On Apr 23, 3:20*pm, Ventus_a
wrote:
Bill D;813718 Wrote:









On Apr 22, 4:43*pm, Robert Danewid wrote:-
Thanks

My problem is that some one has found a supplement named S1A-77 to the
Flight Manual of a 180 hp PA 18 that says that max glider weigth is 600
kg. Can any one send me or direct me to that supplement.

It does not make sense...... We have been towing gliders 600 kg with PA
18 150/180 since the early 80ies.

Robert-

OK, having nothing else to do this afternoon, I did some research.
The 600kg number suggested a European sourced supplement. *US STC's
would likely be in SAE units.

It appears there is a MOGAS STC issued in Switzerland to Wenger &
Kaufmann for PA-18-180-M and PA-18-150 glider tugs. *In pursuit of the
STC the glider tow performance (takeoff roll, climb rate) was measured
with a 600kg glider in tow. *Since that is the heaviest glider tested,
that became the limit for the STC. *This may or may not the source of
S1A-77 but it shows how it can happen. *There are LOTS of different
STC's for PA-18 around the world.

This is a bit if a diversion but most recent European 2-seaters
specify 600kg (Actually, 600 daN) weak links for aero tow. *If these
gliders are operated in strict compliance with their Approved Flight
Manuals as required by FAR 91.9, 600kg would be the max load on the
tug.

I have been assuming (possibly in error) that you are in the US.

Can't agree that most recent European 2 seaters specify 600kg weaklinks
for aerotow. *The Duo Discus for example is 50% or so higher and the DG
1000 is higher again at 1100 DaN

Having said all that here in New Zealand there are some operations that
use PA-18 180s and they variously tow Duos and ASH 25s so they are well
capable of handling the bigger ships subject to density altitude
considerations

Colin

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--
Ventus_a

From the DG-1000 manual page 2.10: "6000 N + 600 N (1323 lbs. + 132
lbs.) for tow
behind slow tow planes" Which I think would include a PA-18.

The Duo allows a 700 daN weak link but that's not 50% higher.