Visible crew/equipment: In the scene where Dan is being attended to by the crew after he has been hit you can clearly see that it is a prosthetic arm that they are holding up and not Dan's.
Visible crew/equipment: During the take-off sequence, in a close-up showing a ground crewman pulling the chock away from the front of a tire, production crew and a van can be glimpsed in the far distance out of focus before being obscured by more period accurate vehicles and extras.
Answer: That would be a flare being fired from the aircraft. Yellow ones meant the aircraft had sustained serious damage, although that was often self-evident, and a red one meant that there was a seriously injured crewman on board - prompting first aid teams to be ready to meet the aircraft once it had landed. Their was also an unofficial green flare that meant someone had completed their tour of duty.
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