Wikiposts
Search
The Pacific: General Aviation & Questions The place for students, instructors and charter guys in Oz, NZ and the rest of Oceania.

Flight fuel.

Thread Tools
 
Search this Thread
 
Old 8th Feb 2012, 08:53
  #1 (permalink)  
Thread Starter
 
Join Date: Oct 2009
Location: In the doghouse
Posts: 497
Likes: 0
Received 2 Likes on 1 Post
Flight fuel.

Can you guys please help me settle a bet.
I will redirect said combatant here should the chips fall in my favor.
I reserve the right to never tell him should I be wrong.

For planning purposes, and lets assume you are doing a W&B for each leg of a 3 leg flight, the fuel you will PLAN to burn on each leg i.e the amount for the weight calc will be which of the following?

Flight fuel
Variable reserve
Fixed reserve
Holding/alternate
Taxi

Thanks in advance.
Homesick-Angel is offline  
Old 8th Feb 2012, 09:06
  #2 (permalink)  
 
Join Date: Aug 2011
Location: toontown
Posts: 61
Likes: 0
Received 0 Likes on 0 Posts
For wt&ballance,the two worst cases, take off wt,ie gross wt-taxi fuel and zero fuel wt. If you are working out payload available on each sector, you use the fuel burn of taxi+flt fuel,any other fuel burnt would result in a lower landing wt butyou would not plan on it
outside limits is offline  
Old 8th Feb 2012, 09:06
  #3 (permalink)  
 
Join Date: Dec 2004
Location: -28.1494 / 151.943
Age: 68
Posts: 463
Likes: 0
Received 0 Likes on 0 Posts
Flight fuel & taxi ..... can't see how you would PLAN to use the rest.
Avgas172 is offline  
Old 8th Feb 2012, 11:45
  #4 (permalink)  
 
Join Date: Dec 2010
Location: In the soup
Posts: 214
Received 26 Likes on 14 Posts
Plan for the worst, w&b at MTOW, and zero fuel weight. The reason being, most aeroplanes can be loaded up so far aft that they can be out of balance at zfw. Now, worst case is you lose all your fuel on board for whatever reason, last thing you need when your attempting a forced landing is to be outside the envelope. An extreme and unlikely scenario yes, but accidents have occurred in similar circumstances.

Sox
DropYourSocks is offline  
Old 8th Feb 2012, 12:03
  #5 (permalink)  
 
Join Date: Jul 2003
Location: Somewhere
Posts: 3,071
Received 138 Likes on 63 Posts
Yes absolutely you should locate your TOW and your ZFW on your CoG and plot your fuel burn. On some aircraft it is possible to start within the CoG and burn out of it.
neville_nobody is offline  
Old 8th Feb 2012, 18:13
  #6 (permalink)  
 
Join Date: Nov 2008
Location: The Shire
Posts: 2,890
Likes: 0
Received 1 Like on 1 Post
You can't plan to burn your fixed reserve.

You also don't need your variable reserve to cover the entire flight. You can plan variable reserve to intermediate points and recalculate enroute. You don't think an intercontinental long haul aircraft carries 10% extra fuel for the entire flight to you?

On a trim sheet I would always plot TOW, ZFW and LW.

This was my last check to make sure I didn't bust MLW, MTOW and MZFW, along with being in the correct envelope as the fuel burnt off.
The Green Goblin is offline  
Old 8th Feb 2012, 21:23
  #7 (permalink)  
 
Join Date: Sep 2002
Location: Horn Island
Posts: 1,044
Received 33 Likes on 8 Posts
Out of interest, I note only one response is directed at your question, the rest just want to spruik information

I am not sure if it's written anywhere, I don't think so.
I believe you would plan on burning flight fuel and taxi fuel. That would leave you with the max possible fuel left for your subsequent sector and if you draw a line between TOW and ZFW and that line remains within the envelope all is good, that should cover the case of burning your reserve fuel, particularly your variable.

If you plan on burning your variable reserve then the planned TOW maybe lower than actual.
RENURPP is offline  
Old 8th Feb 2012, 22:32
  #8 (permalink)  
 
Join Date: Jun 2001
Location: OZ
Posts: 1,129
Received 12 Likes on 6 Posts
My take on this type of operation is for W&B purposes, plan to use flt fuel + taxi fuel for the leg. Should you use any variable reserve then your LW is conservative and your next TOW is also conservative unless you refuel. Always ensure that the a/c will be in trim from your T/O fuel load to empty tanks with no exceptions.

For FUEL planning on a multi sector day, plan to burn flt fuel, taxi fuel and variable reserve each leg so that your planned fuel for the next sector is conservative. Is is a legitimate method to plan for variable reserve for the longest leg only with the caveat that you may run into a problem should you burn some of your variable on the early sector(s). A matter for your judgment.
mustafagander is offline  
Old 9th Feb 2012, 03:41
  #9 (permalink)  
 
Join Date: Jun 2001
Location: Boldly going where no split infinitive has gone before..
Posts: 4,786
Received 44 Likes on 20 Posts
Actually, do what you like!

You can plan to use Variable or not. Whether you do would probably be a function of whether doing so restricts your payload and what your companies policy is on carrying excess fuel.

You just can't DEPART for your last leg without the required fuel FOR that leg, no matter how you planned originally.
Wizofoz is offline  
Old 9th Feb 2012, 03:52
  #10 (permalink)  
 
Join Date: Dec 2008
Location: melb
Posts: 2,162
Likes: 0
Received 1 Like on 1 Post
That pretty much sums it up well there 'wiz':-) Obviously on a 3 leg trip the first 2 legs yr good to go fuel wise (W&B checked at the start)


Wmk2
Wally Mk2 is offline  
Old 9th Feb 2012, 07:43
  #11 (permalink)  
 
Join Date: Dec 2004
Location: -28.1494 / 151.943
Age: 68
Posts: 463
Likes: 0
Received 0 Likes on 0 Posts
I concur with RENURPP ....
Avgas172 is offline  
Old 11th Feb 2012, 03:35
  #12 (permalink)  
 
Join Date: Jul 2001
Location: Australia
Posts: 4,955
Likes: 0
Received 1 Like on 1 Post
Homesick Angel,

A short, sharp summary is that, if you are the pilot in command, you are required to plan the loading of the aircraft and the fuel usage, so that, from initial startup and taxi to final shutdown, the aircraft is maintained withing the aircraft limitations and Weight and Balance envelope.

See: CARs 233 & 235.

Tootle pip!!
LeadSled is offline  

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off



Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service

Copyright © 2024 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.