American Airlines says it has repaired 42 of 48 planes that were pulled aside and inspected because the seats could come loose.
The airline said Friday that all seat repairs on its Boeing 757 airplanes should be done by Saturday.
American canceled 44 flights Friday after it scrapped 50 flights Thursday because of the seat problem. It said no flights had been canceled for Saturday.
Based on the number of canceled flights, the size of the planes, and American's typical occupancy or "load factor" for September, it's likely that about 14,000 passengers were inconvenienced.
American declined to say how many passengers were affected. A spokeswoman said the airline would put them on later flights or give refunds.
"We sincerely apologize to our customers for any inconvenience this may cause with their travel plans," said spokeswoman Andrea Huguely.
American Airlines said crews inspected the planes earlier in the week and thought they had fixed them. Then on Thursday American said it discovered the real reason the seats weren't staying in place — a pin that locks them into the aircraft floor could pop out because of wear and dirt in the floor tracks.
The seats were removed and reinstalled during renovations intended to provide more legroom for some seats, which can then be sold for an extra charge.
American officials said this week that the removal and reinstallation process didn't cause the problem but might have made it appear sooner.
They added that seats are also removed during heavy maintenance overhauls called D-checks, which are performed about every five years, and when carpeting is replaced or wiring installed. The seats are checked for looseness roughly every 6 months when undergoing a so-called B-check, they added.
The seat fiasco comes as American is still trying to recover from widespread delays and flight cancelations in September.