U.S. Regional carrier PSA Airlines has grounded its entire fleet after a number of the airline's aircraft were found with a mechanical issue. The airline is a wholly-owned subsidiary of American Airlines and flies under the American Eagle brand. The airline operates a fleet of 130 aircraft, composed of CRJ-900 and 700 variants. The grounding comes after an FAA issued AD (airworthiness directive) called for the inspection of the nose landing gear portion of the aircraft. 

The FAA first called for these inspections after reports of excessive corrosion in the nose gear area of the Bombardier Challenger aircraft, the private jet form of the CRJ-900 and 700. After these inspections, there were a number of reports of similar issues in the commercial variant. These reports led to an investigation into whether PSA was complying with the AD and keeping up with proper maintenance. In the AD, the FAA said "The FAA is adopting a new airworthiness directive (AD) for certain Bombardier, Inc., Model BD-100-1A10 airplanes. This AD was prompted by a report that corrosion was found on the shock strut cylinders during unscheduled maintenance of the nose landing gear (NLG). This AD requires a modification of the NLG shock strut cylinder. The FAA is issuing this AD to address the unsafe condition on these products." After further investigation, it was determined that in order for PSA's aircraft to meet the proper safety measures outlined by the FAA, the airline would have to modify parts of the nose gear. 

The unordinary grounding has led to over 120 canceled flights. In a tweet addressing the groundings, the PSA said "Most of our aircraft have temporarily been removed from service to complete a standard inspection. We're working to resolve the issue and sincerely apologize to our customers for the inconvenience." A source has reported that the airline plans to have all aircraft ready to be back to normal operations by tomorrow, as the modifications are planned to be completed overnight.