The Federal Aviation Administration has allowed Southwest Airlines to continue flying Boeing 737-700s for five days until missed maintenance checks are completed. The carrier temporarily grounded 128 of the jets, about one fifth of its fleet, on February 24 after discovering that inspections of the aircraft’s standby hydraulic system were overdue.

“Once identified, Southwest immediately and voluntarily removed the affected aircraft from service, initiated maintenance checks, disclosed the matter to the FAA and developed an action plan to complete all overdue checks,” Southwest said in a statement. The carrier said it cancelled about 80 flights because of the grounding, but it expected minimal further impact.

The FAA in a statement confirmed that Southwest had notified it of the missed inspections on the “standby rudder system” late in the afternoon on February 24. The agency said it worked with Southwest and Boeing “to evaluate a proposal” that would allow the carrier to continue flying the 737s until inspections are completed.