On August 14, 1990, an Air Tractor AT-301 (registration N4433S) operated by Rex & Tommy Harmon was involved in an aviation accident near Corning, AR. Investigators recorded the probable cause as: BLOCKAGE OF THE CARBURETOR AIR INTAKE BY A COLLAPSED AIR INDUCTION HOSE DUE TO IMPROPER MAINTENANCE BY AN UNKNOWN PARTY. This summary draws on records from the U.S. National Transportation Safety Board (NTSB) historical archive.
Shortly after takeoff, a total power loss occurred, forcing a landing in a muddy rice/bean field. The airplane bounced and nosed over. Inspection revealed a collapsed air induction hose and loose elbow blocking carburetor air entrance.
Incident
Shortly after taking off, the aircraft suffered a total loss of engine power. The pilot conducted a forced landing in a muddy field used for growing rice and beans. Upon touchdown, the airplane bounced once and subsequently nosed over.
Investigation
FAA inspectors examined the aircraft and observed that the air induction hose was collapsed. They also found that a 60-degree aluminum elbow was not securely fastened by its clamps, and this condition blocked the air entrance to the carburetor.
Engine Test
The operator later performed a test run of the engine. According to the source, no additional discrepancies were found.