Probable cause
The air traffic controller’s failure to properly scan the runway and local area, and their general loss of situational awareness, resulting in a near midair collision. Contributing to the incident was the Cessna 337 pilot's poor decision making when he failed to fly the standard downwind leg distance from the runway and to maintain the standard traffic pattern altitude.
NTSB analysis
Review of the radar data showed that N370SD, a Cessna 337, was on a right downwind for runway 22 at 300 feet when it overflew runway 18, and at the same time Allegiant Air flight 803 (AAY803), an Airbus A319, was at 200 feet departing runway 18. The closest proximity was 100 feet vertically and 369 feet laterally. The crew of AAY803 saw the Cessna 337 and took evasive action by stopping their takeoff climb and maintaining 200 feet, and flew underneath the Cessna 337, which was at 300 feet as the airplane’s paths intersected over the runways.
The local controller did not visually scan all runways and airspace when he instructed the Cessna 337 pilot to enter a right downwind, and again, when he issued a takeoff clearance to the Allegiant Air flight; the lack of fully scanning all runways and airspace resulted in the local controller losing situational awareness of the Cessna 337, and ultimately not ensuring positive control and separation between the Allegiant Air flight and the Cessna 337.
The Cessna 337 pilot’s downwind leg for runway 22 was significantly less than the standard 1/2 to 1 mile defined downwind leg distance from the runway, which placed the Cessna 337 in a closer vicinity to the runway intersections than what was expected. Additionally, the Cessna 337 pilot did not fly a standard traffic pattern altitude, and the local controller did not instruct or advise the pilot that the traffic pattern altitude was 1,000 feet. PIE airport did not have a charted traffic pattern altitude.
Text from the NTSB. Open the NTSB docket for OPS21LA002 for the full record.
Event
- Date
- Apr 29, 2021
- Type
- Incident
- Place
- St Petersburg-Clearwater, Florida
- Nearest airport
- St Pete-Clearwater Intl (PIE)
- Highest injury
- None
- Weather
- Visual (VMC)
- Light
- Day
From the NTSB aviation accident database: N-registered aircraft, events since 2008, data through Oct 28, 2026. The file is published monthly, so the latest weeks are incomplete and recent records can change. The official source is the NTSB aviation investigation search. CheckAero is independent and not affiliated with the NTSB.