Test

The crew (four technicians and three pilots) departed San José-Juan Santamaría Airport in the morning on a post maintenance test flight. En route, in unknown circumstances, the airplane went out of control and crashed into the gulf of Nicoya off Puntarenas. The wreckage was found 1,2 km east of San Lucas Island. All seven occupants were killed.

The Aero Spacelines 377MGT was a converted Boeing Stratoliner. Prototype N111AS first flew on March 13, 1970. In the following period flight testing was carried out, a.o. at Edwards AFB. The accident occurred during the sixth takeoff of Flight Number 12 following the scheduled shutdown of the engine number one at about 109 knots IAS. The takeoff was being made on runway 22 and the wind was from approximately 200 degrees at about 10 knots. Rotation occurred at about 114 knots and several seconds after rotation, according to one witness, the aircraft turned and rolled to the left, settling as it did so. The left wingtip subsequently contacted the ground, causing a severe yaw. The forward fuselage struck the ground, causing the flight deck to be destroyed. The test flight was under FAR Part 25 certification program.
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The pilot, sole on board, departed Kingman-Clyde Cessna Field on a local test flight on this first Cessna 340 prototype. While flying in the vicinity of the airfield, he lost control of the airplane that crashed in an open field. The aircraft was destroyed and the pilot was killed.

The crew (two technicians and two pilots) was engaged in a test flight, the third of this model, part of the certification program. En route, an unexpected situation occurred and all four crew members decided to bail out and abandoned the aircraft that dove into the ground and crashed in a field located in Beit She'an. While all four occupants were uninjured, the aircraft was destroyed.

The crew departed Eglin AFB on a local test flight on board this aircraft that was fitted with radiological test equipment for Project "Have Doughnut". Following an uneventful mission, the crew was approaching the airbase when he encountered foggy conditions. On final, the airplane crashed into the Choctawhatchee, about 2,5 miles short of runway threshold. Both crew members were rescued while the aircraft sank.

The pilot departed Jackson-Reynolds Airport on a local test flight to check the radio systems. Just after liftoff, while in initial climb, the right engine caught fire. The pilot completed a wheels-up landing in a swamp near the airport. He was slightly injured and the aircraft was damaged beyond repair.

Shortly after takeoff from Los Angeles International Airport, while climbing, the left engine failed. The pilot-in-command lost control of the airplane that crashed in flames onto a house located in the district of El Segundo, by the airport. The aircraft and the house were totally destroyed and all four crew members were killed as well as two people in the house.

The crew was engaged in a local test flight out from Norman Airport, consisting of various tests (stalls) in specific conditions. In flight, the pilot-in-command engaged the aircraft in a stall when control was lost. The airplane entered a dive and eventually crashed in a wooded area located in Rosedale, about 28 miles southeast of Norman Airfield. The aircraft was destroyed and all threes occupants were killed.

The crew was involved in a local test flight after the airplane has been rebuilt following another accident. After takeoff, the airplane went out of control and crashed by the runway. Both occupants were seriously injured and the aircraft was destroyed.

While the aircraft was being taxied into the hangar on 9 March 1969 for a Check III inspection the port elevator was damaged by contact with a set of passenger stairs. It was decided therefore to change the elevator during the inspection. The aircraft was test flown by the pilot-in-command after the inspection at 0600 hours on 18 March 1969. During the flight it was discovered that the elevator trim was ineffective. Subsequent examination revealed that the elevator trim tabs had been rigged in opposition, one up and one down. The aircraft was therefore returned to the hangar for rectification. A further test flight was scheduled at 0600 hours on the following day, i.e. 19 March. After completing the ground run and preflight check the aircraft was again returned to the hangar for further work on the elevator trim mechanism. One of the engineers reported that the elevator trim was "very stiff". The work was carried out by the pilot-in-command and an engineer, who were observed to carry out a functional check of trim operation after the work was completed. At 0730 hours the aircraft was lined up on the runway for take-off. The take-off and climb out were observed by two experienced witnesses and appeared to be quite normal. After a period of about two minutes and at an estimated height of 700 ft the aircraft made a turn to port through approximately 1600 at an estimated 300 bank angle. The aircraft was then seen to recover from the turn and immediately enter a dive which became progressively steeper until the aircraft struck the ground and burst into flames. All four crew members were killed.