Hi,
I fly the B744ERF and have been looking at all manuals in search of the fwd stabilizer trim limits. All I could find in the Generic Performance B744 manual is that a TO CG limit of 33% will need a stab setting of 2 units. If the info is there I can suppose it is possible to use it. Also found out that the normal TO green band fwd limit is 3.5 units and that would match a 29% CG. Now, B744ERF stab green band can displace to nose up or nose down, depending on TO flap, Thrust, and CG inserted in the FMC TO perf. So, in this case the green band will move fwd and a 2 unit setting will be in the green area. Now, in this case may we TO with a 33% CG and stay in the envelope? In my real operational envelope, with 200T TOW, we need 57T fuel to have the CG at 29% or the program will not generate a Load Sheet. But, the Perf.manual graphs allows 33% and a corrected green band allows 2 units, so, why my envelope limit is 29% for 200TOW???
Other B744 variants also have adjustable stab trim green band??
I believe that the 29% aft limit CG is a factor only for TO, if so, in the case of center tank ballast fuel, why not use this fuel latter in fllight?? is it only to comply and respect the definition of BALLAST fuel that cannot be used and is added to the ZFW?? Or is there something else??
Hope that some of you may help me with these ones.
Happy
trimmed flights
to all