Hello all,
on 18/10 adamb asked about variable pitch propellors and
alternative engines for the europa. As Ivan Shaw has pointed out some
time ago, the aircraft was designed generally for engines in the 80 to
100 hp range and specifically for the rotax 912, with its generally
accepted reliability and power to weight ratio. Yes it is expensive,
but are comparable engines really that much cheaper ? The subaru is a
little cheaper, but you'll only spend the money saved on some other
gadget in the panel !
The reason for putting bigger engines (ie more horsepower) into
europa's is to generate more power at the prop and thus shorten what is
already an extremely quick take-off run. Outside the UK there are
probably several alternative engines that could be adopted for the
europa, but dont forget that it is being produced in the UK and the
Popular Flying Asociation quite rightly expect that any new engines be
properly fitted and tested, as is the case with the subaru. Also the
factory will have to give some sort of approval, and that will all
take time and cost money. As someone pointed out a couple of weeks ago,
europa's are'nt designed to compete with glasairs and travel at over
200mph, they are designed to lift 2 people and lots of baggage from a
field in Yorkshire,UK, and fly to the south of France in one go
(just;-).
Instead of installing bigger engines , an in-flight variable pitch
prop would enable most of the available horsepower to be generated at
take-off speeds and allow the engine to cruise at reduced revs at a
decent 120/130kt with a bog standard 912. The factory are
investigating some v/p props, but we will probably have to wait a
couple of months for the results. To give some idea of climb
rates/cruise at different prop settings read Don Dykins excellent
little book 'Understanding the aerodynamics of your europa'. The
factory can probably supply them.
Of course, a constant speed prop would be the best, and there just
happens to be a europa in Germany that is just about painted and very
close to flying that has on the front end a superb Hoffman 3 blade
constant speed prop pulling a Rotax 912. It no doubt cost a lot of money,
what with the hydraulic governer as well, but it is down to the individual
to decide where their money goes ! As soon as it flies details will be on
this board.
Hope our planes all fly as straight as Peter Kembers,
chus, dave.
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