From the Facebook page of Warner Propellor:
Blades half gone but the airplane still flies
The pilot of this DA-42 was going to do a touch-n-go. At the last minute the pilot realized he forgot the landing gear. The pilot quickly added power and flew back to his home airport. The pictures are what was left of his MT Propellers at shutdown. Nearly half the blade is missing and this airplane still flew! The pilot had no idea what had happened to the propellers until he shut down.
I find it hard to believe that the pilot didn’t notice that there was a problem with the propellers.. There must have been quite some vibrations caused by the damaged props. Also the performance degradation must have been quite noticeable.
Would the FADEC system be able to detect the change in prop performance, and try to get the best out of it by changing RPM / pitch to the most efficient setting?
Seeing how neatly rounded the cut on the prop blade, the prop must have been “machined” against the runway surface. Impressive quality indeed, to survive such treatment! But the blades will all have undergone the same treatment so no reason for vibrations there.
No way he could have maintained power with a bent metal prop, too much mass out of balance. Another advantage is that he will only need a gearbox repair.
I cannot believe the pilot didn’t notice the damage.
Most of the prop thrust comes from the outermost 1/3 of the blade(s) and these are the bits which have been chopped off.
If you shorten a blade, the prop governor will increase the blade pitch so as to absorb the engine power, but there is a limit (also there is a limit on the blade AOA) and in this case I’d say there is no way the truncated prop could have absorbed the engine power. The post-go-around climb rate must have been terrible and the cruise performance likewise.
That’s assuming the pilot has any currency on the type…
All three blades or only one? Both props or only one?
Both props, Emir. Sorry, I uploaded the same picture twice. Changed it in the original posting. See the second picture.
Achim: The DA42 has wooden props.
At Shoreham, one renter started up the PA28 with the towbar, took a big chunk (about 20×20mm) out of the end of the prop (which must have vibrated like hell), chucked the towbar into some grass, went for a flight, came back, said nothing, and was never seen again.
I don’t believe either pilot didn’t know something was badly wrong.
However there have been many cases of people doing a minor prop strike on departure and not discovering it until after they landed. I think that provided you have not actually lost metal, there may not be any obvious vibration.
Counter-rotating props – these must have come off a DA42 L360…
There is no way the pilot didnt’ notice the vibration or power loss.
I think it unlikely that he didn’t notice the collision with the ground either, but maybe it’s possible that he didn’t.
But under times of high stress, people can make unusual choices, and if everything was still running, there would be a lot of temptation to simply touch nothing and take it home. Especially true if home isn’t so far away.
