The private pilot reported that the accident flight was the Mooney M20E’s first flight after being painted.
After completing a preflight inspection, he started the engine and observed a decrease in power.
He leaned the mixture slightly, and the engine rpm returned to normal idle speed. He reported that during the engine run-up, he noticed that the engine had a delayed response when he increased the throttle, but that the run-up otherwise revealed no anomalies.
The pilot said the takeoff roll took longer than expected, and after lifting off near the end of the runway, the airplane climbed more slowly than normal.
He said that during the initial climb, engine power had decreased to 2,000 rpm. As the airplane reached about 100′ above ground level, the engine was producing about 1,800 rpm and could not maintain a climb.
The pilot elected to continue straight ahead rather than return to the runway at the airport in Corona, California, and the airplane subsequently descended into trees.
A post-accident examination revealed no anomalies with the airframe or engine that would have precluded normal operation. The reason for the partial loss of engine power was not determined.
Probable cause: A partial loss of engine power during initial climb for reasons that could not be determined based on available information. Contributing to the accident was the pilot’s decision to conduct the takeoff with observed engine deficiencies.
NTSB Identification: WPR16LA039
This December 2015 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.
The only way for a SE airplane to get into the air and continue with a normal climbout is if that engine is producing sufficient power to pull/push the airplane along at or above minimum flying speed. Runups are done for but one reason, i.e. to ensure the engine is operating normally and shows no signs, NONE, of a potential problem that might negatively affect the airplane safely taking off. There were several indications in this case that the airplane would not be ensured of a safe takeoff and climb out with the final sign being the runway used to reach takeoff speed. 70% of takeoff speed reached within 50% of expected takeoff distance is the rule of thumb. If not, power to idle and mash on the binders as necessary to prevent an overrun. This pilot was hoping the airplane would fly but it couldn’t and it told him so several times.
Engine power is one of the items where the « if there’s a doubt, there’s no doubt “ rule applies.
I hope the pilot didn’t pay with his life for not knowing that rule.
Warren Webb Jr says
Agree with all comments. This one is quite baffling. However, maybe he always relied only on the runup for checking the engine. As written above, the engine power was apparently normal after a delayed response so did that result in a hard decision to launch. However the takeoff roll clearly showed a huge problem. Lifting off near the end of the runway? A 3200ft runway, about three times the normal takeoff roll. Halfway through the normal takeoff roll distance (about 500ft) it should have been obvious that flight would not have been possible. None of the engine instruments, nor the noise level, mean anything if the airplane will not reach anywhere near rotation airspeed at the correct point on the runway (about 1000ft). Hopefully he will do this performance check in the future.
Sarah A says
I have been told by someone wiser than me that if it does not work perfectly on the ground. it is unlikely to work any better in the air. Too bad this pilot never received that bit of advice.
Stu Brown says
How many signs does a person need to not attempt a takeoff? All this guy did was confirm there is a problem and he went anyway. Sad…….
It never ceases to amaze me the poor decisions people will make when their lives hang in the balance.
Runup isn’t done because some instructor back in the day taught you to do a runup. If you notice ANYTHING during runup don’t fly.
Howard Fischer says
Why would you continue on if the engine did not come up to power?
Wylbur Wrong says
First flight after painting and the engine was not responding correctly to throttle settings. NO, this is an immediate abort of take-off. I would have left the run up area via the taxi-way not the runway.
I would suspect painting related contamination of the air intake system. That reducing the mixture caused the engine to gain power… Then when it was only producing 1800, the LAST thing you want to do is mixture to full. It has already exhibited an excessively rich mixture problem, from my point of view here in my armchair. And if so equipped, I would have opened the ALT-AIR to try to solve this problem, if I had gotten off the ground. And I would have retracted the gear, one doesn’t need the drag (having a loss of power problem in a complex plane right after departure).
So to answer your question, in this case, I would not continue this flight. I would, instead, have an A&P (if I were not one) take the cowling off and start looking for the reason this engine could not develop and maintain full power.
And, given what the pilot had said, the examining people didn’t list an examination of the air intake system. We do not know if there was or was not any contamination of the air filter with paint, thinner, or tape. The same holds true of the Mooney Ram air (I’m not sure if this one had that) system having been taped shut. Or any other indication of restrictions to the air intake system.
Yet what the pilot reported sure seems to me that the engine was running rich. But not rich enough, long enough for it to show up on the plugs.