CHI94LA328

NTSB accident investigation · Mooney M20E · Plymouth, MI · September 14, 1994

Accident · No injuriesLimited investigationFinal report
Date
September 14, 1994, 18:25 local (22:25 UTC)
Place
Plymouth, MI
Injuries
1 uninjured
Damage
Substantial damage
Phase of flight
Enroute
Aircraft
N6944UMooney M20E
Weather
Visual (VMC) · Day
Status
Completed · report February 24, 1995
Report
Approved by Office Director
Case key
9683

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 pilot's improper (maintenance) modification and his initiating an operation with known deficiencies in equipment

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/malfCruise
Maintenance,modification - improperPilot in commandCause
Operation with known deficiencies in equipment - initiatedPilot in commandCause
Forced landingDescent - emergency
On ground/water collision with objectLanding
Object - fence

Analysis

The pilot stated that he noted that the airplane had developed an oil leak in the oil cooler. He isolated the leak by capping the oil lines from the engine to the cooler and initiated a flight. He reported that after about ten minutes of flight the oil pressure dropped to zero and he was attempting a forced landing when the engine began running rough and shortly thereafter suffered a total loss of power.

Factual narrative

On September 14, 1994, at 1825 eastern daylight time, a Mooney M20E, N6944U, registered to Earl R. Sobeck of Dearborn Heights, Michigan, and operated by a private pilot, struck a fence during a forced landing following a total loss of engine power. The accident occurred in an industrial area about seven miles east- northeast of the intended destination of Canton, Michigan. The airplane sustained substantial damage. The pilot reported no injuries. The personal 14 CFR Part 91 flight was operating in visual meteorological conditions. No flight plan was on file. The flight departed Detroit, Michigan, at 1815.

The pilot stated that he had made a modification to the accident airplane, which included isolating the oil cooler which was leaking. He accomplished this by capping off the engine fittings to the oil cooler hoses which blocked the lubricating oil between the engine and the oil cooler. He then departed for another airport where he intended to obtain maintenance to repair the leaking oil cooler. He stated that while enroute the engine oil pressure dropped to zero and while he was conducting a forced landing the engine began to run rough and a total power loss soon followed.

Aircraft

Registration
N6944U
Reported as
Mooney M20E
Category
Airplane
Serial number
314
Airframe hours
3,151
Engine
Lycoming IO-360-A1A, 200 horsepower, reciprocating
Damage
Substantial damage
Flight
Personal · Part 91
Registered owner
Sobeck, Earl R.
Airworthiness certificate
Standard, Normal
Last inspection
Annual · April 19, 1994 · 40 hours before
Departed
DET · Detroit, MI
Destination
1D2 · Canton, MI

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
57
Certificate
Private
Airplane ratings
Single-engine land
Instrument ratings
Airplane
Medical
Class 3, Valid Medical--w/ waivers/lim
Seat
Left
Flight hours
1,004 total · 355 in this make and model · 901 as pilot in command · 25 in the last 90 days · 6 in the last 30 days · 1 in the last 24 hours

Weather

Conditions
Visual (VMC) · Day
Wind
120° at 7 knots
Visibility
6 statute miles
Lowest ceiling
8,000 ft overcast
Temperature
77 °F, dew point 73 °F
Altimeter
30.00 inHg
Observed at
DTW, 10 nm away