This reminds me of when I was in college(EE) and working at an electronics store. A small aircraft owner wanted help with a regulator to (IIRC) drop 28v down t

This reminds me of when I was in college(EE) and working at an electronics store. A small aircraft owner wanted help with a regulator to (IIRC) drop 28v down to 12v and handle a few amps. I resisted helping design a solution but he kept pushing so I suggested putting a couple TO-3 packaged 7812s in parallel. We bench tested it and it worked so he went on his way. A few years later I learned you never do that as one regulator can end up handling the load and it ends up overloaded. Instead you use a pass-transistor(or other mechanism) to allow a single regulator to do the job. I still wonder if that guy's plane ended up going down in flames...