Narrative:

Flight proceeded and concluded without incident. After deplaning was complete; the captain of the outbound crew informed me that the flight outbound was canceled; due to the aircraft being serviced with the incorrect type of hydraulic fluid. Aircraft logs indicated aircraft had undergone a routine phase check. Unbeknownst to me; the aircraft was operated in an unairworthy condition.

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Original NASA ASRS Text

Title: EMB170 Captain reports learning after the fact that his aircraft has been serviced with the incorrect type of hydraulic fluid and was grounded.

Narrative: Flight proceeded and concluded without incident. After deplaning was complete; the Captain of the outbound crew informed me that the flight outbound was canceled; due to the aircraft being serviced with the incorrect type of hydraulic fluid. Aircraft logs indicated aircraft had undergone a routine phase check. Unbeknownst to me; the aircraft was operated in an unairworthy condition.

Data retrieved from NASA's ASRS site as of April 2012 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.