Bohli Compass

lauantai 31. lokakuuta 2015 16.16.26 UTC+2 Dan Marotta kirjoitti:
I truly don't know what it's worth, if anything.



I've read that, properly set up, it can be used to fly in clouds.*
I've also read that it was banned in contests in the US for just
that reason.* It would be fun to have as a toy, just like that J-8
attitude indicator that I've had in a box for close to 40 years.

I've flown with Bohli compass and it's main use is same as directional gyro's. When IMC (or VMC, of course) you can straighten your turn to correct heading right away if compass is tilted correctly. With normal Airpath compass procedure inside cloud is to straighten to any direction, wait 15-30 sec to get compass reading, then calculate how many seconds to make 30sec (or 1 min) standard rate turn to correct heading. This takes easily couple of minutes in all. These days any modern GPS gives you track reading at 1 hZ, which makes Bohli compass totally obsolete. You can not fly IMC with only Bohli compass, that has to be some misunderstanding.