27 m x 0.51 m50 in x 20 in

    Tire Pressure - NLG 13.65 bar / 198 psi

    NLG Steering Overview EHA, controlled by RDCs

    ATA 34 - Navigation

    No. of ADS Computers 2

    Number of AHRS 2 GNADIRS

    STD / OPT GPS STD

    EFIS Displays Overview Pilot: 4 LAD (15.3in

    Number of IRS 3 STD

    STD / OPT EGPWS STDSTD / OPT TCAS STD

    No. Radio Altimeters 2 STD

    STD / OPT HUD STD

    STD/OPT CatIIIa Appr. STD

    STD/OPT CatIIIb Appr. STD

    STD / OPT Autoland STD

    GPWS/Wind Shear Detec STD

    Digital Weather Radar STD

    STD / OPT EVS STD

    STD / OPT MLS STD

    Number of VHF Radios 3 STDNo. of HF Transceivers 2 STD

    No. of ADF Receivers 2 STD

    No. DME Transceivers 2 STDSTD/OPT Mode S Trnspn 2 STD

    STD / OPT Coupled VNAV STD

    RNP Capability 0.3 or better

    Overview of FMS System Integrated terrain

    guidance and on ground

    navigation

    ATA 35 - OxygenOxygen System Overview Crew O2 from cylinder,

    PAX chemical oxygengenerators

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    ATA 36 - Pneumatics

    Pneumatic System

    Overview

    N/A

    Location of Bleed Ports

    and Capacity

    N/A

    Pneumatic Source & Use N/A

    Bleed Leak Detection N/A

    ATA 39 - Electrical / Electronic Panels

    Loc. of Major Elec.

    Components & System

    Main Cabin

    Main Display Panels LCD

    Main Display Size (HxW) 15.3in diagonal 16:9

    GE Aviation LAD

    No. Main Display Panels 4 for Pilot, 3 for

    Assist

    Avionics Suite Designtn TBD

    Avionics Suite

    Manufacturer

    Proprietary

    Avionics Rack Location 1 Rack Rear of Cockpit

    1 Rack Fore of Wingbox

    ATA 49 - Auxiliary Power Unit

    Std / Opt APU STD solid oxide fuelcell

    APU Designation Hybrid 440kW SOFC

    APU Manufacturer NASA/Boeing

    APU Location Tailcone

    APU Reqrd for Dispatch Yes

    APU Operation & Control FADEC

    APU Fire Extinguishing Halon

    APU Max Start. Altitude 41000 ft

    APU Max Oper. Altitude 41000 ft

    ATA 52 Cargo Doors

    Access for

    loading/unloading

    Upper and main deck

    doors on port side

    Lower deck fore and

    aft doors on

    starboard side

    All doors open

    outwards

    ATA 53, 54, 55 & 57 - Structure

    Strctrl Prss. Diffrntl 8.32 psi

    Struc. Life cycle/hrs 120000 hrs

    Structure Overview Mostly compositestructure

    Structure & Material

    Fuselage Frame/Floor

    CFRP / carbon

    sandwich

    Struct. & Material -

    Nacelle / Pylon

    CFRP sandwich /

    Titanium

    Struct. & Material -

    Canard

    CFRP wingbox, GLARE

    leading edge

    Struct. & Material -

    Elevator

    CFRP sandwich

    Struct. & Material -

    Vertical tail

    Carbon sandwich,

    GLARE leading edgeWing Tip Geometry Type Winglet, CFRP

    Struct. & Material -Aileron

    CFRP sandwich

    Struct. & Material - HI

    Lift LE Device

    GLARE

    Struct. & Material -

    Lift TE Device

    CFRP

    Struct. & Material -

    Speed Brakes

    CFRP

    ATA 71-80 - Engine

    Engine Manufacturer Rolls-Royce

    Engine Designation Trent

    Turbofan No. of Stages

    Fan/Boost/Compaxial +

    Compcent//HPT/IPT/LPT

    1/8/6/1/1/5

    Number of Engines 4

    Mounting Point wings

    Max. Takeoff Thrust each

    (Std/HO)

    356kN/80,000lbf

    Flat Rating Temp ISA+15o

    Thrust Reversr Overviw Inboard engines only

    Bypass Ratio 7.4

    Overall Pressure Ratio 39

    TSFC at M0.80, FL 350 0.054kg/N/hr,

    0.53lb/lbf/hrFADEC or DEEC FADEC

    ETOPS Capability N/AExternal Noise, MTOW

    (ICAO Annex 16)

    Takeoff / Stage 3 Limit 92.4 EPNdB / 106 EPNdB

    Sideline / Stage 3 Lim. 89.7 EPNdB / 103 EPNdB

    Approach / Stage 3 Lim. 102 EPNdB / 105 EPNdB

    Cumltv Margn to Stg 3 29.9 EPNdB

    Emissions (ICAO LTO

    cycle)

    NOx 53.5g/kN

    CO 40.9g/kN

    Unburnt Hydrocarbons 4.8g/kN

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    Technical Document 07: Stability & Control

    Group 4F i

    List of AbbreviationsAC Aerodynamic Centre

    ARINC Aeronautical Radios, Incorporated

    ATA Air Transport Association

    CCS Common Core SystemCG Centre of Gravity

    CS Certification Specification

    EFCS Electronic Flight Control System

    EHA Electro-Hydrostatic Actuator

    ELAC Elevator/Aileron Control

    EMA Electro-Mechanical Actuator

    FBW Fly-By-Wire

    FCS Flight Control System

    FCU Flight Control Unit

    FMC Fuel Management Computer

    FMGEC Flight Management Guidance and Envelope Computer

    LVDT Linear Variable Differential Transducer

    MAC Mean Aerodynamic Chord

    MCDU Multi-function Display and Control Unit

    MTOW Maximum Take-off Weight

    MZFW Maximum Zero Fuel Weight

    nm Nautical Mile

    OEI One Engine Inoperative

    RAC Rudder/Aileron Control

    SAG Stability Augmentation

    SEC Spoiler/Elevator Control

    T/O Take-off

    WFP Wing-Fuselage-Pods

    List of SuperscriptsA Airborne at V

    MC

    A

    G Grounded at VMCG

    V Vertical Tail Plane

    WFP Wing-Fuselage-Pods

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    Technical Document 07: Stability & Control

    Group 4F ii

    List of Notations

    Angle of attack

    Local angle of attack

    Sideslip angle

    CW Sideslip angle induced by cross-wind Control surface deflection

    r Rudder deflection

    r max Maximum allowable rudder deflection in normal conditions

    r CW Maximum allowable rudder deflection to counteract cross-wind

    Surfacec Mean chord of control surface

    CH Coefficient of hinge moment

    CH 0 Coefficient of hinge moment at zero incidence and control surface deflection

    CL Coefficient of lift

    CL T/o Coefficient of lift at take-offCM Coefficient of pitching moment

    CN Coefficient of yawing moment

    CT

    Coefficient of thrust

    CY Coefficient of side force

    H Hinge moment

    Kr r =

    la Mean aerodynamic chord of wing

    lV Vertical tail arm

    q Dynamic pressureSc Canard reference area

    SW Wing reference area

    SSurface Area of control surface

    VApp Approach speed

    VCW Cross-wind speed

    VMC Minimum control speed

    Vp Control surface volume

    xCG Longitudinal position of the CG from the nose

    xCG AC Longitudinal position of the CG from the wing AC

    yT Lateral distance to outboard engine

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    Technical Document 07: Stability & Control

    Group 4F iii

    Section Breakdown

    M. Dennison: 7-1

    7-2: All Sections

    7-3: All Sections

    7-4: All Sections

    7-5: All Sections except 7-5-3-1

    B. Hutchinson: 7-5-3-1

    M. Bracewell: 7-6: All Sections

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    Technical Document 07: Stability & Control

    Group 4F iv

    Contents

    7-1 Introduction...............................................................................................................................1

    7-2 Longitudinal Stability.................................................................................................................1

    7-2-1 Canard Sizing and Positioning.......................................................................................1

    7-2-2 Digital Datcom Analysis................................................................................................1

    7-2-3 Nose Wheel Reaction....................................................................................................2

    7-3 Lateral Stability..........................................................................................................................3

    7-3-1 Cross-wind Landing.......................................................................................................4

    7-3-2 Directional Stability.......................................................................................................4

    7-3-3 Yawing Moment on Take-off Run.................................................................................4

    7-3-4 Yawing Moment and Side Force while Airborne...........................................................5

    7-3-5 Final Fin Size..................................................................................................................5

    7-4 Derivative Empennage Sizing.....................................................................................................6

    7-4-1 Canard Sizing for Derivative..........................................................................................6

    7-4-2 Fin Sizing for Derivative................................................................................................6

    7-5 Primary Control Systems............................................................................................................7

    7-5-1 Control Surface Sizing...................................................................................................7

    7-5-2 Control Surface Hinge Moments...................................................................................7

    7-5-3 Secondary Control Systems..........................................................................................8

    7-5-3-1 Trim Fuel..........................................................................................................8

    7-5-3-2 Flap Systems....................................................................................................8

    7-5-3-3 Slat Systems.....................................................................................................8

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    Technical Document 07: Stability & Control

    Group 4F v

    List of TablesTable 7-1: Canard geometry and structural parameters 5

    Table 7-2: Fin sizing parameters 6

    Table 7-3: Fin geometry and structural parameters 9

    Table 7-4: Primary control surface sizes 11

    Table 7-5: Primary control surface hinge moments 11

    Table 7-6: EFCS control laws 13

    List of FiguresFigure 7-1: Graph of maximum static margin against CG position 3

    Figure 7- 4

    Figure 7-3: Canard planform 5

    Figure 7-4: Tail planform 9

    Figure 7-5: Wing actuation system 14

    Figure 7-6: Canard and tail actuation system 14

    Figure 7-7: Flight control architecture 15

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    Technical Document 07: Stability & Control

    Group 4F - 1 - M. Dennison

    B. Hutchinson

    M. Bracewell

    7-1 Introduction

    [1],

    [1]. Applying these definitions to an aircraft shows that, in the design stages, it must beensured that the aircraft will resist undesired changes in attitude and position whilst still allowing

    the pilot to implement desired changes. This document outlines the measures taken during design to

    ensure that Colossus remains both stable and controllable.

    7-2 Longitudinal Stability

    Longitudinal stability is the aspect of stability concerned with displacements and attitudes in the x-z

    plane, primarily changes in altitude and pitch angle. While both the main wing and canard have

    bearing on the longitudinal stability of the aircraft, it is the canard that can most feasibly be

    designed to ensure stability, with the main wing being primarily designed as a lifting, rather thancontrolling, surface.

    The aircraft has been designed with the intention that the longitudinal stability will meet CSs 25.171,

    25.173 and 25.175 of Certification Specifications for Large Aeroplanes [2].

    7-2-1 Canard Sizing and Positioning

    The horizontal tail sizing technique outlined in the aerodynamics, stability and control section of the

    design manual [3] is not suitable for this configuration. This is due to the assumption that during

    flight, CG will move backwards as fuel is burnt. However, for a canard configuration, the CG movesforwards as fuel is burnt and so the take-off rotation parameter - usually one of the key sizing

    parameters - does not apply. Therefore, a different sizing procedure had to be adopted for the

    canard.

    Review of literature on canard sizing suggested that, although a canard wing area equivalent to 25%

    of the wing area was ideal to minimise drag [4], canards with more than 15% wing area tended to be

    overly destabilising. Therefore, an initial canard size of 15% wing area was selected as a compromise

    between requirements for low drag and static stability. Further analysis showed that reduction of

    the canard area to only 14% of the main wing area produced a reduction in induced drag as well asdecreasing the destabilising influence of the fore-plane.

    It had previously been noted that the wake from the canard would have an effect on the lift

    distribution of the main wing. To prevent the effect of the wake being too great, the longitudinal

    separation of the two lifting surfaces was maximised such that the downwash from the canard

    would pass well below the flow field generated by the main wing, thereby limiting or eliminating any

    interaction between the two surfaces.

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    Technical Document 07: Stability & Control

    Group 4F - 2 - M. Dennison

    B. Hutchinson

    M. Bracewell

    7-2-2 Digital Datcom Analysis

    Using the aircraft geometry data, along with aerofoil section and surface planform data, an

    approximate model of the aircraft was constructed. The input file is simple and, as such, the

    geometry of Colossus had to be vastly simplified in order for the model to be run. While this reduced

    the veracity of the model, the data produced is still more accurate than hand calculations as, thesource data being empirical, effects such as viscosity and vorticity are accounted for. The

    assumptions made in the construction of the fuselage model were that the constant diameter

    section of the fuselage was cylindrical with a diameter equal to the height of the real fuselage and

    that the nose and tail cones were not curved, but simple cones. The wings and canard, instead of

    having twist and thickness distributions that vary non-linearly along the span, were assumed to be in

    two panels, each with linear thickness and twist distributions. Also, features such as the

    undercarriage sponsons, engine nacelles and flap tracks could not be modelled, and neither could

    the effect of deployed flaps. Although the database did not include data for the aerofoil sections

    used for the wing and canard, the inbuilt vortex panel solver could calculate the sectionalcoefficients given the coordinates of the aerofoil surface. The Datcom input file used can be seen in

    Appendix A.

    A Digital Datcom analysis of this model was then run. From this computation, it was possible to

    ascertain the variation of several

    importantly from a stability perspective, the values of

    CM

    and

    CL

    were calculated at a range of

    C

    C-LM

    produces a graph of static margin variation with angle of

    attack. Using this, and varying the input CG position, it is possible to ascertain the foremost and

    rearmost CG positions that keep the static margin within a certain range for a given range of flight

    conditions.

    7-2-3 Static Margin and Allowable CG Range

    The static margin range that has been selected is 5% to 35% MAC. The rear limit, 5% MAC, has been

    selected as this is the conventional safety margin applied to ensure that the aircraft remains

    statically stable. The forward limit has been selected to produce an allowable CG range of

    comparable size to competitor aircraft. It was felt during design that one of the crucial parameters

    for producing a viable freighter aircraft was that there had to be at least some freedom of cargo

    positioning, and therefore cargo CG position. Producing an aircraft with a more restricted static

    margin - and therefore centre of gravity position - was felt to have a greater impact on freighter

    operations than having a potentially more than desirably stable aircraft. In addition, the large

    moment arm to the canard control surfaces and high power of the lifting surfaces mounted there

    were felt to ameliorate the risk that the aircraft would be less controllable than comparable aircraft.

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    Technical Document 07: Stability & Control

    Group 4F - 3 - M. Dennison

    B. Hutchinson

    M. Bracewell

    -0.4

    -0.2

    0.0

    0.2

    0.4

    0.6

    0.8

    35 37 39 41 43 45

    CG Position (m)

    Max.

    StaticMarg

    in(%MAC)

    Figure 7-1: Graph of maximum static margin against CG position

    This static margin range corresponds to an allowable CG range of between 39.26m and 41.5m from

    the nose of the aircraft. Fig. 7-1 shows how maximum static margin increases as CG moves towards

    the nose. If the CG moves further forward than 39.26m from the nose, the maximum static margin

    becomes too large, as can be seen in the figure. The result of an increasing static margin is that the

    aircraft starts to become overly stable, r ,

    eventually preventing crucial manoeuvres such as flaring, thereby presenting a danger to the

    aircraft. Conversely, if the CG moves aft more than 41.5m from the nose, the angle of attack at

    which the static margin drops below 5% becomes too small and it becomes dangerous to perform

    pitch manoeuvres as they may cause the aircraft to become unstable.

    Fig. 7-2 displays the variation of static margin with angle of attack for the 5500nm design missionwith 175t payload. As can be seen, the static margin reduces with angle of attack, up to a point, after

    which it increases again. This effect is created purely by the flow interaction of the canard wake with

    the wing lifting field. As the turbulent flow from the canard impinges on the wing, it decreases the

    magnitude of the nose-down pitching moment generated by the wing, reducing the ability of the

    aircraft to recover from pitch disturbances. However, above angles of attack greater than 11 at

    cruise, the wake passes over the top of the wing, rather than impacting directly on it. This reduces

    the effect of the interaction again. It should also be noted, however, that the interaction only causes

    a reduction in static margin below the acceptable 5% MAC at around 9 at take-off, 8 at

    cruise and over 10 on landing. These angles of attack are greater than those at which the aircraftoperates in any of these mission phases. It can therefore be stated that the aircraft will remain

    statically stable at any mission phase, even without the assistance of a stability augmentation

    system.

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    -0.1

    -0.05

    0

    0.05

    0.1

    0.15

    0.2

    0.25

    0.3

    0.35

    0.4

    -5 0 5 10 15

    StaticMargin(%MAC

    )

    Take-Off Cruise - First Stage Cruise - Second Stage Cruise - Third Stage

    Cruise - End Approach Zero Fuel Landing

    Figure 7-2

    7-2-4 Nose Wheel Reaction

    In addition to the airborne stability calculations, it was necessary to ensure that the reaction load

    produced at the nose wheels was acceptable. The load on the nose wheels cannot be allowed to

    exceed 15% of the MTOW of the aircraft, as this makes the aircraft both difficult to steer on the

    ground and more prone to nose wheel slam or collapse on landing. It also cannot be allowed to be

    less than 5% of the MTOW of the aircraft, as this would give insufficient tire friction for effective

    steering.

    The undercarriage has been designed with these parameters in mind. The two critical cases for the

    nose wheel reaction are when the aircraft is at MZFW and at MTOW, as these are when the CG is at

    its most forward and aft positions respectively. When the aircraft is at its MTOW, the allowable CG

    range is between 40.62m and 44.35m from the nose, relating to 15% and 5% nose wheel reaction

    respectively. The CG position when the aircraft is at MTOW, as produced by the weights and balance

    team, is 40.785m from the nose [5]. When at MZFW, the allowable CG range is between 37.86m and44.35m from the nose, while the actual CG position is at 39.51m from the nose. As can be seen, the

    actual CG positions are both within the allowable CG ranges. It is important to note that the

    allowable CG ranges described here do not apply while the aircraft is airborne, only when the full

    weight of the aircraft is being supported by the undercarriage. For discussion of the design and sizing

    of the undercarriage, see Technical Report 3: Structures [6].

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    7-2-5 Final Canard Sizing

    Details of the canard geometry and structural parameters can be found in Table 7-1 and the

    planform of the canard can be seen in Fig. 7-3.

    Part Item STD

    Canard

    (Reference)

    Span 25.5m / 83.7ft

    Area 111m2 / 1195ft2

    Aspect Ratio 5.87

    Anhedral 0

    Quarter Chord Sweep 35

    Taper Ratio 0.3

    Mean Aerodynamic Chord 4.76m / 15.62ft

    Quarter chord MAC from fuselage nose 12.23m / 40.12ft

    Quarter chord MAC height 2.49m / 8.17ft

    Lateral MAC location 5.23m / 17.16ftthickness/chord ratio: root, tip 0.14, 0.105

    Spar location (% chord, front / rear) 15% / 70%

    Fuel Volume (net) 36250L / 9576 USG

    Table 7-1: Canard geometry and structural parameters

    Figure7-3: Canard Planform

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    7-3 Lateral Stability

    Lateral stability analysis was performed with the purpose of ascertaining the necessary size for the

    vertical tail in order to maintain directional stability despite various perturbing influences. Each of

    these influences has been considered as an individual sizing case. The fin has been sized to meet all

    cases.

    The aircraft has been designed with the intention that the lateral stability will meet CSs 25.177 and

    25.181 [2].

    The following parameters have been used in the calculation of the required fin size. The lateral

    derivatives have been assumed to be equal to those of the reference aircraft, the Airbus A330. The

    rudder effectiveness factor has also been assumed to be equal to that of the A330, and linear

    interpolation has been applied between the data points to give a value of Kr at any rudder

    deflection.

    Main Wing Area (SW) 680m2

    Wing Mean Aerodynamic Chord (la) 10.11m

    Span-wise Position of Outboard Engine (yT) 25.70m

    Longitudinal Position of rearmost CG relative to Wing AC (xCG AC) -7.65m

    Tail Arm (lV) 27.42m

    CyWFP

    / -0.43

    CyV/ -3.726

    CyV

    /r 1.892CN

    WFP/ -0.462

    Minimum Airborne Control Speed (VMCA) 72.02m/s

    Minimum Ground Control Speed (VMCG) 72.02m/s

    Approach Speed (VAPP) 79.74m/s

    Cross-wind Speed (VCW) 12.86m/s

    Lift Coefficient at Take-off (CL T/O) 2.604

    Thrust Coefficient at VMCA

    (CTA) 0.1647

    Thrust Coefficient at VMCG (CT

    G) 0.1647

    Windmill Drag Coefficient at VMCA

    (CD WMA

    ) 0.0013Windmill Drag Coefficient at VMC

    G(CD WM

    G) 0.0013

    0.0873rads

    Maximum Rudder Deflectior max) 0.5236rads

    Maximum Rudder Deflection in Cross-r CW) 0.3665rads

    Rudder Effectiveness Factor at 30 (Kr 30) 0.900

    Rudder Effectiveness Factor at 21 (Kr 21) 0.996

    Table 7-2: Fin sizing parameters

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    7-3-1 Cross-wind Landing

    The fin must be sufficient in size such that the aircraft is capable of maintaining a straight flight path

    on landing when subject to a 25 knot (12.86 m/s) cross-wind. The cross-wind induces a side-slip

    CW) as calculated below.

    )V

    V(tan=

    App

    CW1CW

    The re CW is 0.1599. Using this value and the parameters listed in Table 7-2, the

    equation below can be used to work out the required fin area ratio such that the aircraft can

    maintain a straight approach in a cross-wind.

    a

    v

    r

    V

    Y

    V

    Y

    CWa

    ACCG

    WFP

    Y

    WFP

    N

    l

    l

    rr

    C

    CW

    C

    l

    x

    C

    C

    v

    )K+(

    )0.25-+(=

    S

    S

    For this case, the required fin area ratio is 0.001335.

    7-3-2 Dynamic Stability

    The dynamic lateral stability of an aircraft is usually determined by the qualities of the Dutch Roll

    mode at low speeds. However, this involves complex analysis involving nine lateral derivatives and

    mass distributions throughout the airframe. Therefore, the fin should be sized to provide an

    acceptable level of directional, or weathercock, stability. To achieve this acceptable level, whereby

    the aircraft recovers from changes in sideslip angle, the value of C should be greater than 1.25 [3].

    Using this and the parameters in Table 7-2, the required fin area ratio can be calculated, using the

    equation below.

    )-25.0+(

    C-)0.25-(-=

    S

    S

    a

    CG

    a

    v

    V

    Y

    a

    ACCGWFP

    Y

    WFP

    N

    l

    x

    l

    l

    C

    Nl

    x

    C

    C

    V

    For this case, the required fin area ratio is 0.1548.

    7-3-3 Yawing Moment with OEI on Take-off Run

    It is a requirement that the fin be capable of reacting the unbalanced yawing moment produced in

    the case of one engine failing on the take-off run. This assumes that the undercarriage provides no

    side force reaction. The engine that fails produces windmill drag and does not produce thrust to

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    balance the thrust produced by the corresponding engine on the opposite wing. The equation below

    calculates the fin area ratio necessary to react this yawing moment.

    r

    C

    l

    l

    )C+C(

    V

    K)(=

    SS

    r

    V

    Y

    a

    V

    r

    alTyG

    WMD

    G

    T

    The fin area ratio required for this sizing case is 0.1364.

    7-3-4 Yawing Moment and Side Force with OEI while Airborne

    When the aircraft is airborne, it is able to both yaw and translate in the lateral plane. Therefore,

    equations relating the fin size to yawing moment and side force must be solved together to ensure

    that the aircraft reaches a state of equilibrium. Also, unlike the other cases, it is permissible for theaircraft to assume a roll angle, assisting the reaction at the tail fin with a component of the lift force.

    In order that the aircraft reach a state of equilibrium, the two equations below must be solved

    simultaneously forS

    SV ideways component of the unbalanced

    thrust and drag to the side force generated by the fin, while the second equation relates the yawing

    moments produced by the unbalanced thrust and drag to the reaction moment at the vertical tail.

    rr

    C

    C

    C

    LV

    K+

    -C-=

    S

    S

    r

    V

    Y

    V

    Y

    WFP

    Y

    )K-(

    )C+(C-))25.0-(+(=

    S

    S

    rr

    C

    C

    l

    l

    l

    yAWMD

    ATl

    x

    C

    C

    V

    r

    V

    Y

    V

    Y

    a

    V

    a

    t

    a

    ACCGWFP

    Y

    WFP

    N

    The result of solving these two equations is that a fin area ratio of 0.1601 is required.

    7-3-5 Final Fin Sizing

    The largest fin area ratio required by the sizing cases was 0.1601, required to maintain the aircraft in

    equilibrium while airborne at VMCA

    when one engine failed. When multiplied by the reference wing

    area, the reference area of the vertical fin is calculated as 108.86m2.

    Although the planform of the A330 tail is provided [3], it was not felt to be suitable for

    implementation on Colossus. The relatively large size of the tail meant that if the A330 planform had

    been adopted, the root chord of the fin would have been over 15m and the structure at the root

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    could impinged on cargo volume. Because of this, it was decided to adopt a planform with a smaller

    root chord. The height was kept constant and the tip chord increased in order to maintain a constant

    area. The selected fin planform is described in Table 7-3 and shown in fig. 7-4.

    Part Item STD

    Vertical Tail

    (reference)

    Area (including rudder) 108.86

    Aspect ratio 1.33

    Quarter chord sweep 40.7

    Taper ratio 0.5

    Mean Aerodynamic Chord 9.5275

    Quarter chord MAC from fuselage nose 68.41

    Quarter chord MAC height 5.045

    Tail arm 24.71

    Tail volume 2689.93

    Spar location (% chord, front /rear) 15% / 65%

    Thickness to chord; root / tip 10% / 10%

    Table 7-3: Fin geometry and structural parameters

    Figure 7-4: Tail Planform

    7-4 Derivative EmpennageConsideration has been taken of the possibility of having to re-size the empennage if the proposed

    higher payload derivative is to be put into service. The results of this consideration are detailed here.

    7-4-1 Canard Sizing for Derivative

    Since the plan for the derivative aircraft, the Colossus-200, is for fuselage plugs to be inserted

    forward of the canard and aft of the wing, the distance between the canard and wing will be

    identical to that of the original aircraft. This will mean that although the stretched version will

    exhibit a reduced range and performance, the canard should not need to be re-sized to maintain

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    stability. The addition of mass in front of and behind the centre of gravity should also mean that the

    CG position does not move very far. This should mean that the static margin for the derivative is

    similar to the original aircraft. With the increase in fuselage length, it may be possible to increase the

    size of the forward trim tank, described in section 7-5-3-1 to provide greater control over the CG

    position in flight, further reducing the need for changes to the sizes or positions of the aerodynamicsurfaces.

    It is worth noting that, were a lower-payload, shorter-fuselage derivative to be proposed, then the

    canard sizing would have to be considered to ensure that the aircraft was both stable and not

    susceptible to increased interactions between the wing and canard flow fields. However, no reduced

    payload derivative is being proposed, and such consideration is therefore pointless.

    7-4-2 Fin Sizing for Derivative

    Increasing the length of the fuselage in order to accommodate more payload will increase themagnitude of the WFP derivatives in the lateral stability equations, which would suggest that the fin

    will become undersized for the derivative. However, another effect of increasing the length of the

    fuselage, specifically between the centre of gravity and the fin, is that the tail arm will increase. This

    increase in the tail arm and, consequently, the moment that can be produced by the fin, will

    outweigh the effect of the increase in destabilising WFP terms. Therefore, the fin for the Colossus-

    200 will not have to be increased in size over the original aircraft fin.

    If a reduced payload derivative with a shorter fuselage were to be proposed, the inevitable

    reduction in tail arm would most likely necessitate an increase in fin size.

    7-5 Control Surface Sizing

    It is vital that the control surfaces be sufficient to provide the pilot with enough authority over the

    motions of the aircraft and that the actuation systems be sufficient to ensure that the control

    surfaces are always capable of achieving the deflections specified by the pilot or flight control

    system.

    7-5-1 Primary Control Surface Sizing

    The control surfaces on Colossus have been sized empirically using the data provided in the design

    handbook [3] for the reference aircraft, the Airbus A330. The span-wise position of the surfaces has

    been altered slightly, mainly in the case of elevators on the canard which had to be reduced in span

    relative to the elevators on the A330 tail. This was due to the need for there to be powerful high-lift

    devices on the canard to counteract the pitching moment produced by the wing-mounted high-lift

    devices. For more on the design of the high-lift devices, see Technical Report 5: Aerodynamics [7]. It

    was decided that the span of the elevators could be reduced, as long as the trailing edge of the

    canard remained fully moveable. Since the reduction in span was to make way for flaps, this was

    found to be acceptable. The flaps will be deployed at take-off and landing, reducing the lift increase

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    required from the elevators, allowing the elevator deflection to be reduced. With the elevators not

    at their maximum deflection, there is still a reserve of control power for rapid pitch changes, such as

    go-around manoeuvres. The position and size of the primary control surfaces is shown in Table 7-4.

    The percentages given in the span limit columns refer to percentage semispan.

    SurfaceHinge Line Position

    on ChordInboard Span Limit Outboard Span Limit Area

    Elevator 70%7.87m / 25.82ft

    (62%)

    12.75m / 41.83ft

    (100%)4.238m

    2/ 45.62 ft

    2

    Aileron 76%28.13m / 92.27ft

    (75%)

    35.63m / 107.04ft

    (95%)9.608m

    2/ 103.4 ft

    2

    Rudder 70%0.6025m / 1.98ft

    (5%)

    11.45m / 37.57ft

    (95%)29.40m

    2/ 316.5 ft

    2

    Table 7-4: Primary Control Surface Sizes.

    7-5-2 Primary Control Surface Hinge Moments

    The control surface hinge moments were calculated using the procedure outlined in the design

    manual [3]. The values of CH0,'

    CH

    and

    CH

    provided there for the reference aircraft, the A330, were

    surfaces using the equations below. In each case, the worst cases of local incidence and control

    surface deflection have been taken to ensure that the actuators cannot be overloaded in normal

    operation. The results of the calculations, along with the data used to produce them, are shown in

    Table 7-5.

    pHVqC=H

    where:

    SurfaceSurfacep

    HH

    0HH

    cS=V

    C+'

    '

    C+C=C

    Surface CH0 Deflection Hinge Moment

    Elevator -0.0064 -0.0595 -0.30230 -10940Nm / -8069lbf-ft

    -15 5280Nm / 3894lbf-ft

    Aileron -0.0758 -0.1 -0.586325 -72640Nm / - 53570lbf-ft

    -25 41260Nm / 30430lbf-ft

    Rudder 0 0.117 -0.43 30 371100Nm / 273700lbf-ft

    Table 7-5: Primary Control Surface Hinge Moments

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    7-5-3 Secondary Control Systems

    Secondary controls are those that are not used for short-term changes to the aircraft position or

    attitude. They are instead used to make protracted changes to the aircraft dynamics either by

    affecting the CG position in the case of trim tank systems or by significantly affecting the lift and drag

    characteristics of lifting surfaces in the case of spoilers, slats and flaps. They usually take longer todeploy or retract, hence not being used for instantaneous or short-term control demands.

    7-5-3-1 Trim System

    There will be a 36.25 tonne fuel tank built into the canard box to aid aircraft stability. Without this

    trim tank, the centre of gravity would drift forwards as fuel in the wing was burned. The solution is

    to start with the canard fuel tank full, and as the fuel in the wing is burned, pump the canard fuel

    backwards. This will offset the centre of gravity drift.

    Fuel flow will be controlled by the Fuel Management Computer (FMC). The FMC will calculate exactly

    how much fuel must be pumped back, the rate it should be pumped at and when it should be

    pumped. Valves in the fuel flow pipes will be utilised for flow control; the valves themselves will be

    controlled by the FMC.

    7-5-3-2 High-Lift SystemThe high-lift system implemented on Colossus features high-lift devices on both the canard and main

    wing. The leading edge of the canard has plain slats to 95% semispan while the inner 50% of the

    trailing edge of the exposed semispan it devoted to double-slotted Fowler flaps. The wing features

    Kruger leading edge flaps over 85% of the semispan with breaks for the pylons and single-slotted

    Fowler flaps to 70% semispan. For further discussion of the design of the high-lift system, see

    Technical Report 5: Aerodynamics (Reference 7) and for the actuation methods employed, see

    section 7-6-2 below.

    7-6 Flight Control System (FCS)

    The flight control section can be categorised into three sections: the architecture, the control laws

    and the actuation methods. All three sections are examined here and in more detail in the Systems

    Specialist Report.

    7-6-1 Electronic Flight Control System (EFCS)

    The EFCS is fully integrated into the common core system (CCS) onboard Colossus. The system is a

    fail operational design, as there is no manual reversion available for the system. The EFCS controls

    the aircraft in roll, pitch and yaw through five cross coupled control processes:

    1. Elevator/Aileron Control (ELAC)

    This process controls the elevator position and the aileron channel. Control of both

    pitch and roll, with secondary control of yaw through asymmetric deployment of the

    ailerons and elevators.

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    2. Spoiler/Elevator Control (SEC)

    Controls the spoiler deployment on the main wing, along with secondary control of

    the elevators. This process can control the aircraft in pitch and roll.

    3. Rudder/Aileron Control (RAC)

    Manages the rudder control channel, along with secondary control of the aileron

    actuators.

    4. Flight Augmentation Computer (FAC)

    Damps unwanted oscillations in the aircraft, such as dutch roll through the yaw

    damper and through the primary control surfaces.

    5. Stability Augmentation (SAG)

    This function monitors the attitude of the aircraft and augments the longitudinal

    stability of the aircraft. It has input into the elevators and the fuel management

    system to limit the motion of the centre of gravity.

    The EFCS implements three different sets of control laws depending on system health.

    Normal laws are applied when system health is at 100%.

    Alternate law sets are applied if the system performance degrades.

    Direct law is used in the event of further system degradation.

    This combination of Alternate and Direct law ensures that the EFCS initially fails operational, and

    upon compounding failures, fails safe. The details of each law set are shown in table 7-6.

    EFCS Control Law Set Services and Limits

    Normal Dynamic Envelope protection : pitch limit, roll limit, overspeed

    protection

    Dynamic Load factor protection: pitch rate, roll rate.

    Stall protection

    Auto turn co-ordination

    Flap/Gear down speed limiting

    Dutch roll damping

    Phugoid motion damping

    Alternate Fixed Envelope protection : max pitch attitude, max roll angle, max

    speed

    Direct Direct control coupling to control sidestick, no envelope protection.

    Table 7-6: EFCS Control Laws

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    7-6-2 Flight Control Actuation System

    The flight control system is an electrically signalled, electrically powered system, with position

    sensing feedback to the EFCS and pilot. The system uses a combination of electromechanical

    actuators (EMAs) and electro-hydrostatic actuators (EHAs).

    Fig. 7-5 shows the actuation system for the main wing, and fig. 7-6 shows the actuation system for

    the canard and tail.

    Figure 7-5: Wing actuation system

    Figure 7-6: Canard and Tail Actuation System

    Flap

    Flap

    Ailerons

    Kruger Flap

    Flap

    Spoiler

    SpoilerSpoiler

    E

    M

    AE

    M

    A

    E

    M

    AE

    M

    A

    E

    M

    A EM

    A

    E

    M

    A

    E

    M

    A EM

    A

    E

    M

    A EM

    AE

    M

    AE

    H

    A

    E

    H

    A

    E

    H

    A

    E

    H

    A

    E

    M

    AE

    M

    AE

    M

    A

    E

    M

    AE

    M

    AE

    M

    A

    Kruger Flap

    Kruger Flap

    Primary Power Source

    Secondary Power Source

    Colour corresponds to power bus, i.e.

    red, blue yellow or green 270V DC bus

    bar.

    TAIL

    EHA

    EHA

    EHA

    EHA

    Primary Power Source

    Secondary Power Source

    Colour corresponds to power bus,

    i.e. red, blue yellow or green 270V

    DC bus bar.

    Flap

    Slat

    CANARD

    Elevator

    Flap

    E

    H

    AE

    H

    A

    E

    H

    AE

    H

    A

    E

    M

    A

    E

    M

    A

    E

    M

    A

    E

    M

    A

    E

    M

    AE

    M

    A

    Rudder

    Rudder

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    The primary flight controls (the elevators, ailerons and rudder) are all actuated using EHAs. The

    secondary control surfaces and high lift devices (slats, flaps and spoilers) are actuated using EMAs.

    Each control surface is actuated by two, dual power source actuators. This provides each actuator

    with a quad redundancy, ensuring that if there is power on any main bus bar (probability of nopower on any bus bar 9.45 x 10

    -26(Reference: Systems Report, Power Systems) which is the

    probability of catastrophic failure of the electrical) one actuator per surface will be powered. This

    results in very high system reliability, and allows the reduction in the number of tail and aileron

    segments, reducing the number of actuators required and so increasing efficiency.

    7-6-2 Flight Control Architecture

    The control of Colossus is achieved through two closed control loops. The fly-by-wire flight

    control loop, and an autoflight / navigation control loop through the Flight Management

    Guidance and Envelope Computer (FMGEC). This control architecture can be seen in figure 7-7.

    Figure 7-7: Flight Control Architecture

    The fly-by-wire control system (FBW) incorporates the EFCS control laws, and combines the pilot

    input demands under manual flight, or the FMGEC commands in autoflight. The FBW computer then

    calculates the correct control inputs for the actuators, through the ELAC, SEC, RAC, FAC and SAG

    processes.

    These control demands are transferred to the actuator controllers via an ARINC 629 data bus. The

    control loop is closed via a feedback loop using various sensors, such as Linear Variable Differential

    Transducers (LVDTs) and other sensors to determine the actuator position and return the data to the

    FBW processes in the CCS via the flight ARINC 629 databus. The sensed position and demanded

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    position are compared and the FBW computer then recalculates a new control signal, taking into

    account new demands from the pilot or FMGEC.

    The reliability of the system is ensured through a combination of the multiple redundancies within

    the FBW Actuator control loop, and the CCS architecture. The FBW computer uses 5 processes whichare all cross coupled, ensuring that the failure of a single process does not compromise the control

    loop. Furthermore, the avionics architecture onboard Colossus (Dual flight data busses, Dual CCS)

    ensures that the backup architecture will monitor and if necessary replace the primary FBW

    computer. This dual redundancy along with the inherent redundancy in the CCS provides a FBW

    system that can incur multiple failures without significant performance degradation, effectively the

    system will fail operational twice (i.e. each FBW computer on each CCS must experience faults)

    before the alternate laws for the EFCS are used.

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    Technical Document 07: Stability & Control

    Group 4F - 17 - M. Dennison

    B. Hutchinson

    M. Bracewell

    References

    1: Oxford English Dictionary

    http://www.oed.com/

    Date last accessed: 22/02/08

    2: Certification Specifications for Large Aeroplanes CS25

    www.easa.europa.eu/doc/Agency_Mesures/Agency_Decisions/CS-25_Amdt4.pdf

    Date last accessed: 22/02/08

    3: 2008 Design Handbook Section 7: Aerodynamics, Stability and Control

    University of Bristol/Airbus UK

    4: Aircraft Design: A conceptual Approach - Fourth Edition

    Daniel P. Raymer. AIAA Education Series, New York: 2006

    5: Technical Report 4: Weights and Balance

    T. Petzold, P. Gallagher and M. Smallwood

    6: Technical Report 3: Structures

    P. Gallagher, M. Smallwood and T. Petzold

    7: Technical Report 5: Aerodynamics

    D. Mansell and M. Dennison

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    Technical Document 07: Stability & Control

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    Appendices

    A: Digital Datcom Input FileCASEID APPROXIMATE COLOSSUS

    $FLTCON NMACH=1.0,MACH(1)=.235,ALT(1)=478,NALPHA=13.0,

    ALPHA(1)=-5.,-2.5,0.,2.,4.,6.,8.,10.,12.,14.,16.,18.,20.,$

    $OPTINS SREF=680.0,CBARR=10.11,BLREF=75.0,$

    $SYNTHS XCG=40.883,ZCG=0.0,XW=7.0,ZW=-3.75,ALIW=3.0,

    XH=35.74,ZH=4.75,ALIH=3.0,XV=60.86,ZV=4.75,$

    $WGPLNF CHRDR=6.68,CHRDTP=2.00,SSPN=12.75,SSPNE=12.00,

    SAVSI=35.0,CHSTAT=0.0,TWISTA=-4.0,DHDADI=0.0,TYPE=1.0,$

    $WGSCHR TYPEIN=1.0,NPTS=15.,

    XCORD(1)=0.,0.001,0.002,0.01,0.1,0.2,0.3,0.4,0.5,0.6,0.7,0.8,0.9,0.95,1.,

    YUPPER(1)=0.,0.0062,0.0086,0.0175,0.0415,0.0510,0.0554,0.0566,

    0.0552,0.0513,0.0441,0.0323,0.0154,0.0051,-0.00755,

    YLOWER(1)=0.,-0.0062,-0.0086,-0.0175,-0.0415,-0.0511,-0.0556,-0.0564,

    -0.0526,-0.0428,-0.0270,-0.0092,-0.0004,-0.0023,-0.00755$

    $HTPLNF CHRDTP=3.74,CHRDR=14.4,SSPN=37.5,SSPNE=34.57,

    SAVSI=33.0,CHSTAT=0.0,TWISTA=-4.0,DHDADI=-2.0,TYPE=1.0,$

    $HTSCHR TYPEIN=1.0,NPTS=15.,

    XCORD(1)=0.,0.001,0.002,0.01,0.1,0.2,0.3,0.4,0.5,0.6,0.7,0.8,0.9,0.95,1.,

    YUPPER(1)=0.,0.0066,0.00912,0.0186,0.0440,0.0541,0.0587,0.06,0.0586,0.0544,

    0.0467,0.0342,0.0163,0.0054,-0.008,

    YLOWER(1)=0.,-0.0066,-0.00912,-0.0186,-0.0440,-0.0542,-0.0589,-0.0598,-0.0558,-0.0454,

    -0.0286,-0.0097,-0.0004,-0.0024,-0.008$

    $VTPLNF CHRDR=12.1,CHRDTP=6.02,SSPNE=12.0,SSPN=12.05,

    SAVSI=35.0,CHSTAT=0.0,TWISTA=0.0,TYPE=1.0,$

    NACA-V-4-0010

    $BODY NX=5.0,

    X(1)=0.,8.0,30.0,68.0,78.0,

    R(1)=0.,3.55,3.55,3.55,0.,

    ZU(1)=0.0,0.0,0.0,0.0,0.0,$

    DERIV DEG

    DIM MNEXT CASE