No.1) Fly the plane. No.2)Fly the plane. No.3) Fly the plane
Quite sound advice, but when you are upside down in a ditch with an aircraft on top of you it would be comforting to know that someone has missed you and that help is on the way - it would be disappointing to survive the landing, but die slowly of hypothermia. Even just the word MAYDAY would be enough to get people thinking about who should be talking to them, you don't necessarily need the full 30 second version.
David was a real gentleman and aviation will be all the poorer without him.