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DEN92LA011 · Piper PA-22-135

1 Dec 1991 · SIEBERT, CO, United States

Piper PA-22-135 · Accident: total loss of engine power (mechanical failure) en route

From OK68 · Medford, OR to Northern Colorado Regional Airport (FNL)

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Event

NTSB case
DEN92LA011
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

Piper PA-22-135

Aircraft type
Piper PA-22
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
N3745A
Onboard fatalities
Unknown
Route
From OK68 · Medford, ORTo Northern Colorado Regional Airport (FNL), FT COLLINS, CO
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
Total loss of engine power (mechanical 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
Fuel starvation
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

  • Fluid, fuel › Starvation
  • Fuel system, vent › Blocked(total)

Approximate · Coordinates as recorded by the NTSB; no uncertainty radius is established.

NTSB narrative

DURING CRUISE FLIGHT, THE RIGHT FUEL TANK RAN DRY AND THE ENGINE QUIT RUNNING. THE PILOT SWITCHED TO THE LEFT TANK, BUT THE ENGINE WOULD NOT RESTART, DUE TO THE VENT IN THE TANK FILLER CAP BEING PLUGGED. A FORCED LANDING WAS MADE TO ROUGH UP SLOPE TERRAIN IN LOW LIGHT CONDITIONS. DURING THE LANDING, THE LANDING GEAR COLLAPSED AND THE AIRCRAFT FLIPPED OVER.

Probable cause

TOTAL LOSS OF ENGINE POWER DUE TO A PLUGGED VENT IN THE TANK FILLER CAP, RESULTING IN FUEL STARVATION. FACTORS RELATED TO THE ACCIDENT WERE: DARKNESS AND THE LACK OF SUITABLE TERRAIN FOR A FORCED LANDING.

Verbatim NTSB analysis and probable cause from the NTSB dataset

Sources

NTSB record DEN92LA011
Event ID
20001212X18585
Case number
DEN92LA011
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. Values present in the bulk record are kept.
  • The date is the local date; the NTSB stores the UTC date 1991-12-02.
  • API snapshot SHA-256: 1d06ffd8b7842a010177f40be5d2097f43352c8db890e1cd68a47e27e09913b3; retrieved 2026-09-21T15:12:50.016Z.