Cessna 207 N6908M

Summary

On 28 July 2022 at about 01:25 local time, a Cessna 207 registered N6908M, operated by Grant Aviation Inc, was involved in an accident near Dillingham, Alaska, United States. 3 people were on board and nobody was injured. The aircraft was substantially damaged. The NTSB has published a probable cause for this accident; it is quoted in full below.

Date

28 July 2022 at 01:25

Classification

Accident

Location

Dillingham, Alaska, United States

Nearest airport

Dilingham (DLG)

Coordinates

59.0447, -158.5055

Aircraft

Cessna 207

Registration

N6908M

Category

Airplane

Year built

1980

Engines

1

Operator

Grant Aviation Inc

Operating rule

Part 135: Air Taxi & Commuter

Phase of flight

Not recorded

Route

New Stuyahok → Unknown

Aircraft damage

Substantial

Weather

VMC

Light

Day

NTSB number

ERA22LA358

Nobody was injured.

Maintenance personnel’s failure to detect and correct improper rudder control system alignment, the resulting interference with the pulley’s rotation, and the accelerated corrosion and wear of the control cable, which ultimately led to its failure in flight.

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

Read the full NTSB narrative

The pilot reported that, during approach to landing, he became aware that the left rudder pedal was not responsive. He declared an emergency and landed uneventfully. Examination revealed that the left rudder cable fractured due to corrosion and severe cable wear at the left pulley location. Nearly all wires on the cable were worn to a chisel-like point, leaving a small number of wires in the core strand to fracture in ductile overstress during final separation. The cable corrosion and wear were likely accelerated due to sliding contact with the left pulley. Issues with the rudder control system installation were evident on both pulleys. Rubbing damage on the face of the left pulley indicated that the pulley was contacting adjacent structure at the outer diameter. This contact likely interfered with pulley rotation, leading to the accelerated corrosion and wear of the control cable from sliding contact within the pulley groove. Although no rubbing damage was observed on the right pulley, the cable contact pattern was offset from the groove centerline, indicating an alignment problem in the rudder control system at the right pulley. Review of the maintenance logs revealed that the last inspection of the flight controls was completed about 8 months before the accident, and an entry about 3 months later noted a stuck pulley and corrosion of the left rudder cable. The maintenance response to the entry stated, “upon further inspection, determined cable not corroded. . . No defects.” Given the findings of the postaccident examination, it is likely that the accident would have been prevented had maintenance personnel taken more proactive action at that time.

Quoted verbatim from the NTSB record.