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How much extra fuel can be uplifted?

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How much extra fuel can be uplifted?

Old 10th May 2018, 13:02
  #61 (permalink)  
 
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Originally Posted by vilas View Post
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.
A particular aircraft has one MAX ZFW but the actual ZFW is different on each flight. In that sense all aircraft have a variable ZFW.
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Old 10th May 2018, 13:05
  #62 (permalink)  
 
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Originally Posted by vilas View Post
I am unable to understand the meaning of this statement. What's the difference between MLW and structural mlw?
MLW takes into account the length of runway, density altitude, runway slope, braking action, go-around performance etc. it canít be more than structural but may well be less.
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Old 10th May 2018, 13:42
  #63 (permalink)  
 
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Originally Posted by vilas View Post
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.

I know. I fly once such aircraft. My comment was tongue in cheek.. he didnt say variable Maximum ZFW
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Old 10th May 2018, 15:29
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Some Boeings do have a variable ZFW. There will be a number such as 276,691 kg for the ZFW. However you can operate that aircraft up to a ZFW 288,031 kg as long as there is a reduction in the MTOW. The W&B manual will have a chart showing the trade off between higher ZFW and lower MTOW.
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Old 10th May 2018, 16:13
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Further to my post no 56 I meant Tristars used to have a variable MAX zero fuel weight. British Airtours was the airline.
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Old 10th May 2018, 17:10
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MLW takes into account the length of runway, density altitude, runway slope, braking action, go-around performance etc. it canít be more than structural but may well be less.
why not just call it landing weight? Max landing weight is a limitation that is structural. When you calculate the RTOW for that take off weight a certain landing weight results. We don't calculate max landing weight.
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Old 10th May 2018, 22:46
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Originally Posted by vilas View Post
why not just call it landing weight? Max landing weight is a limitation that is structural. When you calculate the RTOW for that take off weight a certain landing weight results. We don't calculate max landing weight.
Because it’s not the landing weight. The landing weight is the actual landing weight. The max landing weight is the max weight you could land at on the day, might be limited by structural limit or some lower limit due to a short runway.
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Old 11th May 2018, 00:01
  #68 (permalink)  
 
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Originally Posted by vilas View Post
why not just call it landing weight? Max landing weight is a limitation that is structural. When you calculate the RTOW for that take off weight a certain landing weight results. We don't calculate max landing weight.
There are 2 types of limitation: structural and performance.
Structural is about your aircraft and it is normally fix number (c.f FCOM)
Performance is about other than aircraft (rwy length/condition, obstacle, etc..) and it is variable (c.f Company Manual Route OM-C)
You chose the most restrictive applicable for your flight. Usually it is structural.
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Old 13th May 2018, 09:11
  #69 (permalink)  
 
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pineteam
I agree with Goldenrivett on this one. We discussed about it recently in this thread: https://www.pprune.org/questions/607...imum-fuel.html
What you discussed in that thread had many riders and a lot of confusion.
Imagine you are flying a commercial jet from A to B, flight time is 1h15m, A is your also your destination alternate and both airports are single runway only and weather is cavok on both airports.
Due to long taxi on the ground, you have burned more fuel than expected and once airbone you only have 5 min extra fuel
Since you mentioned an alternate, it is an IFR flight plan with alternate required. Then it requires usual fuel A to B+Cont+ to C+30min hold. You couldn't burn that during taxiing. There is an exception of not requiring a destination alternate in IFR but it has two conditions i.e. VMC approach and landing is possible and the destination has two runways. Since your destination has only one runway you cannot file an IFR flight plan. So I take it as a VFR flight plan which requires fuel A to B + 30min . If you discover after take off that you have only 5min extra then you simply land back. You would avoid everything that can happen at destination. Five minutes fuel is nothing by the time you reach there you may not have even that. Now coming to our thread, a President of a country should definitely be treated as more valuable than half a ton of vegetables. For heaven's sake you can't take law in your hand and do whatever you feel like.
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Old 13th May 2018, 10:35
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vilas,
If you discover after take off that you have only 5min extra then you simply land back. You would avoid everything that can happen at destination. Five minutes fuel is nothing by the time you reach there you may not have even that.
OK, please see thread # 37.
Consider two Flights A and B with no weather problems at their destinations.
A plans to go to airfield Z with airfield Y as the Alternate. B plans to go to Y with Z as the Alternate. Flying time between Y and Z is say 30 mins.

Both A and B arrive at their intended destinations at the same time and due to some airfield delays have to hold for say 20 mins.
Both are now down to their Reserve + Diversion Fuel. ATC advise of a further 5 mins delay, then both airfields will be open.
Do they continue to hold at their respective destinations or divert?

A) If they divert, then A and B will pass each other halfway between Z and Y and both will arrive at their respective Alternates with only Reserve fuel remaining.
B) If they both continue to hold at their respective destinations for a further 10 mins say, then both will land with Reserves + most of their Diversion Fuel remaining.

Which option would you take, A or B?
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Old 13th May 2018, 12:44
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Goldenrivette
Before I answer your question, in support of my post I will quote from IFALPA(ICAO) document you referred.
4.3.7.2 The pilot-in-command shall continually ensure that the amount of usable fuel remaining on board is not less than the fuel required to proceed to an aerodrome where a safe landing can be made with the planned final reserve fuel remaining upon landing.
So the moment you discover you only have 5minutes reserve instead of 30min you have to land back otherwise you violate this. What happens at destination won't save you. On takeoff you are supposed to be go minded and not in the air. Now coming to your question. Do a FORDEC and see for yourself. With further delay which cuts into alt+reserve regulation wise you should divert. Because if you are delayed still further or forced to divert later due to unforeseen events then you will land much short of regulatory minimum.

Last edited by vilas; 13th May 2018 at 14:10. Reason: correction
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Old 13th May 2018, 13:18
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Vilas, your quote only mentions final reserve, not alternate plus reserve. I don’t fly in your regulatory environment, but that quote itself doesn’t support what you are saying. Ditto for a mayday call, it’s a fuel mayday when you will land with less than fixed reserve, not when you will land with less than alternate plus reserve. Surely you can see that it is far safer to land at a good destination with lots of fuel instead of an alternate with minimum fuel. Why would you divert from a perfectly good airfield?
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Old 13th May 2018, 13:38
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You are Mayday Fuel if you expect to land at the nearest suitable airport with less than the final reserve (30 mn for jet). Example: your fob is 1h and you need 35 mn to fly to the nearest suitable airport.

You are Minimum Fuel if "committed to land at an airport" (alternate, destination or whatever) meaning you go to that airport and you expect to land at that airport with a fuel not less than the Final Reserve BUT you cannot accept any delay otherwise you would land with less than final reserve.
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Old 13th May 2018, 14:17
  #74 (permalink)  
 
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The quote is about post #69 which is in reply to another thread by pineteam where in a VFR flight plan there is no alternate fuel all you have is 30min extra. The rest deals with Golden's example which I agree I misquoted. In his case the situation will only arrive at the alternate if you divert later. I will correct my post. What is practical and what is regulatory sometimes does not tally and in dynamic environments things can rapidly change. Off course this example is hypothetical. The decision will also depend on what is your sequence in landing.
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Old 13th May 2018, 14:21
  #75 (permalink)  
 
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new_era
I corrected my post. I was dealing with two different scenarios caused the confusion.
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Old 13th May 2018, 14:57
  #76 (permalink)  
 
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vilas,
With further delay which cuts into alt+reserve regulation wise you should divert.
Interesting logic.
Q. Do you believe the act of diverting will guarantee there will be no "unforeseen events" at your diversion airfield?

What is practical and what is regulatory sometimes does not tally
I have found all regulations are logical and practical. Please give an example of one which is not.
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Old 13th May 2018, 16:33
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Example? The whole thread is about that. RTOW Ldg Wt Ltd? Practical is carry extra and burn it before landing but not allowed to do so unless you manipulate the BO. Why? Practical is to carry minimum fuel and burn alternate if you find weather OK and land. Not allowed legally. Believe me DGCA checks fuel in tanks airlines/pilots have been penalized. Why aviation while driving at red light see the traffic and jump. Not allowed.
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Old 13th May 2018, 21:02
  #78 (permalink)  
 
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vilas,
Practical is carry extra and burn it before landing but not allowed to do so unless you manipulate the BO.
You may load extra fuel up to your Take Off limited RTOW.
You have to consume surplus fuel (e.g. by holding) to ensure you are below maximum landing weight. Hence adjust the planned burn for the load sheet calculation.

Practical is to carry minimum fuel and burn alternate if you find weather OK and land. Not allowed legally.
When operating to an isolated airfield (say Seychelles), inflight fuel management allows use of decision point.
"Decision Point: The nominated point, or points, en-route beyond which a flight can proceed provided defined operational requirements, including fuel, are met. If these requirements cannot be met the flight will proceed to a nominated Alternate Aerodrome.
Note 1: The operational requirements required to be met are specified by the operator and approved, if required, by the State.
Note 2: Once past the final Decision Point the flight may not have the ability to divert and may be committed to a landing at the destination aerodrome."

Bergerie 1, in his VC10, may have elected to make his decision point say 10,000 ft on the descent. Weather at destination was CAVOK, he was number one for the approach and thus a successful landing was assured. If he decided Landing was not assured, then he could easily have diverted to Mombassa with all Reserves intact.
He was overweight for a straight in approach, so elected to "hold" by doing a visual circuit around the Island and landed below Max Landing weight at his destination.

Which bits are "Not allowed legally"?
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Old 13th May 2018, 23:20
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Originally Posted by vilas View Post
pineteam
What you discussed in that thread had many riders and a lot of confusion.
It seems pretty clear to me, except I do not understand so many pilots are so eager for extra fuel.

Since you mentioned an alternate, it is an IFR flight plan with alternate required. Then it requires usual fuel A to B+Cont+ to C+30min hold. You couldn't burn that during taxiing. There is an exception of not requiring a destination alternate in IFR but it has two conditions i.e. VMC approach and landing is possible and the destination has two runways. Since your destination has only one runway you cannot file an IFR flight plan. So I take it as a VFR flight plan which requires fuel A to B + 30min . If you discover after take off that you have only 5min extra then you simply land back. You would avoid everything that can happen at destination. Five minutes fuel is nothing by the time you reach there you may not have even that. Now coming to our thread, a President of a country should definitely be treated as more valuable than half a ton of vegetables. For heaven's sake you can't take law in your hand and do whatever you feel like.
You have so many wrongs here, and in most of your replies. You seriously need to read up on this, not joking.

The fuel in your PLANNING phase needs to be in your tanks at pushback, this is taxi,trip,cont,alt,+final.

You can do a continues inflight replanning, just always land with final reserves. Where you land does not matter.

If you return to departure airport because you are 5 min short, I hope the DFO will call you in for tea no biscuits. If you divert on a cavok day because you are down to final+alt, youíll get another invite for tea!

All these rules are pretty simple, and been the same in all the different CAAs I have worked under, its simple and straightforward, so donít make it complicated.

happy landings.. also on final fuel.




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Old 14th May 2018, 06:21
  #80 (permalink)  
 
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Goldenrivette
We are going round in circles. I hope you get the facts right. You can disagree if I express an opinion but not with the regulations
You may load extra fuel up to your Take Off limited RTOW.
You have to consume surplus fuel (e.g. by holding) to ensure you are below maximum landing weight. Hence adjust the planned burn for the load sheet calculation.
Read my post #24 and #38. You are an airbus pilot read page 74 of PTM. RTOW also contains Ldg Wt Ltd takeoff weight. So you cannot load more than that. You are doing manipulation with BO not for load sheet calculation but to stay within the legal Ldg. Wt. limited RTOW.
Bergerie1 filed Mombasa as an alternate so it was not isolated airfield case and all your explanation for isolated airfield is irrelevant and not valid.
Which bits are "Not allowed legally"?
virtually everything. Lifting Pay load and raising ZFW which put RTOW beyond limit ( read post #38). Burning alternate fuel. Doing unplanned low flying at 500ft with passengers and if I may say a VIP on board. If slammed with sea gulls I can assure you, he wouldn't have got Sully's welcome. And Seychelles has or had only one runway. If this is common sense then I am happy I don't have that. Actually I should ask what is legal in this flight?
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