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0

.DECLASSIFIED BY AF/1101l'AW E.D.12958 (AMENDED)DATE 20080718APPROVED FORPUBL I C RELEASE

PROJECT

SOUTHEAST ASIA

DECLASSIFIED BYRICHARD DAVIS, AF/CHOR

15 October 1985

* j GROUP-1Excluded from automatic downgradingEand declassification.

K717.0413-C86c.-2 CONF!IENTIAL

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0 DEFENSE TECHNICAL INFORMATION CENTERhnfrri,,wfor t Oef&ue.Cswauty

Month D YearDTICha determiedon LLO I ,~~hthat this Technical Documenthas the Distribution Statement checked below. The current distribution for thisdocument can be found in the DTIC Technical Report Database.Z DISTRIBUTION STATEMENT A. Approved for public release; distribution isunlimited.[-- @COPYRIGHTED. U.S. Government or Federal Rights License. All other rightsand uses except those permitted by copyright law are reserved by the copyright owner.F DISTRIBUTION STATEMENT B. Distribution authorized to U.S. Governmentagencies only. Other requests for this document shall be referred to controlling office.F DISTRIBUTION STATEMENT C. Distribution authorized to U.S. GovernmentAgencies and their contractors. Other requests for this document shall be referred tocontrolling office.R DISTRIBUTION STATEMENT D. Distribution authorized to the Department ofDefense and U.S. DoD contractors only. Other requests shall be referred to controllingoffice.D DISTRIBUTION STATEMENT E. Distribution authorized to DoD Components only.Other requests shall be referred to controlling office.El] DISTRIBUTION STATEMENT F. Further dissemination only as directed bycontrolling office or higher DoD authority.Distribution Statement F is also used when a document does not contain a distributionstatement and no distribution statement can be determined.F-1 DISTRIBUTION STATEMENT X. Distribution authorized to U.S. GovernmentAgencies and private individuals or enterprises eligible to obtain export-controlledtechnical data in accordance with DoDD 5230.25.

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N PROJECT,11III1It1111111111,hiiiiii* C on lemlpowar1 1"111II111111111H istorical ilIfIxamination of

Current0 erationsill 1REPORT

COMMANDO VAULT (U)12 OCTOBER 1970

HQ PACAFTactical Evaluation

CHECO DivisionI Prepared by:I MELVIN F. ORTER

Project CHICO 7th AF, DOAC

K717.0 4 13 -86

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UNCLASSIFIEDDEPARTMENT OF THE AIR FORCE

HEADQUARTERS PACIFIC AIR FORCESAPO SAN FRANCISCO 96553

rrICt T|I ( I41|| . .fAI

PROJECT CHECO REPORTS

The counterinsurgency and unconventional warfare environment ofSoutheast Asia has resulted in the employment of USAF airpower to meeta multitude of requirements. The varied applications of airpower haveinvolved the full spectrum of USAF aerospace vehicles, support equip-ment, and manpower. As a result, there has been an accumulation ofoperational data and experiences that, as a priority, must be collected,documented, and analyzed as to current and future impact upon USAF poli-cies, concepts, and doctrine.Fortunately, the value of collecting and documenting our SEA experienceswas recognized at an early date. In 1962, Hq USAF directed CINCPACAF toestablish an activity that would be primarily responsive to Air Staffrequirements and direction, and would provide timely and analytical studiesof USAF combat operations in SEA.Project CHECO, an acronym for Contemporary Historical Examination ofCurrent Operations, was established to meet this Air Staff requirement.Managed by Hq PACAF, with elements at Hq 7AF and 7AF/13AF, Project CHECOprovides a scholarly, "on-going" historical examination, documentation, andreporting on USAF policies, concepts, and doctrine in PACOM. This CHECOreport is part of the overall documentation and examination which is beingaccomplished. ong with the other CHECO publications, this is an authen-tic Tor sessment of the effectiveness of USAF airpower in PACOM.

e oMajor General, USAF[]c

UNCLASSIFIED

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'-. NFIDENTIALDEPARTMENT OF THE AIR FORCE

HEADQUARTERS PACIFIC AIR FORCESAPO SAN FRANCISCO 96553

REPLY TO

ATTNOF: DOVD 12 October 1970

SUBJECT: Project CHECO Report, "Comando Vault"To SEE DISTRIBUTION PAGE

1. Attached is a CONFIDENTIAL document. It shall be transported,stored, and safeguarded in accordance with applicable securitydirectives. Retain or destroy in accordance with AFR 205-1. Donot return.2. This letter does not contain classified information and may bedeclassified if attachment is removed from it.FOR THE COMMANDER IN HIEF

G IFFITH, onel, USAF 1 AtchChief, CHECO Division Proj CHECO Rprt (C),Directorate, Tactical Evaluation 12 Oct 70DCS/Operati ons C

CONFIDENIAL,

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UNCLASSIFIEDIST

1. SECRETARY OF THE AIR FORCE j. AFPDC(1) FDPXPS I....a. SAFAA ... ......... 1 (2) FDPMD 1....b. SAFLL .... ......... 1 (3) FDPW............ 1c. SAFOI .... ......... 2d. DAFUS ........... . 1 k. AFRD ................. 1(1) FRDP .. .. .. .. ... 12. HEADQUARTERS USAF (2) FRDQ.... ........ 1(3) FRDOPC 1....a. AFNB............. 1 (4) FRDR............ 1(5) FRDQL 1....b. AFCCS(1) FCCSSA ........1 1. AFSDC(2) FCVC .......... 1 (1) FSLP.... ....... 1i(3) AFCAV . ...... 1 (2) FSME. . .......... 1(4) FCHO . ...... 2 (3) FSMS............ 1(5) FCVD .........1 (4) FSSS............1(5) FSTP............ 1c. AFCSA(1) FCSAG.......... m. DA-AA.... ........... 1(2) FCSAMI ........... 1 n. AFXO ............

d. AFOA ............ 2 (1) FXOD .......... .. 1(2) FXODC 1........e. AFIGO (3) FXODD 1....(1) SIUAM.......... (4) FXODL 1....(2) GS ... ........ 1 (5) FXOOAB 1....(6) FXOSL 1....f. AFSG............. 1 (7) FXOOSN 1....(8) FXOOSO 1....g. AFNIATC ... ........ 5 (9) FXOOSS 1....(10) AFXOOSV I....h. AFAAC .... ........ 1 (11) AFXOOTR 1....(1) AFACMI ........ 12) AFXOOTW 1....

13) AFXOOTZ 1....i. AFODC (14) AFXOOCY 1....(1) FPRC . . ........ 1 (15) AF/XOX ........(2) FPRE .......... 1 (16) AFXOXXG........... 3(3) FPRM .......... 1

ivUJNCL,ASSIIFIED,

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II UNCLASSIFIED13. AJOR COMMAND b. SAC

a. TAC (1) EADQUARTERSI(a) DOPL.. .. .. .... 1(1) EADQUARTERS (b) PX. .. .. .....(a) O.. .. .. ..... 1 (c) M.. .. .. ......I(b) XP.. .. ....... 2 (d) IN..........(c) OCC........1 (e)OA..........(d) REA:. . *......... (f)HO.. .. .. .....

(e) ND. .. .. 1(2) AIR FORCES(2) IR FORCES (a) AF(INCS)......1(a) 2AF ( A(O1. OO.. .. .. ... 15AF(IN). .. .. ...(b) 9AF(IN).. .. ... 1 c. MACa(c)SAFSOF(DO) . . . . 1 ()HAQATR(3)WNS(a) DOI..........(a) 1SOW(DOI) .. .. .. 1 (b) OO .... .......(b) 23TFW(DOI). .. ... 1 (c) SEH.. .. .. ....(c) 7TRW(DOI). .. ... 1 (d) ACOA. .. .. ....(d) 3TFW(DOI). .. ... 1(e) 4TAW(DOI). .. ... 1 (2) IR FORCES(f) 7TRW(C). .. .. .. 1 (a) 22AF(OCXI). .. ....(g) 75TRW(DOI). .. ... 1I(h) 316TAW(DOP) . . . .1 (3) AC SERVICES(i) 17TAW(EX). .. ... 1 (a) WS(AWCHO). .. ... 1(j) 363TRW(DOI) . . . .1 (b) RRS(XO). .. .. .. 1(k) 64TFW(DOIN). . . . 1 (c) CGS(CGO) .. .. ...(1) 474TFW(TFOW). . . . 1(mn) 79TFW(DOI) . . . . 1(n) 516TAW(DOPL). . . . I(o) 4403TFW(DOI). . . . 1(p) 58TAC FTR TNG WG. . 13(q) 4554CCTW(DOI) . . . 1

(4) AC CENTERS, SCHOOLS(a) USAFTAWC(DA). . . . 2(b) USAFTARC(IN). . . . 2(cISFACDL(c) USAFTAWC(DA) . . . 13(e) USAFAGOS(EDA) . . . 1

UNCLASSIFIED

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* UNCLASSIFIED3d . DC i. AAC(1) EADQUARTERS (1) EADQUARTERS(a) O. .. .. .. . ..... (a) LDOC-A.. .. .. .. 1(b) OT. .. .. .......

()(c) XPC. .. .. .. .... j. USAFSO(2II DIVISIONS (1) EADQUARTERS(a 25AD(IN).. .. .. .. 1 (a) HS .. .. .. ..... 1b29AD(DO).. .. .. ...()20AD(IN) . .. .. .. 1 k. PACAF

e. ATC (1) HEADQUARTERS(1) TXPP-X. .. .. ...... 1 (a) DP. .. .. .......U(b) IN. .. .. ...... 1f. AFLC (c) P. .. .. ...... 2(d) CSH .. .. .. ..... 1(1) HEADQUATERS (e) OVD. .. .. ..... 5(a) OX. .. .. ...... 1 (f) C. .. .. ...... 1(g) DM. .. .. ...... 1g. AFSC(2) AIR FORCES(1) EADQUARTERS (a) AF(a) RP. .. .. ...... 1 1. CSH. .. .. .....(b) RLW .. .. .. ..... 1 T.xP .. .. .. ....(c) AMSO(XRW)... .. . ..1 T.DO........I(d) SDA .. .. .. . .... 1 (b) get 8, ASD(DOASD). . 1(e) SH. .. .. ...... 2 (c) AF

(f) LXP .. .. .. ..... 1 1. O.. .. .. .... 1(g) SD(ADJT). .. .. .. 1 2DIP. .. .. .... 1(h) SD(XO). .. .. .... 1 3XP . .. .. ....I i) ADC(EMOTL) .... .. 2 4.DOCT.. .. .. .. 1j) ADTC(CCS). .. .. .. 1 W.DOAC.. .. .. .. 2(k) DTC(SSLT). .. .. ... (d) 3AF(1) SD(YW). .. .. .. .. 1 1. CSH. .. .. .. .. 1Cm) AFATL(DL). .. .. .. 1 7. XP .. . . . 1..(e) '/13AF(CHECO) . . . 1

h.UAS (3) IR DIVISIONS-(1) HEADQUARTERS (a) 313AD(DOI) .. .. .. 1(a) DC. .. .. ...... 1 (b) 14AD(XP). .. .. .. 2(b) HO .. .. .. . .... (c) 27ADU1.DO .. .. .. .... 1(2) UBORDINATE UNITS Z. IN.. .. .. ....(a) ur Scty Rgn(OPD-P) .1 (d) 934AD(DO)... .. .. 2(b) 940 Scty Wg (OOD). 1Iv

U UNCLASSiFIED

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* UNCLASSIFIED1(4)INGS 4. SEPARATE OPERATING AGENCIES(a) TFW(DOEA). .. .. ..... a. ACIC(DOP) .. .. .. .... 2(b) 12TFW(DOIN).. .. .. .. 1 b. AFRES(XP) .. .. .. .... 2U(c)5TFW(DOIN) .. .. .. .. 1 c. AU(d) 6S0W(WHD). .. .. .... 1 1. CSC-SA. .. .. .... 1

(e) 47TFW(DO). .. .. .... 1 T. AUL(SE)-69-108 .. . 2(f) 66TFW(DO). .. .. .... 1 3.ASI (ASD-) ... .. .. 1(g) 88TFW(DO). .. .. .... 1 4.ASI (HOA).. .. .. .. 2(h) 05FW(DOEA).. .. .. ... d. AXFAFC(CEH). .. .. .... 1(1) 32TRW(DOI) .. .. .. .. 1 e. ANALYTIC SERVICES, INC .1I(j) 460TRW(DOI) .. .. .. ...(k) 75TFW(DCO).. .. .. .. 11(1)st Test Sq(A) .. .. .. 1(5) THER UNITS(a) ask Force ALPHA(IN) .. 1(b) 504TASG(DO).. .. .. .. 1

(c) ir Force Advisory Gp. . 1m. USAFEI(1)EADQUARTERS(a) OA. .. .. .. . ..... 1(b) OLO .. .. .. . ..... 1(c) OD. .. .. .. . ..... 1(d) DC. .. .. .. . ..... 1

(2) IR FORCES(a) AF(DO).. .. .. ..... 2(b) 6AF(ODC).. .. .. .... 1I(c)7AF(IN). .. .. ..... 1(3) INGS(a) 36TFW(DCOID). .. .. .. 1(b) OTFW(DOA). .. .. .... 1(c) M6RWDOIN-T) .. .. .. 1(d) 1TRW(DCOI).. .. .. ...(e) 01TFW(DCOI). .. .. .. 1(f) 13TAW(OID).. .. .. .. 1

(4) GROUPS(a) 97RTG(IRCOD). .. .. .. 5

IUNCL ASSIF IED

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* UNCLASSIFIED5. MILITARY DEPARTMENTS, UNIFIED-AND SPECIFIED COMMANDS, AND JOINT STAFFS

a. COMUSJAPAN............. .... .. .. .. .. .. .. ....b. CINCPAC (SAG)................ .. .. .. .. .. .. ....c. CINCPAC (J301)............... .. .. .. .. .. .. ....d. CINCPACFLT (Code 321)...... ... .... .. .. .. .. .. ....e. COMUSKOREA (ATTN: J-3)....... ... .... .. .. .. .. ....f. COMUSMACTHAI............. .... .. .. .. .. . ....g. COMUSMACV (TSCO)................. .. .. .. .. .. .. 1h. COMUSTDC (J3)........................1i. USCINCEUR (ECJB)......................1j. USCINCSO (DCC)................ .. .. .. .. .. ....k. CINCLANT (0021)............ .. .. .. .. .. .. .. ..... 1I1. CHIEF, NAVAL OPERATIONS. .. .. .. ........ ........m. COMM4ANDANT, MARINE CORPS (HQMC)......... .. .. .. .. .. ....n. CINCONAD (CHSV-M). ... 1o. DEPARTMENT OF THE ARMY jTAG6).: IIp. JOINT CHIEFS OF STAFF (J3RR&A). ......... ....... 1q. JSTPS........o .. .. .......... o .. ... 1r. SECRETARY OF DEFENSE (OASD/SA) ......... o.......1Is. CINCSTRIKE (STRJ-3). o.. .... ....... ...........t. CINCAL (HIST).. .. . . . .. . . . . . . . . . . . ...... 1u. MAAG-CHINA/AF Section (MGAF-0) . :o..::o..:. . 1Iv. HQ ALLIED FORCES NORTHERN EUROPE (U.S. DOCUMENTS OFFICE) o . 1w. USMACV (MACJ031). .. .. ..... ......... ......

6. SCHOOLSa. Senior USAF Representative, National War College. .........b. Senior USAF Representative, Armed Forces Staff College .. .. ...3c.enior USAF Rep, Industrial College of the Armed Forces. .. ... 1d. Senior USAF Representative, Naval Amnphibious School.. .... 1e. Senior USAF Rep, U.S. Marine Corps Education Center.......fo Senior USAF Representative, U.S. Naval War College. .. .. ....g. Senior USAF Representative, U.S. Army War College.. .. .. ....h. Senior USAF Rep, U.S. Army C&G Staff College... .. .. .. ....i. Senior USAF Representative, U.S. Army Infantry School. .....Ij. Senior USAF Rep, U.S. Army JFK Center for Special Warfare. . . .1k. Senior USAF Representative, U.S. Army Field Artillery School . .111.enior USAF Representative, U.S. Liaison Office .. ........

7. SPECIALa. The RAND Corporation...... .. .... .. .. .. .. ......Ib. U.S. Air Attache, Vientiane.. .. .. ...... ... .... ...I viii

I UNCLASSIFIED

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TABLE OF CONTENTS* Page

FOREWORD ............................................................ xiCHAPTER I BACKGROUND ........................................... 1CHAPTER II NTRODUCTION OF THE SYSTEM TO SOUTHEAST ASIA ......... 4

Initial Drops ....................................... 6CHAPTER III -- COMMAND, CONTROL, AND EXECUTION ...................... 9CHAPTER IV EQUIPMENT AND OPERATION .............................. 12

The Cambodian Operation ............................. 18FOOTNOTES ........................................................... 19GLOSSARY ............................................................ 22

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FIGURES Follows Page2: JC) Request-execute flow chart for Commando Vault Bomb Drops... 102U) M121 loaded, rigged, and fuzed for drop; M121 extractedfrom C-130 ................................................ 143. (U) arachute triggers extraction process from the C-130aircraft .................................................. 164. (U) arachute-extracted bomb exits the C-130 and commencesdescent ................................................... 165. (U) oving laterally, the bomb nears the ground ............... 166. (U) ense jungle canopy at desired point of impact ............ 16

17. (U) Fireball of the BLU-82B bomb .............................. 168. (U) econds after the explosion ...................... ...... 169. (U) ushroom cloud rises over the impact point ............... 16--. (U) Presto! A good one-ship landing zone! .................... 16

Ix

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FOREWORDAttempts to create helicopter landing zones through the use of tac-

tical strikes were made as early at October 1966 in the eastern II CorpsTactical Zone (CTZ) under Operation Irving, only to meet with a conspic-uous lack of success. As a forward air controller (FAC) reported afterone such operation:

"Finally, toward the end of the day, we had four connect-ing craters out of at least 20 attempted bombs, but thefinal evaluation by the ground connander was that,although we had cleared the area, the terrain was too muchof a slope or too rough to use as an LZ anyway; so therewas a waste of about four sorties." 2/

Another FAC in the same operation ruefully recalled that. . after expending five flights of fighters, we stilldidn't have an LZ that you could land a chopper in..In many cases we expended a great deal of ordnance in anarea and never actually constructed an N."

The general opinion of the FACs and air liaison officers (ALOs) afterthe over-all operation was that the use of a tactical air effort to con-struct LZs for the Army was "quite a waste of tactical airpower." Evenafter sufficient strikes had been put in o clear the area, the resultingcraters usually made the landing zone unsuitable for helicopter operations.

This report follows the evolution of a different concept: that ofdropping a "big" bomb from a transport type aircraft to create "instant"helicopter landing zones in Southeast Asia (SEA)--from inception, throughdevelopment and testing, to eventual adoption as a standard, highly suc-cessful operational tactic which would stand as an exemplar of inter-service cooperation.

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CHAPTER IBACKGROUND

on 20 November 1967, the Military Assistance Command, Vietnam (MACV)Scientific Adviser Office requested assistance from the SEA Mobile Explo-sive Ordnance Disposal (EOD) team at Tan Son Nhut AB, RVN, in helping todesign a method for explosively clearing helicopter landing zones inheavy jungle terrain. Under a project later to be known as Combat Trap/Commando Vault, it was decided to try the M118 3,000-lb. demolitionbomb for this purpose. On 9 December 1967 the bomb, together with thenecessary equipment, was flown to Dak To, in northwestern II Corps, andplaced nose-down on a wooden rack 20 inches above the ground. Later inthe day, an Army CH-47 helicopter airlifted the platform and lowered it

he selected site in heavy jungle near Dak To, while EOD personnelset up booby traps at distances of 10, 50, 100, and 150 feet from thebomb. On 10 December 1967, when the EOD team detonated the weapon, thejungle was cleared for an area about 150 feet wide, and all booby traps4/were either detonated or disabled by the blast.

As a result of this helicopter landing zone evaluation, MACV directedSeventh Air Force (7AF) to develop the capability of delivering specializedordnance for clearing such heavily-jungled areas. Use of the Ml fuzeextender on Mk 84 and M118 bombs gave 7AF a partial capability in this5/direction.

The Armament Development and Test Center at Eglin AFB, Florida, alsoconducted tests between 29 April and 31 July 1968 to obtain tree-clearingI1

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data on the blast effects of 1,000-lb. samples of two different explosives--* 6/DBA-22L and Astrolite A-1-5--using Tritonal as a base comparison.The explosives were loaded into BLU-lB/B (fire bomb) casings to minimizefragmentation effect, then statically detonated in a forested area toi7/work up peak overpressure and effects data.

Each test site consisted of a 150-foot-diameter circle of trees,similar inensity, size, and type to those which might be encountered inSoutheast Asia. At the center of each test site were four or more largetrees, at least one of which had to be over 18 inches in diameter andlocated within 15 feet of target center. Fifteen detonations, withvarious combinations of fuzing and height of the bomb above the ground,yielded pressure data and gave a rough indication of tree-clearing8/capability.

Under the conditions of the tests, it was found that 1,000-lb. bombscontaining any of the three types of explosives failed to clear a forest-- 9/area suitable for helicopter landing operations. Thus, it becameobvious that, if "instant" helicopter landing zones were to be constructedin forest or jungle of any real density, far heavier munitions (evenheavier than the Mk 84 and M118 bombs already tested in South Vietnam)would have to be employed. Simultaneously, the U.S. Army began tests ofthe M121 10,000-lb. bomb at Fort Benning, Georgia. This monster, instorage since the retirement of the B-36 bomber, was statically detonated

*Tritonal was composed of 80 per cent TNT and 20 per cent powderedaluminum.

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inwooded artillery range. While the results were satisfactory,practical considerations demanded aerial delivery for any employment inSoutheast Asia. As a result, the M121 was modified and redesigned tocontain two independent fuzing systems, one forward and one aft, as wellas a stabilization parachute. Continued testing with inert bombs onwestern test ranges, using both the Army's CH-54 "Flying Crane" helicopterand the Air Forcets C-130, demonstrated the feasibility of using thelatter as a "bomber," but eventually resulted in a decision to abandon10/further employment of the big helicopter in this role.

In December 1968, the 834th Air Division, headquartered at Tan SonNhut Air Base, RVN, conducted a ten-weapon operational test of the M121

11/in South Vietnam, again under the code name Combat Trap. From theseinchoate experiments eventually evolved the operational concept called

ault, which was subsequently to be tested and evaluated, thenemployed regularly in Southeast Asia.

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CHAPTER IIINTRODUCTION OF THE SYSTEM TO SOUTHEAST ASIA

COMUSMACV's original request had stated that the desideratum wasfor landing zones of five-helicopter size and that development effortsshould be concentrated on the largest weapon compatible with C-130delivery. In the dense jungle environment normally encountered inSoutheast Asia, even the largest weapon then in the inventory--the10,000-lb. M121--was inadequate to this demand. Experience showed that

when target selection criteria were closely adhered to (i.e., basicallylevel terrain and within MSQ-77/TPQ-1O radar accuracy parameters), theM121 would effectively clear a one or two-ship landing zone a little

13 /0 per cent of the time.

A series of messages between November 1968 and February 1969 dis-cussed the question of what munition to use. Should new weapons bedeveloped, production be resumed on old ones, "super heavy" (25,000 to35,000-lb.) bombs be considered, or new, more powerful high explosives beadapted for use with smaller casings? All of these alternatives wereweighed and pondered. The inventory of Ml21s was extremely low, andthe Office of the Air Force Chief of Staff (CSAF) favored resumption ofproduction of the weapon. In response to this high-level preference, theAir Force Weapons Laboratory, Special Applications Branch at KirtlandAFB, Albuquerque, New Mexico, devoted its early efforts to adapting theM121 bomb to the new role.

Since the quantity of existing Ml21s was so limited as to offerlittle future practical employment, unless their manufacture were resumed,

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ir Force Weapons Laboratory's Special Applications Branch concludedthat it ight be advantageous to try a new explosive, DBA-22M, which hadbeen developed for Sandia Laboratories, and load it into a larger bombcasing. As a result, in early December 1968 the Air Force requestedSandia, through the Albuquerque Operations Office of the Atomic EnergyCommission, to design and develop a possible follow-on bomb to the M121,weighing 15,000 pounds and filled with the gelled-slurry explosive DBA-22M.The resulting design and development program lasted approximately oneyear, winding up in the autumn of 1969. With the development programcompleted, the Air Force requested the Albuquerque Operations Office ofthe AEC to undertake, through Sandia Laboratories, the fabrication of225 emergency-capability 15,000-lb, BLU-82/B bombs. Simultaneously, pro-gram management was transferred from the Special Applications Branch atKirkland AFB to the Armament Development and Test Center at Eglin AFB,Florida.

During this period, tests of a 15,000-lb. gelled-slurry, explosive-filled bomb were being conducted at Tonopah Test Range, Nevadi, in con-nection with the Cloudmaker Program. This was followed by the first live,full-scale test drop of a BLU-82/B at the Tonopah Test Range on 1 April1969, the rigging of the bomb and its cradle to the Air Force aerialdelivery platform having been performed at El Centro Naval Air Facility(NAF), California. The rigged bomb was loaded on a C-130 aircraft andthe drop staged out of Hill AFB, Utah. The bomb impacted on one of thelarge dry lake bed targets at the Tonopah Range. Informed of this test,

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Seventh Air Force recommended that any decision on whether or not to pro-duce the M121 be delayed until the results of the Nevada desert dropcould be evaluated.

In ts protest against resumption of M121 production, 7AF argued as17/foll1ows:"The 15, 000-lb. liquid-filled device currently undergoingtesting -at Tonopah appears attractive from several aspects.The binary liquid explosive can be shipped and stored in itstwo component parts, which are non-explosive when not combined.The advantage of storing non-explosive items rather thanlarger explosive packages should not be overlooked. Further,in view of the requirement for even larger HLZ (helicopterlanding zone) construction devices, it appears that theliquid explosive system offers a great deal of flexibilityand growth potential."

Initial DropsThe results of the Nevada tests showed that the larger weapon had

significantly greater blast effect and peak overpressure than the M121,but, pending comparison drops between the two in the SEA area, the M121was given its first tactical employment in support of Operation TaylorCommon in I Corps Tactical Zone. Under TPQ-1O (a Marine radar systemcomparable to the USAF's MSQ-77) guidance, ten of the 10,000-lb. bombswere dropped between 12 and 20 December 1968. The average miss distancefrom the desired point of impact was 103 meters, although it should benoted that the greatest miss distances occurred on the first four drops,18/when all concerned were still in the learning stage. These were termedtraining and test drops for the system; therefore, LZ size and suitability19/were not recorded.

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Following the initial drops, the use of the Ml21 as an HLZ clearingdevice became standard procedure, with requests for its use totallingmore than 20 per month. The long-awaited opportunity to compare the effectsof the 10,000 and 15,000-lb. devices came in the spring of 1969, whenthe first of the experimental 15,000-lb. CD-Is arrived in SEA. The CD-i(its production nomenclature was later changed to BLU-82/B) was virtuallyhandmade, but nevertheless (or, perhaps, because of this fact) functionedperfectly. On 11 May 1969, two CD-Is and two Ml21s were dropped, to per-mit a comparison of the two weapons. The findings of the evaluation wereas follows:

Handling and loading of the CD-I were virtually identical tothose of the MZ2%l with the exception of the requirement forcovered storage. Release and retardation were virtuallyidentical to those of th e M121. Release and retardationsystems for both of the test CD-Is operated without mal-function or incident. Delivery accuracy was consistentwith current Mi2i drops using MSQ radar.Evaluation of the relative effectiveness was by II FieldForce personnel and by photographic analyses. Although theCD-i did not produce the required five-helicopter zone, itproduced a cleared area approximately two-and-one-halftimes th e area created by the M21. Both weapons leftsome residual stumps of varying size.

Even though the CD-I did not satisfy the requirements of the SEAOR168 for a five-helicopter zone--the figure "five" as an ideal had infact been snatched out of thin air at random, rather than being the productof meticulous estimates and careful calculations--the results wereimpressive enough to prompt the Commander, Seventh Air Force, to press foruse of the CD-I in lieu of revived production of the M121. Of additional

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importance in this decision was the fact that the 15,000-lb. productionversion of the BLU-82/B could be in the theater by early 1970, while thelead time for resuming production of the M121 was placed at 15 months. 2/

Even so, it was decided to continue the use of the M121 until thebombs in inventory were exhausted, even after the BLU-82/Bs began arrivinginietnam inebruary 1970. The first drop of the production models tookplace on 23 March; "thereafter, delivery was carried out as a matter ofcourse. Either of the bombs might be employed at a given location,the choice being dependent upon many variables, such as inventory avail-ability or the nature of the target. As of 1 October 1970, 323 bombs hadbeen used for HLZs and fire base construction, 216 of them being Ml21sand 107 BLU-82s. With the dropping of the last M121 on 8 August 1970,the inventory of that munition was exhausted.

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CHAPTER IIICOMMAND, CONTROL, AND EXECUTION

A tortuous chain of command, control, and execution was involved inthe use of the heavy bombs for helicopter landing zone construction.Since the field commander would be the ultimate user of the zone, it ashe who initiated the request, through channels, to MACV. (See FlowChart, Figure 1.) The Army (or Marines, as the case might be) then per-formed the targeting, while MACV controlled the bombs, since these itemswere a definitely limited resource. Headquarters, 7AF, was responsiveto MACV direction, and, upon receiving approval for a delivery, directedthe 834th Air Division to conduct the drop operation.-

All bombs, both M121 and BLU-82/B, were stored at Cam Ranh Bay, andit as there that the operational aspect of the deliveries originated.Detachment 2 of the 834th Air Division was located at Cam Ranh Bay, fromwhich base itrovided the over-all management function. Making up a partof Detachment 2 were both C-130B aircraft and personnel TDY from the 463rdTactical Airlift Wing at Clark AB, Republic of the Philippines, whichcame under the operational control of the 834th Air Division while theywere at Cam Ranh Bay. These crews received ground and airborne trainingin Commando Vault loading, handling, communications, and delivery tech-26/niques prior to their arrival in-country. While actual loading of thebombs into the C-130Bs was accomplished by the 14th Aerial Port S uadron,Qnce aboard-the aircraft, themun.itions were rigged for 4rop.by personnel

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i 27/of Detachment 2, and fuzed by ordnance specialists. The Herculesitself required no modification other than temporary installation of anX-band radar transponder beacon to aid the MSQ site in precision-tracking

8/it.In view of the recognized destructive power of the bomb, intricate

and detailed coordination among all action agencies was necessary toavoid the possibility of a short round. These agencies included theground commander involved, the appropriate Direct Air Support Center

(DASC), the Strike Plans Branch of the Tactical Air Control Center, 834th29/Operations, and the radar site which was to direct the drop. Doubleand triple checks were made, in the interests of safety to non-combatantsand friendly military forces, before one of the bombs was actuallyreleased. Among the many procedures which followed the issuance of anexecution order were the following:

* The FAC assigned to the ground unit reviewed in detail thespecific coordinates and features of the desired zone withthe ground commander. 834th Air Division assigned a Combat Operations Mission Coordi-nator to stage at the forward location and fly with the FAC;

he also verified coordinates, the requested TOT, and terrainfeatures for target suitability. The frag tape printout was proofread and checked for accuracyby the TACPS Staff Operations Officer and the Chief of StrikePlans before the message was released.

The target was defined by eight-figure Universal TransverseMercator coordinates, both in figures and spelled out. Sucha message might, for example, define the target as "YankeeTango One Three Six Five Zero Five Eight Nine (YT 13650589)."This placed the DPI (desired point of impact) within a ten-meter square.

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mFigure 1

(C) Request-execute flow chart for Commando Vault Bomb Drops.

FIELD COMMANDERBATTALION/COMPANYDIVISION

FIELD

MACV TASE (Approval Request) I ACJ 3- MACV TASEf (Approval Message)

7AF TACPS Frags Control

L_- 834th AIR DIV Frags FlightIDet 2, 34 AD

f14th Aerial Port Sq MSQ Site

Execute Execute

I9

Command/Control ChannelsCoordination and WarningRadar Tracking and Communication

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If any of the agencies involved--TASE (Tactical Air SupportElement--the Army coordination element collocated with 7AFTACC), TACPS, 834th Air Division, the MSQ site, or the fieldcommander--detected any discrepancies regarding target location,time over target, run-in heading, or anything else that mightendanger friendlies, clarification or amendment was immed-iately requested.

Early in the program, as much as six days' lead time was requiredby the field commander before he could expect a Commando Vault-createdlanding zone; however, continued efforts by 7AF TACC and streamlining ofprocedures through experience reduced this lead time to as little asthree days. From the time the request was received by the TASE and anapproval message returned by MACV J-3, the 834th Air Division required48 hours for the drop. When the aircraft and crews were alreadyin-country, this requirement could be dropped to 24 hours, provided theneed were urgent.

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CHAPTER IVEQUIPMENT AND OPERATION

A description of the two heavy bombs used in Commando Vault pro-vides a rough comparison of their respective destructive powers. TheMl21 was approximately 9-1/2 feet long, nearly four feet in diameter,and weighed 10,800 pounds, of which 8,050 pounds comprised the explosiveagent, Tritonal. The BLU-82/B measured out at 11-1/2 feet in length,without fuze extender, and 4-1/2 feet in width. Its filled weight was15,000 pounds, the explosive agent being 12,600 pounds of ammonium-nitrate powdered-aluminum slurry called DBA-22M* It ad been intendedinitially that the two components would be shipped separately to CamRanh Bay, where they would be mixed and the containers filled. However,the difficulties of adequately training personnel on the job within the12 months of service in Vietnam before rotation dictated that the con-tainers be filled at the factory and shipped to Cam Ranh Bay separatelyfrom the fuzes and booster charges. 32/

*DBA-22M was a powerful explosive made up, in part, of particulatealuminum, ammonium nitrate, water, thickeners, and stabilizers--though a detailed chemical analysis was proprietary information,solely known to the manufacturer and supplier, IRECO Chemicals, of SaltLake City, Utah. Curiously enough, Air Force interest in DBA-22M hadoriginated in Sandia Laboratories' need for a conventional high explo-sive that could be used in a test device capable of producing a simu-lated nuclear cloud for the exercise of RB-57 sampler aircraft underProject Cloudmaker. This device, incidentally, was to weigh 45,000pounds! (By way of comparison, the largest World War II omb hadweighed 23,000 pounds.)

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The weapons were loaded by crane and muscle into cradles on palletsat Cam Ranh Bay, then subsequently put aboard the C-130, where they under-went final rigging and fuzing. (Figure 2.) The complex fuzing systemconsisted of an M904E2 fuze, an MlAl fuze extender (a three-foot charge-filled rod on the nose), two BBU-23/B fuze boosters, a T45E7 or M148 noseadapter booster, a T46E4 or M147 tail adapter booster, two M9 non-delayfuze delay elements, a fuze drive assembly, and various arming wires,guides, clips, and other assorted items. The purpose of the fuze ex-tender was to cause detonation above the ground, creating greater out-

ward blast effect and lessening the chance of deep cratering, whichwould defeat the purpose of the landing zone. In addition, an M905 fuze33/inhe tail provided back-up for the primary system in the nose.

Two Ml21s could be loaded aboard the aircraft and dropped on sepa-rate runs. If ne bomb created a satisfactory LZ, the C-130 could returnto base with the other bomb still aboard; or, if the landing zone was notconsidered adequate, the pilot could bring the aircraft back for anotherrun to enlarge the zone. In one instance, an M121 was dropped, creatinga good one-ship zone. The aircraft came around for another drop, andthe MSQ operator told the crew they would lay the second one 30 metersfrom the first. As it turned out, the bomb actually hit 41 meters from

34/the first.

Although the cargo compartment of the C-130 was large enough for twoBLU-82/B bombs, only one was carried, inasmuch as center of gravitycharacteristics of the Hercules would render a safe landing impossible,should circumstances require a return to base with one bomb of a two-bombm 35/load still aboard.5 13 l ia

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S

Following departure from Cam Ranh Bay, the Commando Vault aircraftproceeded to the target area, where it orked directly with the DASC(Direct Air Support Center), the MSQ-77 precision radar controller, andthe FAC, accompanied by an 834th Combat Operations Mission Coordinator.Any of these could cancel the drop, as could the ground commander, fora variety of reasons. Coordination had already been arranged betweenthe 834th Air Division and the MSQ site to ascertain that the targetarea was not masked from the radar and that radar "up" time was avail-able (many times TOTs had to be adjusted because the radar was preemptedfor Arc Light or other planned missions); so cancellation for thesereasons was rare. However, if the ground commander, FAC, or 834th coord-inator determined that the terrain was unsuitable, if weather precludedthe FAC or coordinator from seeing the target, or if friendlies werewithin 1,500 meters of the desired point of impact, the mission would becancelled. Fifteen hundred meters was the minimum distance from DPI forany non-combatants or friendly forces, but it as highly recommendedthat any troops intending to use the zone be 3,000 meters from the36/impact point, owing to the psychological effect of the blast.

When the FAC gave instructions to proceed, the radar controllervectored the aircraft through one or more practice runs, usually at

or 7,000 feet above ground level (although some drops were made up37/

to 13,000 feet), before the final run. When procedures were consid-xact, the aircraft made the drop under precise radar control.

The controller took into consideration the ballistics characteristics ofthe weapon, wind forecasts as supplied by the 1st Weather Group, and

ltitude of the drop aircraft, and these were all run through the

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UNCLASSIFIED

I M-121 loaded, riq~qed. and fuzed for dropi

MI n xrctdfo icatFIURIUNLSSFE

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38 /radar computer prior to drop.L

"

With the palletized bomb ready, the following sequence of eventswent into effect: 39/

.Six minutes before bomb release, the loadmaster released the left-hand cargo lock. This left only the right-hand lock holding thepallet on the rails.At 30 seconds before release the co-pilot remotely streamed theextraction-chute behind the opened ramp.As the radar controller counted down the final seconds with a5, 4, 3, 2, 1 count, the loadmaster prepared and, on the command,"Mark," released the right-hand locks.A knife on the static line severed the webbing that secured thebomb to the cradle and platform as the bomb cleared the ramp.Lanyards attached to the left-hand nose collar clevis and to theparachute deployment bag in turn initiated arming of the noseand tail fuzes respectively, as the 24-foot slotted chute whichstabilized the bomb deployed from the aircraft and pulled thebomb from its wooden cradle. A brush deflector on the Ml fuzeextender enabled the bomb to pierce the jungle canopy beforeexploding three feet above the ground.

With 6,000 feet AGL the normal drop altitude and at 150 knots trueairspeed, the average time from release to impact was approximately 26seconds. This placed the aircraft a little more than a mile from theblast. The explosion could be heard inside the aircraft, and the shockwave felt, but overpressure had attenuated at that distance to such an40/extent that it as barely noticeable.- (Photographs of the dropsequence, Figures 3-10, depict the operation.)

At ground zero, however, the blast was devastating. The M121 clearedan area approximately 60 meters in diameter. The BLU-82/B extended that

* 15i

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CONFIDENTIALto about 80 meters. In the case of the M121, this meant the creation ofa "cleared" area of roughly 2,800 square meters; while the BLU-82/B~41/increased the affected terrain to over 5,000 square meters. Flashfrom the explosion burned foliage off trees and brush out to aboutdouble the radius of the usable zone proper. To use the term "cleared"is, owever, not strictly accurate, as can be seen from the photographs:numerous stumps invariably remained standing. However, it as also truethat the blast generated overpressure sufficient to uproot trees threefeet in diameter near the point of impact, and continued outward farenough that Viet Cong found as far as 600 meters from.ground zero 42/remained shocked and dazed as long as 18 hours after the explosion.

Although the explosive force did not fully satisfy the SEAORrequirements, several spinoff benefits accrued to help make the project

successful one. Employed over proper terrain, Commando Vault provided

at the least a one-ship landing zone; and, almost as often, it created atwo-ship clearing. The first helicopter or helicopters into the zonecarried security troops to set up a defensive perimeter. These men wereassured of two vital conditions: One, the area immediately in or aroundthe zone would be completely cleared of booby traps and punji--theneedle-sharp bamboo sticks implanted in the ground to inflict foot andleg injuries upon friendly forces. Two, there would normally be noeffective enemy forces within half a kilometer of the drop zone, blastpressure having incapacitated them, and the psychological effect uponthose who might otherwise be effective was shattering. The proof of

I 16CONFIDENTIAL

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to

S-4-

4-x ((v4-

WS. U

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4J

AV 4-)

x _40J.1>4 .1UN 0)0Armis4st~ jC)

j

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4-

to 4-OS- (4J

C S.-2

0G)0

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ofA

:4jlP

impact

FIGREUNLSSFE

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Ua ~LL C"iWC4LL.

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AAa)c4-

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44

41t

ir It

ILl

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these physical and psychological effects was that assault forces enter-43/ing the HLZs immediately after the blasts were usually unopposed.

Once the security forces were in, engineers followed immediately,bringing inhain saws, shovels, and bulldozers to enlarge the LZ to onecapable of receiving five or six helicopters.

Not counting .the M121 drops, the results of 107 BLU-82/B missionsshowed the following:

ones 17* One-ship zones 44Two-ship zones 36Three-ship zones 8Four-ship zones 2

Since many of the unsuitable zones were rendered so by unfavorableterrain features (for example, those bombs which were dropped on a ridge-line) or by lack of knowledge of the actual surface features concealedunder the heavy jungle canopy--including large boulders and the like, thedegree of success achieved by the Commando Vault drops appears remarkable--

ore so if one recalls that the landing zones were completed withinminutes or hours, as contrasted with the minimum of several daysrequired when they had to be constructed by standard engineering methods.

Of the total attempted HLZs, 15.88 per cent were not suitable,84.12 per cent could accommodate one or more helicopters immediately, and33.64 per cent were capable of immediately accepting two aircraft. Theaverage miss distance of the drops executed by the MSQ-77/834th Air Divi-sion combination--considering both M121 and BLU-82/B bombs--was 58 meters.

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A laudable 62.8 per cent fell within 50 meters, and 95.2 per cent camewithin 250 meters--a proximity more than adequate for most groundn 45/operations.

The Cambodian OperationAt the request of the Lon Nol government in Cambodia, Commando Vault

operations were conducted in the struggle for that country following thef Prince Norodom Sihanouk. The first BLU-82/B was dropped there

at XU 55200120 (UTM coordinates) in the southeastern portion of thecountry, not far from the RVN border, on 1 May 1970, and before the U.S.forces pulled out, 15 more BLU-82s were dropped. In addition, fourMl21s, among the last in he inventory, were released in June. Theselater created three usuable landing zones--two of them two-ship zones.The fourth bomb dudded when it did not separate from the cradle. Of theBLU-82Bs, 13 of the 16 made suitable zones: eight one-ship, four two-ship, and one three-ship. The three which did not create usable LZs

anded on steep slopes or left too many stumps for helicoptersto maneuver between.

All in all, the Commando Vault program proved a workable, highlyeconomic method of accomplishing what had hitherto been a time-consuming,dangerous, laborious, and costly task. In creating "instant HLZs" forthe ground forces, Commando Vault reaffirmed the flexibility of modernair power.

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UNCLASSIFIED16. (U) bid., p. 44.17. (S) sg, Hq 7AF to CINCPACAF, Subj: SEAOR 168, 170755Z Mar 1969.18. (C) iscussions with Lt Colonel Donald K. Cole, 834th Air DivisionOperations, 6 Oct 1970. Also, (C) 34th Air Div Commando_ Vault Log.19. (C) ommando Vault Log.20. (S) arrative Chronology, 7AF DCS/Plans-Requirements Directorate

Input to 7AF History, Apr-Jun 1969. (Extracted material (C))21. Ibid.22. (S) arrative Chronology, 7AF DCS/Plans-Requirements DirectorateInput to 7AF History, Apr-Jun 1969. (Extracted material (C))(S) sg, Hq 7AF to CINCPACAF, Subj: SEAOR 168, 170755Z Mar 1969.23. (C) ommando Vault Log.24. Ibid.25. (C) iscussions with Lt Colonel Donald K. Cole and Lt Colonel GeraldR. Lane, 834th Air Division Operations. Hereafter cited as

Discussions with Lt Colonels Cole and Lane. Also, (U) 34thCommando Vault Briefing.26. Ibid.27. Ibid.28. Ibid.29. (C) AF Form 4, Subj: Investigation of TACP Frag Procedures, 10Jan 1970.30. (C) AF Form 4, Subj: Investigation of TACP Frag Procedures, 10

Jan 1970.(C) iscussions with Captain Gordon L. Boozer, Operations StaffOfficer, 7AF TACPS, and (C) iscussions with Major Roger U.Obermeier, USA, Operations Staff Officer, TASE (MACV J3-071).31. (C) iscussions with Lt Colonels Cole and Lane.32. (U) echnical Data from 834th Air Division.(C) iscussions with Lt Colonels Cole and Lane.33. (C) iscussions with Lt Colonels Cole and Lane.

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UNCLASSIFIED

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UNCLASSIFIEDI 34. (C) bid.U Tn-erview with SMSgt George E. France, 600th Photo Sq, 3 Jun1970. Hereafter cited as Interview with SMSgt France.

35. (C) Discussions with Lt Colonels Cole and Lane.36. (C) bid.37. (C) 34th Air Division Comando Vault Logs.(U)34th Air Division Comando Vault Briefing.38. (C) iscussions with Lt Colonels Cole and Lane.39. (U) 34th Air Division Comando Vault Briefing.40. (C) Discussions with Lt Colonels Cole and Lane.41. (C) Ballistics Tables for BLU-82/B Bomb.U 834th Air Division Comando Vault Briefing.42. (C) nterview with SMSgt France.43. (C) Discussions with Lt Colonels Cole and Lane.44. (C) 34th Air Division Comando Vault Logs.45. (C) bid.(C) -scussions with Lt Colonels Cole and Lane.46. (C) 34th Comando Vault Logs.

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GLOSSARY

AGL Above Ground LevelBLU-82/B 15,000-pound bombCTZ Corps Tactical ZoneDASC Direct Air Support CenterDPI Desired Point of ImpactEOD Explosive Ordnance DisposalFrag Portion of overall order directing mission accomplishmentFSB Fire Support BaseHLZ Helicopter Landing ZoneLZ Landing ZoneMACV Military Assistance Command, VietnamMSQ-77 Highly accurate ground-based Army radarM-121 10,000-pound GP bombPI Point of ImpactSEAOR Southeast Asia Operational RequirementTACC Tactical Air Control CenterTASE Tactical Air Support Element (U.S. Army)TOT Time over TargetTPQ-1O Marine radar system, similar to MSQ-77TT TeletypeUTM Universal Transverse Mercator (Grid coordinate system)