Accident Overview
On the night of July 9th, an agricultural aircraft was involved in a collision with a caution sign and later with a stack of hay bales during a spray operation. The incident occurred at an airstrip where workers from the Imperial County Irrigation District had erected a large caution sign on the departure runway earlier that day. The sign was placed approximately one-third of the way from the starting point of the runway.
Sequence of Events
The pilot arrived at the airport that night to conduct a spray run. He was unaware that the caution sign had been newly placed on the runway. After loading the chemicals to be sprayed into the aircraft's hopper, the pilot took off. During the takeoff roll, the aircraft struck the sign with its left spray boom. The impact tore the boom loose from the aircraft structure, but it did not completely separate. The loose boom began to flap in the airstream, while chemicals poured from the hopper.
In response, the pilot turned the aircraft to return to the airstrip and reached for the emergency shutoff valve to stop the flow of chemicals. As the aircraft approached the airstrip, it collided with a stack of hay bales that had been recently erected near the runway.
Investigation Findings
The investigation revealed that the caution sign was placed by workers from the Imperial County Irrigation District during the day of July 9th. The pilot was not informed of the sign's presence. The left spray boom was damaged but remained attached, flapping during flight. The emergency shutoff valve was reached for but not stated whether it was activated before the collision with the hay bales.
No information was provided regarding injuries, aircraft damage extent, or specific aircraft type or registration. The investigation did not assign a probable cause.