Frontier Airlines flight 4345 aborted its nighttime takeoff at Denver International Airport after striking a man who had run onto Runway 17L. The Denver Medical Examiner identified the man as 41-year-old Michael Mott and ruled his death a suicide from multiple blunt and sharp force injuries. The impact sparked a brief engine fire and filled the cabin with smoke as 231 people evacuated on slides. Air traffic control recordings captured the captain’s report from the runway: “Tower, Frontier 4345, we’re stopping on the runway. Uh, we just hit somebody… we have an engine fire,” according to CBS News.
The Airbus A321neo, bound for Los Angeles around 11:19 p.m. MT on May 8, halted on the runway after the collision as firefighters extinguished flames on the right engine. All 224 passengers and seven crew evacuated by slide as a precaution, with 12 people reporting minor injuries and five transported to local hospitals. Inside the cabin, passengers described thick smoke, loud bangs and sparks, and a chaotic rush to exit. Some said they struggled to breathe and were rattled by the scene as the aircraft stood dark on the runway amid flashing emergency lights.
Limbs on the runway
Investigators said Mott climbed an approximately 8-foot perimeter fence topped with barbed wire at 11:13 p.m. and reached the runway in roughly two minutes. Airport officials said it took about 15 seconds to scale the barrier. The aircraft was accelerating at roughly 139 mph when the collision occurred. The runway where it happened sits in a remote area about 2 miles from the terminal. Airport video reviewed by authorities shows a figure walking toward the runway, stepping onto it, and seconds later being struck by the plane’s right engine, which bursts into flame. Investigators said Mott was at least partially drawn into the engine. Controllers are heard noting “limbs on the runway” and a deceased person as emergency vehicles moved in. Security systems on the airport’s eastern perimeter had triggered at about 11:10 p.m., but initial camera reviews showed a herd of deer outside the fence and the view alternated between wildlife and the intruder; with ditches obscuring sight lines, the alarm was mistakenly attributed to animals, according to NBC News.
The airport spans 53 square miles and is ringed by 36 miles of perimeter fencing. Security officers and Denver police regularly patrol the airfield, and officials said operations staff continuously inspect the fence line. Between 2004 and 2015, eight people breached the fence. Security specialists note that most U.S. airport fences, typically 6 to 8 feet (1.8 to 2.4 meters) high with barbed wire, meet federal standards but are not designed to stop determined intruders, and that perimeter breaches by trespassers occur nationwide dozens of times annually. Denver’s CEO said the airport has had fence jumpers before and that even taller barriers may not deter a motivated person. Federal officials notified the airport about the trespasser minutes after the fence was climbed, but the location’s remoteness and the tight timeline left personnel unable to intervene before the plane reached takeoff speed. Authorities also said they found no vehicle nearby and still do not know how Mott traveled to the fence line.
A major security breach
Officials said Mott left no note at the scene and none of his belongings have been recovered. Police records show he had more than 20 prior arrests dating to age 17, including on charges such as DUI, trespassing, resisting arrest, assault, burglary, hit-and-run, attempted murder, and escaping custody. He had previous encounters with Denver and metro-area law enforcement. Transportation officials called the case a major security breach.