Casualties unknown

2007-06-01: Christen Industries A-1 (N9602R) — United States Department OF Agriculture — Loa, UT

Loa, UT, US

On June 1, 2007, a Christen Industries A-1 (registration N9602R) operated by United States Department OF Agriculture was involved in an aviation accident near Loa, UT. Investigators recorded the probable cause as: The pilot's failure to maintain an adequate airspeed during low altitude maneuvering flight that resulted in a stall. This summary draws on records from the U.S. National Transportation Safety Board (NTSB) historical archive.

Sourcesthe U.S. National Transportation Safety Board (NTSB) historical archivePrimary reportUpdated 1781061362Data APIEditorial standards

During a low-level predatory control operation, an airplane impacted terrain while maneuvering at slow airspeed. The aircraft came to rest inverted; weight and balance calculations showed it was out of aft CG limits.

Accident Overview

A pilot and gunner were conducting a low-level aerial predatory control operation over terrain at approximately 8,300 feet above mean sea level. While maneuvering in a turn at slow airspeed to make an additional pass over an area where coyotes were present, the airplane struck the ground with its right wing tip. The aircraft subsequently came to rest inverted.

Flight Details

The flight was part of a predator management mission. The aircraft was operating at low altitude, and the maneuver involved a turn at reduced speed. No preimpact mechanical anomalies were discovered, indicating that the airframe and engine were functioning normally prior to impact.

Witness Account and Impact

A witness on the ground, working with the pilot, was positioned in a drainage wash. The witness reported that the airplane was circling overhead and that they had just identified a coyote den with coyotes moving up and down the wash. The airplane then moved out of the witness's field of view, and shortly thereafter, the witness heard the sound of the aircraft impacting the ground.

Aircraft Examination and Conditions

Weight and balance calculations performed after the accident revealed that the airplane was loaded 1.6 inches beyond its aft center of gravity limits. This condition would result in less stable flight characteristics, particularly during slow flight maneuvers. Additionally, based on standard atmospheric conditions and temperatures recorded at nearby reporting stations, the density altitude at the time of the accident was approximately 10,000 feet. While previous accidents involving similar flight regimes have been associated with wake vortex encounters, it could not be determined from available evidence whether the airplane encountered its own wake vortices.

Investigation report by the U.S. National Transportation Safety Board (NTSB) historical archive. Original record: https://carol.ntsb.gov/event/20070608X00696. This page is a structured re-presentation; facts and quotes are in the National Transportation Safety Board (NTSB), United States.