WPR13LA015 · Beech N35
Beech N35 · Accident: loss of engine power (total) en route
From Prescott Regional Airport - Ernest A. Love Field (KPRC) to Phoenix Deer Valley Airport (KDVT)
Event
- NTSB case
- WPR13LA015
- 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
Beech N35
- Aircraft type
- Beechcraft 35
- 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
- N671VC
- Operator
- Anderson Donald e
- Onboard fatalities
- Unknown
- Route
- From Prescott Regional Airport - Ernest A. Love Field (KPRC), Prescott, AZTo Phoenix Deer Valley Airport (KDVT), Phoenix, AZ
- 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
- Defining eventThe 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
- Loss of engine power (total)
- 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
- Aircraft › Fluids/miscellaneous hardware
Approximate · Coordinates as recorded by the NTSB; no uncertainty radius is established.
NTSB narrative
The airplane was over mountainous terrain when the pilot noticed the engine oil pressure was below 30 psi. He determined that the closest suitable airport was his destination airport, and continued to that airport. Shortly thereafter, the engine oil pressure dropped to zero, and the engine began to shake violently. The pilot shut down the engine, declared an emergency, and turned towards the nearest airport displayed on his GPS, but he did not have enough altitude to glide all the way to the airport. The pilot executed a forced landing in desert terrain. During the landing, the airplane sustained substantial damage to the nose and left wing.
Postlanding photographs show oil and dirt streaks along the right side of the airplane originating from the vicinity of the engine cowling. A postaccident engine examination revealed that the lower bolts that secured the engine oil cooler were not tight and that the lower half of the oil cooler gasket was deformed, which allowed pressurized oil to exit the engine along the bottom of the oil cooler adaptor plate. Additional engine cooling baffling was also secured to the engine by the oil cooler bolts. Thermal and mechanical damage within the engine was consistent with oil starvation. The airplane had its annual inspection 6.4 hours prior to the accident. A normal part of the annual inspection would have been to remove the baffling around the engine oil cooler in order to fully access the engine; the baffling would be replaced after completion of the inspection. It is likely that the bottom bolts of the engine oil cooler where the baffling attached were not properly torqued during reinstallation.
Probable cause
A loss of engine power due to oil starvation due to loose oil cooler attachment bolts. Contributing to the accident was inadequate maintenance during the annual inspection.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record WPR13LA015
- Event ID
- 20121018X43944
- Case number
- WPR13LA015
- Dataset
- full-current
- Source SHA-256
- 5cf380f0061817c0331a6b2d8cc7e0ee3a79bea469a1001dc5c10e56f35f5ab3
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: 53984df83dc942acc5e2dfbea60446a446e9d37aa73fa753c1e55896759da988; retrieved 2026-09-15T20:12:26.564Z.