On the day of the accident, the pilot decided to take his Mooney M20C on a flight around the traffic pattern at his home airport in Warwick, New York, to practice a few takeoffs and landings.
After pulling the airplane out of the hangar, he performed a preflight inspection. He then performed an engine run-up, then back taxied on the runway for takeoff.
Once he was in position for takeoff, he advanced the throttle until it was full open, and at 65 mph and about 2/3rds of the way down the runway, he rotated. He immediately realized that the engine was not producing full power, and attempted to advance the throttle further, but the throttle seemed as though it was not advancing completely. He then nosed the airplane down to attempt to stay in ground effect and gain some airspeed.
A lake was at the departure end of the runway, and he was already approaching trees on the opposite bank. He then picked a spot between the trees, turned the fuel off, and pulled the aircraft into a full stall prior to impact.
Post-accident examination of the airplane revealed that the fuselage and wings were substantially damaged. The pilot sustained serious injuries in the crash.
Further examination revealed that the throttle cable would resist efforts to fully open the throttle and would only move the throttle arm on the carburetor about 1/2 an inch, and when the throttle was fully open, the entire throttle cable would move through the firewall and bulge. After disconnecting the cable from the carburetor, the cable was found to be still under load, until a loose stand-off clamp that connected the throttle cable to the firewall was repositioned, which then allowed the throttle to function properly through its full range of motion.
Probable Cause: A loose stand-off clamp, which resulted in a throttle assembly malfunction, and the inability of the engine to produce full power during the attempted takeoff.
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This April 2021 accident report is provided by the National Transportation Safety Board. Published as an educational tool, it is intended to help pilots learn from the misfortunes of others.
Can’t understand why he didn’t see he wasn’t getting full RPMs upon starting takeoff roll. I always hold brakes and advance full throttle, check RPM, oil Pressure. And all instruments in green. Specially on first takeoff.
Unfortunately this was a short runway (2150′). But regardless, a critical engine check on all takeoffs is to monitor the acceleration to the rotation point, which would be at about the 1000′ marking ahead for this airplane. When the airspeed becomes active, compare the movement of the needle to the rotation point. If it appears that rotation speed will not be reached until well after the rotation point, there’s an engine problem. Hopefully you will be able to abort early in the takeoff roll, safely exit the runway, and investigate.
It amuses me (sadly) that quarter $million airplanes have all the mechanical integrity of my 1953 Plymouth. I had a similar throttle cable holding clamp assembly come loose on my lawn mower last year. Good thing I spotted the problem before my lawn mower stalled and nosed-over due to loss of power.
Regards/J
A ’62 M-20 is worth about $60k, so, far from $250k. [ it’s not a Cirrus].
It’s was designed about the time your Plymouth was, with mechanical throttle controls.
Simple hardware is highly reliable, vs today’s ‘drive by wire’ cars. One of the many computers decide to ‘blue screen’ and you’re walking.
I’m glad to hear that your mower didn’t stall and crash. [ sarc! ]
[ but then, ‘Paul’s law, states that you can’t fall off the floor’ ].
Makes perfect sense, replace a tried and true single mechanical component with hundreds of electronic components and soldier joints that can’t be checked.
Brilliant deduction!
Flying and maintaining small airplanes requires a measure of mechanical awareness that comprehends the subtleness of a loose cable housing and lost motion to the core wire; the core wire that actually moves the throttle, mixture, and propeller controls. There are other examples to be found in any light airplane, but understanding the simplicity-or complexity-around mechanical design and function is vital to staying alive.
WOW…!! this pilot has 8 hours in the airplane, which I’ll assume he recently bought, and crashes it because of a jammed throttle cable..!
So, the annual 4 months prior didn’t detect a poorly routed throttle cable…..very sad.
From the FAA registry, the aircraft is flying again…..well , at least it has a current registration.