In Jan 1969, 3 men were sent from the 1st Mobil Communications Group (1st Mob) in the Philippines to Udorn AB Thailand , Tsgt Juan A. Maldonado (team chief), Sgt Bill Chambers III,and myself, Sgt Donald Deidrich ( I was chosen as I had been on the team that had installed the TACAN there 6 months before). We were to repair the TACAN at LS-36 and train some personnel at the 1973 Comm sq at Udorn. When we arrived at Udorn we found that another man, in country, from the !st Mob, that had been re-directed, had repaired the TACAN at LS-36 and then went to PS-21 ( 20-30 mi south west of Saravan ) to repair that TACAN, it was decided to send two of us to Ubon to repair it, Bill and I departed for Ubon. There we were supported by the 20th SOS Pony Express, about the 17th of Jan we heard about the accident at LS-36 TACAN site. I heard from numerous people, My Commander, Pony Express , and 1973 comm personnel that I knew, and the accounts are very much in agreement. The CH3 Pony Express left Udorn with 8 people ( 5 air crew, 3passengers,Col Bolant (?) Juan and the new TACAN maintenance man ) and 10 barrels of diesel fuel, They arrived at LS-36 and found that the Air America Hughey was on a mission and they would have to wait. It was decided to fly the CH-3 to the TACAN site. There was a restriction on the landing anything bigger than a UH-1 at the site as the pad was very small and the winds were unpredictable. During the landing one of the air crew heard something about the "emergency brake" over the intercom, the chopper rolled forward and went over the edge of the hill ( almost a cliff ) tipped over and exploded. Three people were thrown / jumped clear, they were the crew chief ( I think), a door gunner, and the 1973 Comm sq TACAN man. All three were injured and evacuated back to Udorn and then to the Philippines. I don't remember any names other than those I mentioned. LS-36 was lost to the enemy on the 1st of march 1969, the TACAN site was destroyed by air strikes. An account that mentions the loss of this chopper can be found on the Air Commando web site, under the 20th SOS. Thank you very much for listening to me, and if I can be of any assistance help please let me know.