Re: [Paparazzi-devel] reply to " Re: How to descent faster? (Austin Jensen)"

[Famille Chateauvieux-Hellwig]

Le vendredi 28 août 2009 23:17:32 chris, vous avez écrit :
> That is exactly what i experienced also so i am trying to find a
> workable solution
> for the plane to handle descent when a thermal is present.
> Actually where i now fly thermals are the normal situation, there is
> nowhere to hide...
> The code does aggressive climb when the altitude error is big but it
> does not compensate
> for a plane that does not want to come down :-)
> Chris
>
>
>
> _______________________________________________
> Paparazzi-devel mailing list
> address@hidden
> http://lists.nongnu.org/mailman/listinfo/paparazzi-devel

Probably the safest way to come down is to stall. Stop the engine and pull the 
rudder 100%. It looks a bit wild, but the model won't accelerate so much that 
it could break. That's the solution I use with 2 axis gliders not having air 
brakes.

If you have yaw control you can engage a tail spin by adding full side rudder.

To recover, just release the controls to 0%, or even push the elevator 100% 
for a second or so. first rengage the IR stabilisation when the GPS speed 
(ideally pitot) is reasonable again. Take into account that recovering from 
the stall will cost you an extra 10-20m altitude.

Martial