B737 yaw damper

[fockwulf]

According our QRH Rev58, LOSS OF BOTH ENGINE DRIVEN GENERATORS will require you to turn on the YAW DAMPER again after you have AC power.

So why in the case of LOSS OF THRUST ON BOTH ENGINES, you are not required to re-connect YAW DAMPER throughout the whole checklist?

Can someone shed some light?
Thanks a lot!

[galdian]

Off top of head, happy to be corrected.

LOSS OF THRUST BOTH ENGINES you will not lose AC power as long as the engines are windmilling, the CSD's will see to that.

If you're having a really bad day and the LOSS OF THRUST BOTH ENGINES has been caused by turbine seizures on both engines at the same time then you will lose AC power.

However, of course you would action the ENGINE FAILURE/SEVERE DAMAGE/SEPARATION checklist.

Hope that's correct.
Cheers

[fockwulf]

Thank you for your reply galdian!
I've thought of that possibility, but in the sim when I have both engine flameout (no damage), both IDG gone at the same time, TRANSFER BUS OFF/SOURCE OFF/GEN OFF BUS lights on, and I'm down to standby AC power,YAW DAMPER gone too since SMYD computer is not powered. Maybe because of different sim setup? And I can't find min N2 for IDG to work properly.
Thank you anyway!
Best Regards!