LAX01LA123 · Cessna 172RG
West Valley Flying Club Cessna 172RG · Accident: total loss of engine power (mechanical failure) en route
From Palo Alto Airport (PAO) to Palo Alto Airport (PAO)
Event
- NTSB case
- LAX01LA123
- Event typeAccident: someone killed or seriously injured, or the aircraft substantially damaged (NTSB definition). Incident: an occurrence that affected or could have affected safety, short of that. Glossary
- Accident
- InvestigationHow far the investigation had got when the record was published: preliminary, ongoing, final or completed. Unknown where the source does not say. Glossary
- Completed
- API-reported fatalities
- 0 · all aircraft and ground
- Ground fatalities
- Unknown
- OperationWhat kind of flying it was, grouped by the rules it flew under: airline (US Part 121), air taxi and commuter (Part 135), general aviation (Part 91 and similar), military or government. Glossary
- General aviation
- WeatherVisual meteorological conditions (VMC): good enough to fly by looking outside. Instrument conditions (IMC): cloud or low visibility, flying by instruments. Glossary
- Visual Meteorological Cond
Cessna 172RG
- Aircraft type
- Cessna 172
- Category
- Airplane
- RegistrationThe aircraft's tail number, such as N12345 or G-ABCD. Registrations are reissued, so the same one years apart can be a different aircraft. Glossary
- N6307R
- Operator
- West Valley Flying Club
- Onboard fatalities
- Unknown
- Route
- From Palo Alto Airport (PAO), Palo Alto, CATo Palo Alto Airport (PAO)
- Aircraft age
- Not recorded
- Flight rulesThe regulations the flight operated under: in the US, Part 91 (general aviation), Part 121 (airlines), Part 135 (air taxi and commuter) and others; for flights abroad, the NTSB's coarser commercial or non-commercial code. Glossary
- Part 91: General Aviation
- Phase of flightThe stage of the flight when things started to go wrong: standing, taxi, takeoff, initial climb, en route, maneuvering, approach or landing. Glossary
- En route · cruise
- First occurrenceThe single coded event the NTSB judges best describes what happened (records from 2008 on). Older records name the first occurrence in the sequence instead. Glossary
- Total loss of engine power (mechanical failure)
- DamageDestroyed: beyond practical repair. Substantial: damage that affects the structure, performance or handling and normally needs major repair. Minor: less than that. Glossary
- Substantial
Cause areas
- Company maintenance personnel › Maintenance, annual inspection, inadequate
- Fluid, oil › Loss, total
- Lubricating system, oil filter/screen › Not safetied
Approximate · Coordinates as recorded by the NTSB; no uncertainty radius is established.
NTSB narrative
On the landing roll out following an emergency landing, the nose landing gear dug into the soft dirt and the airplane nosed over. During cruise, the CFI asked the student if he heard knocking. The student replied that he did hear the knocking. Both pilots saw the oil pressure gage reading zero, simultaneously the knocking increased, and then the engine quit. The external examination of the engine revealed that the bottom of the fuselage, firewall, and the rear of the engine were coated with oil. The inspection further revealed that the oil filter had not been tightened or safety wired to the engine. Review of the engine logbook disclosed that an oil change was completed the day prior to the accident.
Probable cause
Failure of company maintenance personnel to properly install and safety wire the oil filter, which subsequently lead to a loss of engine power.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record LAX01LA123
- Event ID
- 20010405X00710
- Case number
- LAX01LA123
- Dataset
- historical-pre2008
- Source SHA-256
- 89e2df6d848e7ab3b42e7d7c7a03ff403303057a26ca04c95b3ea67201c3ce74
Source notes (4)
- Unreviewed is an editorial label, not an investigation status. API-sourced is not report-checked or human-reviewed. Explicit event totals are used without summing aircraft injury tables; onboard allocation is withheld. Unknown values remain unknown. The operation category is mapped from the NTSB-reported FAR part and has not been reviewed.
- Filled from the NTSB case API where the bulk record had no value: investigation status. Values present in the bulk record are kept.
- The date is the local date, which is the same as the UTC date the NTSB stores.
- API snapshot SHA-256: 94b41f03f5c83f527e88748f5af3e9740db43526d6913f53e6af781914489ac2; retrieved 2026-09-22T12:05:29.378Z.