DFW05LA009

NTSB accident investigation · Cessna 150L · Denton, TX · October 19, 2004

Accident · No injuriesLimited investigationFinal report
Date
October 19, 2004, 17:16 local (22:16 UTC)
Place
Denton, TX
Injuries
2 uninjured
Damage
Substantial damage
Phase of flight
Initial climb
Aircraft
N6870GCessna 150L
Weather
Visual (VMC) · Day
Status
Completed · report December 28, 2004
Report
Approved by Office Director
Parties
Federal Aviation Adminsitration
FAA report
20041019035099A
Case key
60404

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 loss of engine power due to the separation of the accessory drive gear bolts, and the failure of the starter-clutch assembly. A contributing factor was the lack of suitable terrain for the forced landing.

Sequence of events

NTSB’s coding before 2008: each occurrence and phase of flight, and the causes and factors under it. The codes are defined in NTSB’s coding manual.

Loss of engine power(total) - mech failure/malfTakeoff - initial climb
Accessory drive assy,drive gear - separationCause
Engine accessories,engine starter - failureCause
Forced landingEmergency landing after takeoff
On ground/water collision with objectEmergency landing
Terrain condition - none suitableFactor
Object - tree(s)

Analysis

The 2,292-hour flight instructor reported that after takeoff, the engine lost power. After initiating a forced landing to a field, the left wing impacted a tree during landing roll and the airplane came to rest upright. Review of the engine logbooks revealed that the starter clutch assembly was replaced twice within 15.64 hours. Examination of the engine revealed that the starter-clutch assembly would not rotate freely, and the starter-clutch shaft was severed into two pieces. The bolts that attach the accessory drive-gear to the camshaft were also severed.

Factual narrative

On October 19, 2004, at 1716 central daylight time, a Cessna 150L single-engine airplane, N6870G, was substantially damaged during a forced landing following a reported loss of engine power during takeoff initial climb from the Denton Municipal Airport, near Denton, Texas. The flight instructor and student pilot were not injured. The airplane was registered to and operated by a private individual. Visual meteorological conditions prevailed, and a flight plan was not filed for the 14 Code of Federal Regulations Part 91 instructional flight. The local flight originated at 1700.

The 2,292-hour flight instructor reported in the Pilot/Operator Aircraft Accident Report (NTSB Form 6120.1/2) that after completing four touch-and-go landings, "the engine lost power," approximately 300 feet above ground level (agl) at the departure end of runway 17. The flight instructor initiated a forced landing to a field, approximately 1,000 feet from the airport property. Subsequently, the left wing of the airplane impacted a tree as the airplane came to rest upright.

Examination of the airplane by an Federal Aviation Administration (FAA) inspector, who responded to the accident site, revealed that both wings were bent, and the empennage aft of the cabin area was bent approximately 90 degrees to the left.

Review of the airplane maintenance records revealed the airplane completed its most recent annual inspection on October 14, 2004, with an engine time of 1,414.87 hours since major overhaul. At the time of the accident, the engine had accumulated 1,775.94 hours since the major overhaul, with an engine total time of 5,357.04 hours.

A log book entry dated July 29, 2004, stated that the "starter was replaced with an overhauled unit and that the starter clutch was replaced with a serviceable unit," at an engine total time of 5,341.4 hours and 1,760.3 hours since major overhaul. After 7.7 hours of flight, the starter-clutch assembly was replaced again on August 27, 2004. At the time of the accident, the airplane had accumulated 7.94 hours of flight since the second replacement of the starter-clutch assembly.

The Continental O-200-A engine was examined on November 3, 2004, by a representative from Teledyne Continental Motors, an FAA inspector, and the NTSB investigator-in-charge (IIC). The examination revealed the starter-clutch assembly would not rotate freely. The starter-clutch shaft was severed into two pieces, and the bolts that attach the accessory drive-gear to the camshaft were also severed.

On November 4, 2004, a representative from Teledyne Continental Motors, under the supervision of the NTSB, examined the starter-clutch assembly at the facilities of Air Salvage of Dallas, near Lancaster, Texas. After disassembly of the clutch assembly, it was noted that the clutch rollers were shifted sideways, and two of the rollers were fused to the starter-clutch drive-shaft.

Aircraft

Registration
N6870G
Reported as
Cessna 150L
Category
Airplane
Serial number
15072370
Engine
Continental O-200-A, 100 horsepower, reciprocating
Damage
Substantial damage
Flight
Instructional · Part 91
Registered owner
Dee Ann Wakefield
Airworthiness certificate
Standard, Normal
Last inspection
Annual · October 14, 2003 · 361.07 hours before
Departed
Denton, TX
Airport
DTO · Denton Municipal Airport, runway 17, 5,999 × 150 ft, asphalt

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 · 2

As NTSB recorded them. NTSB leaves out names.

Role
Flight instructor
Age
42
Injuries
None
Certificates
Flight instructor, Commercial
Airplane ratings
Multi-engine land, Single-engine land
Instrument ratings
Airplane
Medical
Class 2, Valid Medical--no waivers/lim.
Last flight review
September 8, 2004
Seat
Right
Flight hours
2,292 total · 1,000 in this make and model · 2,245 as pilot in command · 130 in the last 90 days · 39 in the last 30 days · 5 in the last 24 hours
Role
Student pilot
Injuries
None

Weather

Conditions
Visual (VMC) · Day
Wind
260° at 6 knots
Visibility
10 statute miles
Lowest ceiling
None
Temperature
91 °F, dew point 43 °F
Altimeter
29.75 inHg
Observed at
DTO, 1 nm away

FAA reports on this event · 1

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

Other investigations on N6870G · 1

Matched to the same aircraft by N-number and date.