II

This document has been approvedS ,•{ for public release and sale;

its distribution is unlimited. AD

TECHNICAL REPORTS69-43-CE

I

BODY ARMOR FOR AIRCREEi4N

by

Edward R. BarronAnthony L. Alesi and Alice F. Park

January 1969

Project Reference: 1F164204D154 Series: C&ED-50

Clothing and Firr.oral Life Support Equipment LaboratoryU. S. ARMY NATICK LABORATORIESNatick, Massachusetts 01760

I'/

- - -- --

[

Grateful acknowledgement is made to Mr. George R. Ruggers andMr. Joseph E. Guilberz, specialists in fiberglass at the U. S. ArmyPicatinny Arsenal, Dover, N. J. for their contributions to thedevelo-ment of monolithic ceramic composite armor; to Mr. FrancisMccourt, U. S. Army Aviation Material Laboratory, Ft. Mistis, Virginiafor practical application of the tipping plate armor concept; toMr. George Stewart, Edgewood Arsenal, for his work in testing armormaterials; and to personnel of the U. S. Army Materials and MechanicsResearch Center, Watertown, Mass.

Appreciation is expressed to Goodyear Aerospace Corporation,Akron, Ohio, for its pioneering efforts in developing ceramiccomposite armor; to Mr. Ray Paricio and Mr. Wilbur Herbert, of Coors.Porcelain Company, Golden, Colorado, for their assistance in theproduction of the first monolithic composite; and to the NortonCompany, Worcester, Mass., for the development of Boron Carbide armor.

Recognition is also due to NLABS personnel for their contribu-tions: Mr. Robert White, physical anthropoloRistf and Mr. RichardBurse, engineering psychologist, in the supply of anthropometricdata; and Mr. Michael P. Carlucci and Mr. Peter James, clothingdesigners, in the fabrication of armor carrier prototypes., Thiswork was performed under Project No. IF16420D154i "Development of

Aircrew and Aircraft Armor Protection."

ii-

. 4'

N 1271

PI i

CONTENTS

LIST OFFIGURES , , . , , . . . o . . , , . , , ...... v

ABSTRACT & . , , . , , . . , . . , , , ... . , . , vi

INTRODUCTION , o e , 9 o e e e a o . .

ARMOR PRIOR TO THE CERAMIC COMPOSITE . .... . . . . . . 1

ARMOROF NEW COMPOSITE . . . . • . o • • 3

Curved Torso Amor and Carrier . . . ......... o • 5

Leg Armor . . . . . . . . . o...... * .... . 11]

CARACTERISTICS OF CERAMIC Co E .. ... ....... . . .o 13

C U R R D E V E L O P M E N T P R O G R A M . . . * , o . . . . . . . . . . 1

Increase inProtect ion................... 18

Design and Comfort Improvement . .. . ..........o 20

Compatibility of Armor and Aircraft . . . . . . o o . . . . 20

REFERENCES . . . .. . . . .. . . . . . . . . . . .. 21

iv

-S.

I.IST OF FIGURES

PEMS

1 Army Flyer's Flak Vest. 11952 Fragmentation Vest . . . . . . . 2

2 TRECOM Chest Protector Made of .Ceramic/Reinforced Plastic 4 . . 4

3 Experimental Small Arms Protective Vest Developed by LASin 1962 for Air Force PilotsI: 4 Pilot's Torso Sh•ield • .••:7

5 Adaptation of Flat Chest Protectors in Vietnam during 1965AMC Team Visit ..... Qoe.. 0..000 . .. . . 9 I

6 Small Arms Protective Torso Armor Carrier. . 0.. . . 10

7 Small Arms Protective Leg Armor........ .... . . . 12

8 Component of Armor Composite . . . . . . .. . 14

9 Reinforced Plastic Shell to which Ceramic Facing IsAdhered for Torso Armor Composite . . . . .. ... 1.. 14

2. 10 Front View of Composite Torso Fronts (Monolithic Ceramic)

Removed from Fabric Carriers, Showing Bullet Damage . . . . . . 16

U1 Back View of Composite Torso Fronts, Showing Bullet Damage . . 16

12 Aircrew Body Armor Vest Developed by NLABS for Air ForceUC-123 Crews . . . . 0 . 0 0 . . . 0 19

v

I •

I -

ABSTRACT

Body armor which protecta Army aircrews of low-flying aircraftagainst 7.62 mm/caliber .30 A? small arms ground fire has beendeveloped by the U. S. Army Natick Laboratories. The armor utilizesa relatively lightweight composite of ceramic b Lnded to fiberglass.Improvements were achieved on earlier ceramic cimposite armor madeof flat, multiple ceramic tiles by developing separate front andback one-piece composite panels which are curved to fit the torso.A cloth carrier with large front and back .ockets was designed tohold the armor panels, permitting the airman to wear the armorcomfortably and without interference with his operations. Experi-mental armor lor leg protection against small arms weapons has alsobeen made of this ceramic composite.

vi

INTRODUCTION

Body armor capable of protecting aircreinen against small arms ground

fire first became possible in 1962 when a new material was introduced by

4k American industry, The materi,--l, a composite of ceramic backed bymultilayer impregnated glass cloth plastic., was effective against caliber.30 AP ammunition. It was light enough so that a protective shield ofthe material could be worn without excessive discomfort.

The new armor material fortunately appeared just as the need forsmall arms protection of U. S. aircrewmen was becoming critical in SouthVietnam. The helicopter added a new dimension to air mobility as it wasused to move troops., artillery and refugees; to support U. S. groundassault operations; to evacuate the wounded; and even to recover downedaircraft. The low-level flights of helicopters, howver., brought pilotsand crewmen within the range of wall arms ground fire. Some of thefirst American casualties in Vietnam were Army aircrewmen flying recon-naissance helicopters when U. S. personnel were serving as noncombatantadvisors. The problem of small arms ground fire increased as more menand helicopters were used and as the weapons and accuracy of the enemyimproved.

U•,,-%r Prior to the Ceramic Composite

The only body armor items available to the first Army aircrewmenin Vietnam were the World War II Army flyer's flak vest and groinarmor and the standard Army M1952 fragmentation protective vest(Figure 1).

The flyer's vests were developed by the Army Ordnance Departmentduring World War II when flights generally were &hbove the range ofsmall arms ground fire and the maj rity of casualties among airmen werecaused by flak, or shell fragments 1). The vests were composed ofoverlapping manganese steel plates insert-d into a cloth carrier andweighed approximateLy 1,7 pounds, 6 ounces( 2 '. The later H1952 vest,developed during the Korean War, was fabricated of 12 pliesgj1 light-weight ballistic nylon and weighed aporoximately 8.5 pounds

Frequently, pilots in Vietnam laid two of the armor flak vests inthe nose bubble of the aircraft and the crew chiefs and gunners sat onextra armor vests .). These p. :autions were unsatisfactory, however,since the armor flak vests were not adequate against the greater pene-trating power of small arms projectiles.

The first attempt to protect pilots specifically against thesmall arms threat cane in 1962 after an Army ballistic-protection survey

Ii•

rryFyrs lkVs

[15 rgenai.Vs

Fiur

-2U

I

team visited Vietnam(5). The team, headed by the Army TransportationResearch and Engineering Command (TRECOM), evaluated various ballisticthreats to aircraft, combat troops and vehicles.

As a result of this study, TRECOM designed a pilot's shield made of1-inch thick Doron, a fiberglass fabric plied and bonded together withpolyester resin. These 17.5-pound shields were designed to be held by theairman in front of his chest, with the armor resting on his thighs. Theshields were to be used with a system of thin, metal tipping plates whichwere attached to the center and rear sides of the helicopter or small air-plane. The plates were intended to decrease a projectile's penetratingpower by tipping th° bullet so it would present a larger surface areato the pilot's shiei.2.-

The shield and tipping plates were part of a kit which al5so: includedseat panels of j-inch Doron for the sides, bottom and back of the pilotand copilot seats. To meet the urgent requests for armor protection,TRECOM assembled more than 150 of these kitty6 or H-21 and UH-I helicoptersand shipped them to Vietnam by January 1963''?.

Because the weight of armor inevitably compromise, * payload, fuelor other performance aspects of a helicopter, the mili ast seek theoptimal degree of protection for th'i least weight. Th; -.,siderationrestricted the use of heavy armor materials, such as Jc_ &Ad steel,and thus the total aircraft and personnel body area which could be pro-tected. Therefore, lighter protective materials were required.

Armor of New Composite

The dev 9opment of the relatively lightweight ceramic/reinfcr;4plastic composite material during this period opened new possibiliiee forsmall arms protective armor. TRECOM became interested in the new materialthrough the U. S. Army Natick Laboratories (NLABS), which was investigatingthe potential of the composite for armor. The superior ballistic strengthof the composite would make it possible to eliminate the tipping pi tesand to provide direct protection in seat panels and chest shieldsM7 ).

Thus the first body armor made of the composite to reach Army pilcteand o.pilots in Vietnam were chest protectors supplied with the newTIECOM aircraft armor system (Figure 2). The chest protectors weredesigned like the earlier Doron shields, and were just as uncomfortableand heavy resting on the pilot's thighs. The pilots vere unable to wearthem for any length of time.

Concurrent with these developments, NLABS was exploring ways toutilize the ceramic composite in armor designed so that aircreimen could

S-3-

Ur

� I

7-

p

I - I

I -I/

I

Figur. 2. �COK Chest Prolector lade of Cera.ic/Reinfore.d P3.asti.�.

.4-

L

wear it comfortably. The first composite armor made by NLUIS was a vestdesigned early in 1962 at the request of the Air Force at Eglin AFB forpilots in Vietnam (Figure 3).

Curved composite tiles of various sizes were shaped to fit intomultiple pockets of the vest, which were made from ballistic nylon toreduce ceramic 3pall. The vest concept proved to have several dis-advantages. The seam areas between the ceramic-filled pockets werevulnerable and the heavy plates abraded the inside of the pockets.

NLABS next applied the new material to a curved torso shield(8).The shield was made of 13 curved, ceramic tiles bonded to a shell whi chextended from the wearer' s collarbone to the groin area. The weightof the snield was supported by an extension which rested on the seatbetween the pilot's legs. The shield was positioned in front of thepilot by two straps joined to the seat harness (Figure 4).

Firing tests at the Ballistic Research Laboratories (BRL), Aberdeen,Maryland, in March 1963, indicated that the torso shield would stopcaliber .30 ball and AP ammunition at 100 yards at 0 - 450 obliquity(9).There was a concern t1at a caliber .30 bullet dofeated by the armor coaldstill cause severe injury to the body by its impact. The BiophyvicsLaboratory at Edgewood Arsenal, Md., tested the composite and =oncludedthat the force of the impact from a hit would not present a seriousproblem.

The torso shield was then field tested in Vietnam by the AdvancedResearch Projects Agency (ARPA). ARPA reported thct shield was effectivo"and reasonably comfortable but tended to interfere with the pilot'soperation of aircraft controls.

Curved Torso Armor and Carrier. Up to that. time- NLABS rebabrcheffo. ts in aircrew body 4rmor were somswhat hindered by laek of fielddata on the problems of small arms protection and armor needs. InAugust 1964, the Army established a requirement for aircraft andaircrew small arm3 protective armor, Tie Army i1L-teriel Command (AMC)assigned the responsibility for development of aircrew body armor toNLABS. The development of aircraft armor was aasigned to the ArmyAviation Materiel Coiiax dAVcOM) along with TRECOM (now AviationMateriel Laboratories) 1 0•. In 0he fall of 1964 an urgent requestwas received for small arms body armor for crew chiefs and gunners-in Vietnam.

NLABS inteitrm a oeo~g experimental cu~rved torso and•:•: NLABS~~in the interim., was dovelou'rgexrintl dtos n

leg armor to be made of the composite. Action was initiated to procure

-5-

6-

I

V

I

I

I II

II II I

II

I

Figure 3. Rxperiuental �al1 Arms Protective Vest Developed by NLABS in1962 for Air Force Pilots, Incorporating Plates of CeramicComposite in L�lividua1 Pockets of Vest.

-6-

Experiuental Pilot'a Curved TorsoShield without Shield Cover,Rerealirig 13 Ceramic Till'. Llondedto Reinforced PIsWi4 Shell.

tip" 4. M~ iot'to Torso Shield

Miot'to Torso Shield with ShieldCover,, Shoulder Straps arA Support-ing Extension at Gr'oin Are&.

prototype ofW the torso and leg units ý.n quantity. The terso conceptsincluded a curved unit made of multiple composite tileB and a curvedurit of threa rigid sectionsý The units were designed to be worn inan experimental cloth carrier, T65-1 (Figure 6).

The carrier hzd large envelopes to contain a front torso piecefor the pilot and copilot, or front and back plates for thi gunners,who exposed their baoks a3 +hey moved about the aircraft. The front

and back units wei-e attached by adjtistable straps to padded shouldersections. The sides of the carrier were closed by nylon hock andmatching pile Zlaps which permitted size adjustment and quick doffing.

AMC formcd a 5-man armor team to visit a llthe Army aviationunits in South Vietnam in Fobraary-March 1965( ). The visit gave teammevbers from NITABS, AVCOM; TRECOM and BRL a cý.hance to gather field datafor further armor research.

The team discovered that none of the pilots or copilots were usingthe TRE"OM composite chest protectors as intepded, although some of'ie crelimembers were wiring the shields to troop seats to improviseartor protection. The pilots complained that the weight and position-ing of the shield on their laps caused such discomfort and restrictionthat they preferred exposure to small arms fire.

The AMC team devised a method to modify the 500 available chestprotectors so they could be worn orn the man. The units were shortenedby three inches to Ift into a fabric carrier (T65-1) designed by NLABS.Arrangements were made to modify the units and to fabricate the carriersin Vietnam to provide immediate small arms protection.

In addition, the new toi'so and leg armor models vere evaluated byapproximately 100 pilots and 80 gunners and crewchiefs.

The air creimen enthusiastically repor-ted that the new wearable torsoarmor vas t:*mfcrtable, nonrestrictive and easy to don and doff. Thecrewchibfs and gunners were especially interested in the carrier idea.Because of their mobility, these creumembers could not use loose chestprotectors or shields attached to the seat.

On the basis of this on-site evaluation, the Army Support Command,Vietnam, (USASCV) requested a quantity of the curved torso armor unitswith carriers.

A second AMC team visited Vietnam in February-April 1966, toinform Army aviation units of the latest armor developments and todete-mine if any readjustments in objectives were necessaryOll.

B3ased on the two visits to Vietnam, NLABS improved the armor carrierso that it was more comfortable to wear and easier to operate. Elastic

Flat-'- --. Ceai/ei~re Plastic

Ches Proecto of ype uppled t

Moife Chest Protecto ofTpeSplidt

T65-1 NLABS Armor Carrier.

Figure 5. Adaptation of Flat Chest Proteactors in Vietnam during1965 AME Team Visit.

-9-

a"I

-webbing replaced the non-stretch fabric at the sides, and sliding shoulder Jstraps allowed a more critical adjustment of armor height than the earlierstraps with snaps. The new carrier opened only at the right rather thanboth shoulders, so the front and back units remained joined when theairman slipped the carrier off his right shoulder (Figure 6).

The spallJ and fragnent protective qualities of the carrier alsowere increased by adding ballistic nylon felt to the shoulder paddingand to the inner lining of the plate pockets.

The armor plate itself was made with a new curved, one-piece con-struction instead of multiple ceramic tiles. The new carrier and armorwere flight tested during the second AMC team visit and were readilyapp:oved by the users.

Leg Armor. Gunners and cre-whiefs in Vietnam were also veryinterested in the NLABS leg armor which was demonstrated during the AMCteam -visits. The armor consisted of frontal thigh and lower leg unitswbich were joined at the knee by an articulating hinge (Figure 7).

The first leg armor was fabri.:ated from dual hardness steel becausethe composite made with multiple ceramic tiles did nAt lend itself tocritical shaping. Approximately 500 pairs of the steel full-leg armorwere delivered to Vietnam early in 1966. Later the development of aone-piece composite c3nstruttion, which could be shaped to conform tothe curves of limbs., made it possible to use ceramic composite ratherthan steel for leg armor.

* The new composite leg armor was flight tested during the second AMOif team visit. It was an improvcment over the steel leg armor but crewmen

* !reported the clumsiness and weight of the full-leg unit still hirneredtheir mobility. Despite these disadvantages, helicopter crews desiredthe extra protection, and more than 300 pairs cf the composite leg armorwere supplied during 1967.

NLABS has since designed a new lower leg unit of the ceramic/fiber-glass composite which weighs an average of 18 pounms a pair - 20 poundsless than the dull hardness steel full-leg armor (Figure 7). The upperthigh unit was eliminated as the major source of weight. discomfort andarticulation problems. The thigh unit required a hip harness with strapsto stabilize it when the aircrewman stood up. When the man was seated,the armor lay or. the uppcr surface of his thigh and did not pttect himfrom ground fire. The knee hinge posed adjustment problems because of"variations in the seated knee height of crewmen(12i.

The new single, lower leg unit is anatomically shaped to differen-tiate between right and left legs (Figure 7). An outward curve at the

-- _

Aicrew MmberDemonstratesFull

Thg/n/owrLgAko aeo

DulHrns Se9.Nt

Hans fo -Mah:~ Aro an

Xzprium~ta, single-piece Lw)*-rLeg Armor with OuitLd Curve at

I ~Kneea andl Differential Shapin~gFor Rih and Left lesgs.

Figure 7. 3A&ll Arms Protective Leg Armor

I I

tU

knee prevents contact between the knee and armor, and provides someprotection to groin and upper body areas. A foot bracket serves tostabilize the armor on the leg and to transfer the armor weight fromthe wearer's leg to the ground. A small quantity of the lower legunits is being procured for testing.

Characteristics of Ceramic Composite

The modern histoiy of the material which made the new body armorpossible actually dates back to 1945. That year, Commander A. P. Webstr,U,, S. Navy, conducted experiments with plate glass placed over Doron(135.The combination proved caprable of stopping caliber .30 rifle bulletswith much less weight 6han conventional steel armor.

In 1955, MNLS began applying similar composite principles to lightý-weight armor vests to protect infantrymen against munitions fragmentsJ4).Various ceramic/reinforced plastic composites were evaluated but theywere not effective at weights low enough for body armor.

A new era in small arms protective armor opened in 1962 when industrycut the weight of armor in half with a ceramic composite. This composite,using aluminum oxide ceramic for the front component and Doron for theback, was the first practical armor material capable of defeating caliber.30 AP projectiles at close range. The components of the composite arediagrammed in Figure 8.

The spall shield, wbich faces the projectile, originally was a coat-ing of polyurethane rubber. NLABS developed the present space shield ofballi 3tic nylon cemented to the ceramic to contain or reduce cersimic andbullet fragments resulting from a hit, thus minimizing the hazards tonearby personnel and equipment from flying fragments.

The next component, the ceramic facing, was fabricated from aluminumoxide for the first armor procurements. Later, industry developed addi-tional ceramics for the facing.

Most of the early back components were fabricated from Doron (a lowresin content laminate made of glass cloth with a starch finish and anunsaturated polyester-styrene resin), although a limited quantity weremade of aluminum alloy. In 1965, a different reinforced plastic (awoven-roving type) replaced Doron for the backing as a result of materialsresearch at the U. S. Army Picatinny Arsenal. The new backing materialincreased the penetration resistance of the composite and cost less thanDoron. A torso backing made of this reinforced plastic is shown inFigure 9 without the spaJl shield and ceramic face.

-13-

SPALL SHIELD COMPOSITEADHESIVE ADHESIVE

SPPLL SHIELD CERAMIC REINFORCED PLASTIC

PLASTIC -CERAMIC COMPOSITE ARMOR(EXPANDED VIEW)

UNITED STATES ARMY

Figure 83. Components of the Armor Composite are., from thele~,the Spafl Shield wahich Faces the Projectile;

th%. Spali Shielid Adhesive; the Ceramic Facing;the Composite Adhesive,, and the Reinforced PlasticBacking.

Figure 9. RIeinforced Plastic Shell4 ~to wihich Ceramic Facing

Is Adhered for TorsoArmor Composite

The weight ratio of the ceramic facing to the reinforced plasti cbacking is not particularly critical. For caliber .30 protection, thebacking is roughly one-third of the total composite weight and i-Lnchthick. The adhesive which bonds the front and back components may bea two-part, solventless polyester-polyurethane or polysulfide. Untilrecently the ceramic front was adhered to the backing after the rein-forced plastic was molded into shape. Now the two components arebonded together while the backing is being molded.

The combination of ceramic and reinforced plastic is effective at amuch lower weight than either of the materials alone, or any other singlematerial of equal weight. The composite acts on ball and armor-piercingprojectiles with a slight variation. Ball projectiles are shattered atimpact into fine particles which spew out of the crater formed in theceramic. With armor-piercing bullets, the jacket is stripped off andthe projectile is broken into pieces. In both cases the back component"stops and/or contains the projectile pieces.

The damage produced by bullets on aircrew torso armor is fairlylocalized, as can be seen in front (Figure 10) and back (Figure 11) viewsof the armor. On the fronts, the inner circle where the ceramic ha- beencompletely expulsed by the bullet is approximately one inch in d!a•ater.The outer circle of fractured but adherent ceramic is approximately4 inches in diameter. Individual cracks may extend further, dependingupon the ceramic's size and shape, and the impact location.

The reinforced plastic shell behind the shattered ceramic may be"unaffected" by the bullet, as in the area indicated by the arrow inFigure II, or the backing may be bulged or delaminated, depending on"the severity of the ballistic impact.

The ballistic efficiency and design of the composite material havebeen significantly improved since its first use. The greatest progresshas been achieved in the ceramic component. Initially, the ceramicfacing consisted of individual flat, 6-inch square tiles adhered to thereinforced plastic back. These tiles had to be made with raised edgesand carefully hand-fitted onto the shell to minimize ballisvic weaknessat the joints.

Further development by NLABS and industry led to curved ceramictiles which made it possible to shape the shields more closely to thehuman torso. The curved armor fit more comfortably and was lighterbecause of its reduced surface area.

By the summer of 1965, the ceramic was made in Aingle torso-3izej,curved plates. The technology for the monolithic ceramic was cengv-dand developed by armor specialists at NLABS and Picatinry Arsenal%

S~-15- 1"k

II

Effect of Bullets on Aircrew Armor

.3.

Figure 10. Fro.nt View of Composite Torso Frcnts (Monolithic Ceramic)Removed from Fabric Carrier. Caliber .30 AP BulletsPenetrat.ad Spall &anld, Fo-red Craters i', the CeramicFacing and fractured the Sur.,.-undiW Ceramic.

Figm-e U. Back View of Torso Fronts, 5hown in Sai Order WithoutFabri- Carriers, Reinforced Plastic Baek lng at leftWe* Not Visibly Damaged by Lower Hit Near Arrow butIThowo Bulging from Upper Hit.

I -16-

The new monolithic ceramic strengthened the composite by eliminatingthe mdultiple tiles which were ballistically weaker at the jcints than theedges by several hundred feet per second. The one-piece ceramic alsoexpanddi the possib1liti,)s of armor protection because it could be shaped

ýo follow the more complex curves of limbs and vital aircraft equipment,thereby reducing bulk and weight of the required armor.

New matarials have been used for the ceramic, in addition to aluminumoxide. to meec th'e rising prcduction demand and to r-duce the weight of theceramic component. Torso sets of boron carbide and silicon carbide, weigh-"ing one to three pounds less per set than alumina, were initially procuredin 1965. The weight of boron carbide and silicon carbide armor (with thespall shield) is 22% and 10% less, respectively, when compared to aluminumo.'ide armor.

However, the carbides are at present two to four times more expensivethan the alumina because they cost more initially and are more difficultto fabricate into aimoro The boron carbide, made at first with individualtiles, is now produced in c monolithic form simi.lar to thie alumina. Thesilicon carbide fronts must be mad; ir a two-piece construction usingleft and right halves bc-cause ofZ the mvxinrum piece width that cam be pro-duced ir, oxisting tube furnaces.

:ivestigation of other ceramic materials continues. One promisingceramic is a combination of boron carbide and silicon carbide which iseffective it, a weight between the two materials. Other potential candi.-dates being studied by industry are beryllum oxide and silicon nitride.

Th.- contributioi.s of aircrew armor to military efforts are very realbut di ý.ut to substantiate. Certainly the armor has increased theeffectis, iess of air rescue teams under evemy fire and the overall tacticalutility of air cavalry by promising some protection to aircrews and pilots.

Actual statistics c.r the number of wounds or fatalities prevented bythe armor have been difficult to collect because of the rapid medicalevacuation _f the wounrled a~x1 the pressures of combat. Casualties oftenSaro evacuated before information ')n the 7= of armor worn, the nrotectior.provw.ded by the armor, tha nature of the wiunding agent, the range of fireand othev azctors can be reported. Such information then becomes a matterof speculation.

Despit, these difficulties, the U. S. Army Vietnam (USARV) obtaineddata c-n 72 aircrew casualties occurring from July 1966 through June 1967

small but fairly representative sample since cases were reported f•,every sector .f South Vietnam and almost every type of aviation unitfM"•The data ravealed that 76.4 percent of the 72 airmen wore the torso armorand in se,',ral cases the armor clearly prevented serious injury or death.F•,zr, .the extremely low incidence of wounds to the chest and back(3.6 pP'cernt of the total) was attributed to the prot, tion of the torsoarmor and ar=red seats.

_17-

I

In contrast, the lower extremity accounted for 40 percent of woundsto the 72 canualties. Nearly half of these occurred to the lower legand knee -- a disproportionate frequency for the body area exposed. Air-crews reportedly were not using the steel or composite full leg armorbecanse of its awkwardness. The improved, experimental lower-leg armorwas not available.

Current Development Program

Increase in Protection. The rapid progress in the art of small armsprotective armor since its beginning in 1962 has enabled the Army toraise its objectives for body protection. Aircrew armor now protectsagainst direct as well as oblique hits of caliber .30 AP at 100 yards.It is hoped calibei .50 protection will be possible at a later d;,te.

In the 1967 USARV study, the projectiles which caused the maj(ri.v Iof the casualties were caliber .30 bullets or 7.62 mm mmun.tion(6).Nearly half of the cases were wounded by intact bullets. However, 30percent were wounded by fragments from shattered bullets. Suchsecondary missiles, a frequent cause of minor injuries, inay alsoinflict severe wounds because of their size and sharp, irregular edges.Airmen have lost an ey? to fragments ricocheting off the aircraft com-ponents and body armor 17). I

A current goal is to increase spa-ll and fiagment protection. To adegree such protection is provided by the ballistic nylon covering theface of the composite plates, and by the ballistic nylon felt in theshoulder padding and plate pocket linings of the carrier. This pro-tection is not adequate, however. The USARV study reported that 30.5percent of the 72 airmen studied wore an M1952 vest over or under thetorso armor. On the basis of such data, USARV recommended that fragment ]and small arms protection be combined in one vest to eliminate the dis-comfort and bulkiness of two items.

NLABS had anticipated this need early in 1967 when it designea- 3vest-like carrier for Air Force UC-123 crews engaged in low-flyingdefoliation operations in Vietnam. The vest was made of a layer ofballistic nylon felt and two plies of ballistic nylon. The fabric corn-bination not only defeats spall and shell fragments, but also eeduce-sthe ricocheting of fragments by retaining projectile splash and cer&nicspall. The high collar, also made of felt and ballistic nylon, prcvide't-a high degree of protection to the neck area. The fabric combinationextends the fragment protection of the T65-2 to the neck, upper rightand left chest areas, the lower back, sides and lower abdomenr ,Figare 12;..

For this additional protection, the experimental carrier adds5 pounds to the present body armor system - approximately 4 pornizless than the 'ra952 vest - and, as a single item, is much more co-.fort-able than the combination of torso armor and 111952 vest.

[ -18-

0?YX~

VFigure 12. iiircrew Biody Armor Vest Developed by NIABSforAier Frorctie Upla23 andw C abibers 3AP Protection.

-19-

NLABS has also used the ballistic nylon and nylon felt in anexperimental 3-pound diaper-like garment for groin and buttocks pro-tection from spall and fragments. Leg coverings of the ballisticfabrics are being considered.

Design and Comfort Improvement. The present sizes of short., regularSand long torso units are based on a tariff worked out at NLABS toSexpedite production of the first armor.

To improve the fit and comfort of body armor, a new sizing systemis being drawn up under contract l1). Because conventional sizing

systems are set up for flexible, enclosing garments, a special systemis needed for rigid armor units.

Anthropometric data gathered by hU=BS and the Air Force have be,-nanalyzed to determine the body dimensions most relevant to the properfitting of torso and leg armor. Four torso sizes (two widths for eachof tuo torso lengths) and two leg armor sizes (two length and widthcombinations) have been proposed. The new sizing system will beimplemented as production adjustments are made.

The comfort of the armor also will be improved by anatomicalshaping. Existing armor is curved with a uniform radius in horizontaland vertical directions. The contractor has developed molded torsoarmor with compound curves *qgh reflect the body contourE of the upperchest and back more closelyZxJ. The contoured armor provides increasedside and peripheral protection. New lower leg armor also incorporatesthe anatomical shaping.

"":tibility of Armor and Aircraft. As new body armor is

developed, it must be coordinated with aircraft armor and aircraftdesigns. In May 1967, the U. S. Army Human Engineering Laboratories,Aberdeen, Md.., began a study of the interior design and work performancerequirements of all Army aircraft from the present through ai-rcraftplanned for 1975. The study will guide NLABS technologists in develop-ing body armor -which does not hinder the airman in his flight duties.The aircraf't and body armor systems will be coordinated for eachaircraft to minimize the weight penalty.

Another aspect of the compat~ibility problem is the performance ofbody armor in the event of an aircraft crash. The body armor must notinterfere with the escape fetures of the particular aircraft, such asejection seats, door exits and parachutes. Little is known about theeffects of body aimor on the airean if he cannot doff it before crash-ing. In May 1967., a contract was awarded for testing the crashworthinessof existing and experimental- body armor items.

-20

S,,.~,'.> --. ' .7-7---7

AI

.1

REFERENCES

1. Palmer, Allan, M.D., "Survey of Battle Casualties, Eighth AirForce, June and August 194," Chapter IX, Wound Ballistics, Army MedicalDept., Office of Surgeon General, Dept. of the Army, Washington, D.C.,1962, p. 557.

2. Beyer, James C., Major, MC; Enos, William F., M.D., andHolmes, Robert H., Colonel, MC, "Personnel Protective Armor" Chapter XI,Wound Ballistics. Army Medical Dept., Office of Surgeon General, Dept.of the Army, Washington, D.C., 1962, pp. 666-667.

3. Study of Flight Armor Requirements and Developmental Approaches,Chemicals & Plastics Division and Textile, Clothing & Footwear Division,Quartermaster Research & Engineering Command, July 1957.

4. Repcrt of Vis3it to South Vietnam, Aircraft and Aircrew ArmorTeam, AMC, 10 February - 21 March 1965.

5. Ballistic-Protection Survey Team's Activities Report 1 August -

20 September 1962, Vietnam, Office of the acretary of Defense, AdvancedResearch Projects Agency.

6. Briefing on Aircrew Armor Protection, 31 January 1963, atUSAF Hdqt Tactical Air Command, Langley Field, Va., Memorandum for

Record, AVM-CCE, 5 February 1963.

7. Report of Travel to Eglin AFB, Florida, by Edward R. Barron,. 16 October 1962, C&FD Branch, U. S. Army Natick Laboratories, Natick,

Mass.

8. Patent Disclosure, Pilot's Torso Lifeshield, Kennedy, S. J. Dr.,Barron, Edward R., Holly, lI-ldred K., and Buffington, Dale W., Major,1963.

9. Report of Travel to Ballistic Research Laboratory, Aberdeen,Md., to Conduct Ballistic Test of Ceramic/Fiberglass Pilot's TorsoShields, T63-1, 14 March 1963, by Edward R. Barron, C&FD Branch, U. S.Army Natick Laboratories, Natick, Mass.

1 0. Letter, AMCRD-SR, 18 September 1964, Subject: Dept. of the Army

Approved Qualitative Materiel Requirement for 4ircraft Crewmen ProtectiveArmor Equipment.

11. Report of Visit to South Vietnam, Aircraft and Aircrew ArmorTeam, AMC, 14 February - 4 April 1966.

-21-

A-.

12. Rodzen, R. A., Scribano, R. C., and Burns, M., Development ofSizing Criteria for Aircrew Armor Systems, Phase II, IIT Research Institute,Chicago, Illinois for U. S. Army Natick Laboratories, 31 May 1967.

13. Webster, A. P., "Diphasic Armor 1. Glass Doron; Status Report,"Research Division, Bureau of Medicine and Surgery, Navy Department,July 1948.

14. Alesi, A. L., Composite Personnel Armor Technical Report CP-5,U. S, Army Natick Laboratories, December 1957.

15. Barron, E. R., Disclosure of Invention for Monolithic Armor,April 17, 1967.

16. Bezreh, Anthony A., Major MC FS, Interim Report on InjuriesResulting From Hostile Action Against Arm= Aixcrewmembers in Flight-United States Army Vietnam, July 22, 1967.

17. "Aircrew Protective Armor," Letter to Commanding General, U. S.Army Natick Laboratories, from Colonel William G. Sullivan, Commander,Army Concept Team in Vietnam, March 1, 1967.

18. Rodzen, R., Lamber, C., Scribano, F., Burns, M. and Singer,Ronald, Dr., Research and Development of Aircrew Armor Systems, IIT ResearchInstitute and Barron, Edward R. of U. S. Army Natick Laboratories,January 1967.

19. Final Report - Body Armor, Army Concept Team in Vietnam, Dept.of the Army, June 12, 1967.

7!

-I

1 ~-22-.

I!

rI

UnelassifiedSecullty ClossIfication "_

DOCUMENT CON'I 40L DATA:

(Security elaili... etion of title. body ol abstract and indexingincj lation must be etered whe, the ove•all r*"" i. ciaelfled) -

1. ORIGIIATING ACTIVITY (Co•porate author) 341. REPORT SECURITY CI-ASSIPICATION

Us 3. Army Natick Laboratories U1nolassifiedNatick#. asahueetts 01760 Ab. GROUP

3. REPORT TITLE

BOOT AMICR FOR AIRCRPM

4. O9SCRI IVK NOTES (2ype o* report and incluseiv detse,

s ,nzy h ,eert, A9 ,967 9S. AUTHORIS) (Fitr? nWW. middle fatalll, leat &me)

dlirwwd i. Barren Anthwn L. Alesi and Alice . Park

O- REPORTZATZ 74. TOTAL NO. OW PAESý 1 7b. 140. ma rEPs -

Jamaff 1969 22 19S8. CONTRACT OR GRANT NO. to. ORIGINATORS REPORT NUJUER|(S)

b. PROJECT No. lFlM2"gD154 69.43-c, Cis-50

C. 9b. OTHER REPORT NO(S) (Aaoer asm•uers tat S in be aseireod

10. DISTRIBUTION STATEMENT

This doemeut has beu approved for public releae and sole; its 4d!statibutionS28~1 Ual~ll:Ltod.I

£t II. SUPPLEM4ENTARY NOTIKS i1. SPONSORING MILITARY ACTIVITY

Uo 3. AM Natick Laboratorleslatick, N]ass 01760

IS. ABSTRACT

Body armor il*ich protects AM aireroe of low-flring aiparaft against7.62 wo/ealiber .30 AP smaU ar grpoun fire has been developed by theUo 3. Anr Natick Laboratories. The armr utilises a relatively ligbtweigkteimpesito of ceramic beaded to flberglasso The U. S. Anry Natick Laboratories, proved on earlier ceramic empesite armr made of flat, multiple eer-eae curved to fit the torso. A cloth carrier with larg. front and back pookets

was desiged to hold the armor panals, permitting the airwi to war thearmor comfortably and without interferonse with his operations. imentarmor for leg protection apaint emall am* weapons has also been made of theSeraie composaite.

ro pO.47 RPLACUS Do FORM 1472. ' JAN4 WHICH ISD I Nov Sol 4 O7SOL-T, FOR ARMY USE.

Iewfty ~1astflagia.u

1 4. LINK A LINK 0 LIN C

Aviatiam peroamn1

*MAU AiMs* At1n em) iii 94

34y~t 109

Flbuwgla 109Curits 10

I Ueecwft Classification