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Old November 1st 09, 10:34 PM posted to rec.aviation.soaring
Andy[_10_]
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Default Front Electric Sustainer

On Nov 1, 7:07*am, Darryl Ramm wrote:
On Nov 1, 4:29*am, Andy wrote:





On Nov 1, 1:49*am, LimaZulu wrote:


First flight of Front Electric Sustainer - FES


http://www.front-electric-sustainer.com


http://www.youtube.com/watch?v=TNOKq6PKIvM


Regards,


Luka Znidarsic


If I read the specs right you can operate at full power for 14.4
minutes over which time you can climb a bit over 4,300 feet. *How's
that compare to other sustainers? *This seems simpler than most other
configurations which is nice.


9B


It would be interestingly they claim level flight for 120km which is
greater distance than a 4,300' climb will normally allow you to glide.
Just plucking numbers out of thin air of 50 knots for optimal climb
and cruise speeds (I expect climb would be slower) and an L/D of 50:1.
You would travel 22 km in the climb and glide 65km for a total of
87km. It would require a L/D 74 to match the straight cruise. The
exact optimal speeds and the profile of the climb as battery power
diminishes likely affects all this.

Looks like nice packaging. I am curious as well what happens to the
forward air cockpit air vent, nose pitot tube, nose tow hook, and
where cooling air for the engine comes from (presumably the nose
hole). At 95% efficiency the 15kW motor will generate 750W.

Darryl


I mis-read the projected climb as 1.5 m/s instead of 1.6. This still
leaves total climb capability a bit over 4,500 feet so the straight
cruise must get more out of the motor than a sawtooth, though I am not
clear why this would be true.

9B