N1258D Cessna 170A accident

NTSB DEN07CA086 · 2007-04-11 · Watkins, CO · near FTG

Docket — crew, injuries and powerplant

Summary

The pilot had been practicing touch-and-go landings. On his final landing, the airplane swerved to the right and the right wing struck the ground, bending the spar. The airplane then departed the runway. According to the FAA airworthiness inspector who examined the airplane, the right brake caliper assembly showed "severely worn shoes with uneven wear." The inspector surmised that when the pilot applied the brakes, the uneven brake shoe wear "caused the caliper pins to engage misaligned, contacting the rotor, locking and shearing the caliper assembly."

Full narrative

On April 11, 2007, approximately 1430 mountain daylight time, a Cessna 170A, N1258D, piloted by an airline transport-certificated pilot, was substantially damaged when the right brake failed and the airplane veered to the right and departed runway 35 at Front Range Airport (FTG) Watkins, Colorado. Visual meteorological conditions prevailed at the time of the accident. The personal flight was being conducted under the provisions of Title 14 CFR Part 91 without a flight plan. The pilot was not injured. The local flight originated approximately 1340.

The pilot had been practicing touch-and-go landings. On his final landing, the airplane swerved to the right and the right wing struck the ground, bending the spar. The airplane then departed the runway. According to the FAA airworthiness inspector who examined the airplane, the right brake caliper assembly showed "severely worn shoes with uneven wear." The inspector surmised that when the pilot applied the brakes, the uneven brake shoe wear "caused the caliper pins to engage misaligned, contacting the rotor, locking and shearing the caliper assembly."

Probable cause

A total failure during landing roll of the right brake caused by severely worn shoes, causing the caliper pins to engaged misaligned. A contributing factor was the pilot's inability to maintain directional control. The National Transportation Safety Board determined the probable cause of this accident.

Circumstances

Event type
Accident
Highest injury
None
Weather conditions
Visual Meteorological Cond
Light condition
Day
Sky condition
BKN
Ceiling (ft)
12000
Visibility (sm)
10
Wind direction
360
Wind speed (kt)
7
Temperature (F)
48
Nearest airport
Front Range
Distance from field
0.0
Airport elevation
5512

Aircraft

RegistrationMakeModelDamageFAR part
N1258D Cessna 170A SUBS 091

Sequence of events

#OccurrencePhase
1 130 Cruise
2 160 Cruise

Findings

Finding
10418 cause
24539 factor