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RA-alive
13th Sep 2011, 08:24
One of my mates was asked this question during his loft flight,

" where has the figure 61 t as the mzfw for an A320 derived from "

Would like some inputs & enhance my own know-how as the same time.

RA-alive
13th Sep 2011, 08:43
Thanx MATT101,

Am sure a lot of hours have gone in getting that value for sure.
Also someone did mention it had to do with wing bending relief.. which i have not looked up yet.

MD11forever
13th Sep 2011, 16:07
2.4. Maximum Structural Zero Fuel Weight (MZFW)
Bending moments, which apply at the wing root, are maximum when the quantity of fuel in the wings is minimum (see Figure B8). During flight, the quantity of fuel located in the wings, mWF, decreases. As a consequence, it is necessary to limit the weight when there is no fuel in the tanks. This limit value is called Maximum Zero Fuel Weight (MZFW).

http://img508.imageshack.us/img508/9376/screenshot20110913at180.png (http://imageshack.us/photo/my-images/508/screenshot20110913at180.png/)

Therefore, the limitation is defined by:
actual ZFW ≤ MZFW
The takeoff fuel is the sum of the trip fuel and the fuel reserves. Consequently:
actual TOW ≤ MZFW + Takeoff Fuel

Reference: Getting to grips with aircraft performance. 2.4

jimbo804
13th Sep 2011, 18:36
Also why you burn fuel in the centre tanks first. Keep the fuel in the wings for longer

Starbear
13th Sep 2011, 18:41
And this question highlights exactly why some "training" pilots should not be. If they cannot think of more relevant questions they should seek another career.... not the student.

RA-alive
13th Sep 2011, 18:44
MD11FOREVER,

thanx it made it so much clearer now.. understood more in detail now.

Jimbo :ok:

mutt
13th Sep 2011, 20:06
It's derived from how much you are willing to pay for it :):)

Mutt

Checkboard
13th Sep 2011, 21:53
The A320 series also keeps fuel in the wing tips (keeps the outer tanks full) as long as possible, transferring the fuel to the inner tanks towards the end of the flight (once the inner tanks are below 750 kg), to reduce bending moment (which reduces the amount of structure required, and thus the weight - increasing efficiency).

Cough
15th Sep 2011, 21:04
Checkboard - Try 319/320 only....