Bell UH-1B N807SB

Summary

On 23 June 2000 at about 11:30 local time, a Bell UH-1B registered N807SB, operated by Pacific Valley Aviation, was involved in an accident near Arbuckle, California, United States. One person was on board and one died. The aircraft was destroyed. The NTSB has published a probable cause for this accident; it is quoted in full below.

Date

23 June 2000 at 11:30

Classification

Accident

Location

Arbuckle, California, United States

Coordinates

39.0200, -122.0394

Aircraft

Bell UH-1B

Registration

N807SB

Category

Helicopter

Operator

Pacific Valley Aviation

Operating rule

Part 137: Agricultural

Purpose of flight

Aerial Application

Phase of flight

Not recorded

Aircraft damage

Destroyed

Weather

IMC

Light

Night/Dark

NTSB number

LAX00LA239

1 person died.

the partial failure of the tail rotor pitch change control rod that resulted in an attempted run-on landing in dark night conditions.

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

Read the full NTSB narrative

The helicopter pilot took off about 0415 from a chemical loading site, made a left turn, and departed to spray a sunflower field. Subsequently the wreckage was located 1/2 mile west of the field. The helicopter collided with level farm terrain while in a descent. The horizontal and vertical stabilizers and tail rotor assembly appeared to be undamaged. The main rotor mast had rotated about 45 degrees forward, and symmetrical upward crushing of the cabin area occurred. A postaccident examination of the helicopter was conducted. The anti-torque control system examination revealed a tail rotor pitch change shaft's AN320 castellated shear nut stripped from the rotor end of the shaft. The threads were still intact on the shaft but missing from the nut. The shaft cotter pin hole retained the sheared portions of the cotter pin. The shearing force came from an unknown source. An ongoing wear imprint from the shaft end, into the castle nut, was noted by the lab report. Nut damage to the interior of the pitch change cap was also found during the wreckage examination.

Quoted verbatim from the NTSB record.