What happened
Two aircraft, N3930E and N3968E, departed together as a flight of two for the purpose of aerial application. There was no record of a preflight briefing or coordination planning between the pilots prior to departure.
At the completion of operations on the object field, N3930E advised N3968E by radio that he was making a final cleanup swath run toward the north along the west boundary of the field. During this swath run, the pilot of N3930E observed N3968E headed southbound and to the east of his position.
On completion of the run, N3930E pulled up, turned right, and began a descent to make an eastbound cleanup run along the north boundary. No radio advisory was issued for this maneuver. The two aircraft collided head-on, left wing to left wing, separating the left outboard wing panels. Both aircraft rolled left into subsequent uncontrolled collision with terrain.
The investigation
The investigation focused on the operational coordination between the two aircraft during the aerial application mission. Investigators noted the absence of a preflight briefing or coordination planning. The sequence of events indicated that N3930E failed to communicate his intended flight path change to the other aircraft in the pair.
Findings
The primary contributing factor was the lack of communication and coordination between the two pilots. N3930E did not advise N3968E of his intention to turn right and descend for a new run, leading to a head-on collision. The absence of a preflight briefing further exacerbated the situation, as neither pilot had established a clear plan for mutual awareness during the final cleanup runs.
Safety message
Pilots conducting aerial application operations should ensure thorough preflight briefings and continuous communication regarding flight paths and maneuvers. Coordination is critical to avoid mid-air collisions, especially during complex or repetitive tasks such as cleanup runs.