My actual solution to the difficult U/C retraction was to extend the
retraction lever handle (hand grip) so that you have a much firmer hand
hold, it was surprising just how much that minor mod helped to get over the
problem of loss of aerodynamic help from the flaps. My aircraft has flown
with both short and long wings since conversion with no obvious flap
problems/fouls, but I will have a much closer look next time I change wings.
Ian cook
G-CBHI
-----Original Message-----
From: owner-europa-list-server@matronics.com
[mailto:owner-europa-list-server@matronics.com] On Behalf Of David DeFord
Sent: 08 February 2014 23:46
Subject: RE: Europa-List: Re: Motorglider wings
--> <deford.dave@gmail.com>
> Why would you need to change bungee tension between long and short
> wings as is hinted at from #6?
It isn't necessary to change the tension between long and short wings, but
the difference in retraction/extension force is significant. Particularly
at higher speeds, aerodynamic forces on the flaps push them toward the
retracted position, giving a reduction in retraction force (and an increase
in extension force) toward the "down" end of the cycle. After changing from
short wings to long, I am always surprised for the first few flights that I
have to push forward on the gear lever to start it moving after releasing it
---From the latched-down gate. Of course, the difference in force is minimal
near the fully retracted position. A builder of a dedicated motorglider
might choose to optimize the bungee tension differently from an airplane
with short wings only, but we did not adjust the tension when we added the
long wings to our flying short-wing XS mono.
Dave DeFord
N135TD
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