WPR18LA156 · Beech A36
Beech A36 · Accident: loss of engine power (total) en route
From Tonopah Airport (TPH) to Dodge City Regional Airport (DDC)
Event
- NTSB case
- WPR18LA156
- 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
Beech A36
- Aircraft type
- Beechcraft 36
- 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
- N191HL
- Operator
- Unknown
- Onboard fatalities
- Unknown
- Route
- From Tonopah Airport (TPH), Tonopah, NVTo Dodge City Regional Airport (DDC), Dodge City, KS
- Aircraft age
- About 39 years (built 1979)
- 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 · climb to cruise
- 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 (total)
- 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
- Aircraft › Fluids/miscellaneous hardware
- Personnel issues › Psychological
- Personnel issues › Task performance
Approximate · Coordinates as recorded by the NTSB; no uncertainty radius is established.
NTSB narrative
The private pilot reported that, after the airplane reached about 8,000 ft mean sea level for the personal, cross-country flight, he began to smell smoke and then heard a popping sound. The engine then began to lose power, and he initiated a return to the airport. During the descent, the engine lost all power, and the pilot maneuvered the airplane to land on a highway. Due to obstructions, the pilot subsequently landed the airplane on a highway median. The airplane landed hard, which resulted in substantial damage to the fuselage and wings.
Examination of the engine revealed signatures consistent with detonation, which led to the failure of the No. 4 piston, the crankcase becoming pressurized, oil being pumped overboard, and the eventual oil starvation of the engine components.
A review of data from the engine data monitor (EDM) revealed that, during the flight that occurred earlier that day, the fuel flows and engine temperatures were appropriate. However, the EDM data for the accident flight revealed that the fuel flow was significantly lower during the takeoff and en route climb portions of the flight and that the cylinder head, turbine inlet, and oil temperatures reached extremely high values.
The pilot stated that he could not specifically recall the steps he took to manage the fuel/air mixture during the flight. The low fuel flow recorded on the EDM along with the excessive temperatures suggests that the mixture was set lean. Additionally, following the accident, the mixture control appeared to be leaned for cruise flight, rather than at full rich. However, the aircraft flight manual specified that the fuel mixture should be set to full rich during all operational phases from engine start through cruise climb. Given the evidence, it is likely that the pilot improperly leaned the fuel/air mixture and that he did not adequately monitor critical engine parameters via the cockpit gauges, which led to the high engine temperatures going undetected and resulted in oil starvation and the subsequent catastrophic engine failure.
Probable cause
The pilot's failure to properly lean the fuel/air mixture and to monitor critical engine parameters during the en route climb to cruise level, which resulted in excessive engine heat and oil starvation and the subsequent catastrophic engine failure.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record WPR18LA156
- Event ID
- 20180530X44625
- Case number
- WPR18LA156
- 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: e64e21bec38f79e89c0296027f9affeae07f6bd4e595948aed2695a1c3d2844d; retrieved 2026-09-16T07:20:21.948Z.