The six B747-400ER's (used on the DFW route) flown by Qantas have GE CF6 donks which put out approx 11,000 lbs thrust more that the RR donks on the standard B744's. The idle thrust setting is significantly higher on these GE's and causes pilots to use frequent brake applications to control the taxy speed.
I'd be interested if one of our engineers can explain why the GE idle setting needs to be so high
Flaps out during taxi?
If memory serves (and it often doesn't) the CF6 powered 744.
Engines to flight idle when flaps away from up.
Different to RR powered 744.
I will try find a refference in the Schematic manual..