Casualties unknown

1993-01-09: DE Havilland DHC-8-311 (N433AW) — Air Wisconsin, Inc. — Savoy, IL

Savoy, IL, US

On January 9, 1993, a DE Havilland DHC-8-311 (registration N433AW) operated by Air Wisconsin, Inc. was involved in an aviation accident near Savoy, IL. Investigators recorded the probable cause as: THE TOTAL FAILURE OF THE INBOARD RIGHT MAIN LANDING GEAR WHEEL AXLE DURING THE INITIAL CLIMB. This summary draws on records from the U.S. National Transportation Safety Board (NTSB) historical archive; 4 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
Aircraft registered N433AW
Aircraft registered N433AW. Photo: redlegsfan21 from Vandalia, OH, United States / CC BY-SA 2.0, via Wikimedia Commons

After a delayed runway turn, ground crew observed the #3 main landing gear wheel leaning. Despite this, the flight departed; the wheel separated shortly after liftoff. Investigation revealed axle fracture from degraded #3 inner wheel bearing with water-contaminated grease.

Pre-Departure Events

The flight was delayed on the runway after the flight crew exceeded the power nosewheel steering range during a tight 180-degree turn into position. Attempts to straighten the castering nosewheel using differential power and brakes were unsuccessful, prompting the crew to call for ground personnel to assist.

Ground Personnel Observations

Upon arrival, ground personnel reported that the inboard wheel of the right main landing gear (the #3 wheel) appeared to be leaning against the strut. However, the co-pilot stated that the landing gear appeared normal, and the flight subsequently departed.

Inflight Incident

Shortly after liftoff, the #3 wheel fell to the ground.

Post-Accident Examination

Examination revealed that the fracture of the axle was the result of the degradation and failure of the #3 inner wheel bearing. There was evidence of water contamination in the wheel bearing grease.

Investigation report by the U.S. National Transportation Safety Board (NTSB) historical archive. Original record: https://carol.ntsb.gov/event/20001211X11665. This page is a structured re-presentation; facts and quotes are in the National Transportation Safety Board (NTSB), United States.