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Off field landing Hawaii RV-12

From the article:

"About an hour in, flight school officials said the plane “wasn’t acting the way they wanted it to.” They say the pilot made the decision to land on the grass at the naval base in Maili out of an abundance of caution."

So it was a precautionary landing in a grass field due to the pilot's discretion. Good job.
 
I don't know much about Rotax engines. Is it common for the engine to stop with one prop blade straight down like that? Also, is there any kind of inspection or teardown requirement after presumably chewing its way through a bunch of tall grass?
 
Desert Rat said:
I don't know much about Rotax engines. Is it common for the engine to stop with one prop blade straight down like that? Also, is there any kind of inspection or teardown requirement after presumably chewing its way through a bunch of tall grass?
Click to expand...

There is an inspection requirement described for a prop strike. If the engine was not running and there was no damage to the propellor (Rotax describes it as damage to a prop that requires removal to repair) then it's reasonable to think the inspection is not necessary. This decision would require facts that we don't have.

The inspection does not require a complete teardown. The gearbox would be removed and there is a procedure to test the slipper clutch mechanics. From there, you can inspect the crank for runout and twist with no further disassembly. The inspection itself is not a big deal, but if you do have crank damage you're probably replacing the engine.
 
Desert Rat said:
I don't know much about Rotax engines. Is it common for the engine to stop with one prop blade straight down like that? Also, is there any kind of inspection or teardown requirement after presumably chewing its way through a bunch of tall grass?
Click to expand...
The engine has a propeller speed reduction unit (gear box) so the rotational position of the prop relative to cyl compression is constantly changing, so it sometimes stops vertical and sometimes stops horizontal.
 
Maybe not relevant here... moderators can dump this question. I did a flight review with an RV12 builder. The Rotax throttle was spring loaded to full open. You needed to pull back and lock friction to keep it from running wide open.
Man, that just struck me as weird and maybe wrong?
Anyway, a good precautionary landing like this is just good pilot practice. Picking out weeds and grass is far better than picking up dead people.
 
flightlogic said:
Maybe not relevant here... moderators can dump this question. I did a flight review with an RV12 builder. The Rotax throttle was spring loaded to full open. You needed to pull back and lock friction to keep it from running wide open.
Man, that just struck me as weird and maybe wrong?
Anyway, a good precautionary landing like this is just good pilot practice. Picking out weeds and grass is far better than picking up dead people.
Click to expand...
This is standard for any aircraft using a 912 Rotax equipped with carburetors.
 
rvbuilder2002 said:
The engine has a propeller speed reduction unit (gear box) so the rotational position of the prop relative to cyl compression is constantly changing, so it sometimes stops vertical and sometimes stops horizontal.
Click to expand...
Actually... the gearbox has a "hunting" ratio and prop will stop in any position, not just vertical or horizontal.
 
Piper J3 said:
Actually... the gearbox has a "hunting" ratio and prop will stop in any position, not just vertical or horizontal.
Click to expand...
Good to know🙄

I agree that saying the prop. can stop in any position would have been better but if we want to get technical, even that is incorrect. There is a finite number of positions it will likely stop in based on the number of cylinders and the actual gearing ratio 😉
 
flightlogic said:
Maybe not relevant here... moderators can dump this question. I did a flight review with an RV12 builder. The Rotax throttle was spring loaded to full open. You needed to pull back and lock friction to keep it from running wide open.
Man, that just struck me as weird and maybe wrong?
Anyway, a good precautionary landing like this is just good pilot practice. Picking out weeds and grass is far better than picking up dead people.
Click to expand...
I thought this was strange when I first learned about it, but it makes perfect sense. I'm a car you spring load the throttle closed so if something goes wrong you calmly come to a stop on the side of the road. In a plane, going to idle power may be your death if you don't have anywhere to immediately land. Spring loading to full throttle means you can continue flying as long as needed, then kill the engine with the ignition switch when you're in a good position for a power off landing.
 
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