HAVNAER RALPH MILTON

Narrative

Description of the accident involving 66-16601, 66-16206, and 66-16592: The aircraft made a landing at Cobra Pad and troops were loaded aboard. A radio call was monitored in which Blackjack Six, 12th group commander asked the status of the operation, advised the command and control helicopter that the weather was marginal over the area of operations and suggested a delay if possible. The command and control aircraft departed Cobra Pad for a weather check and determined that although the weather was marginal in all quadrants the weather over the intended landing zone was broken and called the lead aircraft (Blue 1) to bring the flight out to the area of operation.. During take off, climb out and enroute to the area of operation the flight encountered fog, clouds and haze that restricted visibility. The flight of ten lift helicopters proceeded northwest from Bearcat at an altitude of 1000 feet in a staggered right formation until over the area of operation. The flight leader (Blue 1) had visual contact with the command and control aircraft and gunships, but stated that the command and control aircraft did not have the flight in sight. After proceeding northwest of the area of operations, the flight leader informed the command and control aircraft of his location and that he was encountering clouds at 1000 feet. He did not have visual contact with the ground or the command and control aircraft at that time. He informed the command and control aircraft he was going to establish a left hand orbit, as he was passing the area of operations. The command and control ship acknowledged the left orbit and suggested the flight go to 900 feet as the weather was better at that altitude. The flight leader established a standard turn to the left and descended to 900 feet, after turning from northwest through south and east to a heading of 060 degrees he entered a cloud. Immediately upon emerging from the cloud the flight leader saw an unidentified helicopter approaching at his immediate right front at the same flight level. The flight leader took immediate evasive action by breaking down and left. He observed that the unidentified helicopter, later determined to be the command and control ship, attempted to pull up and left. The rotor blades of the second aircraft in the formation (Blue 2) struck the tail rotor section of the unidentified aircraft, severing it from the fuselage.. The main rotor and transmission were observed separating from Blue 2 and the main fuselage crashed inverted into a swampy area.. The command and control aircraft exploded upon impact in the air.. The other aircraft of the flight took evasive action and were able to avoid the fire ball and falling debris with the exception of Blue four, the aircraft directly behind Blue 2. Blue 4 flew into the explosion and debris. The rotor system and tail boom were torn from the aircraft and it crashed and exploded upon impact. Both the command and control aircraft and Blue 4 continued to burn on the ground until the fire was extinguished with the help of air force fire equipment located at Bien Hoa Airbase. Debris were scattered over a wide area and there were no survivors among the twenty-nine persons aboard the three aircraft.