Narrative:

I was the pm. We departed runway 1 out of dca. Followed the 328 dca radial. After about 10 minutes ATC gave us a 070 heading. After another 5 minutes they gave us direct swann. At some point we both remember getting a 90 heading from ATC. As we passed bross ATC told us to turn to a heading of 010 then asked if they left us on a heading. We said a couple of frequencies ago they gave us a 90 heading. Leading up to this event we received numerous heading; alt; and speed changes. Again we are not 100% sure of them giving us a 90 heading. Between getting the speed; alt; and heading changes; the only other thing I can think of is that when we received direct swann the PF never pressed the navigation button. A lot of times when given several instructions some pilots will spin the heading bug in the direction of the fix to get the turn started then maybe throw in the new altitude or speed. Bottom line we either missed pressing navigation or was given the 90 heading and ATC forgot that we were on it.

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Original NASA ASRS Text

Title: A track deviation resulted when the flight crew of an ERJ-175 failed to monitor and insure intended auto-flight modes when departing DCA on the NATIONAL DEPARTURE.

Narrative: I was the PM. We departed Runway 1 out of DCA. Followed the 328 DCA radial. After about 10 minutes ATC gave us a 070 heading. After another 5 minutes they gave us direct SWANN. At some point we both remember getting a 90 heading from ATC. As we passed BROSS ATC told us to turn to a heading of 010 then asked if they left us on a heading. We said a couple of frequencies ago they gave us a 90 heading. Leading up to this event we received numerous heading; alt; and speed changes. Again we are not 100% sure of them giving us a 90 heading. Between getting the speed; alt; and heading changes; the only other thing I can think of is that when we received direct SWANN the PF never pressed the NAV button. A lot of times when given several instructions some pilots will spin the heading bug in the direction of the fix to get the turn started then maybe throw in the new altitude or speed. Bottom line we either missed pressing NAV or was given the 90 heading and ATC forgot that we were on it.

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.