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Audit Reports


FAA Needs To Improve Its Oversight To Address Maintenance Issues Impacting Safety at Allegiant Air

Requested By
Requested by Representatives Peter DeFazio, Rick Larsen, Nita Lowey, David Price, Mike Quigley, Katherine Clark, Pete Aguilar, Cheri Bustos, and Senators Jacky Rosen and Bill Nelson
Project ID
File Attachment
What We Looked At
Allegiant Air—the Nation’s 11th largest passenger airline—grew faster than the airline industry as a whole in 2018 by carrying approximately 14 million passengers. However, incidents at this air carrier—including a series of in-flight engine shutdowns, aborted takeoffs, and unscheduled landings—have raised concerns about its maintenance practices.
FAA uses its Compliance Program to achieve rapid compliance with regulatory standards, eliminate safety risks, and ensure positive and permanent changes that benefit the aviation industry. This program is based on the concept that the greatest safety risk comes from an operator who is “unwilling or unable” to comply with rules, rather than a specific event or its outcome.
Our objective was to assess FAA’s processes for investigating improper maintenance practices at Allegiant Air. Specifically, we assessed FAA’s (1) oversight of longstanding maintenance issues impacting safety at Allegiant Air and (2) process for ensuring Allegiant Air implemented effective corrective actions to address the root causes of maintenance problems.
What We Found
Since 2011, FAA inspectors have not consistently documented risks associated with 36 Allegiant Air in-flight engine shutdowns for its MD-80 fleet or correctly assessed the root cause of maintenance issues. This was because inspectors did not follow FAA’s inspector guidance that requires them to document changes in their oversight once they have identified areas of increased risk. Also, FAA’s Compliance Program and inspector guidance do not include key factors related to carriers’ violations of Federal regulations. Specifically, they do not contain provisions for inspectors to consider the severity of outcomes when deciding what action to take following a non-compliance. As a result, FAA is missing opportunities to address maintenance issues and mitigate safety risks in a timely manner.
Our Recommendations
We made nine recommendations to improve the effectiveness of FAA’s oversight of air carrier maintenance programs. FAA concurred with eight of our nine recommendations and partially concurred with one. We consider the eight recommendations resolved but open, pending completion of planned actions. We are asking FAA to reconsider its actions for the partially-concurred recommendation.


Closed on
No. 1 to FAA
Develop and implement a management control to require managers to review and validate that known risks documented in the Safety Assurance System Certificate Holder Assessment Tool are tracked until mitigated.
Closed on
No. 2 to FAA
Develop and implement policies and procedures to monitor inspector compliance with Safety Assurance System training requirements.
Closed on
No. 3 to FAA
Revise its inspector guidance to require Certificate Holder Evaluation Process teams to report inspection results to the local inspection office, including a determination on whether the carrier is operating at the highest possible degree of safety in the public interest and how the team reached that conclusion.
Closed on
No. 4 to FAA
Revise its Compliance and Enforcement guidance and its Inspector guidance to include the severity of outcomes as a factor in considering whether inspectors should initiate compliance or enforcement actions.
Closed on
No. 5 to FAA
Develop and implement a resolution process to ensure disagreements in handling non-compliances are dealt with consistently, using the most appropriate processes and all relevant information.
Closed on
No. 6 to FAA
Revise its inspector guidance to clarify how inspectors address recurring non-compliances as a factor in considering whether they should initiate compliance or enforcement actions.
Closed on
No. 7 to FAA
Revise its inspector guidance to require inspectors to determine that corrective actions taken by air carriers are implemented and have addressed known discrepancies prior to closing compliance actions. 
No. 8 to FAA
Perform a comprehensive review of FAA's root cause analysis training to ensure it meets Agency expectations. Modify training, as appropriate, based on the review and require inspectors to complete the course(s) or offer inspectors access to industry-based training programs.
Closed on
No. 9 to FAA
Develop and implement a process to incorporate historical compliance actions in SAS for inspectors to track current and historical compliance actions.