NTSB Investigates United Airlines 737 Tail Strike in Las Vegas

The U.S. National Transportation Safety Board (NTSB) has initiated a formal investigation following a tail strike involving a United Airlines Boeing 737 during landing at Las Vegas in July 2025. The agency's decision to open a full inquiry stems from its classification of the occurrence as an 'accident', indicating the aircraft likely sustained substantial damage.

This classification is a critical distinction in aviation safety protocols. According to federal regulation 49 CFR Part 830, an event is defined as an 'accident' if an aircraft sustains 'substantial damage'. This elevates the event beyond a minor 'incident' and mandates a comprehensive investigation by the NTSB. The agency will now deploy a team to gather evidence, interview the flight crew and witnesses, and analyze flight data to determine a probable cause.

The Investigation and Regulatory Framework

The NTSB's role as an independent federal agency is to investigate every civil aviation accident in the United States. Its primary mission is not to assign blame but to identify the root causes of accidents and issue safety recommendations to prevent future occurrences. The investigation into the United Airlines tail strike will follow a meticulous, established process that includes on-site examination, component testing, and detailed analysis of flight recorders.

Under 49 CFR Part 830.2, 'substantial damage' is defined as damage that adversely affects the structural strength, performance, or flight characteristics of the aircraft and would require major repair or replacement of the affected component. For a tail strike, this often involves damage to the aft pressure bulkhead, fuselage skin, and underlying structural formers. An unrepaired or improperly repaired tail strike can have catastrophic consequences, as damage to the pressure bulkhead can lead to explosive decompression at altitude.

Understanding Tail Strikes

A tail strike occurs when the rear section of an aircraft's fuselage makes contact with the runway surface. According to the International Air Transport Association (IATA), these events most commonly happen during the landing phase. Common contributing factors include an unstable approach, excessive pilot input during the landing flare to achieve a smoother touchdown, or a misjudged go-around maneuver.

Modern aircraft are equipped with systems to warn pilots of an impending tail strike, but the dynamics of landing in challenging conditions can sometimes lead to such events. Following any tail strike, maintenance procedures require a thorough inspection for structural damage. The NTSB investigation will likely scrutinize the approach parameters, crew actions, and any potential environmental factors that may have contributed to the Las Vegas event.

Fleet and Operational Context

United Airlines operates one of the largest and most diverse fleets globally. According to ch-aviation data, the carrier's mainline fleet exceeded 1,000 aircraft as of early 2025. The Boeing 737 family is a cornerstone of its domestic and short-haul international network.

As of late 2025, United's 737 fleet includes multiple variants, such as the 737-700, 737-800, 737-900, 737-900ER, 737 MAX 8, and 737 MAX 9. The NTSB's initial report will specify the exact variant involved in the incident. The ubiquity of the 737 in commercial service means that any safety recommendations resulting from this investigation could have wide-reaching implications for airlines and pilots worldwide.

Next Steps in the NTSB Process

Following the initial fact-gathering phase, the NTSB will continue its analysis, which can take 12 to 24 months to complete. The agency will publish a preliminary report within weeks, providing a summary of the known facts. A final report will follow, detailing the full analysis, the board's determination of probable cause, and any formal safety recommendations directed at the Federal Aviation Administration (FAA), the airline, or the aircraft manufacturer. Details of The NTSB Investigative Process outline the structured steps the agency takes to ensure a thorough and impartial review.

Why This Matters

This investigation underscores the rigorous safety oversight governing U.S. air travel. Classifying the event as an accident ensures that the underlying causes are thoroughly examined, providing critical data that can enhance pilot training, operational procedures, and aircraft maintenance protocols. For the broader industry, the findings will offer valuable lessons in mitigating the risks associated with one of aviation's persistent operational hazards.

Trusted commercial aviation news and airline industry reporting are available at flying.flights. For reporting on UAP sightings, investigations, and aviation-related encounters, see the UAPs section at flying.flights/uaps.