Interesting. I can't find any sort of artificial horizon, but i suspect the two "spirit levels" at the bottom (T shape) serve much the same purpose. Given that

Interesting. I can't find any sort of artificial horizon, but i suspect the two "spirit levels" at the bottom (T shape) serve much the same purpose. Given that it was an ocean crossing he would probably be watching the airspeed, altimeter and compass for most of the journey anyways (instrument flight rules?).