At 00:24 01 November 2004, John Giddy wrote:
........
Stefan,
Have they done any tests at high altitude airfields
? My memory of
Swiss gliding fields is that they are in valleys, with
reasonably low
altitude. If I am wrong, please correct me, as my knowledge
is
fragmentary regarding your lovely country.
We have discussed ultralight tow planes, but the consesus
seems to be
that with high temperatures (40 C is not at all uncommon)
the high
density altitude will reduce the performance to an
unacceptable level.
I have also heard some rumours that the high speed
Rotax engines don't
take kindly to the extended full power operation necessary
when
towing, and the lifetime is shortened. Can you comment
on this please
?
Cheers, John G. (Victoria, Australia)


John,
talk to the South African guys here. At Gariep Dam
they use a Samba (Rotax engined microlight) for towing
and that is 4000+ft and hot.
http://www.gariepgliding.com/airfield_data.htm#space
http://aeroklubuo.macroware.cz/Lambadaen.html