Air Tractor AT-301 N23043

Summary

On 2 February 2000 at about 23:00 local time, a Air Tractor AT-301 registered N23043 was involved in an accident near Brawley, California, United States. One person was on board and one was seriously injured. The aircraft was destroyed. The NTSB has published a probable cause for this accident; it is quoted in full below.

Date

2 February 2000 at 23:00

Classification

Accident

Location

Brawley, California, United States

Nearest airport

Pvt Dirt Strip

Coordinates

33.0193, -115.4493

Aircraft

Air Tractor AT-301

Registration

N23043

Category

Airplane

Engines

1

Operator

Not recorded

Operating rule

Part 137: Agricultural

Purpose of flight

Aerial Application

Phase of flight

Not recorded

Aircraft damage

Destroyed

Weather

VMC

Light

Day

NTSB number

LAX00LA087

1 person was seriously injured.

Failure of the engine due to improper installation of the intake and exhaust push rods (components were switched) by unknown maintenance personnel.

Quoted verbatim from the NTSB record. This site does not paraphrase or interpret it.

Read the full NTSB narrative

The pilot was spraying sulfur on a carrot field when he lost engine power and made a forced landing in an alfalfa field, coming to rest inverted. The pilot had noted an increase in oil consumption the day of the accident. A witness observed two puffs of black smoke emanate from the airplane prior to making the forced landing. During the engine inspection it was noted that the number 5 exhaust rocker arm was found broken. Further disassembly of the number 5 cylinder revealed that the exhaust push rod was bent; due to the appearance and length it was determined that it was the intake push rod. When the exhaust push rod and the intake push rod were placed side-by-side, the intake push rod was the longer of the two and the one that was bent. Maintenance personnel stated that the only way an intake push rod could be installed in the exhaust side of the cylinder was to loosen the cylinder and pull it away from the case to allow for an increased distance between the rocker arm and lifter. When the cylinder was re-torqued, with the push rods in a switched configuration, the intake push rod would bend in the exhaust housing due to its length. After replacement of the pushrods and broken rocker arm, an engine run was conducted with no anomalies noted. Review of the engine logbook revealed that a major overhaul had been conducted on the engine approximately 3 months prior to the accident. Records indicated a mechanic and inspector conducted an inspection of the cylinders and associated components; the engine was test run with no discrepancies and then inspected by a different mechanic and inspector and signed off by all four individuals as being in airworthy condition and returned to service. A review of the engine logbooks also revealed that maintenance had been performed on the airplane since the overhaul, but not in the area of the number 5 cylinder.

Quoted verbatim from the NTSB record.