Having read the detailed analysis, by Jerry Davis (presumably in his
Banbi) I
have to say that I concur with it wholeheartedly.
It is clearly expressed, mathematically based and like most predictions
which
are based on solid aerodynamic principals, it is testable and
repeatable.
I could easily claim my grandmother had lived to 145, and until someone
took the
trouble to visit me and inspect birth and death certificates, no one
would be any wiser.
10 litres/hr at 120 knots TAS in a Europa shaped aeroplane just seems to
break
all the rules. It is just sooo easily to over estimate TAS.
I've said it before, and I'll say it again. IMHO, most unmodified
Europas appear to fly
at around 120 knots TAS and just over 3 1/2 Imp Gal/hr. (with a good
deal of
throttle). Throw in the intangables of head/cross winds, course errors,
climbing
and decending, and control zone avoidance and 110 knots is probably a
good working target for return day trips.
With a very strong headwind on the homeward leg of a long journey I
sometimes have
my work cut out to fly at much over 100mph. (ground speed)
What I've heard about speed kits, VP props, bigger engines and
refinements would
seem to realistically add around 10 knots to this basic cruise. This is
what I would
expect, anyway.
What really concerns me about all the performance hype is that
current/future
builders are being misled into having grossly unrealistic expectations
(as I was !)
of what will be for them, a huge investment in time and money.
Someone, please, under-estimate for a change ....=A3$%
!!!!
Alan. D. Stewart
-----------------------------------------
14 Goddard Way 'phone : +44 1245 264186
Chelmer Village work : +44 1245
275104
Chelmsford, Essex CM2 6UR email :
alan.stewart@blueyonder.co.uk
-----------------------------------------
office email : alan.stewart@marconi.com
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