Narrative:

At the gate prior to departure; my captain and I thoroughly briefed the departure. There was some discussion on headings to fly and I called and got verification from clearance delivery. The captain and I again reviewed the departure procedure and discussed altitudes and air speeds to be flown. We ran our checklists and pushed and began our taxi. I switched to tower frequency and we were cleared for takeoff. This was odd because we were still quite some distance from the end of the runway.we ran the before takeoff checklist and took the runway for departure. At 400 ft; I hit heading select and began turning the heading bug. We cleaned up on schedule and we both noticed we were not getting good heading commands. We kept the turn coming and it just didn't seem right. At that point I noticed we were accelerating rapidly. The captain engaged level change to open the speed window at which time we lost our flight directors. It was then that I realized that we never turned them on. We had inadvertently entered to/GA. We had flight directors for vertical but not lateral guidance. Upon selecting a vertical mode we exited to/GA and I recycled the flight directors both on. We slowed down; leveled off and continued the flight without further incidence.

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Original NASA ASRS Text

Title: B737-700 First Officer reported they lost their flight directors; then they realized that they never turned them on.

Narrative: At the gate prior to departure; my Captain and I thoroughly briefed the Departure. There was some discussion on headings to fly and I called and got verification from clearance delivery. The Captain and I again reviewed the departure procedure and discussed altitudes and air speeds to be flown. We ran our checklists and pushed and began our taxi. I switched to Tower frequency and we were cleared for takeoff. This was odd because we were still quite some distance from the end of the runway.We ran the Before Takeoff Checklist and took the runway for departure. At 400 FT; I hit Heading Select and began turning the Heading bug. We cleaned up on schedule and we both noticed we were not getting good heading commands. We kept the turn coming and it just didn't seem right. At that point I noticed we were accelerating rapidly. The Captain engaged Level Change to open the speed window at which time we lost our flight directors. It was then that I realized that we never turned them on. We had inadvertently entered TO/GA. We had flight directors for vertical but not lateral guidance. Upon selecting a vertical mode we exited TO/GA and I recycled the flight directors both on. We slowed down; leveled off and continued the flight without further incidence.

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.