Mid-Air Collision on Approach to Centennial Airport
On the 11th of May 2021, a Cirrus SR-22 and a Swearingen Metroliner collided while on approach to land at Centennial Airport.
Centennial Airport is a busy general aviation airport in Denver, Colorado. Centennial has three asphalt runways: 17L/35R, 17R/35L and 10/28. At the time of the incident, the parallel runways 17L and 17R were in use.
The Swearingen Metroliner is a twin turboprop, popular as a business aircraft. The Metroliner that day, a 43-year-old SA226-TC registration N280KL, was an air charter cargo flight operating as Key Lime Air flight 970. The pilot was the only occupant for the repositioning flight from Salida, Colorado to Centennial Airport.
The Cirrus SR22 is a high tech single engine aircraft which is known for its full aircraft parachute system. The private light aircraft registeration N416DJ, was owned by a local flight school and rental firm. The private pilot had rented the aircraft for a local area flight. The SR22 had two on board, the pilot and one passenger, and were returning to Centennial Airport after an hour’s flight in the Fort Collins area in the foothills of the Rocky Mountains.
The weather was clear and conditions were visual. The Metroliner was inbound from the north and cleared for a straight-in approach to runway 17L, the longest of the runways at Centennial with 10,000 feet (3,048 metres). He was descending through 6,400 feet about three nautical miles north of the runway threshold.
At the same time, the Cirrus SR-22 was coming in from the northwest and speaking on a different ATC frequency. He was cleared for a visual approach to runway 17R, a shorter runway parallel to the first. He was advised to watch for traffic landing on the parallel runway and warned not to veer too far to the east.
The Cirrus SR-22 initiated in a gentle turn towards the south but as he descended through 6,400 feet, he missed the turn onto final, crossing the centrelines of both runway 17R and 17L.
The Tower controller reacted immediately, asking “Cirrus 6 Delta Juliet…Did you overshoot the final? Cirrus 6 Delta Juliet, do you require assistance?”
You can see the two trajectories on this recreation of the ADS-B data from Flightradar24 with the green line of the Cirrus SR22 coming in from the left side while the Metroliner was flying down from the top:
The Cirrus SR-22 appears to have been slightly above the Metroliner and it seems likely that the pilot, having failed to turn onto final, was looking out for the runway. Instead, he flew into the side of the Metroliner.
The pilot of the Metroliner never saw the Cirrus SR-22. Unsure of what had just happened but presumably experiencing a hard yaw to the left, the pilot immediately declared an emergency.
“We had, um looks like the right engine failed so I’m going to continue my landing.”
The pilot of the Cirrus SR-22 obviously also did not see the Metroliner until it was too late, which is a bit more difficult to justify, especially as he’d called that he had the traffic in sight.
A third aircraft, a Cessna 172 whose pilot was flying his first solo, saw the Cirrus deploy its parachute and reported this to ATC, who asked for a more specific location and then made one last call to the aircraft.
“Cirrus 6 Delta Juliet, if you hear this transmission, we have emergency vehicles in your direction.”
The Metroliner continued its approach and landed safely on Runway 17R. After landing, the pilot contacted ATC again.
“Tower, that was a definite mid-air on short final.”
Yes, it sure was.
I’m not sure it had really sunk in though, as when he was asked if he needed assistance, he replied cool as a cucumber.
“I’m going to taxi off here and I think I’ll just park over at Signature. I’m good, though.”
A local resident heard the collision. “I was in the kitchen and I heard a loud firecracker bang. I ran out…. I thought, ‘Is it somebody jumping out of a plane?’ And then I realised the parachute was attached to a plane.”
Another resident ran to the scene expecting the worst and was stunned when saw two men, the pilot and his passenger, in front of the plane, unharmed.
“They were just standing there like they were at a cocktail party.”
Amazingly, no one was injured. The local sheriff apparently said that both pilots should buy lottery tickets immediately.
The pilot of the Cessna 172 who was on his first solo has posted a YouTube video of his conversation with ATC with a map and his photographs taken of the two aircraft once he was on the ground.
I particularly like the first solo t-shirt he was awarded for that flight that he most certainly will never forget.
If you want to hear the full ATC transcript, I recommend VASAviation’s video which includes a written transcript as subtitles:
The NTSB have confirmed that they are investigating and that the preliminary report is expected in the next 14 days.
“We are working to understand how and why these planes collided,” said John Brannen, a Senior Air Safety Investigator from the NTSB’s Central Region office and the Investigator-in-Charge for the accident investigation. “It is so fortunate that no one was injured in this collision.”
They predicted 12 to 14 months for the final report but I have to admit, looking at the data available now, it doesn’t seem like it will take that long to come up with an analysis.