is. 00

U«xc*l Regcarch Reference: 6065 Ao^ust 26, 19CU

Pic«tinny Arsenal Dor«r, I. Y,

Atta: Procurewnt and Product ion Directorate SMUPA - PBI

HARD COPY

MICROFICHE

Subject: Contract lo. DA-0A-20O-AMC-A77 (A) Developnent and Bhraluatioo of a Lightvelght Alu»inum Honeycomb Caae

Ik- Ji Monthly Progress Baport #7

QmtltWMt

Enclosed is the report describing the work done on the subject contract

daring the aonth of July 196k. The report v«s prepared by the Advanced Struc-

tures Group, Research Division, Hexoel Products, Inc., Berkeley 10, California«

Included as attachaen .« are (1) Statement of Man Hours Expended - July

1961*, (2) Schedule shoving Current Progress - July 196kt and (3) Schedule

shoving Prograa of Ensuing Activities - August and September I96H.

Yours very truly.

ECVtJee Attachaents (3)

l, C, Vicars Research Director

DDC

JAN i ö IdbD

ÜlbU U bill DDCIRA B

-1-

Hexcel Research CONTRACT NO. DA-OH-^QO-AMC-l*77(A) Reference: 6065

REPORT OF PROORESS JULY 196i*

1. TRGTINC OF CA3B HXJi-5477

1.1 Vibration Taste

The aet-up for the testa vaa the siuae aft that used during

the Tlbration testing on Case HXL-U-i*77 vtth the follovlng ex-

ceptions. Aceeleroaeters #2 and 0h were mored fron the internal

pay load veb (subject to oil canning) to the edge of the more

rigid plate which is attached to the front end of the adapter

ring. The tie rods on the fixture used to support the Case for

the vibracion along the longitudinal axis were changed from

606I-T6 aluBlmuD to cold rolled steel.

The Case was placed with the longitudinal axis in a horizontal

position and tested by vibrating it along the vertical axis. The

Case was then placed with the longitudinal axis in a vertical

position and vibrated along the longitudinal axis. Peak accelera-

tion values are sunarised in Table 1. No daaage occurred to the

Case during either test.

1.2 Svaluatioo of Vibration Test Results

A coaparison of the peak accelerations occurring during the

testing on Cases \lJL~h-hj'J and HXL-5-^77 is shown in Table 1.

All of the significant peaks on both Cases were recorded either

on Acceleroaeter 12 or fit. Therefore, values recorded fro« the

other aceeleroaeters wejat not listed in Table 1. The differences

-2-

Haxc«! Research COITRACT JIO. DA-oW00-AMC-J»7T(A) Rafarence: 6065

in tha aeealaratlon Bagnltudes for paaks which occurred at siallar

frequanclet on tha two Casas «ara apparently tha result of Boring

AccalaroMtera #2 and #** fro« tha internal payload vab to the

plate attached to the front end of the adapter ring, Vor all hut

tvo peaks, the acceleration aagnitudes were lover for Case HXL-5-^77

than for Case HXL-J»-^TT. This indicates that then vas less magni-

fication on the adapter ring plate than on the internal vab.

2. DBSIGW OF CASS HIL-6-^77

Mo drop tests were performed on Case HXL-^^TT so there vas no basis

for aodifying the core design on Case HXL-6-U77, The primary change vas

in the use of Mylar for the skin of the energy absorption cylinder and

Butyrate Cellulose Acetate for the skin of the front and rear energy ab-

sorption end caps. A diagram of the Case la shovn in Fl(Pfure 1. The

dimensions of the core cutouts are the same as those on Case HXL-5-U77

vhich are shovn lr Figure k of Progress Report #6.

3. TT-^THQ OF CASE HXL-6-477

3.1 Hydrostatic Preasure Test - 3 psl

A diagram of Case HXL-6-J477 is shown in Figure 1. The bond

between the plaatic faces and the energy absorption core of the

and caps vas very poor in that large areas remained unbonded

after fabrication.

A prototype locking device was used in the front end cap in

place of the aluminum seal plate which vas used in previous

-3-

H«c«l ÜOMarch OOHTRACT MO. DA-(A-200-AMC-^T7(A) R9fer»ne« t 6065

prtvsor« tests. Th« locking derlcs VM f%st«D«d to the head of

ths toamj psjrload by a msehiiM scrsv. Details are shown ID

Figure 2.

Strips of blotter paper were placed Inside of the hydrostatic

eyllnder to senre as a eethod of detecting water leakage. One

piece was placed on the inside of the reeorable front end cap around

the opening for the locking derice. A second piece was placed on -

the inside of the rear end cap« Two additional pieces were placed

around tbm circtvference of the inside of the cylindert one Ineedl-

ately above the adapter ring and one lanediately below It.

The gage pressure was cycled fro« lero to 5 pel twice. The

pressure was held at 5 psl for 5 minutes at the end of each cycle.

Ho noticeable pressure drop occurred at any tine during the test.

During the test, the front and rear end caps becaae partially m

filled with water. The energy absorption core filled with water

to a lewel of frost 7 to U inches free the rear end of the energy

absorption cylinder (excluding the rear end cap).

After the speeiaen was reaored fron the pressure tank, the

front end cap was reaored. There was approximately one inch of

water at the botton of the hydrostatic cylinder. All blotter paper

used in the cylinder wan dsap.

The edges of the front end cap buckled inward lA" to 3/6" all

around the eircunference. The core was crushed Inward (and pulled

away fro« the skin) approxinetely one Inch at two points on the

-4-

H«xc«l Research CORTHACT HO. DA-OH-200-AMC-l»77( A) B»ference: 6065

circuaference. There ma very little peraanent deforvation in the

skin of the rear end c*p or the cylinder other than a alight vaviaesa.

3.2 BTaluatlon of Hydroetatlc Pressure JIU& Raaolta

Part of the water In the hydrostatic cylinder probably entered

the cylinder vhile the front end cap was being removed. There was

no vay to tell what proportion of the water cane fro« this source.

Tbc reayainier of the water could have leaked in (1) through the

Joint between the hydrostatic cylinder and rear hydrostatic end cap,

(2) throogh the Joint where the threaded I-sectlon is bonded into

the hydrostatic cylinder, (3) past the O-ring at the front end cap,

(1») past the seal ring between the locking device and the front hydro-

static end plate, (3) past the bolt and washer which attach the locking

device to the dtusqr pay load f or (6) through the longitudinal seaa in

the wall of the hydrostatic cylinder.

It was concluded that the priaary source of the leakage into the

hydrostatic cylinder occurred by way of the locking device seal ring.

k. DgaiCB Of CAaJt aiL-7^77

This Case is basically the saas as Case HIlr-^-^YY. Aluainu« skin was

used throughout. The circusiferentlal cutouts in the energy absorption core

extend coepletely through the core as with Case HXL-^??, and the core

cutout diesnsions are the saas as those on Case HXL-5-1»77. A diagran of

the Case is shown in Figure 3.

-5-

Hexc«! Research CONTRACT SO. DA-0'4-2OO-AMC-^7Y( A) Reference: 6065

The priB&ry design differences between rases HXL-5-^77 *nfi

UXL-T-1*?? are susaarired below.

H,1 The skin gage was changed from .012 to .00^3 In the following

places: inner and outer faces and edgeR of front energy ab-

sorption cap; outer face of rear energy absorption cap,

inner edge of rear energy absorption cap.

k,2 The ,012 Alclad 202U-T3 skin on the inner face of the rear

energy absorption cap was omitted.

U,3 "Hie skin around the edge of the rear energy absorption cap was

overlapped onto the cylinder 1/2".

5. TESTING OF CAS£ HIL-T-UTT

5.1 hydrostatic Pressure Test - 12 psi

A diagraa of Case HXL-T-1*?? Is shown In Figure 3. The proto-

type locking deTice was used in the front end cap. See Figure 2

for details.

Strips of blotter paper were placed inside of the hydrostatic

• cylinder as was done on Case HTL-6-U77.

The gage pressure was cycled fron zero to 12 psl* twice. The

pressure was held at 12 psi for 'j minutes at the end of each cycle.

•The pressure reached 13 psi during one cycle.

«•xcel Research COITRACT «0# nA-OU-200-AMC-V77(A) Reference; 6065

Ro noticeable pressure drop occurred at any tlae duriog the test.

The front and rear end caps and the cylinder energy absorption

core becajae partially filled with water during the test« After the

speciaen was removed from the pressure tank, the front end cap vas

renored. Thor« was no water In the bot to» of the hydrostatic cyl-

inder .id no dsjspoess In any of the pieces of blotter paper.

There vaa no indication of skin buckling or daaage to the seaas

or Joints on the inside of the hydrostatic cylinder. A pattern of

longitudinal vrinkles occurred in the energy absorption cylinder

stln orer each circumferential core cutout. The vrinkles we.« ap-

proocimately uaiforaly spaced around the circumference of the cylinder.

The edges of the front and rear end caps had similar patterns of longi-

tudinal vrinkles extending around the circumference of the caps. The

circumferential skin Joints opened intermittently. ,

5.2 Evaluation of Hydrostatic Pressure Test Reaulta

No leakage Into the inside of the hydrostatic cylinder occurred v

during this test. However, leakage past the seal ring occurred during

the test on Case IlXL-6-^77. The probable cause of the different re-

sults of the two tests is that the plastic seal ring used during the

test on Case HJL-6-^77 appeared to be faulty and was replaced prior

to the test on Case HXIr-7-^77.

Hexc«l Reittarch Refitrenc«: 6065

COiTRACT HO. DA-0»4-200-AMC-i»77(A)

TABLB I

QOWARISOH OF VIDPATIOW TEST RESULTS OH CASES

VERTICAL AXIS YTBRATIJN TB8T a)Par*lltl to vibration

^tU-AceclerQMtfcr/te

TE3T ■■ PEAK MUMREP

b)Perpendicular to vi- bration axis - Accellb

CAgj Kjggj^rf

fREQUENCY (CPS)

JL

1 ?

1214 19^

122 19U

ACCSL,

12 J8

38

3lL

CASE H3

FPfqiinicY (CPS")

115

115

ACCBL,

18

12

LOIKWUDIHAL AXIS yiBRATIOH ISST a)Parallel to ribration

axis - Accel.lb 1 2

k2 60

121

30 25 »♦6

b)Perpendicular to ▼1 bratIon axis -

125 1? 0»4 .2ä~~i •Peak #1 on each set of data has similar frequencies for the two Cases.

••Acceleroasters for Case aXL-5-^77 vere located as shown below. The arrows

indicate the direction along which each accelemoaoter neasured g values.

See Progress Report ^6 for acceleroraeter locatioaa for Case UXL-Ji-J*77«

&» t\ (*\ % V

ic

l\>

csr.

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II—

H«K«1 Re »«arch OOiTRACT »0. DA-04-200-AMC-Jirr( A) Refsrenc« t 6065

ATTÄCHWMT #1

ATTACHM8HT 01

LTATEMKMT OF MAN HOURS EXPSNDSD - JULY 19Ch

KngineeriDg:

Sr. Professional 55.0 Profistlonal 181.5

Technician:

drafting, fabrication, & testing lift.5

Other:

Clerical U.Q

TOTAL HOUHS KXPKMDfciD 359.0

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MBchlne Schrew (Sealed vith futty)

Plwtlc Shire Locldn^ Device

^ Front

Frvtr^r Absorption Coro

Rytiroartatlc Cylinder

.

FIDDRE 2

HYDROSTATIC PRESSURE 5EALIND CASSS HXI^6^77 AND HIL-7^77

l]S Tl» seal ring consists of a Plastic Ring of rectangular cross-SBCtion and a rubber back-up ring»

Ifot to Scale «/n/61i F.F.

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BLANK PAGE

HiEXC E L- BERKELEY, CALIFORNIA

REFEREHCB; Rfcp 606$. Ooatract Ifo. DA-Oi*-200-AMC-^7T(A) — ii

._i-

■ -+ M -- 4-4—f

I-

i

4—H _. -^—4

B. AntlyiiB

A. H^droatatlc Prei«ur» (12 p«l)

TBSTIIIC AT OIIOIJY (HXL-7^771 _

D, Analyslt

C, Fl«t ^rcip B. End Drop

A. .Hydro«t«Uc Presenf (^ pal)

TSSTIWO AT BERKBIZY (HXL-6-i»77) CASE FABRICAnOi (HXL- 6*7 -^77)

DBSIGII »»DlflCATIOII (HXL-6 k 7 -i»77)

DBLIVIW 10 PICATHIX («11^5-^171 _ B, Analysis

A. Vibration

TigTIHG AT BElRgLEY (HXL-MTT)

PROGRAM OF EVENTS

"t -+—

! M ' M : 1 | -4- ♦ - -4 .- +- -t t 4-—I

-f-i 4-4- - t--^ -4- 4 r

♦ r ' -♦ 1 - +—i i ;

-f- -^ -■' * - 4- — ♦

4-- ^ i i

1" »—

i

i

t" 14-

-I- -*. . + 4- f--

4 -r-

f.4- 4. ; T 4-- ♦ * . f- t +

-f-f ■-f

• —-r j- i-i-t--!-L.

1-4--t 1 t 1 ■■ 4 - 1—1-4-4 -4— i

__f-4-f-.l_ . f-4-|-4- I- -4-

■■■■ ■

ARCM ATTACHHDTT # 2 CURKKIT PROGRBSvS JULY 190*

MEXCE RE S E AF BERKELEY, CALIFORNIA

REFERgMCE; RfcD 6063. Oootrmct Bo. DA-OU-gOO-AMC-JtTTtA)

W&ICl WODIFICAnOH (HXI^IO^TT)

• . Analriia d. Drop Tests

c. Hydrostatic Pressur« Test (22 psi)

_b' Y^ftloa T9»t (D-V)

%f_Wjst Drop Tsst

TESTIIO AT BKHdlJUf (HXL-^TT)

CA3B PABRICATIOI (HXL-9-^77)

EKSIOI HDDIFICATIOII

f. Analysis

«. Drop Tests

d. Hydrostatic Pressure Test (22 psi)

c. Flat Drop Test _

b. Vibration Tsst (IVV)

%• Teaparrtnra - Shock Test (D-V)

WSTIHG AT BBWSLXY (HZL-d-^TT)

CASE FABRICATK» (HIL-^^77)

DtSIOl MDDIFICATIOB {HTL^S-hlD

a. Flat Drop

TK3TIia

. A» Aatlyeii ct Hydrostatic Pressure (22 jeil

b. Bd^s Drop

ggflig AT BiaaSLlT (HIL-7^77)

4« Analysis

J5x Hydrostatic Pressure (22 psi)

bj Flat Drop

», ted Drop

PROGRAM OF EVENTS MONTHS AUGUST 1961»

L

RC M Attachwnt I 3 PROGRAM OF EÄSUIHG ACTIVITIBS AUGUST k SEPT8MBBR I96U

— — —. -

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SKPTSMSBR 196^