# NTSB SEA95LA013: Hiller UH-12E4, N80NW, Morton, WA, October 28, 1994 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: October 28, 1994, 14:15 local (21:15 UTC) - Place: Morton, WA - Coordinates: 46.569496, -122.329887 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=46.5695&lon=-122.3299&mi=10 - Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping) - Highest injury: No injuries - Injuries: 1 uninjured - Status: Completed, report May 9, 1995 - Report: Approved by Office Director - NTSB case key (mKey): 42082 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=SEA95LA013 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/42082/pdf - Page: https://openairdocs.org/ntsb/SEA95LA013 ## Probable cause A LEAK IN THE FUEL FILLER CAP AND WATER IN THE FUEL SYSTEM. A FACTOR TO THE ACCIDENT WAS: INADEQUATE PREFLIGHT. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Loss of engine power(total) - nonmechanical, maneuvering - fuel system,cap - leak (cause) - fluid,fuel - contamination,water (cause) - aircraft preflight - inadequate, pilot in command (contributing factor) - Forced landing, descent - emergency - In flight collision with terrain/water, descent - emergency - terrain condition - rough/uneven ## Analysis SHORTLY AFTER TAKEOFF, THE ENGINE EXPERIENCED A LOSS OF ENGINE POWER. THE PILOT INITIATED A FORCED LANDING TO AN OPEN AREA, WHERE DURING THE LANDING, THE HELICOPTER ROLLED OVER. AN ENGINE EXAMINATION REVEALED A LARGE QUANTITY OF WATER IN THE FUEL SYSTEM AND AN O-RING IN POOR CONDITION ON THE STEM OF THE FUEL FILLER CAP THAT ALLOWED FLUID TO LEAK THROUGH. ## Factual narrative On October 28, 1994, at 1415 Pacific daylight time, a Hiller UH- E4, N80NW, experienced a loss of engine power shortly after take off from Morton, Washington, and collided with the terrain. Visual meteorological conditions prevailed at the time and no flight plan was filed. The helicopter was substantially damaged and the commercial pilot was not injured. The flight was being conducted under 14 CFR 133 for the local flight. It was reported that the helicopter with a bucket on a 20 foot line had just taken off and approximately one minute later, the pilot reported a loss of engine power. An emergency landing was made to an open area, where during the landing, the helicopter collided with the terrain and rolled over. After the helicopter was removed from the accident location and secured in a hangar, an engine examination revealed water in the main fuel line from the fire shield check valve to the fuel nozzle in the engine. Approximately one-third cup of water was found in the engine-driven fuel pump filter and approximately one quart of water was found in the airframe main fuel filter. The main fuel tank sump was drained and approximately two and-a-half gallons of water were removed before fuel began to drain. The helicopter had been parked outside during a heavy rain storm the day before. The fuel filler cap was removed and disassembled. It was found that an O-ring in the stem of the fuel cap was in very poor condition and allowed liquid to leak into the fuel system. The helicopter was not on level ground during the preflight inspection and the pilot reported that he did not detect any water in the system. ## Aircraft - Registration: [N80NW](https://openairdocs.org/deregistered/N80NW-2020-10-31), registration cancelled 2020-10-31, S/N 5104 (OpenAirDocs) - Reported make and model: HILLER UH-12E4 - Registry model: [Hiller UH-12E4](https://openairdocs.org/model/hiller-uh-12e4) (registry code 4360127) (OpenAirDocs) - Registry engine: [Allison 250-C20 series](https://openairdocs.org/engine/allison-250-c20-series) (registry code 03020, turbo-prop) (OpenAirDocs) - Category: Helicopter - Serial number: 5104 - Airframe hours: 3758 - Engines: ALLISON 250-C20B 420 horsepower turbo shaft - Damage: Substantial damage - Flight: Other work use, Part 133 - Operator: Northwest Helicopters Inc. - Registered owner: Northwest Helicopters Inc. - Airworthiness certificate: Standard, Normal - Last inspection: Annual, July 19, 1994, 65 hours before ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 49; commercial; airplane ratings: single-engine sea, single-engine land; medical: class 2, valid medical--w/ waivers/lim; seat: left; flight hours: 6,077 total, 5,185 in this make and model, 6,000 as pilot in command ## Weather - Conditions: Visual (VMC), Day - Wind: 220° at 6 knots - Visibility: 15 statute miles - Lowest ceiling: none - Temperature: 55 °F, dew point 52 °F - Altimeter: 30.00 inHg - Observed at: TDO, 22 nm away ## FAA reports on this event (1) The FAA's own accident and incident reports, matched to the aircraft by N-number and date (OpenAirDocs). - [Accident 19941028036819A](https://openairdocs.org/incident/19941028036819A), Oct 28, 1994: Hiller UH12E, Morton, WA, Substantial damage. Lost power on liftoff with long line bucket. Crashed. Water in fuel. Sat out heavy rain with leaky fuel cap. From the NTSB's public API. Aircraft are matched to registry aircraft by N-number and event date, checked against the reported serial number, make and model; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model. --- OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain.