"Steven P. McNicoll" writes:

You are supposed to be flying at your planned altitude. I don't know
how far ATC would be willing to trust that, though -- you'd certainly
be within your rights to choose a different altitude to avoid
turbulence or icing.

Where are those rights found?

Emergency authority of the pilot (sorry, I left out the adjective
"severe" before "turbulence"). If I'm flying in IMC and go NORDO,
then hit icing or severe turbulence, I'm not going to worry about
sticking with my flight-plan altitude.

I don't claim that it would be OK for the pilot to change altitude
just to avoid light or moderate chop.


All the best,


David