Hi Graham,
That is an interesting observation. I must be missing
some critical aspect of the physics involved in the difference between the
two props and their hubs. In order to airstart an engine, the prop must be
taken out of feather in order for the relative wind to impart a rotational
force. Is it a matter of degree of prop pitch? What am I missing?
Ira
On 3/20/02 4:15 PM, "Graham Singleton" <grasingleton@avnet.co.uk> wrote:
>> Then John told me that several
>> people had hypothesized that the Rotax would be difficult to air start, so
>> of course we just had to try it! After feathering and stopping the prop at
>> about 75 mph, we glided for a short while, with a ratio of about 15:1
>> (short wings this trip), then took the prop out of feather and nosed over a
>> bit. At 110 mph the prop took a few quarter turn jumps. At 120 mph, with a
>> single half rotation, the engine caught immediately.
>
> Teh Rotax is not difficult to air start with a feathering prop, which is
> not allowed in UK I believe.
>
> It is impossible to air start with a fixed pitch Warp Drive prop in a Europa.
>
> Graham
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