SEA07FA195 · Yakovlev YAK-55M
Yakovlev YAK-55M · Accident: total loss of engine power (mechanical failure) en route
From Arlington Municipal Airport (AWO) to Seattle Paine Field International Airport (PAE)
Event
- NTSB case
- SEA07FA195
- 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
- 1 · 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
Yakovlev YAK-55M
- Aircraft type
- Yakovlev YAK-55
- 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
- N55NH
- Operator
- Unknown
- Onboard fatalities
- Unknown
- Route
- From Arlington Municipal Airport (AWO), Arlington, WATo Seattle Paine Field International Airport (PAE), Everett, WA
- 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)
- Also codedOther events the NTSB coded in the sequence, such as a wire strike after a loss of power. Flight Findings uses them for its kinds of event. Glossary
- Stall/spin
- DamageDestroyed: beyond practical repair. Substantial: damage that affects the structure, performance or handling and normally needs major repair. Minor: less than that. Glossary
- Destroyed
Cause areas
- Engine assembly, bearing › Failure, total
- Fluid, oil › Exhaustion
- Pilot in command › Aircraft preflight, inadequate
- Pilot in command › Maintenance, annual inspection, not performed
- Pilot in command › Operation with known deficiencies in equipment, continued
- Pilot in command › Preflight planning/preparation, inadequate
Approximate · Coordinates from the NTSB case API, which marks them as estimated or does not say; no uncertainty radius is established.
NTSB narrative
The day before the accident, the pilot had asked his mechanic to prepare two other airplanes for flight to a fly-in the following morning. The accident airplane had not flown in a year, nor had there been any entries in the maintenance logbooks in the last four years; it did not have a current condition inspection recorded in the logbooks. The mechanic said that he had been in the process of installing an intake oil drain kit, which drains oil from the lower 3 cylinders from a common quick drain. The mechanic said that the project was not complete, but it had progressed to the point that he had put new oil in the engine. On the morning of the accident, the pilot had to move the airplane out from the back of the hangar and install the engine cowling before flight. He flew to the airport where the fly-in was being held and landed without incident. On his return flight, as he approached the airport, he radioed the tower controller and said that his engine was running rough. Approximately two minutes later, he said that his engine had lost power, and he was going down. A witness on the ground said that he heard a loud bang and looked up to see blue-gray smoke coming from the airplane. Another witness said she saw the airplane making a low left turn, when it flipped inverted and spiraled to the ground. The airplane impacted in a residential area, approximately 15 feet behind a home. A post impact fire consumed the airplane. During an engine teardown, a cylinder was removed and significant heat distress was found on and around the main rod bearing. The main rod bearing was plastically deformed and broken; several connecting rods were bent and/or broken. Additionally, a heavy oil coating was found all along the bottom of the fuselage and most of the empennage was covered with oil. If the pilot had performed an adequate preflight before his return flight, it is likely that he would have noticed a significant loss of engine oil.
Probable cause
The pilot's inadequate preflight planning and inspection that led to oil exhaustion and a catastrophic engine failure. Also causal was the pilot's attempted operation of an aircraft with known deficiencies, and the lack of a current airworthiness inspection. Contributing to the accident was the pilot's failure to maintain an adequate airspeed while maneuvering following the engine failure.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record SEA07FA195
- Event ID
- 20070723X00982
- Case number
- SEA07FA195
- 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, coordinates. 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: be5615f2b67e903a0a4427f17e19bf5ef0fa48d08352400e844c41a91a67d382; retrieved 2026-09-20T16:28:55.598Z.