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Old May 19th 15, 12:32 AM
Ventus_a Ventus_a is offline
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First recorded activity by AviationBanter: May 2010
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Quote:
Originally Posted by View Post
On Sunday, May 17, 2015 at 2:43:09 PM UTC+1, Craig Funston wrote:
Slow tow with full water?


I don't know anything about the circumstances but there has been an advisory email to all owners to emphasise the need to make sure that tug pilots are briefed that the minimum aerotow speed for a fully ballasted JS1C/21m is 70 knots (130 km/h) in turbulent conditions. The minimum in calm conditions is 65 knots.

The wingloading of a 21m JS1 at the MAUW of 720Kg is 58.7kg/m2 which is higher than any other glider that is likely to be regularly aerotowed in any numbers. The only other production gliders with similar max wing loadings are the Quintus and the EB29 with its shortest 25.3 tips (which are all self launchers) and the Antares 23T of which there are not likely to be many. It is this unusually high wingloading that needs to be fully appreciated at both ends of the tow rope IMHO.

John Galloway
I've had the experience in my Nimbus 3D of a tow pilot slowing up to try and maintain a positive rate of climb at my home club. Much calling on the radio finally got me some more speed and comfort

I've also had a clubmate recount a tow pilot declaring he was already towing fast enough when he was calling for more speed in his heavily loaded ship while launching at another club.

Both occasions were experienced tow pilots so there was some sort of disconnect going on.

There are 3 JS1s here at the one club in NZ, 2 are JS1-C 18/21 and the other one a B. I must ask of their experiences tow wise when I next visit

Last edited by Ventus_a : May 19th 15 at 12:46 AM.