Narrative:

We were departing ZZZ in the evening. The aircraft had been positioned to ZZZ 4 hours prior. Aircraft handler could not provide a gpu and the aircraft APU was inoperative (MEL). On battery start; the standby screens blanked out and the FMS experienced power interruptions requiring re-input of the flight plan and departure procedure. The subsequent taxi took about 30 minutes. We were cleared the ZZZX climb. This was all entered and confirmed in the FMS. During the taxi out; I noticed the heading flag appeared intermittently. Once the aircraft was in #1 position on taxiway Z; the heading switches were synchronously cycled to free and then back to slave. The hsis agreed and the heading flag went away. We were promptly cleared for departure and rolled onto runway 31L -- all checks were accomplished; no heading flag appeared and a rolling takeoff was accomplished. Upon reaching 400 ft AGL the pilot flying commanded navigation mode. The FD immediately commanded a right turn. The pilot flying initiated a turn to the right. As the pilot not flying; I was monitoring the departure -- I had the VOR bearing pointer selected on the pfd and the 176 degree course selector on the VOR CDI in preset. Seeing that we were turning in the wrong direction; away from xx as depicted by the head of the bearing pointer; I intervened and said we need to come left; direct to xx as depicted in the departure procedure. The pilot began a slow turn to the left toward xx. The FMS continued to point to the right. Xx is only about 2 miles from the departure end of runway 31L. We eventually got pointed at xx; but overshot the turn and ended up west of the 039 degree radial. At this point; the controller queried whether we were on the climb; I switched to display VOR data and the preset 176 degree course. We had full scale deflection to the left and I told the pilot he needs to come south. I then told ATC we are having navigation problems and we needed a vector. The pilot initiated a turn to the left and ATC came back with 070 degree vector to get us further east. At this point we noticed that the FMS wind indicator showing a 170 KT wind from the left; being at 7;000 ft this was erroneous data and we agreed that both fmss were erratic. When we rolled out on the prescribed 070 degree heading; the controller came back and again queried about our heading. He promptly came back and said we were about 40 degrees off to the right still; so I asked for a no-gyro vector. The controller complied and gave us stop turn on the proper heading. No heading flags were displayed; both hsis were in agreement. The only abnormality was the FMS wind showing about 170 KTS from the left. I asked the controller for a navigational aid to fly to alleviate the heading discrepancy; but the controller continued to provide no-gyro vectors out of his airspace. Once the aircraft was straight and level; the pilot asked to re-slave the gyros. We again placed the switches to free and then to slave. The hsis settled on a new heading which I confirmed with the next controller. The FMS wind immediately came back to a more credible number for our altitude. Once we were cleared direct; we were able to confirm the FMS was also navigating correctly. I informed ATC our navigation systems were back to normal and proceeded to our destination. No other navigation deviations occurred during the flight or any subsequent flights. Reference: ZZZ 1 departure and airport diagram. I believe that our gyros were slaved to the wrong heading. This accounts for the initial FD command to turn right. Once reaching cri when I told the pilot to come 'south' to get on the 176 degree course outbound; the pilot flying complied; the HSI showed a south heading; but the aircraft was actually on a southwest heading. The FMS interpreted this as a 170 KT wind from the left that was pushing us southwest as opposed to us actually heading in that direction. The heading discrepancy continued until we re-slaved the gyros. We re-slaved ourgyros while holding short for takeoff. The heading flag went away; the headings matched up exactly; and they seemed to make sense in relation to our position on the airfield. What we did not take into account was that the hold short line to runway 31L is not at the usual 90 degree angle to the runway; which is difficult to perceive at night and when dealing with such a large runway. Once taking the runway; there is a recommended practice of checking runway alignment on the HSI with expected runway. This is done to ensure you are on the correct runway. Flying out of ZZZ; it was fairly obvious we were on the correct runway and had no inclination to verify that we were actually on runway 31L. We also accomplished a rolling departure which also made it difficult to notice the heading discrepancy. The only suggestion I have is if you experience gyro problems on taxi; give them one last look right before takeoff. If you have to do a static takeoff in order to do that; make it so.

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Original NASA ASRS Text

Title: A LR60 crew misaligned the HSI's after a battery start. No gyro vectors were required after takeoff before they finally aligned the systems for proper indications.

Narrative: We were departing ZZZ in the evening. The aircraft had been positioned to ZZZ 4 hours prior. Aircraft handler could not provide a GPU and the aircraft APU was inoperative (MEL). On battery start; the standby screens blanked out and the FMS experienced power interruptions requiring re-input of the flight plan and departure procedure. The subsequent taxi took about 30 minutes. We were cleared the ZZZX climb. This was all entered and confirmed in the FMS. During the taxi out; I noticed the Heading Flag appeared intermittently. Once the aircraft was in #1 position on Taxiway Z; the heading switches were synchronously cycled to free and then back to slave. The HSIs agreed and the Heading Flag went away. We were promptly cleared for departure and rolled onto Runway 31L -- all checks were accomplished; no Heading Flag appeared and a rolling takeoff was accomplished. Upon reaching 400 FT AGL the Pilot Flying commanded Navigation Mode. The FD immediately commanded a right turn. The Pilot Flying initiated a turn to the right. As the Pilot Not Flying; I was monitoring the departure -- I had the VOR bearing pointer selected on the PFD and the 176 degree course selector on the VOR CDI in preset. Seeing that we were turning in the wrong direction; away from XX as depicted by the head of the bearing pointer; I intervened and said we need to come left; direct to XX as depicted in the departure procedure. The Pilot began a slow turn to the left toward XX. The FMS continued to point to the right. XX is only about 2 miles from the departure end of Runway 31L. We eventually got pointed at XX; but overshot the turn and ended up west of the 039 degree radial. At this point; the Controller queried whether we were on the climb; I switched to display VOR data and the preset 176 degree course. We had full scale deflection to the left and I told the pilot he needs to come south. I then told ATC we are having navigation problems and we needed a vector. The pilot initiated a turn to the left and ATC came back with 070 degree vector to get us further east. At this point we noticed that the FMS wind indicator showing a 170 KT wind from the left; being at 7;000 FT this was erroneous data and we agreed that both FMSs were erratic. When we rolled out on the prescribed 070 degree heading; the Controller came back and again queried about our heading. He promptly came back and said we were about 40 degrees off to the right still; so I asked for a no-gyro vector. The Controller complied and gave us stop turn on the proper heading. No Heading flags were displayed; both HSIs were in agreement. The only abnormality was the FMS wind showing about 170 KTS from the left. I asked the Controller for a navigational aid to fly to alleviate the heading discrepancy; but the Controller continued to provide no-gyro vectors out of his airspace. Once the aircraft was straight and level; the pilot asked to re-slave the gyros. We again placed the switches to free and then to slave. The HSIs settled on a new heading which I confirmed with the next Controller. The FMS wind immediately came back to a more credible number for our altitude. Once we were cleared direct; we were able to confirm the FMS was also navigating correctly. I informed ATC our navigation systems were back to normal and proceeded to our destination. No other navigation deviations occurred during the flight or any subsequent flights. Reference: ZZZ 1 departure and Airport diagram. I believe that our gyros were slaved to the wrong heading. This accounts for the initial FD command to turn right. Once reaching CRI when I told the pilot to come 'south' to get on the 176 degree course outbound; the Pilot Flying complied; the HSI showed a south heading; but the aircraft was actually on a southwest heading. The FMS interpreted this as a 170 KT wind from the left that was pushing us southwest as opposed to us actually heading in that direction. The heading discrepancy continued until we re-slaved the gyros. We re-slaved ourgyros while holding short for takeoff. The Heading flag went away; the headings matched up exactly; and they seemed to make sense in relation to our position on the airfield. What we did not take into account was that the hold short line to Runway 31L is not at the usual 90 degree angle to the runway; which is difficult to perceive at night and when dealing with such a large runway. Once taking the runway; there is a recommended practice of checking runway alignment on the HSI with expected runway. This is done to ensure you are on the correct runway. Flying out of ZZZ; it was fairly obvious we were on the correct runway and had no inclination to verify that we were actually on Runway 31L. We also accomplished a rolling departure which also made it difficult to notice the heading discrepancy. The only suggestion I have is if you experience gyro problems on taxi; give them one last look right before takeoff. If you have to do a static takeoff in order to do that; make it so.

Data retrieved from NASA's ASRS site as of May 2009 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.