What happened
On June 7, 2010, an Air Tractor AT-602, registration N4184P, crashed while performing an aerial application flight near Knobel, Arkansas. The aircraft, operated by Standridge Flying Service, Inc., had departed from Corning, Arkansas, at approximately 1745 to spray fertilizer on a rice field.
During the mission, the pilot was conducting operations under 14 CFR Part 137. A witness observed the aircraft complete one pass over the field and then pitch up to reverse direction for a subsequent pass. Following this maneuver, the aircraft descended and disappeared behind a line of trees. Although the witness did not see the impact, the sound of the aircraft hitting the ground was heard.
The aircraft impacted the terrain east of Clay County Road 250, resulting in 1 fatality. The pilot, a 34-year-old commercial pilot with 4,200 total flight hours, sustained blunt force injuries during the crash.
The investigation
Post-crash analysis of the wreckage, located in an open rice field, revealed that the aircraft struck the ground in a near-vertical descent. The impact created a crater measuring seven feet long, four feet wide, and three feet deep. The engine and propeller were located within this crater, and the orientation of the engine suggested a vertical attitude at impact.
Significant structural damage was observed, including:
- The engine was broken downward at the mounts and firewall.
- Four of the five propeller blades had broken off at the hub.
- The chemical tank was displaced aft and broken open.
- The cockpit area, windows, and instrument panel were destroyed.
- Both main landing gears were broken aft, and the wings were crushed and buckled.
An examination of the engine performed in Clinton, Arkansas, found no abnormalities that would have prevented the production of rated horsepower. Additionally, flight control continuity was confirmed.
Findings
- The aircraft was operating under visual meteorological conditions (VMC) with a visibility of 10 statute miles and winds of 210 degrees at 5 knots.
- Toxicology tests performed on the pilot were negative.
- The aircraft's cockpit was equipped with a five-point restraint system and shoulder-mounted airbags, but the severity of the vertical impact rendered the accident generally unsurvivable.