Narrative:A Dassault Falcon 10, F-BYCV, skidded off the end of the runway during landing roll at Hailey-Friedman Memorial Airport, Idaho. The two pilots were not injured, but the aircraft sustained substantial damage.
The aircraft had recently been purchased in Paris, France, and the accident aircraft was on a multi-day flight to bring it to the Friedman Memorial Airport. The previous leg had been from Saskatoon, Saskatchewan to Great Falls, Montana. The previous flights had been without problems or discrepancies, except for an intermittent antiskid problem on the left system and a rather poor braking action noticed during a long taxi after landing in Iqualit.
The crew executed a visual approach for a "flaps 52" full-stop landing on the 6,602 foot long runway 31. Both crew members reported that the aircraft became established on final at a speed of approximately landing approach speed (Vref) plus 15 knots to Vref plus 20 knots. According to the pilot in command, because of the reported winds, he expected to experience a five to eight knot tailwind at touchdown. He therefore began reducing power on final in order to insure a touchdown "on the numbers," right at Vref speed. According to the first officer, who had about eight times as many flight hours in this model aircraft as the pilot in command, this reduction in power caused the aircraft to establish a descent rate that resulted in a "firm" touchdown and a bounced landing. The pilot in command thought that the aircraft had simply bounced hard enough for the gear oleos to extend, but not hard enough for the wheels to come off the ground.
He then began the thrust reverser activation/braking process soon after the initial touchdown. Both pilots said that after reverse power was selected they heard a noise associated with engine acceleration, but that it did not sound like they expected it should with the reverser doors in the deployed position. They both also noticed that the aircraft was not slowing as expected. The pilot in command then applied more reverse power and initiated strong braking, but the aircraft still failed to slow. He therefore moved the reverse levers back to the stowed position, after which the first officer physically checked the main thrust levers in the idle position.
Because the aircraft did not appear to be slowing and because his attention was focused outside, he again selected reverse power without determining if the TRANS or REV lights had illuminated. Also, at about this same time, because he did not detect the "strong braking action" which he had expected and because of the previous antiskid problems, the first officer moved the red parking/override brake handle to the number two/full override position. At this point, the pilot in command continued to apply full toe brake pressure and, since his training had taught him to move the parking brake handle to the number one/mid position during emergencies, he moved the red brake lever from the number two position to the number one detent.
Then, because it felt and sounded as if power was being added, and because the aircraft did not appear to be slowing, and maybe even accelerating, the pilot in command moved the red brake lever back to the originally selected number two position.
As the aircraft neared the end of the runway, the first officer also began use of the toe brakes, but that resulted in "... no apparent effect." The aircraft eventually departed the end of the runway, skidded across open terrain, and passed through a chain-link perimeter fence. It then skidded across Highway 75, experienced a nose gear collapse when it impacted the edge of an asphalt bike path, and ultimately came to rest in a city park.
Probable Cause:
The pilot-in-command's improper procedures. Factors include failure of an electrical relay, inoperative thrust reverser, poor crew coordination, and the second-in-command's improper procedures.
Accident investigation:
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Investigating agency: | NTSB |
Status: | Investigation completed |
Duration: | 11 months | Accident number: | SEA93FA186 | Download report: | Final report
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Classification:
Runway excursion
Sources:
» Flight International 1-7 March 1995 (12)
» Flight International 22 December 93-4 January 1994 (11)
» NTSB
Photos
Map
This map shows the airport of departure and the intended destination of the flight. The line between the airports does
not display the exact flight path.
Distance from Great Falls International Airport, MT to Hailey-Friedman Memorial Airport, ID as the crow flies is 494 km (309 miles).
This information is not presented as the Flight Safety Foundation or the Aviation Safety Network’s opinion as to the cause of the accident. It is preliminary and is based on the facts as they are known at this time.