MARKERINBOUND
You touched a disk brake on a Three? All I ever had were drums and expander tubes.
They sure looked like disks to me. Mind you it these were two COLPET DC-3s ( in Colombia) sporting uncommon wheel spats that recieved plenty of TLC from company mechanics .. so had ungraded brakes perhaps? else I am wrong.
Still remember the clicking of the hot engine and exhaust metal after shutting down.
That is an amazing list of gasoline grades had no idea! How would you choose when filling up?