Narrative:

During the climb phase of flight XXX, ewr-cmh, we joined the airway and engaged 'navigation' mode on the FMS, and at that time engaged the autoplt. The autoplt showed all indications of engaging in navigation mode and tracking the airway. However, that indication was false. The aircraft simply maintained a heading and never tracked the airway. By the time we noticed the problem, we were 20 NM off the airway and ATC notified us of the deviation. In the future, I believe we must pay closer attention to the navigation of the autoplt and xchk its progress with the navigation chart.

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Original NASA ASRS Text

Title: ACR FLC MISS THAT AUTOPLT DOES NOT ACTIVATE AND ACQUIRE ROUTING UNTIL BROUGHT TO THEIR ATTN BY ZNY.

Narrative: DURING THE CLB PHASE OF FLT XXX, EWR-CMH, WE JOINED THE AIRWAY AND ENGAGED 'NAV' MODE ON THE FMS, AND AT THAT TIME ENGAGED THE AUTOPLT. THE AUTOPLT SHOWED ALL INDICATIONS OF ENGAGING IN NAV MODE AND TRACKING THE AIRWAY. HOWEVER, THAT INDICATION WAS FALSE. THE ACFT SIMPLY MAINTAINED A HEADING AND NEVER TRACKED THE AIRWAY. BY THE TIME WE NOTICED THE PROB, WE WERE 20 NM OFF THE AIRWAY AND ATC NOTIFIED US OF THE DEV. IN THE FUTURE, I BELIEVE WE MUST PAY CLOSER ATTN TO THE NAV OF THE AUTOPLT AND XCHK ITS PROGRESS WITH THE NAV CHART.

Data retrieved from NASA's ASRS site as of July 2007 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.