Hop-A-Jet pilots Edward Murphy and Ian Hofmann had just 75 seconds between the first indication of trouble with their Bombardier Challenger 604’s GE Aviation CF34-3B engines and crash landing the twinjet on I-75 in Naples, Florida, on Feb, 9, 2024, according to a trove of documents released late on Friday by the NTSB. The first of three master caution warnings—left engine oil pressure—was recorded at 15:09:33 EST, followed by the same warning for the right engine one second later, and an engine warning six seconds later.
It took the crew an additional 20 seconds, at 15:10:05, to realize both engines stopped producing power while the airplane was at about 1,000 feet msl and 122 knots on a shallow intercept angle for the final approach course to Naples Municipal Airport (KAPF). The crew then transmitted to tower, “…lost both engines…emergency…making an emergency landing.” The tower controller acknowledged the call and cleared the airplane to land. While at about 900 feet and 115 knots, the crew replied, “We are cleared to land but we are not going to make the runway…ah…we have lost both engines.”
The twinjet touched down on the southbound lane of I-75 at approximately 15:10:47, when aircraft ADS-B data also ceased. According to a 17-second dashcam video submitted to the NTSB, the airplane initially was in a shallow left turn and then leveled its wings before touchdown, aligned with traffic. It then showed the left main landing gear touching down first in the center of the three lanes and then the right gear touching down in the right lane. Video then shows the airplane continuing through the right-side emergency lane and into the grass shoulder area before hitting a concrete sound barrier. Then the video showed the Challenger obscured by dust, fire, smoke, and debris until the recording ended.
Murphy and Hofman perished in the accident, but the cabin attendant and two passengers escaped with minor injuries. One person on the ground also suffered minor injuries. The air charter—operated under Part 135 by Fort Lauderdale, Florida-based Hop-A-Jet—originated at Ohio State University Airport (KOSU) in Columbus, Ohio, and was a supplemental lift flight for NetJets.
According to interviews with other Hop-A-Jet pilots, Murphy—the accident captain—was recounted as a meticulous planner, with checklist discipline described as “it was just like you're in the flight simulator in CAE with the proper callouts and everything.” First officer Hofmann was portrayed as “a very calm individual” who “was there to participate and be involved and to learn and to be an active member of the crew.”
Hop-A-Jet pilots Edward Murphy and Ian Hofmann had just 75 seconds between the first indication of trouble with their Bombardier Challenger 604’s GE Aviation CF34-3B engines and crash landing the twinjet on I-75 in Naples, Florida, on Feb, 9, 2024, according to a trove of documents released last month by the NTSB. The first of three master caution warnings—left engine oil pressure—was recorded at 15:09:33 EST, followed by the same warning for the right engine one second later, and an engine warning six seconds later.
It took the crew an additional 20 seconds, at 15:10:05, to realize both engines stopped producing power while the airplane was at about 1,000 feet msl and 122 knots on a shallow intercept angle for the final approach course to Naples Municipal Airport (KAPF). The crew then transmitted to tower, “…lost both engines…emergency…making an emergency landing.” The tower controller acknowledged the call and cleared the airplane to land. While at about 900 feet and 115 knots, the crew replied, “We are cleared to land but we are not going to make the runway…ah…we have lost both engines.”
The twinjet touched down on the southbound lane of I-75 at approximately 15:10:47, when aircraft ADS-B data also ceased. According to a 17-second dashcam video submitted to the NTSB, the airplane initially was in a shallow left turn and then leveled its wings before touchdown, aligned with traffic. It then showed the left main landing gear touching down first in the center of the three lanes and then the right gear touching down in the right lane. Video then shows the airplane continuing through the right-side emergency lane and into the grass shoulder area before hitting a concrete sound barrier. Then the video showed the Challenger obscured by dust, fire, smoke, and debris.
Murphy and Hofman perished in the accident, but the cabin attendant and two passengers escaped with minor injuries. One person on the ground also suffered minor injuries. The air charter—operated under Part 135 by Fort Lauderdale, Florida-based Hop-A-Jet—originated at Ohio State University Airport (KOSU) in Columbus, Ohio, and was a supplemental lift flight for NetJets.
According to interviews with other Hop-A-Jet pilots, Murphy—the accident captain—was recounted as a meticulous planner, with checklist discipline described as “it was just like you're in the flight simulator in CAE with the proper callouts and everything.” First officer Hofmann was portrayed as “a very calm individual” who “was there to participate and be involved and to learn and to be an active member of the crew.”
The docket further detailed the harrowing escape of flight attendant Sydney Ann Bosmans and passengers Aaron Baker and Audra Green. Bosmans’ last-minute seat change and her knowledge of how to open the luggage hatch, despite no formal training on how to do so, may have saved lives after the crash.
According to the flight attendant’s interview with investigators, she made a critical choice in the final moments of flight: rather than remaining in the forward-facing jump seat behind the pilots, Bosmans assessed the situation and then moved to the aft-facing seat in the left forward cabin.
Bosmans, who had been trained through Aircare International’s FACTS program, recalled following training protocol as best she could, citing it as a factor in her decision to move. She knew that she’d be in a better position to brace and then to assess conditions outside the aircraft on the ground.
After moving, she instructed the two passengers to brace, grabbing their ankles and positioning their heads correctly while keeping them as calm as possible. She described the impact as “like a slow-motion movie...shit was just flying everywhere,” and the cabin quickly filled with smoke and “neon flames.”
After the impact, Bosmans moved first to the forward cabin door, but was unable to open it. Acutely aware of the danger of smoke inhalation as well as the threat of fire, she quickly turned to the overwing exit, where the interior panel had already been removed. Bosmans was unable to open that door either, later noting, “The flames were actually coming up on that side...it probably would have been a lot worse if I got that door open.”
That left one remaining option: the baggage compartment door at the rear of the aircraft. Bosmans headed aft, where she found passenger Green asking for help and Baker already attempting to access the area. “He was kind of leaning out the baggage door, so I’m assuming that he was trying to get out that way already,” she said.
In near-complete darkness and with thick smoke filling the cabin, Bosmans attempted to operate the internal latch on the door. “I grabbed the lever on the door... pulled it inward... and I can’t get it,” she recalled. “This door is blocked and stuck.”
With the compartment cluttered by luggage and no flashlight available, she coordinated with Baker and Green to remove obstacles. “I started handing Aaron stuff, and I’m assuming he was handing Audra the stuff as well.”
Then came a sound she couldn’t explain. “I heard like a bang on the door...it’s super close to my face where I’m at. And I truly thought in that moment that there was another person on the other side of the door...obviously, there was no one there, but at the time, like, that’s what I truly believed, and it kind of gave me that…I know I can get this door open.”
She continued handing items back until she was able to clear enough space to open the hatch. Bosmans recalled that she was first to exit, with flames “coming underneath [her] butt.” After a delay in which she thought they might be retrieving belongings, the passengers followed, and Bosmans urged them to stay together and move away from the wreckage.
Bosmans had not received formal training on the use of the baggage compartment door. “We don’t get trained to open the baggage door. I actually just knew how to do that...I would kind of do it as a favor to the pilots,” she told investigators.
On the mechanical side, meanwhile, the NTSB has documented a hung start problem in the engines of the accident Challenger 604 based on an interview with Hop-A-Jet pilot Anthony Donato, who is also an A&P mechanic with inspection authorization, and analysis of historical data,
A preliminary report confirmed the flight crew reported low oil pressure before the dual engine failure. According to the NTSB docket, 25 days prior to the accident, “a series of hung engine starts were recorded by the FDR [flight data recorder]. There were 10 hung starts in total between the two engines, with one successful start on engine 1 occurring during these start attempts.”
The NTSB explained, “A hung start, also known as a hot start or stagnated start, is defined as a start attempt that experiences a light off but does not then successfully continue to a self-sustaining idle speed before engine ITT [interstage turbine temperature] exceeds the start redline. Hung starts may be caused by a variety of factors, including weak starter performance, premature starter deactivation, a degraded or damaged compressor, incorrect scheduling of bleeds or compressor variable geometry, or bad fuel.”
In comparing the hung starts to the FDR data from the accident, the NTSB wrote, “the engines’ fuel and ITT behavior during the event flight was consistent with the behavior of the engines during the hung start rollbacks.”
During the interview with NTSB investigators, Donato summarized his experiences with hung starts in the Challenger, saying he believed it “was an extremely abnormal issue. Out of the 12,000-plus hours in the Challengers [that he had logged], from time to time, you might get a hung start. By the time you go back, the other one starts up. This here was…the right engine would never start after, I don’t know how many attempts, and the left engine, it took, oh, gosh, I don’t know, three, four attempts.
“Finally, it got started and…we’re thinking, all right, maybe it’s a bleed issue, so let’s try to do a cross-bleed with the operating engine…we still couldn’t get the right engine going. So that was a telltale sign to me, as a mechanic, saying this is extremely abnormal.”