Mooney M20 Beverly, MA
- Thread starter ldhilljr13
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Compression loss, very rich mixture in that cylinder?
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- Lancaster, Pennsylvania
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- Rick A
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Even if the Mooney was a little over gross and it was a hot summer day, over 5000' of runway length should have left enough room remaining on the runway or airport property to survive an aborted takeoff. There are no trees close to the departure end of r/w 16.
Reportedly the stall/spin occurred over the airport. Witnesses, and the engine monitor confirmed he powered back, then increased the power while still over the runway. The startle effect causing indecision, then deciding to continue the climb and quickly return to land was likely the beginning of the end. If a loose spark plug was truly the cause of the engine acting up, he wasn't thinking clearly (panicked?), costing two lives.
Reportedly the stall/spin occurred over the airport. Witnesses, and the engine monitor confirmed he powered back, then increased the power while still over the runway. The startle effect causing indecision, then deciding to continue the climb and quickly return to land was likely the beginning of the end. If a loose spark plug was truly the cause of the engine acting up, he wasn't thinking clearly (panicked?), costing two lives.
bonefishpete
Cleared for Takeoff
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My Mooney 201 had a habit after O/H to stick the valve right after TO. Surprisingly a lot of power loss. It only did it momentarily then cleared. Four times I flew straight one time I landed on the remaining runway. Mechanic kept saying it was something else until the last time it bent the push rod tube.
Lower the nose and start looking where to put it was always the plan.
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- Rick A
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Yes, when the engine acts up on the runway, or during the initial climb out, it should be a quick and near instant decision to chop the throttle and put it down straight ahead. You did good.
When a partial power loss on the runway is not accompanied by any roughness or instrument abnormalities, it can be a tough call.
An overhead cam gone bad in a Lyc 360 is something that's not uncommon to that engine, and can be a real killer. You only know something is wrong when the expected climb performance isn't there, and by then the runway is now behind you.
True, but for a half-decent pilot owner a degrading camshaft shouldn't be a surprise. One of the major benefits of ownership is getting to know the aircraft and its performance, which in turn makes it easier to spot the loss of it.
If my typical departure profile gives me 1000fpm and wheels off the runway in 1500ft, I'll notice when it takes 2500ft to get airborne and my climb rate maxes out at 750fpm.
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- Lancaster, Pennsylvania
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- Rick A
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Yes, for sure. But in an incident I shared here a couple years ago the owner rarely flew with passengers, or near gross weight. And actually didn't fly his Mooney 180hp C model much at all, which was probably why the front lobe on the camshaft was trashed.
It was a hot August late afternoon day with no wind. During the takeoff roll on a 4100' runway (400' MSL) I wrote off the anemic acceleration to hot, heavy and 20 less horsepower than the Mooney I am familiar with (M20J).
None of the three of us (all pilots) were alarmed until after rotation, gear up (Johnson Bar) and finally waking up to the reality of a very poor initial climb rate. The engine sounded and felt completely normal. At that point there was not enough space left remaining to land and stop before running down a small hill, through a chain link fence, and into a line of stopped rush hour traffic on the road adjacent to the airport's west perimeter.
The turn back was commenced (not in a panic) at low speed, shallow bank, low altitude and coordinated. Just (IMO) in the wrong direction as the PIC owner took his own route back to his choice of runway which had the engine quit, would not have left any good off-airport options.
- #102 post from August 2025