On July 28, 1998, an Aero Commander 690 (registration N349AC) operated by Blm, U.s. Dept OF Interior was involved in an aviation accident near Ely, NV. Investigators recorded the probable cause as: The failure and separation of the left main gear wheel halves due to overload as a result of excessive air pressure. A contributing factor was the inadequate maintenance/service of the main gear tires. This summary draws on records from the U.S. National Transportation Safety Board (NTSB) historical archive.
During taxi for departure, the left main wheel separated from the axle, causing the strut to ground and damage to the wing spar and fuselage skin. Investigation revealed stripped bolts and overinflated right tire.
Incident Overview
According to statements from the pilot and observer, the aircraft was taxiing for departure when the left main wheel detached from its axle. As the strut made contact with the taxiway, the left rear wing spar was fractured and the fuselage crown skin became wrinkled.
Examination Findings
Post-incident examination of the aircraft revealed that the left wheel had separated into its two halves, with the tire having come off the wheel. All ten nuts securing the wheel halves together were found stripped off the bolts. Additionally, the air pressure in the right tire was measured using a gauge that only indicates up to 125 psi; the pressure in that tire pegged the gauge at that maximum value. According to the aircraft's flight manual, the maximum main landing gear tire pressure should be 60 psi.