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UNCLASSIFIEDAD NUMBER

AD376888CLASSIFICATION CHANGES

TO: unclassified

FROM: confidential

LIMITATION CHANGESTO:Approved for public release, distributionunlimited

FROM:Distribution authorized to U.S. Gov't.agencies and their contractors;Administrative/Operational Use; 31 AUG1966. Other requests shall be referred toArmy Combat Developments Command, FortBelvoir, VA 22060.

AUTHORITYOACS FOR, D/A 13 Sep 1973; OACS FOR, D/A30 Sep 1978

THIS PAGE IS UNCLASSIFIED

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mom, CAN

GENERALDECLASSIIC'ATIONjSCHEDULE'INCCORDANCE WITHOil 5208,1k & XECITIVE BRIE1 11652THIS DOuCUMENT Is:CLASSIFIED BYi-. .Subject to keral leclassificatsmp Schedult of

Executive Order 11652-Automatically Downgraded at2Yms strvais-,JECLASSIFIED ON DECEMIER

114041

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SECURITYMARKINGThe classified or limited status of this repoit appliesto each page, unless otherwise marked.Separate page printouts MUST be marked accordingly.

'PHIS DOCUMENT CONTAINS INFORMATION AFFECTING THE NATIONAL DEFENSE OTHE UNITED STATES WITHIN THE MEANING OF THE ESPIONAGE LAWS, TITLE 1U.S.C., SECTIONS 793 AND 794. THE TRANSMISSION OR THE REVELATION OITS CONTENTS IN ANY MANNER TO AN UNAUTHORIZED PERSON IS PROHIBITEDLAW.

NOTICE: When government or other drawings, specifications or otherdata are used for any purpose other than in connection with a defi-nitely related government procurement operation, the U. S. Governmethereby incurs no responsibility, nor any obligation whatsoever; andthe fact that the Government may have formulated, furnished, or inway supplied the said drawings, specifications, or other data is notto be regarded by implication or otherwise as in any manner licensithe holder or any other person or corporation, or conveying any righor permission to manufacture, use or sell any patented invention thmay in any way be related thereto.

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CONFIDENTIAL0000 ARMY OJJGM TA4 IB'A00 APO San ftancisco, 96243

BAR ARMOR KIT(MI13) (U)

*Tis document contains 4 for -tion affecting the NationaDefense of the ikil'" - n' ViJo merinng of th3 JEspionage Laws, Tit ,L U. f. C., ['. tion 793 an d 794.,Its transmission or tho r3:e*ltion cf its contents in anzwanner to an unauthorzied person is prohibited by jaw' J

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CONFIDENTIALJOINT RESEARCH'AND TEST ACTIVITY

Office of the DirectorAPO 9636"REPORT EVALUATION BY DIRECTOR,

JRATAThe inconclusive findings as regards to the capability of the

Bar Armor to defeat enemy 57mm and 75mm HEAT rounds is normal totesting in a combat environment and should not be weighed againstthe Bar Armor concept. More significant to this evaluation is therestrictions imposed on the M-113 as a result of increased size.Restrictions on bridge access and maneuverin&gwithin areas such asrubber plantations reduces the combat effectieness and utilitv ofthe M-113. These restrictions probably more than offset theadvantage of increased protection provided by the Bar Armor Kitin its pre.sent configuration.

I concur with the recommendations of this report.

Approved:

15 Septenbe 1966 CHARLES E. HLAMMETTColonel, USAFActing Director, JRATA

Regraded unclassifiedwhen sepamted frmclasaified inmlofar

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CONFIDENTIALARMY CONCEPT TEAM IN IETNAMAPO San Francisco 96243

FINAL REPORT

BAR ARMOR KIT(M113) (U)JRATA Project No. 1B-172.0

31 August 1966

Approved:

MERRILL.G. HATCHColonel, ArtilleryChief

0IJ RADXD- AT-- 3-EAR INTERV!%S'I DECLASSIFIED AFTER 12 YEARSDOD DIR 5200,.10

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CONFIDENTIALSUIMARY

B6iL-on uparworing kits fashioned from rods and bars designedfor the M113 armored personnel carrier in such a way as to de-tonate a HEAT round before the full force of the je t strikes the APCbody were evaluated in combat operations in the Repub.. .. f Vietnam.An increase in width and length of APC's equipped with bar armorkits restricted movement across bridges, canals, and plantation areasthat would normally be accessible to the standard APC. No actual

*combat data were obtained on the capability of the kits to defeat*HEAT rounds because the test vehicles were not fired on. Kits werevulnerable to damage from vibration and from hitting obstacles,It is recommended that, because of their design deficiencies,

bar armor kits not be employed in Vietnam.

ii

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CONFIDENTIALARMY CCZCEPT TEAM IN VIETNAMAPO San Francisco 96243

ACTIV-GCD 31 August 1966

BAR ARMOR KIT (MI13) (U)

I. (U) REFE iCE..a. Letter, Headquarters USAMQ, 7 October 1964, subject:Feasibility of Uparmoring. the M1 13 Armored Personsl Carrier (APC).

b. Letter, Chief ACTIV, I July 1965, subject: Armor Pro-tection. Kit for the MI t3 Armored Personnel Carrier.

c. Message, USAMC 8-2007, subject: Shipment of Armor Kitsfor M113, dated 25 August 1965.d. BRL Memorandum Roport 1725, dated December 1965.

2. (U) UTHORITY..Letter, AGAM-P(M) (17 Ju l 64) ACSFOR, DA, 31 July 1964, suh-

ject: Army Troop Test Program in Vietnam (U), as amended. CINCPACMessage,. DTG 050541Z January 1966.3. (U) PURPOSE

Th e purpose of this evaluation was to determine the suit-ability of a bar armor kit for the M113 and to recommend a basis ofissue..4. (0) BACKGROUND

The Viet Cong (VC) insurgents optrating in the Republic ofVietnam (RVN) use 57mm and 75mm recoilless rifles in addition torocket launchers, The rocket launchers include 2.36 inch and 3.5inch US models and the Russian 82mm model.

CONFIDENTIAL

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CONFIDENTIALThese weapons fire high explosive anti-tank (HEAT) ammunition thathas been effective in .penetrating the aluminum.armor of-the M1113armored personnel carriers (APC) used by the Army of the Republic ofVietnam (ARVN) armored cavalry squadrons,

In July 1964, the United States Army Materiel Command (USAMC)investigated the feasibilLy of uparmoring the M113 to defeat 57mmand 75mm iX T ammunitiono Recommedations were made against thisuparmoring by USAMC but the problem -continued to be investigated bythe Ballistic Research laboratory (BRL)..In April 1965, after exhaustive tests as to its effectiveness

and suitabij.ity, _BRL recommended that panels of bar armor be fabri-cated in test quantities for evaluation as a solution to defeatingthe HEAT ammunition (see Ref. id).The US Army-Tank Automotive Center (USATAC.)-then fabricateda prototype bar armor kit , demonsti-ating the feasibility of the con-cept, and.-in July 19659 the Army Concept Team in Vietnam (ACTIV) re-

quested a quantity of the bar armor kits be shipped to Vietnam forevaluation.

USAMC approved the production of an evaluation quantity ofeight bar armor kits and they were shipped to Vietnam on 20 August1965.Seven bar armor kits were installed on 44-.3 armored per-sonnel carriers and one on a M132 mechanized f'lamethrower (M113basic chassis) by the 80th Ordnance Rebuild Base Depot (80ah ORBD),

between 8 October 1965- and 16 December 19&5oThe seven.M113's with bar armor kits were issued to the 10thArmored Cavalry Squadron for evaluation, Th e tactical area of re-sponsibility for the 10th Armored Cavalry Squadron during the periodof the evaluation irluded al heavily jungled area-of- Ta y Ninh Pro-vince; Long AniPxovince, which has a network of small streams andcanals; and the rice paddy and rubber plantati6n areas of Hau Ng4iaProvince, which was tht principal area of operations,The kit installed on the M132 remained at the 80th ORBD fora considerable period of time because of technical-difficulties con-cerning the flamethrower-and, as a result, was not eVajUatedo "How-e:er, since the conclusiorr of the eyaluation period, the Mi32 has beenemployed in combat operations. ACTIV will continue to monitor the useof this vehicle'oRecords maintained by the 80th ORBD indicate that approximately105 man hours were required to install each bar armor kit, The bar ar-mor kits were evaluated from 15 January through 15 April 1966.

2

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CONFIDENTIAL5. (C) ISCUSSION

ao qhjjive 1- Protection Capabilt"Determine if the bar armor kit is effective in de-feating the 57=m and 751nm HEAT ammunition used by the VC."The 10th Armored Cavalry Squadron engaged in approxi-mately 36 combat operations during the evalation. The majority of

these operations were road security, vehicle convoy security, andstatic blocking positions in conjunction with search and destroymissions in which contact with the VC occurred on 10 occasions.These contacts were apparently limited to small arms fire and sniperfire and the bar armor kits were not hit by 57mm or 75mm HEAT rounds.The flotation boxes and the side grille frames received some minor,damage as a result of the small arms fire.

b,, Ojective 2 - Effect on Performance of tle'111"Determine if the weight or physical characteristics of

the bar armor kit degrade the performance of the M113 and determine ifthe bar armor restricts the mobility of the M113."

The bar armor kit as presently designed fo r the M113 APCis cumbersome and bulky. (See figure 1) The center front -grilleframe extendsapproximately 14 inches in front of the leading edge ofthe vehicle. This requires the driver to approach a ditch with muchmore caution and at a slower speed than he would without the kit to besure that the center front grille- frame does no t strike the bank be-fore the tracks can grip the soil. If the center front grille framestrikes the bottom of the ditch -even at very slow speeds, the grillewill bend and the front bumper plate support brackets may crack. Ifthe grille is bent, the J bolts either snap off or become loose andthe grille bars fall out,

The width of a M1 13 APC without a bar armor kit installedis 105-3/4 inches. Minimum width, less the track shroud is 100inches, An M113 equipped with a bar armor kit in the unextendeaposition is 112 inches wide. This increase in width becomes a factorlimiting performance because of the width of the Bailey-typ- bridgesfound on the primary and secondary road nets in Vietnam. On twooacasions during the evaluation period, vehicles with bar armor kitscould not cross Bailey-type bridges in the area of tactical operationsbecause the bridges were no t wide -enough. Since these bridges haveelevated steel sidings, there is no way to-overcome the'problem of th ewidth of the bridge, such as there might be on a bridge with nosidings, where the track of the vehicle could extend beyond the edgeof the bridge roadway.

3

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LOCKINGRIGHT SIDE BRACKETS

SUPPORT ARMUPPERAND BRACKETS

GRILLRAME

GRILLE FRAME

PPRSPOARM AN

SUPPOLORE SUPPOR ARM OND EATTAHINGBRAKETSATTAHIN BRAKETFRONTFLOT71ONBOXE

CENTER.1! workt~vzpneisFRONT RIGH

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CONFIDENTIALThe bridges found on primary roads are usually wide enoughto accept the vehicles with bar armor kits but bridges on secondaryroads are smaller and narrower an d have been repaired frequently. It

is not uncommon to see normal M113 APC's with scrape marks extendinithe length of the vehicle. By-passing these narrow bridges is notan acceptable solution for-two reasons. First, many times the oanksof the streams are too steep or the speed of the water is excessive.Second, the time it would take to find and clear a fording site forvehicles with bar armor kits might jeopardize the accomplishment ofthe unit tactical mission.

When the left and right side grille frames are extended,each frame is approximately 14 inches from the side of the vehicle,which increases the overall width of the vehicle to approximately 128inches. This additional width does not cause any loss of mobility inopen terrain but, when the M113 is operating in high grass cr rubberplantations, the driver must look not only to the front for obstaclesbut must also watch for obstacles that could strike the grille frames.Turning from one lane to another within the rubber plantation is moredifficult and must be done at slow speed because of the width of thevehicle and the danger of damaging uhe grille frames by strikingrubber trees.

During the evaluAtion no opportunity for deep waterswimming presented itself, so a separate test was made. One of thebar armor kits was damaged when the vehicle on which it was mountedstruck an anti-tank mine. (See figure 2.) The right side grilleframe and flotation boxes were repaired and replaced by the 80thORBD. Records indicate that 105 man-hours were required to repairthe kit, Because this was a major reir of the kit, a swimming testwas conducted to insure that the-vehicle could swim with the repairedkit. Th e vehicle entered the water with no difficulty and maneuveredfreely. It was slightly nose heavy but there was no loss of swimcapability.

51

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CONFIDENTIAL

(U) FIGURE 2. Damage to bar armor kit by mine of undetermined size.Since the conclusion of the evaluation period, twoadditional vehicles with ba r armor kits and Tiring observation portshave been rece.ved by ACTIVo Initially, these two vehicles wereabdigned to the 2nd Armored Cava2ry Squadron located in the Delta areaof Vietnam. It was necessary, however, fo r the conander of the unitto have the bar armor kits removed so that he could cross the bridgeslocated in his tactical area of operations. As a result, the vehicleswere reassigned to the Ist Cavalry Squadron in the II Corps area northof Saigon.c. Objective - Equipment Faults

"Determine if the ba r armor kit has any deficiencies,shortcomings, or limitations which may degrade its capability."

6

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CONFIDENTIAL(1) Deficiencies

During the e-valuation of the bar armor kits, noequipment deficiencies were apparent.

(2) ShortcomingsThe following shortcomings were noted during the

evaluation:(a) Locking Bracket Pins. The locking bracket pins

seize in the locking bracket and are difficultto remove in order to extend the side grilleframe. (See figure 3.) The cause of this short-coming appears to be twofold: first, the accu,-mulation of dirt and moisture in the lockingbracket hole; second, misalignment of the sidegrille frame in relation to the locking bracket,caused by vibration and impact during normaloperation of the vehicle.

(b) Front Bumper Plates, If the front bumper platesstrike an obstacle they have a tendency to sheartheir retaining bolts and freeze in a partiallyretracted position, (See figure 4o)

(c) Front Bumper Plate Support Bracket. The frontbumper plate support bracket develops cracks atthe point where it is bolted to the hull of thevehicle. These cracks are caused both by vi-bration and impact of vhe front bumper againetobstacles, (See figure 5.)

(d) J-Bolts. The J-bolt nuts which secure the J-boltand the steel bars to the grille frames becomeloose because of vibration of the kit during normalcross-country oridration. Considering that thereare 424 J-bolts. an excessive amount of curewmaintenance is required to keep the J-bolt,' andnuts secure.

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(U) FIGURE 3. Removal of locking pin from side grille frame lockingbracket

-A

(U) 4IGURammed front bumper plate in partially extendedposition.

8

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CONFIDENTIALAPC USA No. 80945

(a) Front bumper plate support bracket - cracked.(b) Right front bumper plate - missing.(c) Right upper support arms - broken (figure 6).

APC USA No. 81i85(a) Front bumper plate support bracket - cracked.(b) Side grille frame locking pin - missing.(c) Lower support arms, right side - broken (figure 7).(d) Right side grille frame - bent (figure 8).

APC USA No. 80952(a) Front bumper plate support bracket - cracked.(b) Side grille frame mounting brackets - cracked.(c) Right center grille frame extension arm - broken.

(d) Right front bumper plate - jammed.

10

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Nm' - 11 U-

(U) FIGURE 6. Broken upper support arms.

(U) FIGURE 7,Broken lower support arms.

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CONFIDENTIAL

1 !16

p

(U) IGURE 8. Bent, right side grille frame.APC USA No, 8iM,2

(a) Center front grille frame - bent (figure 9).(b) Left side grille frame - bent.(c) Front bumper plate support bracket - cracked.(d) Upper and lower left support arms - broken.

APC USA No. 809 1(a) Front mounting brackets - cracked.

APC USA No. 81264(a) Left-side grille frame - bent.(b) Left and right side grille support arms - broken.

APC USA No . 80947(a) Left and right' grille support arms - broken.(b) Left and right front bumper plate - jammed.

12

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CONFIDENTIAL

(U) FIGURE 9. Bent center front gri-U fi'ame.At the conclusion of the evaluation period all of th e M1136

with bar antor kits installed ..are operational but with daffia tothe kits as described above. Ai l inspection team fr'om the 80th ORAbbvisited the 10th Amored Cavalry Squadron to determine the extent ofdamage to the armor kits. Listed below is an estimate of the manm-hours required for repair of the kits:Vehicle No . Type of Damage Pat_,H-7tlts80945 Non-combat 4580947 Non-combat 4080951 Non-combat 280952 Small arni fire damage 20and non-combat81185

Non-combat 881264 Non Combat 1081722 Non-combat 65

TOTAL 262

"tRecommenld what the basis of issue should be for ARVN=nits."

13

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CONFIDENTIALSince the bar armor kits were not hit by 57mm or 75mM

HEAT rounds during the evaluation,, and in view of the damage to thekits by tactical movement, there is no foundation in data or pro-fessional judgement upon which to base a recommended basis of issue.6. (C) FINDINGS

a. Because of the lack of frequent enemy contact during theevaluation, an d the fact that when contact was made enemy fire waslimited to small arms, no determination could be made as to the pro-tection capability of th e bar armor ki t against attack by 57mm or75m, HEAT rounds.

b. The increase in overall width of.the M113 with a ba rarmor kit installed degrades the performance of the vehicle by re-quiring the driver to drive slowly and cautiously in an effort tominimize damage to the front and side grille frames which would becaused by striking obstacles to the front or sides of the vehicles.

co The bar armor kit is subject to damage from normalvehicle vibration during cross-country movement and the front andside grille frames cannot withstand impact with obstacles thatotherwise do not affect the movement or combat capability of theM113 APCo7. (0) CONCLUSIONS

a, Because the bar armor kits were not hit by 57m or75mm HEAT rounds, no valid conclusions can be arrived at as to thecapability of the kit to defeat these weapons.b. The bar armor kit as presently designed and con-structed is not durable enough for combat operations in Vietnam.

8. (c) RECOMMATIONIt is recommended that the bar armor kit for the M113 ar-mored personnel carrier not be made an item of issue for ARVN or

US units in Vietnam.

1

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DISTRIBUTIONDepartment of Defensa

Director of Defense Research. nd .Engineering, 1Department of Defense

Advanced Research-Projects Agency, Office of the- ISecretary of DefenseChief, ARPA R&D Field Unit, Vietnam, 2

Chief, ARPA R&D Field Unit, Thailand IDefense Documentation .Canter 20Joint Chief i of Staff

Chairman, Joint Chiefs of Staff, ATTN: SpecialAsat for Counterinsurgency and..SpecialActivities.,Zepartment of Defense

Unified and Jaint Commands, MAAGS. aad MissionaCommander-in-Chief, Pacific 2Commander-in-Chief, US Strike Command 1Commander, US Military Assistance Command, Vietnam 6(J-1, J-2, J-3, J-4,.-J-5, J-6)Chief, Joint US Military Advisory-Group to Thailand 1Commander-in-Chief, Southern Command IDirector, Joint Research and Test Activity 6(For official distribution to COMUSMACV and CINCPAC)

United States ArmChief of Staff, Department of the Army IOffice of the Chief of Staff, Department of the Army, 1'ATTN: Special Assistant fo r SpecI4 Warfare

Activities I I ..Deputy Chief of Staff for Logistics, Department of the 2ATmyDeputy Chief of.-Staff fo r Military Operations, De- 5partment of the Army --Assistant Chief of Staff for Force Development, De- 10partment of the ArqrOffice of the Assistant Chief of Staff for Force 10

Development, Depa-rtmerp. of the Army, ATTN:ACTIV Liaison -Officer:Chief of Research and Devlpnent, Department of the 3Army, ATTN: Specia3Warfare DivisionChief of Research and Developmert, Department of the 1Army, ATTN: Director of Army Research

A-I ANNEX A

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Chief of Research and Development, Department ofthe Army, ATTN: Director of DevelopmentsCommanding General, JS Army Materiel Command 45

Commanding General, US Army Materiel Command 5ATTN: Director of Research and Development (AMC RD)Commanding General, US Army Materiel Command 5ATTN: Project Manager, Special Warfare (AMCPM-AI)Commanding General- US Army Mobility Command 2Commanding General, US Continental Army Command 30Commander-in Chief, US Army Pacific 5Commanding General, US Army Combat Developments Commnd 60Comnanding General, US Army Combat Developments Command, 5Director of EvaluationCommanding General, US Army Combat Development Command, 5ATTN: Special Warfare Group (SPWAR & CA GROUP)Commanding Officer, US Army Combat Developments Command, 5

Iniantry AgencyCommanding Officer, US Army Combat Developments Command 5Special Warfare AgencyCommanding General, US Army Cobat Developments Command 5Experimentation Center

Commandant, Command and General Staff College 2Commandant, US Amy War College 2Commanding General, 1st Cavalry Divisi6n (Airmobile) 5Commandant, The Infantry School, ATTN: AJIIS-A 3Commanding General, US Army Engineer School 5Commanding General, US Arm Special Warfare School 2Commanding Officer, US Army Limited War Laboratory 2Deputy Commanding General, US Army, Vietnam 20Commanding Officer, US Army 5th Special .Forces Group, Vietnam 10Commanding General, USAREUR, ATTN: G-3Commanding General, Seventh US Army, ATN: G-3 1Commanding General, US Arn7 Test & Evaluation Command 2Commanding Gencral, John F. Kennedy Center for Special Warfare 1President, US Army Infantry Board 2Commanding General, XVII Airborne Corps 2Commanding Officer 1st Special Forces Group 2Commanding Officer 10th Special Forces Group 2Commanding Officer 8th Special Forces Group 2Senior'US Advisor, each ARVN Corps 2Senior US Advisor, each ARVN Division ICommanding General, US Field Forces, Vietnam 5Commanding General, 173d Brigade 5Commanding General, 1st Infantry Division 5Commanding General, 25th Infantry Division 5Commanding Officer, 1st Brigade, 101 st Airborne Division 5

ANNEX A A-2

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United States Marine Corps /Commandant, US Marine Corps IDeputy Chief of Staff (R&D), Hq, US Marine Corps IAssistent Chief of Staff G-3, Hq, US Marine Corps IDirector, Marine Corps Landing Forces Development 1CenterCommanding General, II Marine Amphibious Force 5

A-3 ANNEC A

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CONFIDENTIALSedurity Classification DOCUMENT CONTROL DATA -R&D

(Security claelilcation of title, body of abstract and indexing annotation must bc enteredi when the overall report Is classified)I ORIGINATING ACTIVITY (Corporate atithor) 28 RCPORT SECURITY C LASSIFICATIONArqy Concept Team in Vietnam[ CONFIDENTIAL

APO San Francisco 96243 2b GROUPo .___ ___ ______ __ __ _ ___ ___ _ _ ___ Group 4.3. REPORT TITLE

BAR ARKOR KIT (Mll3) (U)4. DESCRIPTIVE NOTES (Type of report and Inclusive dates)FINAL REPORT - 15 January to 15 April 19665. AUTHOR(S) (Last name. first name. initial)

Callahan, Robert F., LTC, Armor6 REPORT DATE 7a TOTAL NO OF PAGES 7b . NO OF REPS31 August 1966 14 Noneaa. CONTRACT OR GRANT NO . 98. ORIGINAT',Z S REPORT NUMSER(S)

None Noneb. PROJECT NO .C. 9b. OTHER REPORT NO(S) (Any other numbers that may be assigned

this report)d. JRATA Project Number 1B-172.O

10. A VA IL ABILITY/LIMITATION NOTICES

Qualified requestors may obtain copies of this report 'rom DDC.II. SUPPLEMENTARY NO CES 12. SPONSORING MILITARY ACTIVITYNone Combat Developments CommandFort Belvoir, Virginia

13. ABSTRACTBolt-on kits constructed of iron bars strung on iron frames were producedto uparmor the M313 armored personnel carrier to defeat 57 and 75 mm IVTrounds in combat operations in the Republic of Vietnam. The kits were no tstruck by HEAT rounds during the e~aluation. Even though armoz'ring capabilityof the kits was not obtained, it was determined that the kits %ere not suitablefor combat operations in Vietnam because they were not durable enough. (C)

FORM IDD I JAN S t1473Secu'rity Classification

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LA SSTT FDSecurity Classification________________14KYWRSLINK A LINK B LINK C

____ROLE W1 R OLE W RO0L E W TM113 armored personnel CarriersBar armor :ttsCounterinsurgenicy environment, Vietnam

INSTRUCTIONSi*ORIGINATING ACTIVITY: Enter the name and address imposed by security classili,_ ition, a'. og standard statementsof the contractor, subcontractor. grantee, D~epartment of De'- such astense activity or other orgarization (corpora:e author) issuing (I) "Qualified ri-quester& ma obti n c, pies of this;the report. report from DDC."

2a. REPORT SECURITY CLASSIFICATION: Enter the o)ver- (2) "lXore,~'n atnn-uncemeiit and dp seniration of thisail security cOassificatiori of the report. lndu~ate whether rpr vDCi o uhrzn"Restricted Data" Iisij.c'u-jed. Marking it, tc be in accord- rp r e D C i o ihrzoance with )~pe~opriate sci.urity regulations. (3) "U S. Government a..tencies nie et, ,tri (opies ofIthis report directly fromt DDC. Ott r qualified DDC2b. GROUP: Automatic downgrading z sIpec fied in Dot) Di- Users tshall request throughrective 5200. 10 .ind Armed Forces Industrial Ma.nual. Entertha roungshaeben ulseor Groupn ndaberow thas author-()n.Salltr gnie ba n pe ftithekigrou numebe. Alseo. he uppliable shoup that autional)".S iiar gnismyotan(pe ft iized report directly from DDC. Other qualified users3. REPORT TITLE: Enter the complete report title in all shall request throughcapital letters. Titles in all cases should bt unclassified.IIf a meaningful title cannot be selected withut classifica- ____________________tion, show title classification in all capitals in parenthesis (S) "All distributioii of this report is controlled. Qual-immediately following the tit e. ified DDC users shall request through4. DESCRIPTIVE NOTES: If appropriate, enter the type of-_______________ Ireport, e.g., interim, progress, summary, annual, or final. I h eothsbe unse oteOfc ehiaGive the inALsive dates when a specific reporting period is- Servicer, Department of Commerce, for sale to the public, tndi-covered. atos)a hwon cate this fact and enter the price, if known.exlaa5. AUTHOR(S): Enter the name(s) of auhrs s-hw n 11. SUPPLEMENTARY NOTES: Use for additionol epaaor .the rer"~rt. Entet last name, first name, middle initial, tory notes.If rmltary, show rank and branch of service. The name ofthe prinv ipal author is an absolute minimum requirement, 12. SPONSORING MILITARY ACTIVITY: liter the name of

6. RP3R DAT.te ! he ateof te rportas ay, the dep~artmental project office or laboratory .iponsoring (pay-6. RP )T DTE.Entre da e o th reortas ay, irig for) the research and development. Include address.month, year. or month, year. If more than one date appe arson the report, use date of publi. ition. 13. ABSTRACT: Enter an abstract giving a brief and factualsummnary of the document indicative of the report, even though7a. TOTAL NUMBE~R OF PAGES: The tot,,l pape count it ma y also appear elsewhere in the body of the tL-chnica! re-should follow normal pagination proceoures, i.e., enter the port. If additional space is required, a continuation sheet shallnumber of pages containiing information, he attached.7b. NUMBER OF REFERENCES. Enter the total numbe, of It ti- ighly desirable that the abstract of classified reportsreferentcs cited in the report. be unclassified. Each paragraph of the abstract ;hall end with8a . CONTRACT OR GRANT NUMBER: If appropriate. entcr ain indication of the military security classification of the in-the applicable number of the contract or grant under which formation in the paragrapri. represented as (TS.' '(S) (C) -r (U)the report was written, There i% no limitation on the length of the abstract How-Sb, l&, & 8d. PROJECT NUMB"tR. Enter thc- appropr:,ite cvfcr, thte s uggestIed length is from 150 to 225 wordsmilitary department idfentificateon, such as project tiunmht,-r 4KYWRSKe usart'inalymangutrssubproject number, systrm numit~ers, task number, etc. 1 E OD.Kywrsaettlnclymaigu emor sotphrases that c-ha acter~ze a report and may bc ased as9a. ORIGINATOR'S REPORT NUMBER(S): Enter tie offi- :,cx entries for catal ,ing the rep-( Key wor,.,, must becial report number by which the document will be ideiited selected so that no Se't urity classificat,"n is rettited Identi-and controlled by the originating a~tivity. fiiis nuit1 er must fiers. such a-' equipme~i! model designa!''n. :!-ad, name, militarybe unique to this report. Ipoijq-t code. ".nimc, ge-V-aphtc lot alien. mnay lie u-4 aa key9b. OT'HER REPORT NUMBER(S): 1: the report 1, s tbeein word,; but will be -lt )wtdi by in aniition of technieca-assigned any other report numbers (vih.rb th ) nfor text 'Me assignm' ni of links. rales, ant, weights is otoaor by the sponsor), also enter this numbeN)10. AVAILABILITY/LIMITATION NOTICES: Etr ay !',n-itat ions on further dissemination of therlrt oh- tn it .NLSSFE I

Security Classfication

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DISCLAIMER NOTICETHIS DOCUMENT IS BEST QUALITYPRACTICABLE. THE COPY FURNISHEDTO DTIC CONTAINED A SIGNIFICANTNUMBER OF PAGES WHICH DO NOTREPRODUCE LEGIBLY.