Generator Size for a Shasta Airflyte 2015 (1961 reissue)

It should run it if you use some power management by keeping the other loads to a minimum. The 5000BTU A/C's use about 400 watts continuous and needs 1200-1800 watts surge power to start. You may have to run the generator with ECO-Mode off so the momentary starting current doesn't trip it out on an A/C restart cycle. But that shouldn't be a deal breaker.