Around 1976 or 1977, UA went on a long strike. Afterward, they needed a gimmick to get people flying again. The flight attendants began passing out certificates to the passengers. Each one was good for a roundtrip domestic flight at 50% off. (Back then there were basically only two fares...coach and first class.)

I can remember scheduling trips mainly for the purpose of collecting them. I even bought some off of infrequent flyers who didn't want them. The thought of being able to fly roundtrip first class ORD-LAS for under $200.00 (instead of almost $400.00) was very hard to pass up.

I remember Randy Peterson once referring to this promotion as the true start of the FF programs.