- Date
- April 7, 1991, 12:48 local (16:48 UTC)
- Place
- Mahopac, NY
- Injuries
- 2 minor
- Damage
- Substantial damage
- Phase of flight
- Approach
- Aircraft
- N23179Piper J-4A
- Weather
- Visual (VMC) · Day
- Status
- Completed · report May 27, 1993
- Report
- Approved by Office Director
- FAA report
- 19910407009219A
- Case key
- 36901
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 erratic performance of the left magneto resulting in inadequate climb capabilities and in flight collision with terrain.
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
During an initiated go-around at Mahopac airport, Mahopac, new york, the engine experienced partial power loss. Full power could not be developed resulting in deteriorated climb capabilities. The airplane could not clear rising terrain and hit treetops, eventually contacting the ground. Post accident examination of the engine revealed that the left magneto was excessively worn and deteriorated causing the sparks to be erratically displaced to the spark plugs.
Aircraft
- Registration
- N23179
- Reported as
- Piper J-4A
- Category
- Airplane
- Serial number
- 4-546
- Airframe hours
- 1,853
- Engine
- Continental A-65, 65 horsepower, reciprocating
- Damage
- Substantial damage
- Flight
- Personal · Part 91
- Operator
- Michael Demaio
- Registered owner
- Michael Demaio
- Airworthiness certificate
- Standard, Normal
- Last inspection
- Annual · October 1, 1990 · 25 hours before
- Departed
- DXR · Danbury, CT
Flight crew
As NTSB recorded them. NTSB leaves out names.
- Role
- Pilot
- Age
- 49
- Certificate
- Private
- Airplane ratings
- Single-engine land
- Medical
- Class 3, Valid Medical--w/ waivers/lim
- Flight hours
- 249 total · 20 in this make and model · 150 as pilot in command · 3 in the last 90 days · 1 in the last 30 days
Weather
- Conditions
- Visual (VMC) · Day
- Visibility
- 15 statute miles
- Lowest ceiling
- None
- Temperature
- 84 °F, dew point 48 °F
FAA reports on this event · 1
The FAA’s own accident and incident reports, matched to the aircraft by N-number and date.