It can carry with ease around 50 people, with a minimal crew of one with I.A. in assitance.
-1 flight captain (and master of the bombing)
-2 control logistic personal members (and gunners)
-4 other logistic crew members (and gunners)
-1 informatic and information crew member
-1 Dart pilot
-1 or 2 toilet seats (who can appreciate this at least).
The Ptera can be loaded and carry great amount of bombs. One large rear trap door can be use for other purposes, like carrying a Dart fighter, or for a large retractable gun.
The Dart, smallest fighter in use by the MUHS during the 42th century, is 5.9 meters long.
So, even if it is a very large vehicle, it's great stability and manoeuvrability allow it to take off verticaly. A hexagonal hangar is usually the best place to landed those big birds.