Southwest can use planes that missed inspections but checks must be done within 5 days

Federal officials will let Southwest Airlines keep flying planes that missed a required inspection of a backup rudder system.

The Federal Aviation Administration says the inspections have to be done in the next five days, however.

Southwest grounded 128 planes — about one-fifth of its fleet — on Tuesday after discovering the missed inspections.

A Southwest spokeswoman says the airline canceled about 80 flights Tuesday and expects to cancel up to 19 more on Wednesday while some inspections are done.