Canada releases details in NTSB-FAA employee midair probe

Investigation focuses on see-and-avoid, ATC collision alerts

August 29, 2012

A controller in the process of radar identifying a Piper Cherokee received a collision alert alarm just before the aircraft collided with a Beechcraft Bonanza May 28, Canada’s Transportation Safety Board said Aug. 22.

The Canadian agency is investigating the collision near Warrenton, Va., which killed the pilot and instructor on board the Bonanza, because it involved employees of the FAA and NTSB. The PA-28-140 Cherokee was registered to an FAA employee; the V35B Bonanza was registered to an NTSB employee. Having found no mechanical malfunctions and that the weather was good VFR at the time of the accident, the board said in an update that it is focusing its investigation on the effectiveness of “see and be seen” and ATC responses to collision alerts between VFR aircraft.

The Cherokee pilot, the sole survivor of the crash, departed Culpeper Regional Airport that afternoon and leveled off at 2,000 feet msl before contacting Potomac Tracon to request ATC services to conduct a practice instrument approach into Warrenton Airport, the Transportation Safety Board said. The controller was radar identifying the Cherokee when the collision occurred, it added; a collision alert alarm sounded in the controller’s console before the aircraft collided.

The Bonanza was flying southbound in a shallow climb at the time of the crash; the Cherokee was headed southeast in level flight. Investigators said a field-of-view analysis is being performed on both aircraft to determine whether either aircraft would have been able to see the other. The board also is investigating “FAA policies and procedures regarding controller responses to collision alerts between VFR aircraft.”