On 14 helmi, 09:08, Max Kellermann wrote:
Mike wrote:
XCSoar has an artificial horizon? I did not know that.

Yes:

*http://git.xcsoar.org/cgit/master/xc...enderer/Horizo....

The code has been there for many years, but is disabled, the comment
says why. *(Not my opinion/decision, I would not put artificial limits
on technology used by XCSoar)

This code will be reinstated when Johnny (and the rest of the
OpenVario project) finishes his new vario design, which includes a
real AHRS. *The OpenVario project started long before Butterfly
announced their vario, but since it's a spare time project of a few
soaring geeks, it takes a bit longer.

Max

GPS derived "artificial horizon" is not enough to keep your wings
level when IMC. GPS system is very good for checking your bearing when
flying straight and level, better than compass, but to control glider
in choppy IMC requires either gyro (T&B or horizon) or AHRS system. I
do cloudflying with my glider all the time, and believe me it's
something you don't wan't to try out without proper training and
instruments. It's a lot of fun, if sometimes a bit too exciting, BTW.

I'm actually one of those who will get Butterfly vario because of the
AH feature. I believe that cloud flying in contests was last tried at
Vrsac WGC in 1972. It was very bad idea then, as it's now. There was
two pilots who parachuted to safety after IMC collision.