CommuteAir Flight 4339 Runway Excursion and NTSB Preliminary Findings

CommuteAir Flight 4339 Runway Excursion: A Breakdown of the NTSB Preliminary Report

On the night of September 24, 2025, CommuteAir flight 4339, operating as a United Express service, ended its journey from Washington Dulles not at the terminal, but in an engineered materials arresting system (EMAS) at Roanoke-Blacksburg Regional Airport (ROA). The Embraer EMB-145XR, carrying 50 passengers and 3 crew members, overran runway 34 during a rainy landing. Fortunately, the incident resulted in no injuries and only minor damage to the aircraft, a testament to the effectiveness of modern runway safety technology. However, the events leading up to this runway excursion, as detailed in the National Transportation Safety Board’s (NTSB) preliminary report, raise important questions about crew coordination, decision-making under pressure, and adapting to rapidly changing weather.

The flight was already under a degree of stress before it even left the ground. It was the second leg of the fourth day of a long rotation for the crew. Passengers had been deplaned twice due to maintenance issues, leading to a departure approximately two and a half hours behind schedule. While pre-flight delays are not uncommon, they can contribute to a cascading series of events. This incident serves as a critical case study for the aviation industry, highlighting the razor-thin margins that separate a routine landing from a serious incident and the layers of safety that are in place to mitigate the consequences when things go wrong.

The NTSB’s investigation is ongoing, and this initial report provides a factual, unvarnished look at the sequence of events. It lays the groundwork for a deeper analysis of operational factors, human performance, and air traffic control communications. As we dissect the available information, we get a clearer picture of the dynamic challenges the flight crew faced and the critical decisions made in the final moments of the flight. The data from the cockpit voice recorder and flight data recorder will be crucial in piecing together the complete narrative.

From Clear Skies to a Rainy Approach

The flight’s journey from Washington to Roanoke began with a weather forecast that suggested a routine arrival. The initial Automatic Terminal Information Service (ATIS) report for ROA indicated calm winds, no rain, and runway 6 in use. Based on this, the captain, who was the pilot flying, briefed for a localizer approach to that runway. The first officer, acting as pilot monitoring, proactively suggested reviewing landing performance for a wet runway, but the captain declined, citing the clear conditions reported by ATIS. This initial interaction sets the stage for a developing situation where crew communication and differing perspectives on risk would become a central theme.

As the aircraft began its descent, the weather picture changed dramatically. Approach control alerted the crew to precipitation near the airport and advised that other aircraft were now using runway 34 for landing. This prompted a change in plan. The captain requested the first officer set up and brief the ILS (Instrument Landing System) approach for runway 34, a more precise approach suitable for deteriorating weather. The crew was now actively adapting to a new set of circumstances, a standard procedure in the dynamic environment of aviation.

The situation continued to evolve rapidly on the final approach. The crew overheard a report from a preceding aircraft that mentioned marginal visibility and bumpy conditions. The rain intensified, leading the first officer to perform a landing calculation for a wet runway. The calculation showed a safety margin of about 200 feet more than required, even without the use of thrust reversers. This data point suggested the landing was feasible, but the conditions were far from the calm, dry scenario anticipated at the start of the flight.

The Final Moments: Go-Around Calls and a Captain’s Decision

The intensity of the rain increased to “heavy” on the short final, prompting the captain to request the windshield wipers be set to high speed. As the aircraft descended below 500 feet, a critical phase of flight, the first officer noted they were high on the precision approach path indicator (PAPI), a visual aid that helps pilots maintain the correct glidepath. A high indication means the aircraft is above the ideal descent profile, which can lead to touching down too far down the runway and not having enough distance to stop.

Recognizing the unstable nature of the approach, the first officer made a critical callout: “go-around.” This is a standard call for discontinuing a landing approach that is not proceeding as planned. The call was made as the aircraft crossed the runway threshold, but the captain continued with the landing. The first officer repeated the “go-around” call about halfway down the runway, but again, the captain continued the landing attempt. This divergence in crew action is a significant point of interest for the NTSB’s human factors investigation.

The NTSB report states, “After crossing the runway markings, the FO called for a go-around, but the captain continued. About halfway down the runway, the FO called for a go-around a second time, but the captain continued.”

After touchdown, the crew applied maximum braking and deployed the engine thrust reversers. Despite these actions, the aircraft could not be stopped on the remaining runway. It overran the pavement and came to a safe stop in the EMAS. The successful deployment and function of the EMAS bed prevented a potentially far more serious outcome, containing the aircraft and protecting everyone on board. Following the event, airport rescue and firefighting personnel boarded the aircraft and assisted passengers in evacuating via a ladder.

The Investigation and the Role of Safety Systems

The NTSB is leading a comprehensive investigation into the incident, with participation from the Federal Aviation Administration (FAA), CommuteAir, the Air Line Pilots Association (ALPA), and Brazilian authorities, as the aircraft was manufactured by Embraer. Specialists in various fields, including flight recorders, meteorology, air traffic control, and human factors, have been assigned to the case. The cockpit voice and flight data recorders were recovered and sent to the NTSB’s lab in Washington, D.C., for detailed analysis. The data from these recorders will provide investigators with precise details about the aircraft’s parameters, crew conversations, and actions throughout the flight.

A key takeaway from this incident is the undeniable success of the Engineered Materials Arresting System (EMAS). This technology, installed at the end of runways where safety areas are limited, is designed to crush under the weight of an aircraft, decelerating it safely. The images from the report show the aircraft’s main landing gear embedded in the EMAS, illustrating exactly how the system is designed to work. This event serves as a powerful, real-world example of how investment in runway safety infrastructure pays dividends by preventing injuries and major aircraft damage.

The investigation will undoubtedly focus heavily on Crew Resource Management (CRM). CRM is the practice of using all available resources, both human and technological, to ensure safe and efficient flight operations. The differing actions of the captain and first officer in the final moments of the landing will be scrutinized. Investigators will seek to understand the decision-making process, communication dynamics, and any potential factors that may have influenced the captain’s choice to continue the landing despite the first officer’s calls to go around. The findings will likely contribute to ongoing training and procedural refinements across the airline industry.

Concluding Thoughts

The runway excursion of CommuteAir flight 4339 is a stark reminder of the complexities of commercial aviation. It underscores how quickly a routine flight can encounter unforeseen challenges, demanding rapid and accurate decision-making from the flight crew. The preliminary NTSB report provides a factual, dispassionate account of the events, laying the groundwork for a thorough investigation that will ultimately aim to enhance aviation safety for everyone.

While the absence of injuries is a relief, the incident highlights critical areas for review, particularly concerning crew coordination in unstabilized approaches and the persistent challenge of landing in rapidly deteriorating weather. The successful outcome, in terms of passenger and crew safety, can be directly attributed to the effectiveness of the EMAS, reinforcing the importance of such safety systems. The final NTSB report will provide the industry with valuable lessons to prevent similar occurrences in the future.

FAQ

Question: What is a runway excursion?
Answer: A runway excursion is an incident where an aircraft veers off or overruns the runway surface. This can occur during takeoff or landing and can be caused by various factors, including unstable approaches, contaminated runways (with water, ice, or snow), mechanical issues, or pilot error.

Question: What is an EMAS?
Answer: EMAS stands for Engineered Materials Arresting System. It is a bed of crushable, energy-absorbing material placed at the end of a runway. When an aircraft overruns the runway, the EMAS collapses under the weight of the aircraft’s tires, safely decelerating it and preventing it from causing more significant damage or injuries.

Question: Why did the first officer call for a “go-around”?
Answer: A “go-around” is a standard procedure where a landing is aborted. Pilots are trained to initiate a go-around if the approach is not “stabilized”, meaning the aircraft is not at the correct speed, descent rate, or on the correct flight path. In this case, the first officer observed the aircraft was too high on the approach path and called for a go-around to discontinue the unstable landing attempt.

Sources

• NTSB Aviation Investigation Preliminary Report DCA25LA339