Narrative:

First officer pfd displayed a red X on the altitude tape at 56 KTS. We aborted takeoff on runway; returned to the gate and called maintenance. Everything was handled per SOP. Air data computer malfunctioned during takeoff roll.

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Original NASA ASRS Text

Title: EMB145 First Officer reports a rejected takeoff due to a red X on the altitude tape at 56 KTS.

Narrative: FO PFD Displayed a red X on the ALT tape at 56 KTS. We aborted takeoff on runway; returned to the gate and called Maintenance. Everything was handled per SOP. ADC malfunctioned during takeoff roll.

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.