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How much extra fuel can be uplifted?

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How much extra fuel can be uplifted?

Old 7th May 2018, 02:26
  #21 (permalink)  
 
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vilas, Feather44
If you change the trip fuel on the loadsheet you solve the legal issue. But then you have to burn it in real.
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Old 7th May 2018, 04:10
  #22 (permalink)  
 
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Feather
you're absolutely correct. I am not suggesting OW landing that is also a limitation just trying to show the incorrectness of planning OW landing RTOW. And new_era I already said that BO needs to be adjusted. The one that got away doesn't make anything legal.

Last edited by vilas; 7th May 2018 at 04:55.
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Old 7th May 2018, 04:39
  #23 (permalink)  
 
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new era, Yes, I understand your point.
Unfortunately, I don't believe we are allowed to round numbers on our own.
I suppose it must be documented. Which means you need a new CFP to show the new figures for fuel trip or taxi fuel.

Of course not doing so will probably go unnoticed. Until a poop hit the fan and dgca start to investigate.
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Old 7th May 2018, 05:16
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Important thing to understand is that RTOW Ldg Wt Ltd. is a regulatory takeoff weight limitation and it legally controls takeoff weight it has nothing to do with what weight actual landing is carried out. This is not an arithmetical exercise.
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Old 7th May 2018, 05:57
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I'm very interested about the RTOW Ldg Wt Ltd you are talking about. Can you please elaborate by giving an example?
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Old 7th May 2018, 06:22
  #26 (permalink)  
 
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vilas,

As I remember it (it was a long time ago) it was only necessary to sign a section on the load sheet declaring that the excess would be burnt off before landing. Perhaps the law has changed or perhaps captains were allowed more discretion in those days.
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Old 7th May 2018, 08:48
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vilas,
Important thing to understand is that RTOW Ldg Wt Ltd. is a regulatory takeoff weight limitation and it legally controls takeoff weight
Correct. But you may increase the planned burn by choosing to fly faster, lower or even holding to ensure Landing Weight is not exceeded.
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Old 7th May 2018, 09:04
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As you say..there will be a legal requirement that one should not produce a load sheet with illegal landing weight figures. OTOH even in these days of the computer saying “no” upstream of loadsheet production there are ways of generating a Trip Fuel that produces a legal landing weight figure.
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Old 7th May 2018, 11:39
  #29 (permalink)  
 
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Bergerie1

If you required a certain amount of fuel to get to the Seychelles and then have enough to divert to Mombasa and this put you overweight at the Seychelles surely by burning off fuel to get to the landing weight at Seychelles you would be below the legal requirement to reach Mombasa has a last minute incident closed the Seychelles airport.

I suspect the only legal solution would have been to reduce the traffic load ex Nairobi.
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Old 7th May 2018, 11:54
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bar none,

The weather was CAVOK, and no other traffic - I checked with ATC. Yes, I agree my decisons may have been legally marginal but they were safe.
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Old 7th May 2018, 12:15
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Originally Posted by Bergerie1 View Post
bar none,

The weather was CAVOK, and no other traffic - I checked with ATC. Yes, I agree my decisons may have been legally marginal but they were safe.
unfortunately common sense has now left the building.
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Old 7th May 2018, 12:24
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surely by burning off fuel to get to the landing weight at Seychelles you would be below the legal requirement to reach Mombasa has a last minute incident closed the Seychelles airport.
Why is holding to Land at Seychelles with min reserve + lots extra fuel at Max Landing weight less legal than diverting to Mombassa and arriving with min reserves?
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Old 7th May 2018, 12:30
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Golden Rivet,

I totally agree! This conversation has become ridiculous - all common sense has gone out of the window.
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Old 7th May 2018, 13:10
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Hi Bergerie1,
The rules sill make common sense. It's just some crew's flawed interpretation.
We used to operate to BDA with Island Reserve fuel plans. i.e. Arrive overhead BDA with the ability to hold for 90 mins and no where else to go.
Minimum Fuel Required - No Destination Alternate / 'Isolated Airfield'
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Old 7th May 2018, 13:50
  #35 (permalink)  
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We can plan to burn extra fuel BUT legally it can not be documented as Vilas said. Common sense or not, a flight can not depart with a flight plan that says OW landing at destination. Boeing fctm has a different section on OW ldg and it will do fine but that does not mean we can plan overweight landing or plan to burn excess fuel BEFORE departure deliberately in order to achieve ldg wt limitation at destination. If you plan to burn more than normal burn off by choosing different altitude or speed/mach etc then the additional burn off gets to add in the total burn off in the flight plan so I dont know how its possible to document the additional burn off for legal purpose
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Old 7th May 2018, 15:40
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Goldenrivett,

Yes we did that too - many times. And this thread has made me think back a bit. I forget the likely fuel figures I would have had to play with - lost in the mists of time I fear! I guess I would have had to burn off about 20 to 30 mins of fuel after arriving at the field. Whether I would have had the equivalent of Island Reserve I don't recall, but it must have been close to the required amount.

What concerns me about the discussion on this thread is the lack of lateral thinking. Is everyone these days blinkered by strict rules, SOPs and overbearing managements?
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Old 7th May 2018, 16:29
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Bergerie1,

Itís a bit like the story of 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?

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.
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 is safer? (Both are legal).
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Old 7th May 2018, 18:49
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Bergerie1
Is everyone these days blinkered by strict rules, SOPs and overbearing managements?
Rules, SOPs and overbearing management are different things. When it comes to regulatory requirements there is simply no option but to follow them. Breaching SOP and management decisions may cause a reprimand or at worst loss of that job but you still have the license you can go somewhere else. Person who operates within regulatory requirements is not blinkered but is disciplined and knowledgeable. I have not seen any rule that allows you to simply sign that you will burn the extra and breach RTOW requirements.
New_era I don't know which aircraft you fly but if it is airbus then open the performance training manual and you will see that there two requirements at destination that limit your take off weight. It is clearly written on page 74: MTOW is the lowest of:
1. Max Take off weight due to limiting landing weight at destination.
2. Max take off weight due to limiting go round weight at destination.
3. Limiting performance take off weight( obtained with Regulated Takeoff Weight charts.)
All the conditions are simultaneously applicable. You cannot violate the first two for take off by saying we will manage later for landing.
Yes! you can cheat by showing higher fuel burn. But I don't see any logic in picking up more fuel only to burn by flying low. Especially in the original post for extra 200kgs.

Last edited by vilas; 7th May 2018 at 18:59.
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Old 7th May 2018, 23:39
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You don’t do it so you can take extra fuel, you do it when your payload is higher than expected or perhaps you got over-fueled. Given a choice of offloading a couple of pax, de-fueling the aircraft, or revising the burn to make the load sheet work, I’d take the latter.
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Old 8th May 2018, 01:23
  #40 (permalink)  
 
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Vilas,

Thank you very much for explanation. I’m on the 737NG. I got your point now about the limitation. Yes we do have also these performance limitations (field length, go around, obstacle, …) and the structural limitation.

Please! Please! It is not about cheating or doing illegal thing.

As AerocatS2A said it is in the case that refueling is completed and you expect to land at mlw (performance or structural)

Consider my following example (original post figures) considering ONLY structural limitaion:

zfw…61

fob…15.4 (13.5 +1.9)

tow…76.4

trip….10 (FL350)

ldw…66.4

Then you have last minute 4 pax (90 x 4 = 360 kgs) Is it arithmetically and legally possible to take them? YES

How? Change to cruise at FL 310. Rule of thumb, if you fly 4,000 ft below the optimum you will burn roughly 5% more fuel (FPPM p2.1.1)

Figures become:

zfw…61.4 (+4 pax)

fob…15.4 (13.5 +1.9)

tow…76.8

trip….10.5 (FL310)

ldw…66.3 (even less than mlw)



Now please tell me, where is the cheating, where is the illegal thing on it.

Last edited by new_era; 8th May 2018 at 01:25. Reason: wrong number
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