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WPR16LA101 · Antonov AN2

6 May 2016 · San Bernardino, CA, United States

American Airpower Heritage Flying Museum Antonov AN2 · Accident: fuel contamination en route

From Upland-Cable Airport (CCB) to San Bernardino International Airport (SBD)

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Event

NTSB case
WPR16LA101
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

Antonov AN2

Aircraft type
Antonov AN2
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
N2AN
Onboard fatalities
Unknown
Route
From Upland-Cable Airport (CCB), Upland, CATo San Bernardino International Airport (SBD), San Bernardino, CA
Aircraft age
About 32 years (built 1984)
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
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
Fuel contamination
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 systems
  • Personnel issues › Task performance

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

NTSB narrative

The commercial pilot was entering the airport traffic pattern for landing during a familiarization flight. He reported that he turned on the carburetor heat, switched the fuel tank selector to the right fuel tank, and shortly thereafter, the engine experienced a total loss of power. The pilot attempted numerous times to restart the engine but was unsuccessful. After realizing that he would not be able to reach the runway, he decided to make a forced landing to a small field. During the landing approach, the airplane contacted a power line, nosed over, and came to rest inverted, resulting in substantial damage to the wings and fuselage.

During the postaccident examination of the airplane, about 16 ounces of water were removed from the fuel system. Water was present in the lower gascolator, the fine fuel filter (upper gascolator), and subsequent fuel line to the carburetor inlet. A brass screen at the carburetor inlet and 2 carburetor fuel bowl thumb screens also contained corrosion, water, and rust.

The approved aircraft inspection checklist called for washing the carburetor and main fuel filter every 50 hours and cleaning and/or replacing the fine fuel filter every 100 hours. The fine fuel filter is not easily accessible and not able to be drained during a preflight inspection. The mechanic who completed the most recent inspection stated that he did not drain or check the fine fuel filter. The last logbook entry that specifically stated the fuel filters were cleaned was about 4 years before the accident.

Probable cause

The mechanic’s failure to inspect the fine fuel filter gascolator as required during the most recent inspection, which resulted in a total loss of engine power due to fuel contamination.

Verbatim NTSB analysis and probable cause from the NTSB dataset

Sources

NTSB record WPR16LA101
Event ID
20160506X61121
Case number
WPR16LA101
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: 1219864e397df2f8ba98bfe853367332254e4e64cc9ce78a688952a27f6e361b; retrieved 2026-09-16T03:21:35.608Z.