Cessna 401 gear up landing.

Typically on a piston engine damage requiring propeller repair is going to require an engine removal and tear down (or at least did when I worked on them), but what is found on said tear down on engine running vs stopped might be the difference between replacing a handful of mandatory at removal parts vs a crankshaft and or case.

It has been a minute since I’ve dealt with this, so I’d have to dig up current service instructions to be 100% accurate, but a number of years ago Lycoming non-geared engines changed from full tear down to mag particle inspection of the gears in the accessory case (crank gear, magneto and one other IIRC), plus crankshaft flange runout.

Continental on the other hand, the propeller flange or pin at the other end were always cracked after a prop strike, so no use trying to change the inspection criteria.

Not my photo:

1756700894582.png
 
It has been a minute since I’ve dealt with this, so I’d have to dig up current service instructions to be 100% accurate, but Lycoming non-geared engines changed from full tear down to mag particle inspection of the gears in the accessory case (crank gear, magneto and one other IIRC), plus crankshaft flange runout.

Continental on the other hand, the propeller flange or pin at the other end were always cracked after a prop strike, so no use trying to change the inspection criteria.

Not my photo:

View attachment 85225
Yeah my info on Lycoming prop strikes is almost 10 years old at this point.

I’ve got a good story about an IPC being in error and the importance of verifying proper fit of the new parts tho!

Also about making sure the guy picking up your engine cores doesn’t run off with them before you get a chance to do alllll the shipping paperwork
 
This is really interesting, it appears that fires during gear up landings do happen:

Absolutely they do happen. This video you posted, the Hawker 600 video above, and more videos out there. Post-gear up landing fires don’t always happen, but they can, and for a variety of reasons.

At the end of the day though, you have some serious friction between asphalt/concrete and thin aluminum skin, that normally has either fuel cell, tank, or bladder just on the other side of the thin aluminum skin. That all wears down quickly on ground slide, and if the slide is long enough, wears through, often including the tanks. With sparks already there from the friction of the slide, introducing fuel to it is going to result in fire.

And all of this is irrespective of whether your engines are running or not, or propellers turning or not, Hence why I like a foam path on a runway for any planned gear up situation just as a bit of mitigation. In the case of this Baron in the video, it was unplanned, so the option wasn’t there.
 
Absolutely they do happen. This video you posted, the Hawker 600 video above, and more videos out there. Post-gear up landing fires don’t always happen, but they can, and for a variety of reasons.

At the end of the day though, you have some serious friction between asphalt/concrete and thin aluminum skin, that normally has either fuel cell, tank, or bladder just on the other side of the thin aluminum skin. That all wears down quickly on ground slide, and if the slide is long enough, wears through, often including the tanks. With sparks already there from the friction of the slide, introducing fuel to it is going to result in fire.

And all of this is irrespective of whether your engines are running or not, or propellers turning or not, Hence why I like a foam path on a runway for any planned gear up situation just as a bit of mitigation. In the case of this Baron in the video, it was unplanned, so the option wasn’t there.
really depends on the structure of the aircraft and where things lie in the touchdown gear up attitude, like wing dihedral in relation to fuel tank location makes a difference
a few months back a commander 112 landed gear up at my GA airport. its attitude left it scraping the nose bowl and grinding the steps down, with some minor scrapes on the flap trailing edges. didnt even scuff a rivet on the belly or wing.
compare that to a 310 that did the same thing a year or two earlier and the nearly the entire belly skin needed replacement
 
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