"Leadfoot" wrote:

There is already a half ton of DU located in the tail for weight and
balance



I'm not talking about 'static balance', I'm talking about
'dynamic balance'. Some large airliners replace the normal
aerodynamic 'nose up trim' of the empennage with fuel weight to
increase economy during cruise operation only. This drastically
reduces the fore and aft stability of course and makes use of an
autopilot mandatory. Are you saying that that system is not used
on the these 747's?

It's been a long time since I worked on a 747-400. It was explained to me
that the fuel in the tail was used first. It may still be that way or they
could have changed it since I left Boeing.

I'm not a pilot Just an avioncs tech who has left the industry due to a
busted knee



Ok 'Leadfoot', thanks for the info...certainly a very nice a/c
that you worked. I've always admired them.
--

-Gord.