Sponsor Message:
Aviation Technical / Operations Forum
My Starred Topics | Profile | New Topic | Forum Index | Help | Search 
A332F Higher Gross Weight Question  
User currently offlinetrex8 From United States of America, joined Nov 2002, 4786 posts, RR: 14
Posted (3 years 11 months 3 weeks 6 days ago) and read 2975 times:
Support Airliners.net - become a First Class Member!

Why isn't there a 238K MTOW A332F offered like for the pax version? You would think for a freighter a higher MTOW would be even more important. Airbus tech data shows 233.9 and 227.9K MTOW versions only.

6 replies: All unread, jump to last
 
User currently offlineStitch From United States of America, joined Jul 2005, 31097 posts, RR: 85
Reply 1, posted (3 years 11 months 3 weeks 5 days 23 hours ago) and read 2949 times:
Support Airliners.net - become a First Class Member!

It may not be necessary if the aircraft is fuel-volume limited at the current 233t MTOW, though I know it flies farther with a lighter payload, so it might indeed be fuel-weight limited and a higher MTOW would help.

User currently offlinefrancoflier From France, joined Oct 2001, 3790 posts, RR: 11
Reply 2, posted (3 years 11 months 3 weeks 5 days 22 hours ago) and read 2867 times:

The important metric for a freighter is the MZFW.

I don't know about the A330 much, but if that MTOW extension to 238T on the pax version was done with no change to the MZFW (i.e: just to give it more range), then it would be a pretty useless feature.

Freighters don't need to fly far, they stop for fuel. The payload doesn't really care and it's more efficient that way.

[Edited 2010-10-29 18:35:02]


Looks like I picked the wrong week to quit posting...
User currently offline747classic From Netherlands, joined Aug 2009, 2177 posts, RR: 14
Reply 3, posted (3 years 11 months 3 weeks 5 days 11 hours ago) and read 2741 times:

AFAIK, the wing root bending moment is the limiting factor.
Also on the A330-200 with increased MTOW (max 238.0) the MZFW is slightly lowered, compared to the same structure at lower MTOW.


WV057---------- MTOW 236,0 tons -----------MZFW 170.0 tons
WV058---------- MTOW 238.0 tons -----------MZFW 168,0 tons

The A330F comes in two versions :

WV000--------- MTOW 233,0 tons -----------MZFW 173.0 tons
WV001--------- MTOW 227,0 tons -----------MZFW 178,0 tons

see : http://www.airbus.com/fileadmin/medi...tech_data/AC/AC_A330_Jan2010v2.pdf

Scroll to pages 45 until/incl 51 (out of 458) for all certified weight combinations of the A330-200 and A330F.

For further MTOW increase with the same MZFW, Airbus has to increase the structural strength of the center wingbox and/or wing structure.

[Edited 2010-10-30 05:14:43]


Operating a twin over the ocean, you're always one engine failure from a total emergency.
User currently offlinetrex8 From United States of America, joined Nov 2002, 4786 posts, RR: 14
Reply 4, posted (3 years 11 months 3 weeks 5 days 5 hours ago) and read 2612 times:
Support Airliners.net - become a First Class Member!

Quoting 747classic (Reply 3):
AFAIK, the wing root bending moment is the limiting factor

For those of us who were stupid enough to do the social sciences at college, what does this mean??? The wings will break off if they have to sustain the higher load of a higher TO weight???

The freighters MZFW is higher than the pax version already, is this because of strengthened floor etc?

Another maybe stupid question. There is supposed to be a version of the freighter optimized for weight OR range. Are these structurally different? Seems to me, if you increase TOW with same fuel, your range goes down and if you take more fuel, your payload goes down, so its always a trade off of one against the other, or am I missing something?.


User currently onlinewn676 From Djibouti, joined Jun 2005, 1054 posts, RR: 4
Reply 5, posted (3 years 11 months 3 weeks 5 days 1 hour ago) and read 2549 times:

Quoting trex8 (Reply 4):
For those of us who were stupid enough to do the social sciences at college, what does this mean??? The wings will break off if they have to sustain the higher load of a higher TO weight???

Basically, yes. The wing is like a big cantilever beam which, when loaded, will try to rotate around the fixed end (root). If the forces at that end become to large trying to counteract the loading on the wing, the wing will fail at that point.



Tiny, unreadable text leaves ample room for interpretation.
User currently offlinethegeek From Australia, joined Nov 2007, 2638 posts, RR: 0
Reply 6, posted (3 years 11 months 3 weeks 4 days 23 hours ago) and read 2519 times:

Quoting trex8 (Reply 4):


To explain it a bit differently, fuel in the wings doesn't load up the wing's mountings in flight, but payload does. This is why you cannot indefinitely offload fuel to increase payload. I'd be surprised if MTOW - MZFW was ever higher than wing fuel capacity. Of course, there are also limits to landing weight, but these are hit later.

HTH


Top Of Page
Forum Index

Reply To This Topic A332F Higher Gross Weight Question
Username:
No username? Sign up now!
Password: 


Forgot Password? Be reminded.
Remember me on this computer (uses cookies)
  • Tech/Ops related posts only!
  • Not Tech/Ops related? Use the other forums
  • No adverts of any kind. This includes web pages.
  • No hostile language or criticizing of others.
  • Do not post copyright protected material.
  • Use relevant and describing topics.
  • Check if your post already been discussed.
  • Check your spelling!
  • DETAILED RULES
Add Images Add SmiliesPosting Help

Please check your spelling (press "Check Spelling" above)


Similar topics:More similar topics...
H.S.C.T. Weight Question posted Mon May 7 2007 05:59:57 by Blackbird
B-757-200 Weight Question posted Sat May 31 2003 16:42:35 by MxCtrlr
RJ Weight And Balance Question posted Mon Sep 21 2009 12:03:38 by Mcg
A340 Cargo Weight And Fuel Consumption Question posted Thu Jul 31 2008 15:12:29 by TheMirror
Hypothetical Thrust To Weight Ratio Question. posted Mon Nov 26 2007 20:13:55 by Mark5388916
Question Regarding The 787 Weight Issue.. posted Sat May 26 2007 13:58:53 by Beaucaire
Question About U.S. Mail On Fedex&Airline Flights posted Fri Oct 29 2010 17:21:50 by PWM2TXLHopper
Question About A1 A2 A3.....Checks posted Wed Oct 27 2010 07:32:45 by Tangowhisky
Boeing 737's "Sky Interior" Question posted Thu Oct 14 2010 14:08:12 by PPVRA
Cockpit Door Security Question. posted Tue Oct 12 2010 10:38:52 by readytotaxi

Sponsor Message:
Printer friendly format