- Date
- March 15, 1992, 11:45 local (17:45 UTC)
- Place
- Mt. Pleasant, TN
- Injuries
- 1 serious, 3 minor
- Damage
- Substantial damage
- Phase of flight
- Enroute
- Aircraft
- N174ODBeech A36
- Weather
- Visual (VMC) · Day
- Status
- Completed · report June 30, 1993
- Report
- Approved by Office Director
- Case key
- 8572
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 manufacturer's failure to provide adequate torque information which resulted in the loss of torque on the cylinder hold down nuts and the complete loss of engine power.
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.
Analysis
While cruising the engine developed a vibration and started running roughly. The pilot reduced power and established a track for an emergency landing to a nearby county airport; the airplane crashed about one mile short of the airport. Examination of the engine assembly disclosed that a piece of the crankcase was broken above number 2 cylinder and the cylinder was partially secured by one hold down nut on the bottom left side. Further examination revealed fretting between the cylinder flange and the engine case. All crankcase fractures showed signs of overload failure. The engine maintenance logs disclosed that the engine's crankcase had been replaced on 10/24/90; this engine malfunction occurred 258 hours later. Subsequent to this accident, Continental motors issued a service bulletin which increased the torque value for the cylinder hold down nuts, and instructed that the standard six point hold down nuts be replaced with twelve point nuts during overhaul.
Aircraft
- Registration
- N174OD
- Reported as
- Beech A36
- Category
- Airplane
- Serial number
- E1796
- Airframe hours
- 3,273
- Engine
- Continental IO-520-BB, 285 horsepower, reciprocating
- Damage
- Substantial damage
- Flight
- Personal · Part 91
- Operator
- Snyder, Michael C.
- Registered owner
- Snyder, Michael C.
- Airworthiness certificate
- Standard, Normal
- Last inspection
- Annual · January 7, 1992 · 30 hours before
- Departed
- HSV · Huntsville, AL
- Destination
- SPI · Springfield, IL
- Airport
- MRC · Maury County, runway 5, 5,003 × 75 ft, asphalt
Flight crew
As NTSB recorded them. NTSB leaves out names.
- Role
- Pilot
- Age
- 53
- Certificate
- Private
- Airplane ratings
- Single-engine land, Multi-engine land
- Instrument ratings
- Airplane
- Medical
- Class 2, Valid Medical--w/ waivers/lim
- Seat
- Left
- Flight hours
- 1,420 total · 87 in this make and model · 1,262 as pilot in command · 24 in the last 90 days · 9 in the last 30 days
Weather
- Conditions
- Visual (VMC) · Day
- Wind
- 10° at 15 knots
- Visibility
- 15 statute miles
- Lowest ceiling
- 4,500 ft overcast
- Temperature
- 45 °F, dew point 21 °F
- Altimeter
- 30.00 inHg
- Observed at
- BNA, 35 nm away