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Old March 10th 09, 04:19 PM posted to rec.aviation.soaring
bildan
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Default motorgliders as towplanes

On Mar 10, 9:56*am, Mike the Strike wrote:
I observed a 100HP Lambada equipped with 13m wings being used as a
towplane in the 2000 Worlds in South Africa. *It seemed to perform
very well despite the moderate density altitude. *They were launching
from an asphalt runway and the ground acceleration was slower than
most other towplanes, but once airborne no difference was notable.

The Lambada and similar modern motorgliders are very light (300kg) -
nearly half the weight of the older designs, such as the Grob 109 -
and perform very well.

I have flown a Grob 109 and it had enough trouble getting itself into
the air. *The Lambada also handles a lot better than the older heavy
beasts and is a joy to fly.

Mike


What the Lambada's towing performance at less than 1320 pounds gross
suggests to me is that the US Sport Light Aircraft regulations offer
the possibility of a formidable tug.

The Lambada's aerodynamics are great but 80 - 100 HP is inadequate for
heavy 2-seaters and ballasted singles. 135Hp or so combined with a
propeller optimized for max thrust below 60 knots would make a huge
difference. Aerodynamics doesn't count for much below takeoff speed -
there it's all weight, engine and propeller.