Batteries are great when they have charge. What happens if the generator doesn't want to start the first, second, and third time? How many start attempts do you get before the batteries are dead?
The hand-pumped air compressor is the tool of last resort. You can try an engine start if there's someone there who's able to pump it. You don't have to worry about how much charge is left in your batteries or whether or not the gasoline for the 2-stroke pump engine has gone stale. It's the tool that you use as an alternative to "well, the batteries are dead too, guess we're not going to start the engine tonight... let's call the helicopters and abandon ship"
The hand-pumped air compressor is the tool of last resort. You can try an engine start if there's someone there who's able to pump it. You don't have to worry about how much charge is left in your batteries or whether or not the gasoline for the 2-stroke pump engine has gone stale. It's the tool that you use as an alternative to "well, the batteries are dead too, guess we're not going to start the engine tonight... let's call the helicopters and abandon ship"