Piper PA-22-108 N4712Z

Summary

On 16 April 2007 at about 21:00 local time, a Piper PA-22-108 registered N4712Z was involved in an accident near Ava, Missouri, United States. 2 people were on board and one died, one had minor injuries. The aircraft was substantially damaged. The NTSB has published a probable cause for this accident; it is quoted in full below.

Date

16 April 2007 at 21:00

Classification

Accident

Location

Ava, Missouri, United States

Coordinates

36.8383, -92.4667

Aircraft

Piper PA-22-108

Registration

N4712Z

Category

Airplane

Engines

1

Operator

Not recorded

Operating rule

Part 91: General Aviation

Purpose of flight

Personal

Phase of flight

Not recorded

Route

Lakeview → Mountain Grove

Aircraft damage

Substantial

Weather

VMC

Light

Day

NTSB number

CHI07LA104

1 person died.

The failure of the aileron cable eye splice during cruise flight. Contributing to the accident were improper installation and service of the crimped cable sleeve, which rendered the airplane uncontrollable.

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

Read the full NTSB narrative

The passenger reported that during cruise flight the airplane inexplicably began a shallow left turn that the pilot was unable to counteract. The pilot reportedly moved the yoke to the left and right without any effect on the left bank angle. The airplane continued the unintended left turn with an increasingly steeper bank angle for three complete turns. The passenger reported that the airplane's pitch was vertically nose-down at the completion of the third turn, at which time the airplane impacted trees and terrain. The aileron control cable circuit was examined during the investigation. The inboard end of the right aileron upper cable was missing its eye splice and thimble. The cable had an approximate 90 degree bend at the location corresponding to the eye, consistent with residual deformation associated with an eye loop. The cable separation did not exhibit any kinking or heavy rubbing. The remaining sleeve (nicropress) on the right aileron upper cable did not conform to the manufacturer's specified crimp dimensions and had tooling markings that were not consistent with the use of the specified installation tool. In a properly installed eye splice, the cable should fracture before pulling out of its corresponding sleeve. The aileron cables used had a specified limit load of 2,000 pounds. The remaining eye splice on the right aileron upper cable pulled out of its sleeve at 476 pounds. The other five eye splices tested held more than 1,600 pounds before failure occurred in the cable. A review of the aircraft's maintenance logbooks did not reveal any specific mention of aileron control cable replacement. However, given the variability in the appearance and characteristics of the other aileron cable sleeves, it is likely that the nonconforming sleeves were not of original manufacture.

Quoted verbatim from the NTSB record.