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Old April 8th 04, 07:16 AM
tango4
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"Miguel Lavalle" wrote in message
...
Does anybody know wheter
this conecctions are of the L'Hotellier type?

Regards

Miguel Lavalle
N5SZ


Which ones? The ones on your Jantar or automatic ones?

If you mean automatic ones then things are different to 'traditional'
control runs that use 'l'hottelier' connections.

In the traditional system a series of pushrods and bellcranks transmit stick
movement from stick to surface. In some cases ( ASW20 and Grob elevator ) a
pushrod connects directly to the control surface via a hottelier and ball
joint mounted a small distance from the hinge line. In the wing control
surface connections the in wing pushrods terminated in hotteliers extend
into the fuselage and are connected to ball joints mounted on the belcrank
arms.

In 'Automatic' hook up different arrangments are made to connect things up.
For example: on Schempp elevators a 2 pronged fork, permanently connected to
the control run using bolted and secured connections, plugs into the
elevator surface. My guess is that this is about 99% certain of being done
correctly and without fault. ( I fly Schempp ships and I still DI and check
before every flight ) Some ships (DG's) have an elevator pushrod that
terminates in a 'C' shaped fitting. A roller bearing on the elevator fits
snugly into the open 'C', a reliable automatic hookup but does need
attention at assembly time.

At the wing root you get to play a different game! My Ventus uses two
different systems. The flaps are driven by a rotating 'torque' tube. The bit
in the fuselage is permanently hooked up and as the wing is fitted a very
simple 'dog clutch' connects the flaps to the drive. The Ailerons and brakes
are a devilishly clever system. On the wing root rib a bellcrank is fitted,
one arm connects to a traditional run inside the wing to the control
surface, the other arm, protruding straight out from the root rib, is
terminated in a roller bearing. The roller bearing slides into a funnel
shaped receiver in the fuselage as the wing is fitted. When the wing is in
place the fit between the bearing and the funnel or horn is reduced to zero.
The horn is permanently connected to the control system so 'voila' automatic
hookups.

Could you convert a traditional ship to automatic hookups? I suppose so
given enough time and money. Worth it? Not really. Rather spend a quiet 5
minutes before every flight going over your ship properly and making sure
everything is in order!

Ian