FLIGHT FINDINGSAVIATION OCCURRENCE MAP
Back to map

WPR10LA424 · Grumman American AVN. CORP. AA-5A

22 Aug 2010 · Lakeview, OR, United States

Grumman American AVN. CORP. AA-5A · Accident: loss of engine power (partial) during initial climb

From Lake County Airport (KLKV) to Burns Municipal Airport (KBNO)

Report a problem

Event

NTSB case
WPR10LA424
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

Grumman American AVN. CORP. AA-5A

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
N26118
Onboard fatalities
Unknown
Route
From Lake County Airport (KLKV), Lakeview, ORTo Burns Municipal Airport (KBNO), Burns, 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
Initial climb
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 (partial)
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 › Aircraft power plant

Approximate · Coordinates from the NTSB case API, which marks them as estimated or does not say; no uncertainty radius is established.

NTSB narrative

The pilot reported that the preflight run-up was uneventful. Shortly after takeoff, at approximately 150 feet above ground level, the engine suddenly dropped rpm; the pilot verified fuel quantity, and attempted to lean the engine. Despite the pilot’s efforts, the problem persisted, and he initiated a forced landing into a nearby field. During the landing roll, the airplane’s left wing struck a fence post, and its empennage collided with high sage brush. Examination of the engine by a certificated airframe and powerplant (A&P) mechanic revealed low compression within the number three cylinder. Further examination revealed that the exhaust valve was stuck in the full open position. The examination revealed no further anomalies with the cylinder assembly or engine.

Probable cause

A partial loss of engine power during the initial climb due to a stuck exhaust valve.

Verbatim NTSB analysis and probable cause from the NTSB dataset

Sources

NTSB record WPR10LA424
Event ID
20100824X11428
Case number
WPR10LA424
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, 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: 770c3459996dda291a349d943c99ec0ef1a10914d9f61239ab1b1cbc8a58230e; retrieved 2026-09-15T14:56:01.623Z.