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Old January 8th 06, 03:27 AM posted to rec.aviation.soaring
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Default So you think you have a low glide ratio!

In article cR_vf.8501$V.4724@fed1read04,
"BTIZ" wrote:

I think that just has to be a typo... most training Cezzna's are about 7 to
1.
But it would be hard to believe the Pc-12 could get 27/1... I'd believe
maybe 10 or 12 to 1.

3/1 is not much better than a brick. (1/1)


Thatlooks like a sin == tan error. Lift is the component of
aerodynamic force that is perpendicular to the relative airflow, not the
component that is vertically upward. The L/D of a brick is not 1:1 --
which would imply it could fly at an angle of descent of 45 degrees --
but very close to zero.

Well, ok, a canonball has an L/D of zero, if it is not spinning. A
brick would have a slightly better L/D, if you could stabilize it,
perhaps by spinning it, as with a ruler or business card which appear to
have L/Ds of about 1 in stabilized backward-tumbling flight. Maybe a
brick could do that too, at sufficiently high speed?

--
Bruce | 41.1670S | \ spoken | -+-
Hoult | 174.8263E | /\ here. | ----------O----------