I've begun to study the Hawker Tempest Mk V for fun and I was wondering about something. During the automated start-up sequence, at the very beginning the voltage seems to go from 0 to a normal battery voltage. However, there is no battery switch nor generator switch in the cockpit.. so my question is: what exactly provides this voltage pre-start-up?
The documentation I found explained that the generator was automatic, however I don't know if the aircraft "engine off" power was provided with a ground power unit or with LRUs (Line Replaceable Unit) located in the fuselage like the Spitfire. In the Spitfire, the battery (also called "accumulator") is located in the fuselage and can only be turned on by a ground crew after he installs & connects the battery in its compartment. Is it a similar system for the Tempest, or was a GPU cart used in real life?
I know this has zero incidence in-game, but I was just curious to see if anyone had the answer to that.