GAA18CA020

NTSB accident investigation · Cessna 150 · Pottsville, PA · October 22, 2017

Accident · No injuriesData collectionFinal report
Date
October 22, 2017, 18:15 local (22:15 UTC)
Place
Pottsville, PA
Injuries
2 uninjured
Damage
Substantial damage
Phase of flight
Unknown
Aircraft
N22092Cessna 150
Defining event
Unknown: Flight control sys malf/fail
Weather
Visual (VMC) · Day
Status
Completed · report January 11, 2018
Report
Approved by Office Director
NTSB office
General Aviation Accidents
Parties
FAA
FAA report
20171022014949A
Case key
96234

From the NTSB’s public API. By law, NTSB reports can’t be used as evidence in lawsuits over the accident.

On this page

Probable cause

The failure of the right rudder cable and subsequent loss of directional control during landing.

Findings · 5

NTSB’s coded findings. Those marked are part of the probable cause; the rest are factors or other findings. Under each, the cases with the same finding.

Wind: windshearEnvironmental issues › Conditions/weather/phenomena · Effect on operationCessna 150H: 1 caseAll aircraft: 90 cases
Wind: updraftEnvironmental issues › Conditions/weather/phenomena · Effect on operationCessna 150H: 1 caseAll aircraft: 14 cases
Wind: downdraftEnvironmental issues › Conditions/weather/phenomena · Effect on operationCessna 150H: 1 caseAll aircraft: 178 cases
Performance/control parameters: directional controlAircraft › Aircraft oper/perf/capability · Attain/maintain not possibleCessna 150H: 9 casesAll aircraft: 3,958 cases

Sequence of events

The events NTSB coded, in order, by phase of flight. The defining event is the one that best describes the accident. Under each, the cases with the same event anywhere in their sequence.

Analysis

The pilot reported that, during approach, the automatic weather observation station at the destination airport reported that the wind was from 170° at 12 knots. He added that there was "very massive choppy wind, including what could have been windshear, updrafts, and downdrafts." During the landing roll on runway 11, a wind gust blew the airplane off the runway to the left. The pilot attempted to recover, but the airplane impacted a ditch. The airplane sustained substantial damage to the fuselage and right wing. The pilot reported that there were no preaccident mechanical failures or malfunctions with the airplane that would have precluded normal operation. The Federal Aviation Administration (FAA) inspector reported that a postaccident examination revealed that the rudder cable that passed along the left side of the fuselage was separated into three pieces. The rudder cable was covered in debris, which contained red fibers. The rudder cable was splayed and exhibited signatures consistent with tension overload. The airplane's illustrated parts catalog contained a diagram titled, "Rudder Control System Installation," which displayed the cable along the left side of the fuselage cross over the right side of the airplane, in the tailcone section, and connect to the right side of the rudder horn, which provided right rudder authority. The airplane's most recent inspection was an annual, which was conducted 6 months before the accident flight. The FAA inspector interviewed the mechanic who performed the most recent annual inspection, and the mechanic reported that, during inspections, he used manufacturer data and FAA Advisory Circular, AC 43.13-1B, "Acceptable Methods, Techniques, and Practices – Aircraft Inspection and Repair." He further reported, multiple times, that he should probably "tighten up" his inspections. AC 43.13-1B contained a section titled, "Cable System Inspection," which stated the following: "Aircraft cable systems are subject to a variety of environmental conditions and deterioration. Wire or strand breakage is easy to visually recognize. Other kinds of deterioration such as wear, corrosion, and/or distortion are not easily seen; therefore, control cables should be removed periodically for a more detailed inspection. At each annual or 100-hour inspection, all control cables must be inspected for broken wire strands. Any cable assembly that has one broken wire strand located in a critical fatigue area must be replaced." It further stated the following: "Close inspection in these critical fatigue areas, must be made by passing a cloth over the area to snag on broken wires. This will clean the cable for visual inspection, and detect broken wires if the cloth snags on the cable." It is likely that the red fibers found on the rudder cable were from a red cloth used to inspect the rudder cable during the annual inspection. It is also likely that, sometime during the flight or landing sequence, the right rudder cable separated, whichsubsequently restricted the pilot's ability to recover from the loss of control during landing.

Factual narrative

The pilot reported that, during approach, the automatic weather observation station at the destination airport reported that the wind was from 170° at 12 knots. He added that there was "very massive choppy wind, including what could have been windshear, updrafts, and downdrafts". During the landing roll on runway 11, a wind gust blew the airplane off the runway to the left. The pilot attempted to recover, but the airplane impacted a ditch. The airplane sustained substantial damage to the fuselage and right wing. The pilot reported that there were no preaccident mechanical failures or malfunctions with the airplane that would have precluded normal operation. The Federal Aviation Administration (FAA) inspector reported that, during a postaccident examination, the rudder cable that passed along the left side of the fuselage was separated into three pieces. The rudder cable was covered in debris, which contained red fibers. The rudder cable was splayed and exhibited signatures consistent with tension overload. The airplane's illustrated parts catalog contained a diagram, titled "Rudder Control System Installation". This diagram displayed the cable along the left side of the fuselage cross over the right side of the airplane, in the tailcone section, and connect to the right side of the rudder horn, which provided right rudder authority. The airplane's most recent inspection was an annual, conducted 6 months prior to the accident flight. The FAA inspector interviewed the mechanic who performed the most recent annual inspection. During the interview, the mechanic reported that, during inspections, he uses manufacturer data and the FAA advisory circular, AC 43.13-1B. He further reported, multiple times, that he should probably "tighten up" his inspections. The FAA's advisory circular, AC 43.13-1B, titled "Acceptable Methods, Techniques, and Practices – Aircraft Inspection and Repair", contains a section titled "Cable System Inspection", which stated: "Aircraft cable systems are subject to a variety of environmental conditions and deterioration. Wire or strand breakage is easy to visually recognize. Other kinds of deterioration such as wear, corrosion, and/or distortion are not easily seen; therefore, control cables should be removed periodically for a more detailed inspection. At each annual or 100 hour inspection, all control cables must be inspected for broken wires strands. Any cable assembly that has one broken wire strand located in a critical fatigue area must be replaced." It further stated: "Close inspection in these critical fatigue areas, must be made by passing a cloth over the area to snag on broken wires. This will clean the cable for visual inspection, and detect broken wires if the cloth snags on the cable."

Aircraft

Registration
N22092
Reported as
Cessna 150 (H)
Category
Airplane
Serial number
15068059
Built
1967
Engine
Cont Motor O-200 SERIES, 100 horsepower, reciprocating
Damage
Substantial damage
Flight
Personal · Part 91
Operator
Pocono Mountains Flying Club Inc
Registered owner
Pocono Mountains Flying Club Inc
Airworthiness certificate
Standard, Utility
Last inspection
Annual · April 14, 2017
Departed
MPO · Mount Pocono, PA
Destination
ZER · Pottsville, PA
Airport
ZER · Schuylkill County /Joe Zerbey, runway 11, 4,599 × 75 ft, asphalt
Equipment
Unknown

Matched to the registry by N-number and the event date; the registry’s history has gaps, so older matches can be wrong. Compare the reported make and model.

Flight crew

As NTSB recorded them. NTSB leaves out names.

Role
Pilot
Age
25
Injuries
None
Certificate
Private
Airplane ratings
Single-engine land
Medical
Class 3, With waivers/limitations
Seat
Left
Restraint
Lap only
Flight hours
83 total · 82 in this make and model · 29 as pilot in command · 35 in the last 90 days · 13 in the last 30 days · 2 in the last 24 hours

Weather

Conditions
Visual (VMC) · Day
Wind
Calm
Visibility
10 statute miles
Lowest ceiling
None
Temperature
43 °F, dew point 43 °F
Altimeter
30.37 inHg
Observed at
KMUI, 18 nm away

Docket · 5

The files NTSB released with the investigation on December 11, 2017, on NTSB’s docket system: statements, records, photos and specialists’ reports. 6.8 MB in all.

FAA reports on this event · 1

The FAA’s own accident and incident reports, matched to the aircraft by N-number and date.