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How much extra fuel can be uplifted?

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How much extra fuel can be uplifted?

Old 8th May 2018, 04:09
  #41 (permalink)  
 
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Originally Posted by new_era View Post
Now please tell me, where is the cheating, where is the illegal thing on it.
This is legitimate, as long as you actually replan for 310 and get a load sheet that gives a good landing weight at/below the limit. (Or, in the case of my airline, this isn't shown directly but there's just a takeoff weight that is predicated on that.)

What's illegal is to just say "we'll burn it off in the air" and take off at the higher weight without replanning.

"Cheating," depending on the slang of where you're from, may refer to something that's legitimate but involves a clever work-around an initial obstacle; i.e., it could be either one of the above two actions.
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Old 8th May 2018, 04:18
  #42 (permalink)  
 
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The point I have been making is that Regulatory Takeoff Weight has limitation that arise from approach and landing part. What you intend to do at landing is not enough the loads sheet before takeoff must reflect that it fulfills those (RTOW) requirements.
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Old 8th May 2018, 05:19
  #43 (permalink)  
 
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Can you give an example using the same figures in what case the limitation you are talking about is violated?

zfw…61.4 < mzfw
tow…76.8 < mtow
ldw…66.3 < mlw
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Old 8th May 2018, 14:14
  #44 (permalink)  
 
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Bergerie 1
So - all legal with problem solved and good diplomacy and publicity achieved at the same time!
I am afraid I have to disagree. There are many occasions when civil aviation authority officials come on board after landing and check the fuel remaining. They don't want to to know your story but want to see in tanks alternate fuel+30min holding fuel at alternate. If you didn't have that you would be hauled over coals. If an airline repeats such incidents their AOP is in danger.
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Old 8th May 2018, 16:08
  #45 (permalink)  
 
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vilas,
They don't want to to know your story but want to see in tanks alternate fuel+30min holding fuel at alternate. If you didn't have that you would be hauled over coals.
Not true!
Have a read of the recognised procedures when you are "committed" to a single airfield.
http://www.ifalpa.org/downloads/Leve...ncy%20fuel.pdf
or
https://publicapps.caa.co.uk/docs/33...%202015082.pdf

Company procedure is to file an ASR so any trend can be monitored.
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Old 9th May 2018, 05:43
  #46 (permalink)  
 
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I agree with Goldenrivett on this one. We discussed about it recently in this thread: Flying from A to B with minimum fuel.
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Old 9th May 2018, 06:48
  #47 (permalink)  
 
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Golden rivette and Pineteam
If you read carefully the reference you have given it only confirms what I am saying. You are supposed to keep track of fuel consumption all along in cruise and you are supposed to divert before minimum fuel situation arises. You cannot burn extra fuel to create a situation to commit to land and claim the privilege of minimum fuel. Incidently at Heathrow they have checked minimum fuel on board after landing.
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Old 9th May 2018, 08:54
  #48 (permalink)  
 
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vilas,
you are supposed to divert before minimum fuel situation arises.
If landing is assured at your destination (no weather problems etc) what is the advantage of diverting to an airfield with a single runway and arriving with only 30 mins of fuel remaining?
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Old 9th May 2018, 09:26
  #49 (permalink)  
 
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Originally Posted by dastocks View Post
I was on a flight recently where the undercarriage was lowered for about 20 minutes in the cruise in order to burn off excess fuel that had been loaded by mistake before we had departed, so clearly it is possible.
Under EASA you are allowed to depart if the Expected landing weight (dispatch) exceeds the required weight for landing performance. You will need to file two alternates.

Inflight - The expected landing weight must be at or below the landing perf limit weight.
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Old 9th May 2018, 12:24
  #50 (permalink)  
 
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Originally Posted by Goldenrivett View Post
vilas,

If landing is assured at your destination (no weather problems etc) what is the advantage of diverting to an airfield with a single runway and arriving with only 30 mins of fuel remaining?
Yes. Does not make any sense. Better to cancel alternate fuel and hold. The crew has to monitor the fuel during flight not to land with less that minimum legal fuel which is 30 min at holding speed at 1500 feet AAL. Not a situation anyone wants to be but landing with only 30 min of fuel in the tank is 100% legit. Below that, no question asked, the crew must call Mayday Fuel.
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Old 9th May 2018, 12:50
  #51 (permalink)  
 
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Goldenrivett
Far too many variations have got in the original question and we are going around in circles. IFR flight/VFR flight, Alternate required/not required/not available, remote destination all these situations have different fuel requirements, we can't discuss all in one breath. I was referring to Bergerie1. His RTOW calculation at Nairobi was incorrect. Period! Refusing some payload or passengers is always a bad idea but you have to do it many times otherwise Regulated Takeoff Weight will become a joke. You have no option unless you manipulate the BO. I do not want to repeat what I have already stated. I don't know how any one can justify doing unplanned low flying with passengers and a VIP/Semi VIP on board and claim a pat on the back.You can check weather and traffic but ask Sully he will tell you cannot check for birds. Then you burn fuel and along with it your diversion and claim privileges of a committed landing. And despite my quoting Airbus manual page number B737900er states EASA doesn't have landing weight limit. May be AIRBUS doesn't form part of EASA.
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Old 9th May 2018, 14:52
  #52 (permalink)  
 
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Originally Posted by carnival30 View Post
Hello everyone,

Please bear with me.

In our company flight plan, the format goes like this,

R/W limited t/o weight.........79.0 ( letís say the max structural t/o is for today)
Max Ldg weight.....66.4
B/o fuel..................10.0
Ldg limited t/o weight.....76.4 (adding above two)
Max ZFW......62.7
Required fuel....13.5 (excluding taxi)
ZFW limited t/o weight....76.2 (adding above two)

planned zfw...61.0
planned t/o weight...74.5
landing weight....64.5

Now the problem Iím facing about how much extra fuel I can take for this flight. I know maximum time and easy calculation is just to subtract ldg weight from max ldg weight which gives us 66.4 minus 64.5= 1.9 tons. But in the above case we are limited by zfw limited t/o weight which is 76.2 (lowest of the three above) so should we minus this from planned t/o weight 76.2-74.5=1.7 tons. I am a bit confused here. If we take 1.9 tons then we are uplifting additional 0.2 tons here? So for the above what will be the correct answer? Thanks in advance.
THERE IS ONLY ONE WAY TO DO THIS.... Which is sorry.... THAT IS the RIGHT WAY!!

MZFW+TakeOff Fuel
MLW + Trip (Takeoff Roll to Landing Roll or Burnoff - Taxi)
MTOW
Performance Limited Takeoff weight from RTOW Charts or Software

Calculate the above four numbers --->> Choose the Smallest of Them all --->> Smallest number - ZFW + Taxi Fuel = The amount of fuel you can carry

If the amount of fuel you can carry is fixed due to destination weather or enroute weather or any other reason in that case -->> Smallest Number - Fuel + Taxi Fuel = YOUR Max Zero Wt

Period ...
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Old 9th May 2018, 17:46
  #53 (permalink)  
 
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Originally Posted by vilas View Post
Goldenrivett
Far too many variations have got in the original question and we are going around in circles. IFR flight/VFR flight, Alternate required/not required/not available, remote destination all these situations have different fuel requirements, we can't discuss all in one breath. I was referring to Bergerie1. His RTOW calculation at Nairobi was incorrect. Period! Refusing some payload or passengers is always a bad idea but you have to do it many times otherwise Regulated Takeoff Weight will become a joke. You have no option unless you manipulate the BO. I do not want to repeat what I have already stated. I don't know how any one can justify doing unplanned low flying with passengers and a VIP/Semi VIP on board and claim a pat on the back.You can check weather and traffic but ask Sully he will tell you cannot check for birds. Then you burn fuel and along with it your diversion and claim privileges of a committed landing. And despite my quoting Airbus manual page number B737900er states EASA doesn't have landing weight limit. May be AIRBUS doesn't form part of EASA.
With my previous example of last minute load, can you say at what moment the RTOW has been violated?
Thank you for answering.
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Old 9th May 2018, 18:30
  #54 (permalink)  
 
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As long as the load sheet shows all weights below or equal to limit weights it's fine. As I have been pointing out some people relate RTOW only to takeoff. That's not so, even landing and GA performance at destination has influece on takeoff weight.
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Old 10th May 2018, 02:06
  #55 (permalink)  
 
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Originally Posted by vilas View Post
No! You can't. Arithmetically possible but not legally. (...) You cannot legally exceed that and then burn extra to get within MLW.
Ok! So a least everything is clear regarding this and no one plans to "cheat"
As for RTOW, if it is the equivalent of limitation due to other than structural with Boeing, you do not have to calculate anything. It specified in the OM-C (sometimes lower with wet runway) and it is the MLW you have to consider for the flight instead of the structural mlw.
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Old 10th May 2018, 10:12
  #56 (permalink)  
 
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Just to complicate things even further Tristars used to have a variable zero fuel weight.
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Old 10th May 2018, 10:56
  #57 (permalink)  
 
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Every aircraft has a variable zero fuel weight
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Old 10th May 2018, 12:05
  #58 (permalink)  
 
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Every aircraft has a variable zero fuel weight
A particular aircraft has only one ZFW. It is not variable but there can be some versions of the same model with different certified ZFW.

Last edited by vilas; 10th May 2018 at 12:18.
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Old 10th May 2018, 12:26
  #59 (permalink)  
 
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and it is the MLW you have to consider for the flight instead of the structural mlw.
I am unable to understand the meaning of this statement. What's the difference between MLW and structural mlw?
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Old 10th May 2018, 12:54
  #60 (permalink)  
 
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vilas,
What's the difference between MLW and structural mlw?
Some aircraft are restricted to a Maximum Planned Landing Weight at certain airfields due to performance.
e.g. B707 at old Heraklion airport in 70s was restricted to Structural MLW minus 2 Tons.
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