Graeme, As others have said it's a bit like having 5 gears on a car rather than
going everywhere in third. Overall performance is transformed. But there is a
further advantage: The constant speed element goes a long way to stop you
overspeeding
the engine, which can be an expensive or even very serious mistake.
If you are distracted when operating at full power and have to descend to avoid
something or are playing about doing unusual attitudes or aerobatics or
whatever,
it isn't difficult to overspeed with a fixed pitch prop, but a CS prop largely
prevents that.
Unless you have glider wings I would not contemplate a feathering prop.
The theoretical advantage of being able to glide a bit further in the event
of an engine failure is for me heavily outweighed by the possibility or indeed
probability that you will end up trying to land with the prop still feathered,
which will substantially increase the ground run. There is a marked difference
in landing withe prop fully coarse compared with fully fine, let alone
feathered,
and I guess it might double the length of field you need to land without
damage.
Regards, David Joyce, G-XSDJ
Sent from my iPad
On 10 Jan 2012, at 17:44, "graeme bird" <graeme@gdbmk.co.uk> wrote:
>
> So, in the shake down flight we were getting 140kts indicated at 5700 @ 2000ft
on a 912ULS but the ASI is reading a bit high. I presume a VP prop would give
a better take off and climb, quieter, maybe faster cruise particularly in
thinner
air. Am I right and which to go for?
> Woodcomp is significantly cheaper and I am told the wood is more absorbent of
vibrations and less stiff.
> Is the CS controller worth having or is manual variable just as good?
> Is it worth being able to feather it?
>
> I intend to fly on my FP warp drive initially but it would suit me to buy the
next prop now if thats the sensible thing to do.
>
> Advice appreciated.
>
> See you all at the dinner.
>
> --------
> Graeme Bird
> G-UMPY
> Mono Classic/XS FWFD 912ULS/Warp drive FP
> Just Test Flying to obtain permit
>
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>
> Read this topic online here:
>
> http://forums.matronics.com/viewtopic.php?p=362946#362946
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