My first crash

[patowalker]

The root cause appears to be that engine was not "cut" once it had increased to an un-required/in-demanded power setting in excess of what was commanded/required.

I have an ACS keyed ignition switch (Off L R Both Starter) on my VLA, but I sometimes wonder whether it is a safe arrangement. During power checks, unless I am feeling my way through the detents or looking at the key, it is difficult to know if the left, right or both mags are on. There is also the need to ensure the key is not turned too far, to avoid engaging the starter with the engine runnning.

Although this keyed switch is quite common on VLAs, I wonder if the simple red starter button and lever mag switches would not be a better arrangement, especially if the mags need to be cut in a hurry.

[Jan Olieslagers]

the design of the throttle system "bit you on the bum" because you didn't consider the possibility of a failure

Couldn't have worded that any better, thank you indeed!

[patowalker]

Hi Jan,

Have you ascertained if there has been any damage to the engine or gearbox? It seems that a slipper clutch and composite or carbon fibre prop can help avoid damage from a prop strike.

BTW, have you identified your prop. I have a Kiev Prop here and there are no marks or labels on it that identify the manufacturer.

[Jan Olieslagers]

Update:
-) there was NO identification on the prop, neither the hub nor the blades bore any marks whatever. Not even the maker's logo.
-) the reduction gearbox has been opened, and it was assessed by a person I judge competent to be undamaged. We found it is the type prepared to take a prop governor, though it doesn't carry one; and it also has the slipper clutch.

I was a bit surprised to get very prompt and useful replies to my e-mail inquiries at the manufacturer's (they had remained silent on earlier occasions); and they quoted me quite a fair price for the replacement propeller and the parts for the nose leg. So that on Thursday next I will start my old van for almost its last big trip: some 1600 kms to Eger, Hungary.

I'd rather have been flying, though...

[Jan Olieslagers]

Although this keyed switch is quite common on VLAs, I wonder if the simple red starter button and lever mag switches would not be a better arrangement, especially if the mags need to be cut in a hurry.

A fellow club member said the exact opposite, and it makes sense to me: in an emergency, or a situation of grave stress, one falls back into habits and automatons. Most of us have a habit of stopping a (car) engine with the key, and perhaps if my Rotax was to be stopped by turning the keyswitch then that reflex might have come to me. Perhaps even in time. As it was now, there came to me not the slightest impulse to reach for the magneto switches. Not before it was far too late.