WPR11LA463 · Cessna 177 UNDESIGNAT
Cessna 177 UNDESIGNAT · Accident: loss of engine power (partial) during initial climb
From Southwest Wyoming Regional Airport (RKS) to Alva Regional Airport (AVK)
Narrative check · The NTSB narrative appears to contradict this record's aircraft involved. Values are shown as recorded, not corrected; compare with the narrative.
Event
- NTSB case
- WPR11LA463
- 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
Cessna 177 UNDESIGNAT Narrative disagrees
- Aircraft type
- Cessna 177
- 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
- N3152T
- Operator
- Phillip M. Prigmore · private individual
- Onboard fatalities
- Unknown
- Route
- From Southwest Wyoming Regional Airport (RKS), Rock Springs, WYTo Alva Regional Airport (AVK), Alva, OK
- 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
- Personnel issues › Task performance
Approximate · Coordinates as recorded by the NTSB; no uncertainty radius is established.
NTSB narrative
According to the pilot, he leaned the mixture in order to start the engine, but he did not lean the mixture prior to takeoff and did not remember using the Before Takeoff checklist. Shortly after takeoff and during the initial climb, the engine power was smooth and strong, but, about 500 feet above ground level, the engine started vibrating and the airplane began to lose altitude. Not being able to return to the airport, the pilot made an emergency off-field landing. During the landing roll, the left main landing gear impacted a hole or a berm, which resulted in the collapse of the left main gear. A postaccident engine run revealed no anomalies with the engine that would have precluded normal operation. The airplane’s owner’s manual notes that, for maximum rate-of-climb performance at airports above 5,000 feet, the mixture control should be leaned. The elevation of the airport was 6,764 feet. The density altitude at the time of the accident was calculated to be 7,907 feet.
Probable cause
The pilot did not lean the fuel mixture prior to takeoff, which resulted in the engine's inability to attain sufficient power due to the rich mixture, and his inadequate preflight planning.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record WPR11LA463
- Event ID
- 20110923X40934
- Case number
- WPR11LA463
- 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: 741c5984710551a4445970b7196c0c20c20d7eda18ad7741d641c26de87d0c8b; retrieved 2026-09-15T16:46:18.079Z.