SEA89LA110 · Cessna 172
Cessna 172 · Accident: uncontrolled altitude deviation while maneuvering
From Sunriver Airport (S21) to Crater Lake-Klamath Regional Airport (LMT)
Narrative check · The NTSB narrative appears to contradict this record's location. Values are shown as recorded, not corrected; compare with the narrative.
Event
- NTSB case
- SEA89LA110
- 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 172
- 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
- N1365E
- Operator
- Paul Cap
- Onboard fatalities
- Unknown
- Route
- From Sunriver Airport (S21), Sunriver, ORTo Crater Lake-Klamath Regional Airport (LMT), Klamath Falls, OR
- 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
- Maneuvering
- 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
- Uncontrolled altitude deviation
- 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
- Destroyed
Cause areas
- Pilot in command › Clearance, not maintained
- Pilot in command › In-flight planning/decision, improper
- Pilot in command › Remedial action, delayed
Approximate · Coordinates as recorded by the NTSB; no uncertainty radius is established.
NTSB narrative
THE PLT & PASSENGER WERE CONDUCTING AN EAGLE SURVEY FLT. THEY MADE A PASS OVER AN EAGLE'S NEST, NORTH OF LEMOLO LAKE TO COUNT NEWLY HATCHED EAGLETS, BUT WERE UNSUCCESSFUL. THE PLT DESCENDED TO ABOUT 400 FT AGL & WAS ON THE 2ND PASS, WHEN THE ACFT ENCOUNTERED DOWNDRAFTS. HE SAID HE APPLIED FULL POWER, BUT WAS UNABLE TO STOP A RAPID DESCENT IN TIME TO AVOID IMPACT WITH TREES. THE TERRAIN IN THAT AREA SLOPED UPWARD TO THE NORTH TO A BUTTE. ABOUT 52 MI WEST AT ROSEBURG, OR, THE 1548 PDT WIND WAS FROM 340 DEG AT 8 KTS. DENSITY ALT AT THE ACDNT SITE WAS COMPUTED TO BE 5570 FT.
Probable cause
IMPROPER INFLIGHT PLANNING/DECISION BY THE PILOT, WHICH RESULTED IN A SUDDEN ALTITUDE DEVIATION, AND HIS DELAY IN INITIATING REMEDIAL ACTION TO MAINTAIN CLEARANCE FROM THE TREES. CONTRIBUTING FACTORS WERE THE DOWNDRAFTS, HIGH DENSITY ALTITUDE, THE PILOT DIVERTING ATTENTION, AND THE TREES.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record SEA89LA110
- Event ID
- 20001213X28678
- Case number
- SEA89LA110
- 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: 104a699d1e99fd6e608222e018e5c84e7bcfa9cb36765a9db6ef5992ba6429d0; retrieved 2026-09-21T15:54:16.317Z.