FAA's Oversight of United Airlines' Maintenance Practices Is Hindered by Inadequate Inspection Resources, Ineffective Workforce Planning, and Impediments to Accessing Air Carrier Data

Date Issued

Wednesday, February 18, 2026

Submitting OIG

Department of Transportation OIG

Agencies Reviewed/Investigated

Department of Transportation

Components

Federal Aviation Administration

Report Number

AV2026014

Report Description

Our Objective(s)To assess FAA's oversight of United Airlines' maintenance practices. Specifically, we evaluated FAA's actions to address maintenance non-compliances and violations at the air carrier.
Why This AuditUnited Airlines is one of the world's largest commercial air carriers, carrying over 160million passengers annually. Several incidents, including in-flight engine shutdowns and emergency landings, have raised concerns about FAA's oversight of United's maintenance practices. Given these issues, we initiated this audit as part of a continuing series of audits related to FAA's oversight of maintenance and compliance issues in the airline industry.
What We FoundFAA's under-resourced inspections, low Certificate Management Office (CMO)inspector staffing levels, and ineffective workforce planning are insufficient to oversee safety risks.

When the CMO may not be able to conduct inspections onsite due to a lack of resources-such as insufficient staffing numbers or the ability to travel to the inspection site-FAA is conducting inspections virtually and not postponing the inspections in accordance with FAA requirements, which adversely impacts its risk quantification models.
The CMO does not have enough inspectors, which increases workload and staff turnover while reducing FAA's capabilities to inspect United's growing fleet of aircraft.
Continued CMO inspector vacancies have contributed to a loss of institutional knowledge within FAA's United CMO as well as prevented the CMO from completing all its required inspections.

FAA has not addressed all prior safety management system (SMS) oversight recommendations or ensured access to air carrier SMS data.

Five of the recommendations we have made to improve the CMO's oversight of SMS since 2019 remain open.
FAA has not effectively educated inspectors on how to access, obtain, and manage an air carrier's SMS data, which prevents inspectors from adequately assessing an air carrier's SMS and determining root causes of maintenance problems.

RecommendationsWe made 6 recommendations to improve FAA oversight of United's maintenance practices.

Report Type

Audit

Agency Wide

Yes

Number of Recommendations

Questioned Costs

Funds for Better Use

Report updated under NDAA 5274

External Link

https://www.oig.dot.gov/library-item/47141

Open Recommendations

This report has 6 open recommendations.

Recommendation Number	Significant Recommendation	Recommended Questioned Costs	Recommended Funds for Better Use
3	Yes	$0	$0
Reevaluate FAA's Business Staffing Rules so that workload, fleet count based on make/model/series, and aircraft models and series with separate maintenance review board reports are considered in the staffing algorithm for each inspector position.
4	Yes	$0	$0
Require that an independent workplace survey of the FAA United CMO be conducted to determine how inspector fleet assignments and workload distribution are impacting office culture. This should include implementing an action plan to address these needs.
5	Yes	$0	$0
Establish and implement an action plan to address FAA's documented staffing shortages and provide continuous resources to the United CMO that addresses retirement trends, average training time, and staffing turnover for a period longer than 3 years to ensure sufficient oversight.
6	Yes	$0	$0
Develop a strategic plan to provide outreach and education to the entire inspector work force on the protections of Safety Management System (SMS) data once the designation of protection is published in the Federal Registry. This should include education on inspectors' ability to request and review an air carrier's SMS data and records when conducting surveillance and addressing non-compliances.
1	Yes	$0	$0
Develop and implement a policy for FAA personnel to determine when an inspection should be postponed based on the percentage and/or type of questions that cannot be answered. This should include a management control so that FAA personnel with authority to assign inspections use "resources not available" when this threshold is met.
2	Yes	$0	$0
Provide analytical support from FAA's Safety Analysis Branch to CMOs to gather, analyze, and trend data for questions that have been answered "not observable" to support risk-based decision making.