View Full Version : Low Gross WT,Aft CG Takeoff for 744 Freighter
waypoint5944
1st Sep 2001, 18:03
Hello everybody!
I'm a 744 flyer.
Recently I found a question for experts of 744. Our company pilot operating manual shows a procedure "Low Gross WT,Aft CG Takeoff,Freighter". And it shows a procedure to execute standing takeoff and to push the control column full forward until 80kts and etc.
But it doesn't show the specific numbers for low gross wt and aft cg. Where can I find that information?
Any informations will be appreciated.
Thanks!
Good day!
LeadSled
2nd Sep 2001, 17:19
Any time you are "light", don't get hung up on a specific figure, just be even more careful than you always are, when you are light.
As for "full forward to 80kt", ask Boeing about that, I would be most surprised if that is what it says in the original manual, my manual ( mostly Boeing) has no such reference.
Intruder
3rd Sep 2001, 06:51
Your weight & balance graphic should show an envelope within which you must use the low gross/aft CG procedure.
Our hand-generated W&B sheets have the graphic on them. If you get a computer-generated, text-only W&B form, check your Flight handbook Limitations section for the envelope.
SixDemonBag
3rd Sep 2001, 10:09
But why would you do a standing take off in this situation? Arent you just asking for trouble with 4 underslung engines producing 'x' amount of thrust, aft CoG.....
Leadsled, it might not be in Mr boeings manual, but could it be classed as 'airmanship'?
Requires min 15% derate for take-off. Low gross-weight/aft cg runs from 22%MAC at 160T to 32%MAC at 270T.
Pushing forward on the yoke at the start of the takeoff roll is just a waste of muscle power. There is no airflow at low speeds to help keep the nosewheel planted on the runway.
We don't mandate a static takeoff, but we do stress that all engines spool up evenley.
Intruder
4th Sep 2001, 00:30
SixDemonBag:
When static on the ground, even underslung engines are above the axis of rotation, which would be on the main wing landing gear.
Also, wp5944 did not fully describe his "standing takeoff" procedure in this instance. If brake release is after initial spool-up but before hitting the TO/GA button, any tendency to rock aft due to uncompressing the nose strut will be minimal.
quid:
Pushing forward on the yoke as the start helps ensure it is forward when it does become effective. Building a habit pattern is not a waste of muscle power...