# Accident 19990905047449A: Cessna 150M, Menlopark, CA, September 5, 1999

- Type: FAA accident report (Accident/Incident Data System), as reported
- Date: September 5, 1999, 14:22 local time
- Place: Menlopark, CA
- Damage: Substantial damage
- Phase of flight: Fcd/Prec Ldg From Cruise
- Operating rules: General operating rules (Part 91)
- Location: 37.4504° N, 122.1702° W: From the FAA, an estimate near the named town, within about 3 miles
- Nearby events: https://openairdocs.org/map.md?lat=37.4504&lon=-122.1702&mi=10
- Aircraft: N8135U, a cancelled registration (https://openairdocs.org/deregistered/N8135U-2017-06-07) (OpenAirDocs)
- Registry model: Cessna 150M (registry code 2071830, https://openairdocs.org/model/cessna-150m) (OpenAirDocs)
- Registry engine: Continental 0-200 series (registry code 17020, https://openairdocs.org/engine/continental-0-200-series) (OpenAirDocs)
- Reported make and model: CESSNA 150M
- Reported engine: CONT O200A
- People aboard: 1
- Fatal injuries: 0
- Pilot flight hours: 72 total, 70 in this make and model, 30 in the last 90 days
- NTSB investigation: [NTSB LAX99LA295](https://openairdocs.org/ntsb/LAX99LA295) (OpenAirDocs)
- FAA source: FAA Aviation Safety Information Portal (https://asip.faa.gov/)
- Page: https://openairdocs.org/incident/19990905047449A

## Narrative

As the FAA filed it, in capitals; the FAA replaces private details with ^PRIVACY DATA OMITTED^.

(.4) THE PILOT HAD JUST DEPARTED THE AIRPORT AND WAS OVER THE SAN FRANCISCO BAY WHEN THE ENGINE SUDDENLY LOST POWER. HE ATTEMPTED TO MAKE AN EMERGENCY LANDING ON A NEARBY BRIDGE BUT HAD INSUFFICIENT ALTITUDE AND LANDED IN THE WATER ON THE SHORE SHORT OF THE AREA.  THE AIRPLANE NOSED OVER WHEN THE NOSE WHEEL PLOWED INTO THE MUD.  POSTACCIDENT EXAMINATION OF THE ENGINE REVEALED THAT THE SPARK PLUGS WERE NOT PRODUCING ANY SPARK.  THE 'P-LEADS' WERE GROUNDED AT A SHORT IN A TIE-WRAPPED WIRE BUNDLE UNDER A GROMMET AT THE FIREWALL.  THE INSULATION WAS MELTED AND THE INSIDE CONDUCTOR WAS CONTACTING THE RADIO SHIELDING OF THE WIRE WHERE IT WAS ATTACHED TO THE AIRFRAME.  ADDITIONAL EXAMINATION OF THE ENGINE FOUND THAT THE REAR WALL SECTION OF THE LEFT MUFFLER WAS MISSING, WITH THE REMAINING EDGES ERODED.  WITH THE MUFFLER WALL MISSING, HOT EXHAUST GASES WERE DIRECTED TOWARDS THE FIREWALL WHERE THE SHORTED SECTION OF THE 'P-LEADS' WERE LOCATED.  MAINTENANCE ACTIONS HAD BEEN PERFORMED IN THE ENGINE COMPARTMENT THREE TIMES IN THE PAST 2 MONTHS, WITH THE LAST MAINTENANCE ACTIVITY 3 DAYS PRIOR TO THE ACCIDENT WHEN A CYLINDER WAS REPLACED.  THE LOSS OF POWER EVENT OCCURRED ON THE FIRST FLIGHT FO LLOWING RETURN OF THE AIRPLANE TO SERVICE. (-23) ON SEPTEMBER 5, 1999 AT 1422 HOURS PACIFIC DAYLIGHT TIME, A CESSNA 150M, N8135U EXPERIENCED COMPLETE ENGINE FAILURE APPROXIMATELY 2 MILES NORTHWEST OF THE PAO ALTO AIRPORT. THE CESSNA 150 HAD JUST DEPARTED THE PALO ALTO AIRPORT AND WAS AT AN ALTITUDE OF 900 FEET AGL WHEN THE ENGINE QUIT. THE PRIVATE PILOT, THE SOLE OCCUPANT WAS NOT INJURED. THE AIRPLANE WAS OPERATED BY OAKLAND FLYERS, OAKLAND, CALIFORNIA, UNDER THE PROVISION OF 14 CFR PART 91 AND RENTED BY THE PILOT FOR A LOCAL AREA PERSONAL FLIGHT. THE PILOT ATTEMPTED TO LAND THE AIRPLANE ON A DIRT ACCESS ROAD PARALLEL TO THE WEST END OF THE DUMBARTON BRIDGE, THE AIRPLANE CAME TO REST INVERTED AND SUSTAINED SUBSTANTIAL DAMAGE. NO FLIGHT PLAN WAS FILED AND VISUAL METEOROLOGICAL CONDITIONS PREVAILED AT THE TIME OF THE ACCIDENT.

## The NTSB's investigation of this event (1)

From the NTSB's public API. Aircraft are matched to registry aircraft by N-number and event date, checked against the reported serial number, make and model; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model.

- [NTSB LAX99LA295](https://openairdocs.org/ntsb/LAX99LA295), Sep 5, 1999: Cessna 150M (N8135U), Menlo Park, CA, substantial damage. Probable cause: The fatigue failure of the left muffler rear wall, which resulted in hot exhaust gasses being ported onto, and shorting, the magneto p-lead wires. The failure of maintenance personnel to detect the…

From the FAA Accident/Incident Data System. Reports are matched to registry aircraft by N-number and event date, checked against the reported make and model; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model. For accidents, the NTSB's own investigation is the fuller record.

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