Narrative:

We were performing a takeoff on runway 22L in ord. At the same time; a heavy aircraft was performing a takeoff on runway 28R. During our takeoff roll; the jet blast from the departing aircraft on 28R caused some of our takeoff guidance to drop and we received FD lateral and FD vertical mode off messages on our EICAS. By the time we had identified and canceled the messages and made a decision; we were already over 100 knots indicated and made the decision to continue the takeoff and select the appropriate lateral and vertical modes once airborne. The rest of the flight continued uneventfully.

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Original NASA ASRS Text

Title: E175 flight crew reported jet blast from another aircraft on the takeoff roll caused loss of the flight director vertical and lateral modes.

Narrative: We were performing a takeoff on Runway 22L in ORD. At the same time; a heavy aircraft was performing a takeoff on Runway 28R. During our takeoff roll; the jet blast from the departing aircraft on 28R caused some of our takeoff guidance to drop and we received FD Lateral and FD Vertical Mode Off messages on our EICAS. By the time we had identified and canceled the messages and made a decision; we were already over 100 knots indicated and made the decision to continue the takeoff and select the appropriate lateral and vertical modes once airborne. The rest of the flight continued uneventfully.

Data retrieved from NASA's ASRS site 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.