PERFORATED FUSELAGE ARMOR (PFA) CONCEPT 1 WILLIAM A. GOOCH AND MATTHEW BURKINS U.S. ARMY RESEARCH LABORATORY WEAPONS AND MATERIALS RESEARCH DIRECTORATE ABERDEEN PROVING GROUND, MD 21005-5066 National Specialist Meeting on Rotocraft Structures and Survivability Williamsburg, VA 25-27 October 2005 THIS PRESENTATION IS UNCLASSIFIED/PUBLIC DOMAIN 1
ARMOR CONCEPT PERFORATED FUSELAGE ARMOR ARMY RESEARCH LABORATORY (ARL) DEVELOPED AN ARMOR CONCEPT FOR ROTORCRAFT SYSTEMS BASED ON A WELL-ESTABLISHED LIGHT VEHICLE ARMOR TECHOLOGY CALLED P900 TIPPING PLATE ARMOR ARL DESIGNATED THE BREAKUP MECHANISM AS PERFORATED FUSELAGE ARMOR (PFA) AND COMPLETE SUPPRESION OF THREAT REQUIRES A BACKING ARMOR TO CATCH FRAGMENTS TIPPING PLATE ARMORS HAVE BEEN APPLIED TO MANY GROUND BASED VEHICLES AS AN EFFECTIVE SPACED ARMOR SYSTEM AGAINST STEEL OR TUNGSTEN CARBIDE PROJECTILES UP TO 14.5-mm PUNCHED OR DRILLED WROUGHT PLATE P900 IS PUBLIC DOMAIN WITH SOME HOLE DESIGNS PATENTED AND ARL HOLDS A GOVERNMENT PATENT ON CAST P900 ARL CONDUCTED AN INITIAL AND LIMITED PARAMETRIC BALLISTIC EXAMINATION OF THE CONCEPT AGAINST THE 12.7-mm B32 ARMOR-PIERCING PROJECTILE AT 2000 fps (609 m/s)
SPACED ARMOR DESIGNS TIPPING PLATE ARMORS - P900
SPACED ARMOR DESIGNS TIPPING PLATE ARMORS - P900
FLASH X-RAY S OF 14.5-mm AP IMPACTING P900 ARMOR
P900 DESIGN IMPLEMENTED ON M113A3 ARMORED PERSONNEL CARRIER
P900 DESIGN IMPLEMENTED ON BUSTLE OF BRADLEY M2A2 INFANTRY FIGHTING VEHICLE
ARL PATENT OF P900 WITH SKIN U.S. Patent Number 5,007,326, Cast Single Plate P900 Armor, William A. Gooch Jr., Matthew Burkins, David Weeks, Anthony Ricciazzi, Leo Mills and James Ogilvy, April 16, 1991.
PARAMETRIC TEST ARRAY FOUR THICKNESSES OF PFA WERE TESTED: 6.35-mm (0.250”) - AREAL DENSITY: 25.1 kg/m2 (5.14 psf) 7.94-mm (0.313”) - AREAL DENSITY: 31.0 kg/m2 (6.35 psf) 9.53-mm (0.375”) - AREAL DENSITY: 37.3 kg/m2 (7.64 psf) 12.7-mm (0.500”) - AREAL DENSITY: 49.8 kg/m2 (10.20 psf) 12.7-mm B32 ARMOR-PIERCING PROJECTILE IMPACT VELOCITY - 2000 fps (609 m/s) TWO FLASH X-RAYS AT 200S AND 400S COLLECTED MASS OF LARGEST FRAGMENTS IN WITNESS MEASURED VELOCITYOF THESE FRAGMENTS LETHALITY OF RESIDUAL FRAGMENTS CAN BE DETERMINED
B32 FAMILY OFARMOR PIERCING FAMILY OF PROJECTILES
PFA HOLE DESIGN
PFA TEST SETUP TWO FLASH X-RAYS AT 200S AND 400S
BEHIND ARMOR X-RAY 6.35-mm (0.250”) PFA JACKET/0.7g/477m/s PFA FRAGMENTS TAIL & JACKET/35.8g/548m/s FLASH 2 FLASH 1 PFA
BEHIND ARMOR X-RAY 7.94-mm (0.3125”) PFA MID/6.2g/590m/s JACKET PFA FRAGMENTS BULLET &JACKET/20.9g/534m/s FLASH 2 FLASH 1 PFA
BEHIND ARMOR X-RAY 9.53-mm (0.375) PFA JACKET/1.7g/606m/s TIP/2.5g/702ms MID/6.7g/598m/s PFA FRAGMENTS TAIL/11.7g/598m/s FLASH 2 FLASH 1 PFA
BEHIND ARMOR X-RAY 12.7-mm (0.500”) PFA JACKET/4.5g/454m/s PFA FRAGMENTS ?/3.0g/561m/s TAIL/10.4g/489m/s ?/6.3g/512m/s FLASH 2 FLASH 1 PFA
CONCLUSIONS ON PFA ARMOR PERFORATED FUSELAGE ARMOR OFFERS SIGNIFICANT REDUCTIONS IN THE VULNERABILITY OF AIRCRAFT TO STEEL CORED PROJECTILES BETWEEN 7.62-14.5-mm CALIBER 7.94-mm (0.313”) PFA PLATE AT AREAL DENSITY OF 31.0 kg/m2 (6.35 psf) PROVIDED LOWEST WEIGHT BREAKUP OF PROJECTILE PROJECTILE IS FRACTURED INTO SMALLER MASSES, DISPERSED AND THE BROKEN-UP FRAGMENTS CAN BE ABSORBED BY COMPONENTS OR STRUCTURE WHICH WOULD BE TOTALLY PENETRATED BY AN INTACT PROJECTILE REDUNDENCY OF AIRCRAFT SYSTEM COMPONENTS ALLOWS FRAGMENT IMPACT, BUT STILL RETAINS AIRCRAFT FUNCTION FRAGMENT DEPTH OF PENETRATION INTO PLYWOOD WITNESS WAS NO MORE THAN 115-mm PROTECTION OF CREW AREA MAY ONLY REQUIRE FRAGMENT PROTECTION (KEVLAR SPALL LINER) PFA CAN BE INCORPORATED INTO FUSELAGE SKIN