SEA97LA170 · Cessna 172M
Cessna 172M · Accident: in flight collision with object during takeoff
From Donald D. Coski Memorial Airport (U84) to Caldwell Executive Airport (EUL)
Event
- NTSB case
- SEA97LA170
- 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
- 0
- 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 172M
- 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
- N1418U
- Operator
- Unknown
- Onboard fatalities
- Unknown
- Route
- From Donald D. Coski Memorial Airport (U84), IDTo Caldwell Executive Airport (EUL), Caldwell, ID
- 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
- Takeoff · rejected takeoff
- 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
- In flight collision with object
- 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
- Tree(s)
- 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
- Pilot in command › Clearance, not obtained/maintained
- Pilot in command › Preflight planning/preparation, improper
Approximate · Coordinates as recorded by the NTSB; no uncertainty radius is established.
NTSB narrative
The pilot and two passengers landed on a short grass airstrip that the pilot had never landed on before. He boarded a third passenger, and performed a mental calculation for takeoff performance. He decided to takeoff uphill and into the wind. The airstrip was surrounded by tall trees, and the density altitude was about 6,000 feet. The airplane was at or near its maximum gross takeoff weight. The pilot selected 20 degrees of flaps for the takeoff, and an additional 20 degrees during climbout, despite information to the contrary on the use of flaps published in the airplane's pilot operating handbook (POH). The airplane impacted trees at the end of the runway after the pilot's attempt to abort the takeoff just prior to impact. According to the performance charts found in the POH, the airplane would have been unable to clear the trees under the given conditions. The pilot stated that the engine was unable to produce full power at takeoff. Subsequent testing of the engine did not reveal any preimpact mechanical malfunctions.
Probable cause
The pilot's failure to perform proper preflight planning for the flight, and his failure to obtain/maintain clearance from trees during takeoff. Factors contributing to the accident include the pilot's delayed remedial action, his improper use of flaps, and high density altitude.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record SEA97LA170
- Event ID
- 20001208X08512
- Case number
- SEA97LA170
- 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: local date, investigation status. Values present in the bulk record are kept.
- The date is the local date; the NTSB stores the UTC date 1997-07-20.
- API snapshot SHA-256: 60171182ed4e7402e8d167ae5f058935f12d037bbb256ea397dfcaf719481ee6; retrieved 2026-09-21T21:19:07.368Z.