Frontier Airlines Passengers Evacuated After Plane Hit a Person on the Runway During Takeoff at Denver Airport

“We are investigating this incident and gathering more information in coordination with the airport and other safety authorities,” Frontier Airlines said in a statement

A Frontier Airlines jet in 2024.Credit : Kevin Carter/Getty

NEED TO KNOW

On Friday, May 8, a Frontier Airlines plane bound for Los Angeles struck a pedestrian on the runway at Denver International Airport during takeoff
The pilot reported smoke in the cabin and an engine fire, leading to an emergency evacuation of the 231 people on board
“We are deeply saddened by this event,” Frontier Airlines said in a statement, while confirming that an investigation into the incident has been launched

Passengers on a Frontier Airlines plane were forced to evacuate after the aircraft struck a person during takeoff.

On Friday, May 8, Frontier Flight 4345 “struck a pedestrian on the runway” while taking off at Denver International Airport (DEN), Frontier Airlines confirmed in a statement to PEOPLE.

The aircraft had been bound for Los Angeles International Airport (LAX).

“Smoke was reported in the cabin and the pilots aborted takeoff,” the airline said. “Passengers were then safely evacuated via slides as a matter of precaution.” There were 224 passengers and seven crew members on board at the time.

A DEN spokesperson told PEOPLE that the airport “can confirm the pedestrian jumped the perimeter fence and was hit just two minutes later while crossing the runway.”

“The pedestrian is deceased, and is not believed to be an employee of the airport, nor have they been identified,” the spokesperson continued. “The airport has examined the fenceline and found it to be intact.”

Denver International Airport.Getty

In air traffic control audio obtained by ABC 7, the pilot can be heard reporting that a person was struck, as well as the engine fire.

“Tower, Frontier 4345, we’re stopping on the runway. Uh, we just hit somebody … we have an engine fire,” said the pilot, per the outlet. “We have 231 souls on board. There was an individual walking across the runway.”

The pilot then announced his decision to abort the flight, saying, “We’ve got smoke on the aircraft, we’re gonna evacuate on the runway.”

According to the DEN spokesperson, “12 people reported minor injuries, and 5 of these were transported to local hospitals.”

Frontier Airlines told PEOPLE, “We are investigating this incident and gathering more information in coordination with the airport and other safety authorities.

“We are deeply saddened by this event,” the airline added.

The Denver Police Department (DPD) is assisting in an investigation into the incident.

PEOPLE has reached out to the NTSB for comment.

DEN confirmed the incident in a statement to PEOPLE, adding that it occurred late in the evening.

“Frontier Flight 4345 reported striking a pedestrian during takeoff at DEN at approximately 11:19 p.m. on Friday, May 8, 2026. There was a brief engine fire that was promptly extinguished by the Denver Fire Department,” the airport said. “Emergency crews responded to the scene and bussed passengers to the terminal.

“Emergency response and investigation are ongoing,” DEN concluded. “The National Transportation Safety Board (NTSB) has been notified.”

The runway will remain closed amid an ongoing investigation into the incident.

BLACK BOX REPORT COULD CHANGE EVERYTHING 👀 — Investigators reviewing data from the Frontier Airlines Airbus A321 are reportedly focusing on a brief warning sound heard inside the cockpit seconds before the crash 😳

As the investigation into the horrifying runway incident at Denver International Airport intensifies, new details from the aircraft’s black box (flight data recorder and cockpit voice recorder) are drawing intense scrutiny. Investigators are reportedly zeroing in on a brief but distinct warning sound captured in the cockpit just seconds before Frontier Airlines Flight 4345 struck a trespasser on Runway 17L.

The Airbus A321neo was accelerating for takeoff on the evening of May 8, 2026, carrying 224 passengers and 7 crew members bound for Los Angeles when the tragedy unfolded around 11:19 p.m. MT. The unidentified individual had jumped a perimeter fence and walked onto the active runway, leading to a high-speed collision that damaged the right engine and triggered a brief fire.

Listen to released ATC audio: Frontier 4345: “We just hit somebody… we have an engine fire”

The Critical Warning Sound

According to sources close to the investigation, the flight data recorder (FDR) and cockpit voice recorder (CVR) show the crew received a short audio alert — possibly a runway incursion warning or ground proximity system tone — moments before impact. While modern aircraft like the A321 are equipped with advanced systems to detect obstacles, the high acceleration phase (nearing 140 mph) left little time for reaction.

Aviation safety experts note that at takeoff thrust, pilots are hyper-focused on speed, rotation, and engine parameters. Any unexpected warning in those final seconds can be disorienting. The NTSB and FAA are analyzing whether the system provided adequate notice, if the alert was properly acknowledged, and whether airport surface detection systems (like ASDE-X) failed to flag the intruder in time.

This detail could shift the narrative from a simple security breach to questions about technology, procedures, and split-second decision-making under extreme conditions.

What the Pilots Faced

The released air traffic control audio captures the crew’s immediate response with professional calm:

“Tower, Frontier 4345, we’re stopping on the runway. Uh, we just hit somebody… we have an engine fire.”

The pilots executed a rejected takeoff (RTO), brought the heavily loaded jet to a stop, and managed the ensuing smoke and fire. All 231 people on board were evacuated via emergency slides. Twelve sustained minor injuries, primarily during the evacuation.

Passengers described hearing a loud thud or explosion-like sound, followed by rapid smoke filling the cabin and visible flames from the right engine. Some reported seeing disturbing debris near the wing after the incident.

The Trespasser’s Final Minutes

Thermal surveillance video released by authorities shows the individual calmly walking across the wide runway approximately two minutes after breaching the fence. The calm demeanor has led many to speculate this may have been a deliberate act, possibly suicide by plane. The person was struck at high speed and partially ingested by the right engine intake, causing severe damage and the fire.

Denver officials and Transportation Secretary Sean Duffy have emphasized that the individual was a trespasser who deliberately scaled the perimeter fence. Denver International Airport spans over 53 square miles, making rapid response to intrusions extremely challenging once an aircraft is already rolling.

Why the Black Box Findings Matter

The focus on the warning sound could have significant implications:

Technological effectiveness: Did onboard systems (TCAS, GPWS, or runway awareness tools) detect the threat early enough?
Airport surface surveillance: Why didn’t ground radar or cameras trigger a stronger alert to the tower?
Crew procedures: Was there any opportunity to abort earlier, or was the timing simply too tight at takeoff speeds?
Broader industry impact: This rare event may prompt reviews of perimeter security standards and incursion prevention at major U.S. airports.

The NTSB is currently gathering information, with a full preliminary report expected in the coming weeks. They are examining the evacuation process, engine performance, and the security breach itself.

Passenger Trauma and Lingering Questions

Many passengers remain shaken by the ordeal. Some have described hearing what they believed were human remains being spun inside the engine — a graphic detail that has circulated widely online. The combination of smoke, flames, emergency slides, and the knowledge of what caused the incident has left lasting psychological effects on those aboard.

Frontier Airlines has cooperated fully with investigators and expressed condolences while praising the crew’s handling of the emergency.

A Wake-Up Call for Airport Security

This incident, though extremely rare, exposes vulnerabilities even at one of America’s most modern airports. Despite fences, cameras, patrols, and advanced detection systems, a determined individual reached an active runway in under two minutes.

As black box analysis continues, the brief warning sound could become central to understanding whether this was purely a security failure — or if technology and human factors played a larger role in the timing of the collision.

The victim’s identity has not been released. For the passengers and crew of Flight 4345, what began as a routine flight turned into a nightmare that will stay with them forever. For the aviation industry, the data from those recorders may drive important safety improvements to prevent anything similar from happening again.

The full story of those final seconds on Runway 17L is still emerging — and the black box may indeed change everything we thought we knew about this tragedy.