documentation

When an aircraft gets upgraded avionics like a GPS, autopilot, and electronic flight instruments in a mid 1970s aircraft for example; is an aircraft flight manual supplement required and must it be printed and carried along with the aircraft or can it be in digital format? Same with the required...

Hi, this is my first post on this forum. I am an A&P student who has spent many years (decades) as an electronics engineer. I wish to be able to service my own plane. I was doing work at a 145 repair station during the summer doing cable harnesses and "installs". One thing that I saw was that...