Accident Details
Probable Cause and Findings
The failure of the pilot to abort the takeoff roll. Factors contributing to the accident included the failure of the aircraft to accelerate for undetermined reasons and the trees.
Aircraft Information
Registered Owner (Historical)
Analysis
HISTORY OF FLIGHT
On June 16, 2003, approximately 1830 Pacific daylight time, a Downer RC-3 "SeaBee" amphibious aircraft, N6723K, recently purchased and being operated by an airline transport pilot, was destroyed after impacting trees following a takeoff run at Western Airpark (92W) near Yelm, Washington. The left seat pilot-rated passenger received serious injuries, while the right seat airline transport pilot sustained fatal injuries. Visual meteorological conditions existed, and no flight plan had been filed. The flight, which was personal, was to have been operated under 14 CFR Part 91. The flight was originating at the time of the accident.
As reported on the Pilot/Operator Aircraft Accident Report (NTSB From 6120.1/2), and in an interview with the NTSB investigator-in-charge (IIC), a senior NTSB investigator, and an FAA inspector, the passenger reported that he had just purchased the aircraft on the morning of the accident, and to the best of his knowledge it had not flown in a couple of years. The passenger stated that he and the right seat first pilot had agreed that the first pilot would do the flying during the repositioning flight to the first pilot's home base. The passenger further stated that while he was helping load airplane parts into a van, the first pilot was looking the airplane over, and that when he tried to start the engine, "...it started right up the first time." The passenger reported that he and the first pilot checked the fuel level and it was between 35 and 40 gallons, and that the first pilot also checked the fuel visually with a dipstick and a container. The passenger stated that the first pilot ran the engine a second time, checked the magnetos and let it warm up. The passenger recounted that the first pilot cycled the propeller a number of times and thought he tried reverse, but wasn't "totally" certain about this. The passenger reported that he didn't remember if the first pilot had done a full power run-up on the engine, or whether he had set the parking brake. The passenger stated that he taxied the airplane for departure, but he could not remember if the parking brake was on or off prior to taxiing, and that he didn't remember the airplane pulling to the left or right while taxiing, or the brake "grabbing" or "binding up." The passenger continued by saying that when he approached the end of the runway he made a wide right turn to line up with the runway, but overshot the centerline and had to make a 360 degree turn to get lined up. The passenger stated that during this time frame he sensed the first pilot was in a hurry to get home, as indicated by the first pilot's reactions to him for overshooting the centerline and taking too much time to get the airplane lined up for takeoff. The passenger further stated that when he did get aligned with the runway the first pilot took the controls and advanced the throttle, but that he wasn't sure if he advanced the throttle to the full forward position or not. The passenger also related that after the throttle was advanced he didn't feel like the airplane was accelerating properly. "I asked [the first pilot] if the airplane was accelerating properly and he said 'Yes.' During the acceleration I noticed a reading of 50 miles per hour (mph) on the airspeed indicator, but did not sense a continuous acceleration. I asked [the first pilot] if the power settings were proper and he replied 'Yes.'" The passenger reported that as the takeoff roll continued and the end of the runway was approaching, he again did not sense the airplane accelerating, that he thought 65 mph or 70 mph was flying speed, and that they might have been a little over 50 mph and not accelerating. The passenger stated, "I then asked him [the first pilot], 'You want me to put some flaps out?' and his response was 'No.' A moment later the airplane went off the end of the runway down into a ravine. It never flew. I do not know why the airplane failed to obtain flying speed, nor do I know why [the first pilot] continued the takeoff when it seemed to me that something was wrong. I did not notice any malfunctions during the takeoff run that would explain the aircraft's failure to accelerate properly." The passenger said he thought the first pilot had one hand on the throttle and one hand on the yoke, but he didn't notice if he was making any power adjustments. The passenger said he didn't observe any tach reading, that his feet were flat on the floor, his hands were in his lap, and the airplane appeared to be tracking normally on takeoff. The passenger also stated that he didn't think the first pilot had become incapacitated and that there was no departure briefing.
Six witnesses who live on the airport from where the airplane was departing furnished the NTSB investigator-in-charge with written statements.
Witness #1, a retired commercial airline pilot, reported observing the aircraft taxi to the west end of the runway, do a run-up, and depart. The witness stated that about 1,400 feet from the west end of the airport the airplane appeared to be traveling about 45 mph to 50 mph. "I continued to observe the aircraft and it did not appear to accelerate any more, but continued with what appeared to be max [maximum] power. I do not recall any roughness in the engine as it passed my point. The aircraft continued the takeoff roll but did not appear to be accelerating. I was waiting to see an abort, but the aircraft continued to the end of the runway and then traveled on another 100 feet of grass overrun before dropping down a very steep embankment. At that point the engine noise stopped."
Witness #2, a retired commercial airline pilot, reported observing the aircraft from in front of his house, which is located midway down the 2,800-foot runway. The witness stated the aircraft was in front of a hangar with the engine running at low power, approximately 1,500 rpm. "The engine sounded normal to me at that time, although I didn't focus on it." The witness further stated that he observed the airplane taxi to the west end of the runway for run-up, but since he could only see the middle one-third of the runway from his house, he couldn't see the aircraft during the run-up, or hear what the engine sounded like. "Later we heard the aircraft power up for takeoff. As the aircraft passed the mid-point of the runway, I estimate its speed at 45-50 mph, and the engine sounded terrible. It was either mis-firing or it had stuck valves, because it was missing pretty badly. I remember thinking that this must be a full power run during high speed taxi and that the pilot would certainly abort, but as he disappeared past my neighbor's hangar to the east, I realized that he was continuing the takeoff." The witness reported that he did not see the departure of the aircraft off the east end of the runway.
Witness #3, an airline transport pilot and licensed airframe and power plant mechanic, said he was familiar with the normal engine sounds peculiar to the geared engine installed in the accident aircraft. The witness reported that he had an unobstructed view from the yard of his house from the time it taxied out to the time it disappeared from view off of the eastern end of runway 9. The witness stated that at the time the airplane was doing a run-up in the vicinity of the hangar, he did not notice any unusual engine sounds. "The aircraft taxied by within a hundred feet of our location and the engine sounds were normal at that time. I watched the aircraft go by my position and did not visually notice anything unusual." The witness reported the aircraft proceeded to the west end of runway 9, into the paved turnaround area, and stopped for a short time prior to beginning its takeoff roll, with no further run-up conducted at the runway. The witness further stated that as the airplane started its takeoff roll down the runway, he noticed that the engine did not seem to be producing full power, and was not running smoothly "at that high power setting." The witness also related that there was no surging from the propeller, and that the sounds he heard were consistent with a carburetion problem. The witness reported, "The aircraft did not appear to accelerate normally, and my initial thought was that the pilot was doing high speed taxi testing, although it appeared that the flaps were at least partially extended. The witness said the tailwheel rose clear of the runway and the aircraft continued in a nose high attitude the full length of the runway before going over an embankment where it disappeared from view. The witness reported the power was never reduced and the main wheels never appeared to leave the pavement until the aircraft ran off the end of the runway.
Witness #4, a corporate pilot who resides on the airport, reported observing the airplane coming down the runway [on its takeoff roll] going slow, "making noises," and the tail not leaving the ground. The witness stated, "It looked like it was traveling about 40 mph. I could not see it past the condo hangars, as they blocked my view. It did not get airborne to the east."
Witness #5, a corporate pilot who resides on the airport, reported the he could clearly see the entire runway, with the exception of the departure end of runway 09. The witness stated that he noticed the airplane pass by his house as it was taxiing to runway 09 and nothing unusual was noted. The witness further stated, "...[I] observed the Seabee rolling down the runway on centerline. However, the engine didn't sound right. It wasn't extremely obvious though what it was. Something like the tone changing just enough to indicate to me that it wasn't developing full power. I then observed the airplane passing me at midfield, that it was traveling at approximately half speed that I considered necessary (approx 30 - 40 mph)." The witness stated that he continued to watch, and at two-thirds down the runway there was no eviden...
Data Source
Data provided by the National Transportation Safety Board (NTSB). For more information on this event, visit the NTSB Records Search website. NTSB# SEA03FA106