DEN03FA138 · Wright Hughes 1-B
Wright Hughes 1-B · Accident: airframe, component or system failure en route
From Northeast Wyoming Regional Airport (GCC) to Eugene Airport (EUG)
Event
- NTSB case
- DEN03FA138
- 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
- 1 · 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
Wright Hughes 1-B
- Aircraft type
- Wright HUGHES 1
- 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
- N258Y
- Operator
- Unknown
- Onboard fatalities
- Unknown
- Route
- From Northeast Wyoming Regional Airport (GCC), Gillette, WYTo Eugene Airport (EUG), Eugene, 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
- En route · cruise
- 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
- Airframe, component or system failure
- 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
- Stall/spin
- 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 › Aircraft control, not maintained
- Pilot in command › Stall/spin, inadvertent
- Propeller system/accessories, counterweight › Separation
Approximate · Coordinates from the NTSB case API, which marks them as estimated or does not say; no uncertainty radius is established.
NTSB narrative
Several witnesses at Yellowstone National Park's Midway Geyser basin area reported seeing the airplane approaching them at a "low altitude" from the southeast. The airplane was quiet, and was observed gliding with its wings tipping back and forth. Next, it was observed to corkscrew, or spiral to the ground. The airplane's propeller was a highly modified constant speed Hamilton Standard 12D40 hub. Neither of the two 7 pound counterweights were found at the accident site. Examination of the #2 counterweight bracket revealed a fatigue crack at the proximal end of the counterweight slot. The propeller's shim plates exhibited impact signatures of the two blades indicating an angular difference of 10 degrees. The propeller's cylinder was crushed on one side, locking the piston inside the cylinder; the location of the piston inside the cylinder correlated to a blade angle of 34.9 degrees. If a propeller counterweight had separated in flight, aerodynamic forces would have driven the blade towards fine pitch or low blade angle. The blade's rotation would be limited to the low blade angle, of 24 degrees, by the remaining portion of its counterweight bracket arm which would contact and be stopped by the propeller’s barrel. If one blade was at the low blade angle of 24 degrees, the measured angular difference of 10 degrees, would indicate that the other blade was at an angle of 34 degrees. The agreement between this derived blade angle of 34 degrees and the piston position of 34.9 degrees suggests that one blade was still slaved to its counterweight at the time of impact and one blade was not.
Probable cause
The in-flight loss of a propeller counterweight, followed by the pilot's loss of aircraft control during a forced landing attempt and subsequent inadvertent stall/spin to the ground.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record DEN03FA138
- Event ID
- 20030815X01342
- Case number
- DEN03FA138
- 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, coordinates. Values present in the bulk record are kept.
- The date is the local date; the NTSB stores the UTC date 2003-08-05.
- API snapshot SHA-256: 8cc6fe779a67f6c5ac94e7b75654dc55fbecf8c192227588c06b988e2efea6a3; retrieved 2026-09-20T19:00:38.606Z.