> Hi! Pete
> I must confess I expected the six cylinder to be
> free of this problem but when you stop and think
> it's quite obvious that a geared installation
> wouldn't suffer this problem or at least not
> directly .
> Regards
> Bobn Harrison G-PTAG
> PS. Perhaps Tony K needen't be so shy and advise
> the forum which of the other CS props had a
> similar problem? Come on Tony it's technical
> info that we all need to know and of a safety
> nature not knocking the competition.
Let's call it potential safety, Bob, as for perspective there's no
problem yet indicated in U.S. accident stats. For years 98-00, there
were 207 accidents (in homebuilt fixed-wing, powered airplanes) due to
mechanical failure, 16 due to prop failure. Nine involved auto
conversions or 2-strokes, ranging from failures of drive belt,
redrive, bolts, or crankshaft. The other 7 were real A/C engines.
Six Lycoming/Continental incidents re prop installation/maintenance
issues. The other a 912, where on a pusher config, an exhaust pipe
departed through the prop arc, a likely maintenance issue. Occurred
at cruise, and 2 of 3 composite blades departed, no engine damage,
minor injuries on forced landing. The 912 drive case/crank flange
appear rather rugged?
Conversely, no reported accidents 98-00 involving prop/redrive
problems on Rotax 91X, on hence a thousand+ flying examples here of
the engine/prop combos we're installing.
And before someone asks, only two even possible 91X failures this
period, but no apparent mechanical reason, one in circumstances
suggesting mere stall/spin.
Regards,
Fred F.
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