Casualties unknown

2000-12-05: Mooney M20J (N4101H) — Danbury, CT

Danbury, CT, US

On December 5, 2000, a Mooney M20J (registration N4101H) was involved in an aviation accident near Danbury, CT. Investigators recorded the probable cause as: Water/ice in the fuel system and the pilot's inadequate preflight inspection. This summary draws on records from the U.S. National Transportation Safety Board (NTSB) historical archive; 8 related events involving the same aircraft type or operator are linked below.

Sourcesthe U.S. National Transportation Safety Board (NTSB) historical archivePrimary reportUpdated 1781061362Data APIEditorial standards

A pilot experienced engine failure at 400-500 feet after takeoff due to water-contaminated fuel. The aircraft had sat with half-filled tanks for 2.5 weeks in freezing temperatures, and the pilot did not check for water before flight.

Incident Overview

An aircraft experienced a complete loss of engine power shortly after takeoff, leading to a forced landing. The airplane had been parked on the ramp for approximately 2.5 weeks with its fuel tanks half filled. During this period, outside air temperatures dropped to 18 degrees Fahrenheit the night before the accident and remained below freezing until about three hours before the flight. At the time of the accident, the temperature had risen to 43 degrees Fahrenheit.

Preflight and Flight Sequence

The pilot did not perform a fuel contamination check before departure. The engine start, run-up, and takeoff were normal. However, at an altitude of 400 to 500 feet, the engine failed. The pilot executed a forced landing.

Investigation Findings

Subsequent examination revealed evidence of water in a container that held fuel removed from the airplane. The presence of water in the fuel is consistent with condensation forming in the partially filled tanks over the extended period of cold weather. The lack of a preflight fuel check meant this contamination went undetected.

Investigation report by the U.S. National Transportation Safety Board (NTSB) historical archive. Original record: https://carol.ntsb.gov/event/20001220X45462. This page is a structured re-presentation; facts and quotes are in the National Transportation Safety Board (NTSB), United States.