What happened
The FAA’s narrative, in sentence case. The FAA writes it in capitals and removes private details.
On September 17, 2022, about 0853 mountain daylight time, a Cessna 172S, and a
Sonex xenos, were destroyed when they were involved in a mid-air accident near
Longmont, Colorado. The flight instructor and student pilot aboard the Cessna and the pilot
Aboard the sonex sustained fatal injuries. The Cessna and sonex airplanes were operated as
Title 14 code of federal regulations part 91 instructional and personal flights, respectively.
A review of air traffic control (ATC) flight track data revealed the Cessna departed rocky
Mountain municipal airport (bjc), denver, Colorado, about 0843, and the sonex departed
Platte valley airpark (18V), hudson, Colorado, about 0838. Both airplanes climbed to about
7,000 Ft mean sea level (MSL) and were operating under visual flight rules (VFR).
The Cessna flew northbound and the sonex flew westbound, both toward the Longmont area.
After completing a left 360° turn, the Cessna turned right toward the east in the direction of
The westbound sonex. The flight track data of the two airplanes merged and subsequently
Showed both airplanes rapidly descending. Fragmented sections of the outboard left wings of
Both airplanes were found below the merged flight track data.
Both airplanes impacted nose down in a rural area with a ground elevation of about 5,100 feet
MSL. The main wreckage site of the Cessna was about 1,800 ft southeast of the wing fragments.
The main wreckage site of the sonex was about 1,100 ft southwest of the wing fragments.
At the time of the accident, both airplanes transmitted a transponder code of 1200 (VFR).
Neither airplane was in radio contract with ATC. The Cessna was equipped with automatic
Dependent surveillance broadcast (ADS-B) “in/out” equipment and was transmitting ADS-B
Data during the accident flight. The sonex did not transmit ADS-B data during the accident
Flight and ATC records indicated the last ADS-B data was transmitted on July 14, 2022.
Both airplanes were retained for further examination.
As the FAA filed it
ON SEPTEMBER 17, 2022, ABOUT 0853 MOUNTAIN DAYLIGHT TIME, A CESSNA 172S, AND A
SONEX XENOS, WERE DESTROYED WHEN THEY WERE INVOLVED IN A MID-AIR ACCIDENT NEAR
LONGMONT, COLORADO. THE FLIGHT INSTRUCTOR AND STUDENT PILOT ABOARD THE CESSNA AND THE PILOT
ABOARD THE SONEX SUSTAINED FATAL INJURIES. THE CESSNA AND SONEX AIRPLANES WERE OPERATED AS
TITLE 14 CODE OF FEDERAL REGULATIONS PART 91 INSTRUCTIONAL AND PERSONAL FLIGHTS, RESPECTIVELY.
A REVIEW OF AIR TRAFFIC CONTROL (ATC) FLIGHT TRACK DATA REVEALED THE CESSNA DEPARTED ROCKY
MOUNTAIN MUNICIPAL AIRPORT (BJC), DENVER, COLORADO, ABOUT 0843, AND THE SONEX DEPARTED
PLATTE VALLEY AIRPARK (18V), HUDSON, COLORADO, ABOUT 0838. BOTH AIRPLANES CLIMBED TO ABOUT
7,000 FT MEAN SEA LEVEL (MSL) AND WERE OPERATING UNDER VISUAL FLIGHT RULES (VFR).
THE CESSNA FLEW NORTHBOUND AND THE SONEX FLEW WESTBOUND, BOTH TOWARD THE LONGMONT AREA.
AFTER COMPLETING A LEFT 360° TURN, THE CESSNA TURNED RIGHT TOWARD THE EAST IN THE DIRECTION OF
THE WESTBOUND SONEX. THE FLIGHT TRACK DATA OF THE TWO AIRPLANES MERGED AND SUBSEQUENTLY
SHOWED BOTH AIRPLANES RAPIDLY DESCENDING. FRAGMENTED SECTIONS OF THE OUTBOARD LEFT WINGS OF
BOTH AIRPLANES WERE FOUND BELOW THE MERGED FLIGHT TRACK DATA.
BOTH AIRPLANES IMPACTED NOSE DOWN IN A RURAL AREA WITH A GROUND ELEVATION OF ABOUT 5,100 FEET
MSL. THE MAIN WRECKAGE SITE OF THE CESSNA WAS ABOUT 1,800 FT SOUTHEAST OF THE WING FRAGMENTS.
THE MAIN WRECKAGE SITE OF THE SONEX WAS ABOUT 1,100 FT SOUTHWEST OF THE WING FRAGMENTS.
AT THE TIME OF THE ACCIDENT, BOTH AIRPLANES TRANSMITTED A TRANSPONDER CODE OF 1200 (VFR).
NEITHER AIRPLANE WAS IN RADIO CONTRACT WITH ATC. THE CESSNA WAS EQUIPPED WITH AUTOMATIC
DEPENDENT SURVEILLANCE BROADCAST (ADS-B) “IN/OUT” EQUIPMENT AND WAS TRANSMITTING ADS-B
DATA DURING THE ACCIDENT FLIGHT. THE SONEX DID NOT TRANSMIT ADS-B DATA DURING THE ACCIDENT
FLIGHT AND ATC RECORDS INDICATED THE LAST ADS-B DATA WAS TRANSMITTED ON JULY 14, 2022.
BOTH AIRPLANES WERE RETAINED FOR FURTHER EXAMINATION.
NTSB investigation
The NTSB’s investigation of this event, with its probable cause and findings. Matched to this report by N-number and date.
Other aircraft in the event · 1
Each aircraft in a collision has its own report.