3 personnel was most common as many ground tasks required 3 personnel per the TO (refueling for instance). On KC-10's there are only two bases that have that airframe so we always flew with a minimum of 2 maintenance personnel and up to 4 dependent on the mission and aircraft configuration.

If going from Travis to Wake Island, then one would accompany. For example, if a 141 was going from Dover to Ramstein, then no FCC needed. Typically, with 141's we only flew if the aircraft was going to destinations that did not have enroute support for that airframe. I was a Flying Crew Chief (FCC) on C-141's and KC-10's. Never happened to me, but we were trained on how and when and where to enter the aircraft. In very rare cases, such as a general alert and launch it was not unheard of for us to have to climb aboard and ride as supernumeraries as the bombers began rolling. Most of the aircrew avoided us as if we had something catchy. For nuclear armed bombers we performed wing tip to wing tip security as well as enforced the no lone zone policies. Gradually enlisted were replaced with officers on the bomber crews. Now when I was providing flight line security to Buff's there were some enlisted crew on those, but their jobs were strictly related to their roles on the aircraft, same with the tanker crews. Don't know what he did when he was not flying but in the air he made sure we were properly belted and stowed and handled the door etc. Those times I was flown, there was always one enlisted crewman at the door. We normally drove to our deployed posts in the missile fields but if weather became an issue or a medical emergency or other security issue arose we could and would be flown into the field. The Air Force, post war, had enlisted crew in choppers.

Reddit bomber crew