Darick,

 

Clever idea, doing the measurement like that.  It could give a useable
number.

 

Was that all at idle power?  A confounding factor is that turns use energy
and the steepness and radius of the turns determines how much energy is lost
in the turn.

 

However, that 8.5:1 ratio sounds like the ballpark glide ratio for the
Coupe.

 

The only really careful and accurate glide ratio testing I've heard of in
the last 30 years was mine and it was all bollixed up due to the airspeed
indicator I didn't know was faulty.

 

The numbers I got were in that range too (after making guestimate
adjustments for the ASI error), perhaps, better at a bit higher airspeeds.

 

Your estimate of 8.5:1 is consistent with my best guess for glide ratio for
around 70-80 mph.

 

If someone would like to do rigorous glide ratio testing, here is a pretty
good procedure - the old fashioned way.  It's kind of tedious, but that's
what's needed for rigorous testing of something like glide ratio.

http://edburkhead.com/Ercoupe/performance_information.htm click on glide
ratio testing.

 

Some new electronic instruments will give a continuous readout of glide
ratio based on altitude, temperature, indicated airspeed and altitude.  My
Stratomaster Extreme instrument package claims that ability but it'll be in
my Challenger if I ever get that finished.

 

For that matter, my Garmin GPS will also give a glide ratio readout.  I bet
many other good GPS units will do that, too.

 

Hope several of you do some testing at various airspeeds and report the
details (including details of your plane and its special drag features
[venturi, landing gear fairings, landing gear mounted landing lights,
etc.]).

 

Hummmmm, the idea of doing this testing with a glide ratio readout GPS
really sounds tempting.  Go, people, Go!

 

Ed

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