Narrative:

Taxiout; heard/felt loud bump. Stopped the aircraft. Noticed wheel assembly; rim/hubcap passing the aircraft on the right and hit the wheel well/landing gear assembly of a crj-900 aircraft waiting on taxiway. Maintenance and/or mechanical failure. Gate return. Flight delay.

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Original NASA ASRS Text

Title: A Captain reports that during taxi-out; he felt and heard a loud bump and noticed a Main Landing Gear (MLG) tire passing his B737-400 aircraft and striking the Main Landing Gear of a waiting CRJ-900 aircraft.

Narrative: Taxiout; heard/felt loud bump. Stopped the aircraft. Noticed wheel assembly; rim/hubcap passing the aircraft on the right and hit the Wheel Well/Landing Gear Assembly of a CRJ-900 aircraft waiting on taxiway. Maintenance and/or mechanical failure. Gate return. Flight delay.

Data retrieved from NASA's ASRS site as of July 2013 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.