Aviation Accident Summaries

Aviation Accident Summary ANC96LA111

HEALY, AK, USA

Aircraft #1

N58269

McDonnell Douglas MD369D

Aircraft #2

N5246E

Cessna 185

Analysis

The McDonnell Douglas MD-369 helicopter, N58269, was flying in an easterly direction about 400 feet msl. The pilot said he was looking for potential landing sites which would allow the passengers/geologists to explore nearby rock formations. The pilot looked up and saw an airplane head-on an instant before impact. The helicopter's tailrotor drive shaft was severed in the impact, and the helicopter soon begin to spin. The pilot was able to make a partially controlled emergency landing in brushy terrain. The helicopter pilot said prior to impact with the airplane, his forward vision was partially restricted due to sun glare. The Cessna 185, N5246E, was flying in a westerly direction. The pilot said he saw the helicopter when it was slightly below, and directly in front of him. He said he just had a moment to pull back on the control wheel and try to turn left. He felt an impact, and later discovered the helicopter's tailrotor had damaged the airplane's lower fuselage, and knocked the tailwheel off. He was able to continue to his destination and made an uneventful landing.

Factual Information

On August 4, 1996, about 103 Alaska daylight time, a McDonnel Douglas MD369D helicopter, N58269, operated by Tundra Copters, and a wheel equipped Cessna 185 airplane, N5246E, owned and operated by Talkeetna Air Taxi, collided in midair in the vicinity of the Vanert Glacier, located about 28 miles southeast of Healy, Alaska. The commercial certificated pilot and four passengers aboard the Cessna were not injured. The commercial certificated pilot of the helicopter and the three passengers aboard reported minor injuries. Both aircraft were being operated under 14 CFR Part 135 as on-demand air taxi flights in visual meteorological conditions. The helicopter was carrying three geologists employed by a mining company, and the airplane was carrying four Italian Nationalist tourists. Telephone interviews between the NTSB investigator-in-charge and the pilots of the two aircraft on August 4 disclosed the following information. The helicopter pilot stated he was looking for a landing area to allow his passengers to do mining surveys. He said he was flying in an easterly direction, and the sun was partially in his eyes. He was flying the helicopter approximately 400 feet above the ground, looking down to find a landing site. When he looked up and forward through the cockpit bubble, he saw the Cessna's main landing gear head on and an estimated 20 feet away. He said he felt an impact, and then severe vibration. The vibration was so severe he was unable to read any of the instruments in the cockpit. He elected not to make any pitch or power changes because the helicopter was still flying, and he was concerned that any control inputs might further decay aircraft control. He allowed the helicopter to descend towards a sloped area, and when about 50 feet above the ground, he applied power to stop the descent. When the power was applied, the helicopter begin to spin quickly to the right. The pilot said although the tail rotor drive shaft had been severed, probably upon impact, he was able to maintain some lateral control and minimize lateral drift until the helicopter impacted slightly sloping, brush covered terrain. The pilot and three passengers were able to exit the helicopter on their own. The airplane pilot said he was flying in a westerly direction, when he saw a helicopter "all of a sudden" and when it was very close. He thought the helicopter was about his altitude and nearly head on. He said he just had time to pull back and turn the control yoke to the left prior to hearing and feeling an impact somewhere in the tail section. He called for another airplane that was flying in the same general vicinity to come and look his airplane over. The pilot of the other airplane reported the accident airplane was missing a tailwheel. The pilot of the accident airplane elected to fly to his base of operations at Talkeetna, Alaska, where he landed without incident. The Cessna airplane was examined after the accident by a Federal Aviation Administration (FAA) Inspector. He reported it appeared the tail rotor of the helicopter collided with bottom of the Cessna's fuselage in front of the tailwheel, and continued aft, striking and removing the tailwheel.

Probable Cause and Findings

The inadequate visual outlook by the pilots of both aircraft, and their failure to see and avoid the other aircraft. A factor associated with the accident was sunglare affecting the helicopter pilot's vision.

 

Source: NTSB Aviation Accident Database

Get all the details on your iPhone or iPad with:

Aviation Accidents App

In-Depth Access to Aviation Accident Reports