Yaw Dampers INOP

[mtabb 0]

I need the advise of an expert on the 747-400. When I begin from cold and dark with this aircraft and take it through the startup process, I get to the end of the process where I'm starting engines after programming everything including route and legs. After starting engines and having all systems up and running, I end up repeatedly with the YAW Damper in the Inop condition and I am not able to fly. I've tried going back and shutting down all systems and re-setting the inertial nav systems, I may be missing a step in the start up process but can somebody help me find the missing step. I fly the MD11 with no problem of this sort. Thanks,

[Ioan92 63]

As far as I know, the "Yaw Dampers" come online as soon as the IRS system is aligned and set to NAV. Hope I'm of use :)

[yos233 1]

The Yaw Dampers, left and right, are located in the upper right corner of the overhead panel. Check to see it their switch is on of off.

[mtabb 0]

There is more to it than that. If you've flown the 747-400, then you know that the Yaw Damper buttons (left and right) have a round "ON" symbol and then the word INOP can appear on the button with the On indication. When everything is set up right, the INOP disappears leaving the ON symbol illuminitated. But thanks for the feedback. As for the first comment,,,I aggree that if the IRS systems are alligned, then the YAW Dampers should appear on and the INOP symbols should be extenguished. Just now, I was able to get the INOP to go out by turning every thing on the left panel off while engines idle. Then, I powered everything up one piece at the time. When I got to the GEN CONT switches, that's usually when the YAW DAMPER INOP lights pop on. I re-aligned the IRS systems and then powered up everything else and the YAW DAMPER INOP light stayed out. That was good,,,,,and I was able to continue on with the flight. Thanks for any suggestions you guys have.