Most Pan Am flights to Europe were night flights not day-time flights. Passengers had dinner, a movie was shown afterwards, the stewardesses pulled down the movie screen from above, and breakfast was served in the morning about 1 or 2 hours before landing.
When Kate and Bridget go into the church - they're obviously both Catholic, as they genuflect and make the sign of the cross - neither's head is covered. NO woman in the '60's would go into a Catholic church without some covering on their head, even a tissue, if nothing else were available. It simply was not done.