Linneus plane crash caused by pilot error, say experts

HOULTON – The National Transportation Safety Board has determined that pilot error was the cause of a July 19, 2000, crash of a Canadian cargo plane in Linneus that killed the pilot and co-pilot.

The probable cause of the crash of the twin engine Grumman Gulfstream I was “the pilot-in-command’s failure to maintain minimum control airspeed, which resulted in a loss of control,” according to the NTSB’s final report released last week.

Killed in the crash were Christopher John Dunn, 46, the pilot and president of Airwave Transport based in Mississauga, Ontario, which owned the plane, and co-pilot Robert Hughes, 31.

The NTSB noted that factors in the accident were clouds – an indication that ice may have been a problem – and “loss of engine power for undetermined reasons, while in cruise flight above the airplane’s single-engine service ceiling.”

The single-engine service ceiling is the altitude at which a twin-engine plane can safely fly with one engine, based on atmospheric conditions, weight and balance of the plane.

In its report issued earlier last month, the NTSB calculated that the single-engine ceiling for the Gulfstream I prior to the crash was 14,000 feet.

The plane was on a flight from Moncton, New Brunswick, to Montreal, Quebec, when it crashed at 12:31 a.m. Eastern Daylight Time along the banks of the Meduxnekeag River, about eight miles south of Houlton. The crash occurred about two minutes after the plane lost power in its left engine.

At that time, the plane was cruising at an altitude of approximately 16,000 feet, 2,000 feet higher than its calculated single-engine ceiling.

Citing a Federal Aviation Administration bulletin, the NTSB’s factual report noted that “when the airplane is above its single-engine service ceiling, altitude will be lost … the altitude should be maintained if it is within the capability of the airplane. If the airplane is not capable of maintaining altitude with an engine inoperative under existing conditions, the airspeed should be maintained at the single-engine best rate-of-climb speed so as to conserve altitude and as long as possible to reach a suitable landing area.”

The crew had declared an emergency to Boston Regional Air Traffic Control indicating that they could not maintain altitude, and requested a route to the nearest airport, which would have been in Houlton.

Hughes, the co-pilot, is later heard on the cockpit voice recorder telling Dunn to “keep it up, keep it up,” shortly after informing him that the plane was losing airspeed.

The NTSB did not cite a possible reason for the failure of the left engine. The report noted that examination of the engine after the crash revealed nothing that would have accounted for the engine’s unintended shutdown prior to the accident.

It was noted in the final report, however, that the engine failure occurred approximately two minutes after the crew had stopped cross-feeding fuel from one engine tank to the other to correct a fuel imbalance in the wing tanks.

The factual report issued last month also noted that the Canadian Meteorological Center at Gander, Newfoundland, had issued a weather warning for severe icing for the plane’s flight path. The NTSB final report notes, however, that the plane’s crew did not report, nor did they discuss, any weather-related problems around the time of the crash.

The factual report also says that there were no reports from other pilots over Maine at the time of problems with icing or turbulence.

The Gulfstream I was equipped with an anti-icing system.