Upload
osborne-hunt
View
231
Download
9
Embed Size (px)
Citation preview
Mine Counter MeasureusingMEA
Background: Rapid Airborne Mine Clearance System (RAMICS)
• RAMICS– The Rapid Airborne Mine Clearance System (RAMICS) is one of four airborne mine countermeasures systems
– A laser-imaging, helicopter-borne gun system, designed by Northrop Grumman Corporation for the U.S. Navy to destroy mines at sea, fires at underwater targets with a 30mm MK44 Bushmaster II cannon manufactured by ATK Armament Systems
– The 30mm MK44 Bushmaster II cannon fires a supercavitating round ( MK258 Armor Piercing, Fin Stabilized, Discarding Sabot-Tracer {APFSDS-T} Anti-Mine Projectile Hydroballistic Ammo 30mm Ammunition). Unlike conventional projectiles that lose velocity upon hitting water, a supercavitating round has a unique configuration allowing it to maintain velocity, direction and kinetic energy, after entering water, to destroy a mine upon impact
– RAMICS is designed to obtain target data from another Northrop Grumman mine countermeasures product: the Airborne Laser Mine Detection System (ALMDS)
• Problems– Requires use of helicopter-mounted 30mm MK44 Bushmaster II cannon which helicopters are not designed to
fire as there is too much recoil
– Helicopter platform is required as supercavitating rounds used by RAMICS need at least a 50 degree elevation to maintain its velocity upon entering water
Airborne Laser Mine Detection System (ALMDS)
• ALMDS– North Grumman received a $27M contract to
upgrade and modify the ALMDS– The AN/AES-1 ALMDS is the first airborne organic
mine countermeasure system designed to:• Detect • Classify• Pinpoint floating and near surface moored
mines• Use light detection and ranging (LIDAR)
– Aspects of the mine countermeasure mission package are found on the Navy’s new LCS
– Deployed on the MH-60 helicopter
The MH-60S• The ALMDS is integrated into the MH-60S helicopter to
provide a rapid wide area reconnaissance and assessment of mine threats in mainly confined straits or choke points
• The MH-60S deploys the AQS-20A Mine Detection System and an Airborne Laser Mine Detection System (ALMDS) for identifying submerged objects in coastal waters
• ALMDS is used for the mine countermeasures (MCM) on the new Littoral Combat Ship (LCS).
Archerfish Airborne Mine Neutralization System
• The system is designed to work in concert with sonar systems. The sonar systems localize and identify sea mines, after which the AMNS reacquires and destroys the mines with a self contained shaped charge.
• MH-60S aircrews will utilize the Archerfish neutralization system to remotely navigate to the target from the helicopter using information gained from the systems onboard sonar and ultimately its camera while in close proximity to its intended target. After the neutralizer reaches its target, the operator initiates the burning of the shaped charge, which destroys the target.
• It cost around $100K to destroy a mine
Cost Effective Solution:Rapid Airborne Mine Neutralization System with the .50 cal
MG/MEA or a 20mm Gun/MEA
M.E.A. - Multi Environment Ammunition(The 12.7mm APSX) or 20mm MEA
Current Ammo• Problems with current (standard) ammo
– Conventional rounds fired from the air do not work in water. Trying to defend against water-borne attacks , such as swarming boats, where rounds have to penetrate water barriers, such as waves, to hit a target is futile.
– Conventional rounds in route to a target, instead of entering the water, may ricochet off the water’s surface, losing velocity and also proving futile against swarm attacks
– Destroying mines and defending against swarming surface attacks are excellent applications of supercavitating rounds
– While various forms of supercavitating ammunition have existed for many years, they have major drawbacks:
• require steep angle of water entry (>60 degrees) – so unsuitable for firing from surface vessels
• require fins for stable flight, so much larger caliber weapon needed (30mm cannon to fire 9mm dart – RAMICS)Core Cavity boundary
Why MEA?• The US Navy needs new rounds for the RAMICS• The RAMICS program limitations due to:
– 30mm cannon needed to fire just 9mm darts– MK258 Armor Piercing, Fin Stabilized, Discarding Sabot-Tracer (APFSDS-T),
Anti-Mine Projectile Hydroballistic Ammo 30mm Ammunition– Requires a Helicopter Platform
• The 12.7 mm APSX MEA is in production in the USA– Can be fired from:
• Ships due to low entry angle• Helicopters – using existing .50 cal weapons• UUVs – Mount .50 cal and fire 12.7 mm MEA
– No need to install heavy 30mm gun• .50 cal or a 20mm gun with MEA can do the job• Lighter, safer and more deployable solution
– Proven in sea trials against real underwater targets
The Most Effective Solutions for Destroying Mines
• The 12.7mm APSX MEA (only requires an ammo change)– Achieve mine destruction with only .50 caliber– Immediately deployable in standard weapons on surface and airborne platforms– Enables use of UUV as re-usable mine countermeasures platform– MEA rounds enter the water without danger of ricocheting even when multiple
air/water entries are involved (i.e. passing through waves)– Are capable of penetrating steel targets underwater at an underwater range up to
60m for 12.7mm– Rapid response clearance capability against near-surface and surface (floating)
moored mines– Higher performance and lower cost compared to older supercavitating rounds– Standoff capability to destroy mines with great speed and accuracy– MEA rounds enter or leave water at very low angles– Currently in production in the USA in 12.7mm and 7.62mm
MEA Features• Low angle water entry• Low angle armor piercing (cylindrical shapes)• Multiple-layer targets• From Air or Water to Air or Water• Calibre-sized holes (depending on application)• Burst Charges capability• Greatly extended range in air (by up to 25%)• Used in standard weapons without modification• Up to 31 times more effective energy transfer to target than MK258 design
(30mm)
20mm >120% standard
12.7mm >2000 m
Calibre Air Range Underwater range
150 metres
60 metres
Detecting Mines at Sea Using Blue/Green Lasers
Rapid Airborne Mine Neutralization System with the M2HB or 20mm
Gun/MEA
System Computes:•True Target Vector
• Slant Range• Gimbal Angles (Roll, Pitch)• Target Angles in FOV
•Boresight Laser Vector• Slant Range to Surface Spot• Spot Angles in FOV
•Line of FireCompensating for:•Geometric Effects•Ballistic Effects•Kinematic Effects
Line of F
ire
Boresight laser
Vector to boresight laser
True target vectorSensor FOV
7.62 = 20mCal .50 = 60m
20mm = 100m
MEA can destroy sea mines using .50 cal or 20mm gun
•Using MEA eliminates the need to install heavy 30mm guns • No need to reconfigure the Helicopter• Real time engagement/neutralization
Advantages:-Detect -Classify-Pinpoint mines- The ALMDS -DESTROY (REAL TIME) with the MEA
7,62N = 20mCal .50 = 60m 20mm = 100m under water
Littoral Combat Ship (LCS) can destroying Mines Using the MEA
Guns.50 cal machine gun 20mm Phalanx
No gun modification required!!!
Low Angle of Entry!!
MEA 12.7x99 12.7 APSX
Bullet type APSXBullet weight (g) 60Core weight (g) 53Core diameter (mm) 12.6Muzzle velocity (m/sec) 780Recoil Momentum (kgxs) 6.7
SHOOTING IN THE AIR
X (range in m)V (velocity in
m/sec)E (energy in Joule)
500 651 112301000 524 72701500 402 42802000 326 2820
SHOOTING FROM THE AIR INTO THE WATER (RANGE 10M)
X (range in m)V (velocity in
m/sec)E (energy in Joule)
10 627 1042020 510 689030 415 456040 338 303050 275 200060 223 1320
• Samples available• In production now• Discarding sabot
SPECIFICATIONS
Target Effectiveness
DESCRIPTION RANGEMax supersonic range in air >6300 feet
Max effective range in water 200 feet
Will penetrate >12 mm steel at 100 feet u/w
Proven against torpedo at 75 feet u/w
12.7 APSX
More capabilities with the 20mm MEA Rounds
Type – R 20mm MEA• Type R (MEA): air discarding sabot and spin-stabilized core• Key Factors are:
– Excellent underwater range and performance– Stable flight in air out of the muzzle– Enters the water without ricocheting at low angles through multiple air/water
interfaces (i.e. passing through waves)– Excellent armor piercing capability, even at low angles– Sub-caliber, but larger diameter or projectile than MK258, enables internal
fuse, bursting charge or tracer, if required– Compatible with standard weapons– Compromise ‘best of both worlds’ option – air/water/low water angle/
enhance performance– Greater specific impact energy at any given range underwater
Calculated characteristics of 20…30-mm ammunition with “Type R” underwater rounds
Ammunition 20x102 20x128 25x137 25x184 30x173
Ammunition length, mm 168 203 223 288 290
Projectile weight, gram 97 110 172 222 250
Core weight, gram 72 82 130 180 190
Core diameter, mm 12.7 12.7 15.6 17.6 18.0
Core area, cm2 1.26 1.26 1.91 2.43 2.54
Muzzle velocity, m/sec 1160 1300 1120 1180 1340
Recoil momentum, kg x s 16.8 22.4 31.8 44.6 59.7
Shooting from the air into the water at range 100m
Velocity “V” (m/sec)and energy
“E” (k Joule) at underwater
range “X” (m)
X V E V E V E V E V E
30 700 17.6 902 33.4 781 39.6 831 62.2 984 92.0
60 423 6.4 625 16.0 545 19.3 585 30.8 722 49.5
90 256 2.6 433 7.7 380 9.4 412 15.3 530 26.7
120 155 0.9 300 3.7 265 4.6 290 7.5 389 14.4
150 - - 209 1.8 185 2.2 204 3.7 286 7.8
Type – F 20mm MEA• Type F: air discarding sabot and fin stabilized core
– Can provide a solution that builds upon the investment made in RAMICS by offering an incremental improvement in overall system performance. This involves replacing the supercavitating core in the current MK258 round with a compatible fin-stabilized projectile designed to use MEA’s cavitating core patent
• Key Factors are:– Penetrator diameter remains unchanged (9mm)– Weapon interface with ammunition remains fundamentally unchanged– Projectile is still fin-stabilized– Design still uses a discarding sabot– No weapon modification is necessary– Kinetic Energy at range underwater is 6 times greater than with current
MK258 supercavitating projectile
Calculated characteristics of 20…30-mm ammunition with “Type F” underwater rounds
Ammunition 20x102 20x128 25x137 25x184 30x173
Ammunition length, mm 168 203 223 288 290
Projectile weight, gram 110 120 170 190 230
Core weight, gram 85 95 130 150 170
Core diameter, mm 9.0 9.0 9.0 9.0 9.0
Core area, cm2 0.64 0.64 0.64 0.64 0.64
Muzzle velocity, m/sec 1080 1240 1130 1270 1390
Recoil momentum, kg x s 17.2 22.8 31.8 43.9 59.1
Shooting from the air into the water at range 100m
Velocity “V” (m/sec)and energy
“E” (k Joule) at underwater
range “X” (m)
X V E V E V E V E V E
30 705 21.1 876 36.4 897 52.3 1039 81.0 1165 115
60 461 9.0 618 18.1 712 32.9 850 54.2 976 80.9
90 301 3.9 437 9.0 565 20.7 695 36.2 817 56.7
120 197 1.6 308 4.5 449 13.1 568 24.2 685 39.9
150 129 0.7 218 2.3 356 8.2 465 16.2 574 28.0
Type-U 20mm MEA• Type U: water-discarding sabot
– During flight through air, projectile is stabilized by the sabot, which operates as the tail fin. Most suitable for underwater targets
• Key Factors are:– Optimum underwater range and specific impact energy (30
times impact energy/m2 compared to current MK258)– Smooth bore or rifled weapons can be used– Weapon does not require modification– Low angle of water entry enables deployment from
ships/boats/aircraft
Calculated characteristics of 20…30-mm ammunition with “Type U” underwater rounds
Ammunition 20x102 20x128 25x137 25x184 30x173
Ammunition length, mm 168 203 223 288 290
Projectile weight, gram 105 115 165 220 250
Core weight, gram 82 90 125 180 200
Core diameter, mm 12.7 12.7 14.5 16.0 16.5
Core area, cm2 1.26 1.26 1.65 2.0 2.13
Muzzle velocity, m/sec 1110 1270 1150 1190 1340
Recoil momentum, kg x s 17.2 22.6 31.5 44.6 59.7
Shooting from the air into the water at range 100m
Velocity “V” (m/sec)and energy
“E” (k Joule) at underwater
range “X” (m)
X V E V E V E V E V E
30 770 24.3 940 39.8 883 48.7 991 88.4 1163 169
60 534 11.7 697 21.9 678 28.7 825 61.2 992 123
90 370 5.6 516 12.0 521 17.0 687 42.5 854 91.2
120 257 2.7 383 6.8 400 10.0 572 29.4 735 67.5
150 178 1.3 283 3.6 307 5.9 476 20.4 633 50.1
Additional Supercavitation Benefits
• Enhanced Effect of the ‘Super’ Cavity– Near misses are still effective
• Destructive effect of collapsing cavity even with 300mm near misses
– Cavity persists in water (more than 30 metres for 30mm)• Increases chances of destroying target
More Capabilities with MEAWithout MEA• 30 mm cannon required• Heavy weapon• Excessive recoil• 9mm penetrator• Fins required• High angle ( >60 deg) needed• Must be helicopter fired• Multiple passes required for detect to engagement sequence
With MEA• 12.7 / 20 / 25 / 27 / 30 mm MEA• Lighter-weight weapon• Acceptable recoil• 12.7 mm and larger• With or w/o fins• Very low angles ( >2 deg)• Ship, land, or air platform
MEA can neutralize naval mines from high or low angles
Comparison of “W” parameters for 30mm ammunition
Ammunition 30x173
Projectile type R U F RAMICS
Parameter “W” at
underwater range “X”
X W
m k Joule x cm2
30 233 360 73.6 50.1
60 125 262 51.8 25.6
90 67.8 194 36.3 13.0
120 36.6 144 25.5 6.6
150 19.8 106 17.9 3.4
Parameter of effect upon target & explosive: W = E x S (k Joule x cm2)
At 150metres underwater range, MEA types have up to 31 x greater Kinetic Energy Area compared to MK258 projectile – from same weapon
E – energy of collision between core (bullet) and target
S – area of contact between core (bullet) and target
Conclusions• RAMICS program limited due to 30mm rounds (darts) fired from a
helicopter – not usable from ships• The 12.7mm APSX MEA is a perfect solution!
– Currently in production within the USA– Can accomplish the mine countermeasures mission with .50 caliber
weapons already installed– Can be fired from a helicopter or from a ship due to its low entry
angle capability• The ALMDS is integrated into the MH-60S helicopter to provide a rapid
wide area reconnaissance and assessment of mine threats in mainly confined straits or choke points. Just by installing a .50 cal into the MH-60S, pilots can destroy mines with the MEA immediately after detecting them. No need to reconfigure the MH 60S with the Archerfish.– Only needs an ammo change and no gun modification– Provides a cost effective solution (Less than $10k/Mines)– The 12.7mm APSX MEA is available NOW!
Reference Points• NATO Industrial Advisory Group (NIAG)
Study 159 ‘Hardkill Torpedo Countermeasures’ recommended MEA supercavitating gunfire as the best complementary hardkill solution to Anti-Torpedo Torpedo for ship defense (June 2012)
• A European navy has successfully trialed MEA 12.7 APSX against torpedo with ‘fatal damage’ to real (static) torpedo, fired from air to water with single shots, through 25 metres of water at 15 degrees angle of incidence. (Scaled trial: actual application will use Medium Calibre)
• DSGT has proven MEA effectiveness against a real torpedo at 125 metres underwater range, using 30mm MEA, penetrating at very low angles
MEA independently evaluated by NATO Industrial Advisory Group (NIAG) study as most effective
hardkill solution for ship defence