In the scene when the big guy gets hit by the propeller. Blood splatters on the windsreen of the plane. However when Indy gets the girl out of the plane the blood has dissappeared.
Didn't she move from the cockpit to the tailgunner's station? They are at opposite ends of the plane. Blood was on the aft end of the plane (we see the splat on the tail) The cockpit may have been the only way that a civilian would know to egress the plane. So, she moved back up to the cockpit to have Indy get her out. Although, she knew how to use a tailgunner's machinegun awfully well...