Phou Pha Thi (Site 85) 15 Miles from NV border, 120 Miles from Hanoi
Photo courtesy of Lt/Col Jeannie Schiff USAF (ret)

202642N 1034305E (UH65496355)
Phou Pha Thi, Laos

In the later half of 1966, the idea was conceived to install a Radar Bombing Control System (MSQ-77) at TACAN Channel 97 (Site 85) in Laos. The MSQ-77 is a sophisticated piece of electronic equipment to direct air strikes without the pilot actually seeing his target. The advantages being 1) that the aircraft can fly at an altitude reachable only by Surface to Air Missiles (SAM) and 2) bombing can be accomplished in all types of weather day or night. The advantages were obvious, but the political obstacles were going to be difficult. Laos was a neutral country. Placing this equipment in northern Laos would imply that Laos was allowing another country to use their country to mount an attack on a neighbor, which had recognized their neutrality. But this neighboring country, North Vietnam, was using their soil to transport men, equipment and supplies through the Laos panhandle into Cambodia and South Vietnam (Ho Chi Min Trail).

March 11, 1968, Site 85 was overrun by PAVN commandos.Eleven of the nineteen brave men on Phou Pha Thi (site85) were KIA/BNR or POW/MIA, no bodies or remains have ever been found. This was the largest single ground combat loss of USAF personnel during the Vietnam war.

A series of Telegrams and Memorandums are used to develop the story of the unnecessary Tragedy at Site 85.

Below is a telegram from CINCPAC to the Chairman JCS. Dated February 25, 1967.

278. Telegram From the Commander in Chief, Pacific (Sharp) to the Chairman of the Joint Chiefs of Staff (Wheeler)/1/
Honolulu, February 25, 1967, 0152Z.
/1/Source: Center of Military History, Westmoreland Papers, Message Files, COMUSMACV, 1 Jan-31 Mar 1967. Top Secret. Repeated to Westmoreland and General John D. Ryan, Commander in Chief, Pacific Air Force.
250152Z. Installation of MSQ 77 in northern Laos (S). A. CINCPAC 282347Z Nov 66 (Genser). B. OUSAIRA Vientiane AIRA/EMB 01834/291055Z Nov 66 (Genser)./2/
/2/Neither reference has been found, but they are summarized in the text below.

1. A front channel message which I have just released provides the military rationale and the necessity of installing an MSQ-77 at Site 85 in Laos.

2. In November CINCPACAF requested authorization to develop a concept and plan for installation of an MSQ-77 in northern Laos and authorization to discuss this matter with Ambassador Sullivan. Ref A authorized CINCPACAF to proceed with plans as requested and directed that AmEmb Vientiane be provided with detailed requirements. Ref A further urged the Ambassador's concurrence in this proposal and assistance in selection of a suitable site. Ref B stated that Ambassador Sullivan's view of installation of MSQ on Lao territory was decidedly negative, but would authorize his representatives to discuss proposal with PACAF representatives. He further doubted that RLG would be willing to accept such a major installation for which they would consequently feel security obligations beyond their means.

3. In early December Gen Harris/3/ sent a message to Ambassador Sullivan stating that due to the urgency of this proposal and potential impact on the success of our air operations in RT and BR he welcomed the opportunity to provide a briefing to him at Udorn on 10 December 1966. His response again restated his grave doubts that RLG would be willing to permit installation of MSQ-77 in Lao territory and that he had even graver doubts that Washington would even authorize him to propose such an installation to the RLG. Nevertheless, the Ambassador agreed to meet PACAF representatives at Udorn and attend briefing.
/3/General Hunter Harris, then the Commander of the Pacific Air Force.

4. At the briefing Ambassador expressed keen interest in the tactical merits of an MSQ in northern Laos but again stated that he had misgivings about its political acceptability. He expressed concern that the RLG would most likely term such an installation as an indication that they would in fact be proving direct support to offensive operations against NVN rather than maintaining a neutral position and taking defensive action only. No commitment was made by Ambassador that he would provide further support to this proposal.

5. I discussed the subject with him during his visit en route to Washington. He again emphasized his previous views. It appears that he did not intend to give his full support to this proposal at State level. Due to the significant increase in air operations capability which this MSQ will provide, I believe we must attempt to obtain approval.

6. The information contained in my Genser message is a condensed version of PACAF briefing and plan for implementation. It has been concluded that we can support this plan. I understand that HQ USAF has already taken action to repackage MSQ-77 equipment for this type development and if not used as proposed, it will still be valuable for contingency purposes. If go ahead is received, we can have this MSQ in operation in 30-45 days.

7. In summary, from a military viewpoint an MSQ located in northern Laos would greatly enhance our air campaign against the enemy. This is no cure-all by any means, but we must do more now to increase the effectiveness of our air operations in the northern area. The Ambassador's original objection was based on doubts about the security of site which we have overcome to some degree as expressed in other message. However, his later objections, which shifted to the political angle, may or may not be completely valid. This is something that will have to be flushed out at other levels.

The dialog continued and plans were being developed. Then on May 1, 1967 the following memorandum from the Laotian Ambassador (Sullivan) was sent to the Assistant Secretary of State for East Asian and Pacific Affairs (Bundy).

283. Memorandum From the Ambassador to Laos (Sullivan) to the Assistant Secretary of State for East Asian and Pacific Affairs (Bundy)/1/

Washington, May 1, 1967.
/1/Source: Library of Congress Manuscript Division, Harriman Papers, Kennedy and Johnson Administrations, Far East, General. Top Secret.
Limitations on Military Actions in Laos
1. You asked me to set out in a paper my estimate of the limitations which face us with respect to extending military actions, both ground and air, in Laos. I will list by subheading those various items which have been proposed or contemplated, and give you my current best judgment with respect to each.

3. Air Action

A. Overflights. Despite the Soviet protest and the probable ICC action on US overflights of Laos, I think Souvanna will hold the line and permit these to continue. The one exception to this would be B-52 overflights. For some reason which is hard to define (perhaps the nuclear capability) overflights by B-52's carry much more propaganda wallop than overflights by fighter bombers. The political and propaganda repercussions of such overflights are in my judgment far greater than the limited marginal operational gain. In short, the 20 minutes to an hour which we would save by overflying Laos rather than going south of Cambodia are just not worth the consequences. Therefore, I believe we should hold the line in running our B-52's from Utapao south of Cambodia.
The B-52's which come from Guam will continue to execute the bulk of the raids in Laos in any event. I am not convinced that there is such a crying need for flexibility that we must change this pattern. Consequently, we must avoid public acknowledgment of B-52 activity in Laos and we must guarantee no slippage by preventing B-52 overflights from Utapao.

B. Air Seeding. As I indicated above, air seeding can be done provided we characterize it as a continuing part of our interdiction campaign and don't label it a barrier. As a matter of fact we have already done some air seeding in Laos and I have Souvanna's concurrence in it. Therefore, if we handle this one correctly it presents no problems. If we get the issues all tangled up with barriers it could cause many great difficulties in attempting to obtain Souvanna's concurrence.

C. MSQ-77. Air Forces wishes to install MSQ-77 at site 85. I am having further discussions with Air Force Secretary Brown and Chief of Staff McConnell today. In general, I think Souvanna would reject this if it were put to him honestly. He has agreed to the installation of the navigational devices in Laos and we have installed TACAN's on Lao soil. However, the TACAN is a passive device. The MSQ-77 is a command radar which takes positive control of air strikes in North Vietnamese territory. Moreover, it involves several buildings and about 40 men. It would be very conspicuous. I wonder if it is worth it.

Site 85's location in northern Laos was roughly 120 Miles from Hanoi, or the distance between San Diego and Los Angeles, CA. The existence and location of Site 85 was declassified in 1983.


A little over a month later, June 3, 1967, a Telegram was received at the Embassy in Laos from The Department of State. It looked like the political problems could be worked out to everyone's satisfaction.

290. Telegram From the Department of State to the Embassy in Laos/1/

Washington, June 3, 1967, 12:15 a.m.
/1/Source: Department of State, Central Files, DEF 15 LAOS-US. Top Secret; Priority; Exdis. Drafted by Hamilton; cleared by Aldrich, Habib, and Steadman; and approved by Kohler. Repeated to JCS, CINCPAC, and COMUSMACV.
207815. Subject: MSQ-77. For Ambassador from Kohler.

1. We have carefully reviewed JCS request for MSQ-77 installation at Phu Thi (Site 85),/2/ in light your judgment of political risks and liabilities for us and Souvanna, expressed in previous correspondence and during your consultations, and of renewed DOD affirmation of need and urgency to achieve maximum effectiveness in air operations over North Vietnam.
/2/As reported in telegram 194052 to Vientiane, May 13. (Ibid., POL 27 LAOS)
2. Unless you perceive new factors not previously taken into account, I would like you to discuss this matter with Souvanna at earliest time you judge opportune. To minimize possibility of damage to our essential relationship with him, you should present proposal as an idea we are considering--with view to obtaining his acquiescence but short of making direct request for authority. You should note that basic function of this installation--like others on SEA mainland--would be precise navigational control of aircraft; that MSQ-77 is a quantum jump beyond TACAN facilities already emplaced within Laos; and that USAF has necessary equipment and personnel for immediate installation. Such a facility may have appeal to Souvanna with respect to US operations in Laos (though we are aware that you believe tactical changes would in fact be minimal at least initially). You will, of course, have to acknowledge capability of system to direct air strikes against North Vietnam. In other words, you should avoid both exclusive concentration on offensive use against North Vietnam of ground installation in Laos and dissimulation that would jeopardize our relationship of candor and trust in event we decide to approve emplacement and installation should ultimately be exposed./3/

/3/In telegram 7712 from Vientiane, June 14, Sullivan reported he had discussed hypothetically the question of MSQ-77 with Souvanna the morning of June 14. Souvanna's reaction was "cautious, but generally positive." If the unit were to be installed, Souvanna suggested that it must be done without his knowledge. Technicians servicing the site would have to be civilians or military personnel with civilian documentation. The site would need to be camouflaged both physically and electronically, and would need demolition units attached for emergency use. (Ibid., DEF 15 LAOS-US)

3. If Souvanna does not object and you can now agree to positioning of MSQ-77 at Site 85, you may wish to provide your judgment as to whether USAF personnel need be under shallow cover and on any necessary restriction on pattern of crew rotation by helo.

4. I plan to review this proposal with the Secretary on basis of your report.


The Telegram from Ambassador Sullivan to The Department of State on June 14, 1967 indicated that Souvanna would cautiously go along with the installation of an MSQ-77 at Site 85. A Telegram from The Department of State on June 29, 1967 to the Embassy in Laos gives the go ahead for the installation if new objections are not brought forth by Souvanna.

294. Telegram From the Department of State to the Embassy in Laos/1/

Washington, June 29, 1967, 4:43 p.m.
/1/Source: Department of State, Central Files, DEF 17 LAOS-US. Top Secret; Exdis. Drafted by Hamilton; cleared with Habib, Rear Admiral Lemos of DOD/ISA, Arzac, Salans, and Brigadier General Dobson of the Joint Staff, J-3; and approved by Kohler. Repeated to JCS, CINCPAC, and COMUSMACV.
218801. MSQ-77. Refs: A. State 207815./2/ B. Vientiane 7712./3/ Joint State/Defense message.
/2/Document 290.
/3/See footnote 3, Document 290.

Part One: For Vientiane

1. We are pleased that Souvanna reflects a generally positive attitude about MSQ-77 installation in Laos. His concerns are fully understood and, except with respect to location, those mentioned in Ref. B can be allayed:

a. Souvanna's position that he would wish to be able to deny knowledge of installation is understandable. If facility were to be exposed, we would propose to acknowledge presence of navigational aid in area where such facility woefully deficient. In such circumstance, is it likely that Souvanna would be willing to acknowledge in general that US has provided navigational aids to RLG, so that question in fact directed toward MSQ-77 might be dealt with by allusion to TACANS which we understand Souvanna has approved for use in Laos? We hope in any event that Souvanna would hold in abeyance any comment on "violation" until nature of disclosure precisely known and could be discussed.

b. USAF personnel will operate facility, [less than 1 line of source text not declassified].

c. Equipment would be prepared for emergency destruction at time of installation. In event of communist attack, we will wish to count on Vang Pao for vigorous defense long enough to evacuate personnel but not, if pressure heavy, for defense of equipment.

d. Previous communications should provide basis for assurances that every feasible measure will be taken for physical and electronic camouflage.

2. Taking into account technical requirements (primarily line-of- sight feature and range of system) and security and low visibility requirements, it remains Washington judgment that Site 85 is not only best but only feasible location. We have understood your analysis supported this judgment. Unless you have alternate proposal we could quickly review, believe justification for this selection must stand.

3. Secretary Rusk has determined that military requirement justifies accepting potential political liabilities and we are hopeful Souvanna will understand basis on which this difficult decision made. In light contradiction (Ref B) between Souvanna's desire for reassurances on specific points and his wish not to know what we are doing, will have to leave to your judgment how best to bring him to awareness that we have taken his concerns (which we share) fully into account in reaching decision to proceed. Advise action taken to square your account with him.

Part Two: For JCS

4. Unless report requested from Vientiane in para 3 above indicates new objection, you may proceed installation of MSQ-77 at Site 85, subject to coordination of arrangements for installation and continuing support with US Ambassador Vientiane by appropriate USAF authority.


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