Carl Pattinson wrote:
>I believe the Fuel Flow meterb that several people have referred to is actually
>the Benwick Fuel Computer, made somewhere in Cambridgeshire. <snip>
The
>maximum fuel flow that I recorded on the Rotax 447 engine was 25 litres per
>hour
>(about 5.5 gals PH) with no signs of the mixture leaning off. Although a 447 is
>considerably smaller than the 912 we propose to use, fuel consumption would not
>be dissimilar as two strokes are much less efficient than 4
strokes. <snip>
Are you sure your 25 litres / hr is actually what you are using?
It seems inordinately high. I managed to consistently achieve a
true 23 litres / hr with a 462 in speed comps @ 7000 rpm (ie rather
finely pitched, asking for trouble, but never a problem!) but if I
managed 25 l/hr on a 447 in normal flying I would be seriously
worried! With a 447 I would expect at most 18 l/hr @ 6500
continuous. As far as the 912 is concerned I would expect to see 8
- 10 l/hr flying slowly rising to a maximum of 15 or so.
What is the experience of those flying now?
Having used flow meters a lot over the years, besides ensuring the
sensor offers no restriction at max flow it is just as important
that it is still accurate at min flow. We have had a lot of
problems getting decent readings in Microlight economy events where
with the right kit one can achieve as little as 3 l/hr (less if
thermalling) Exceptional I know, but the principle still applies.
Regards
-------------------------------------------------------
Richard Meredith-Hardy TEL + 44 (0)1462 834776
rmh@flymicro.win-uk.net FAX + 44 (0)1462 732668
CIS: 100071,2422
Check out the British Microlight Aircraft Association at
http://www.avnet.co.uk/bmaa/bmaa.htm
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