Fuel tankering (including scenario)
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From: With Wonko, outside the Asylum.
Therefore two issues remain. 1. Does the aircraft's AOM preclude this sort of operation and 2. Is it economically worthwhile to do so?
Third, what do flight operations want? Tanking a lot inbound to a hub, for example, can be unhelpful if the deployment of airframes for the next day's operation has not been finalised; this is most true in a mixed long/medium/short haul operation. So, a brief call to ops is in order.
Fourth, the commander must decide whether, if there are additional hazards or elevated levels of risk from tanking, he is willing to accept them. If tanking onto a contaminated runway is permitted, then a crosswind might advise that adding to the landing weight is unwise whereas a reliably-forecast wind straight down the strip would not.
For me the decider on the 'contaminated' question is that contaminated figures are only ever 'best guess'; they provide none of the certainty that dry, damp, and wet do. I would not tank onto a contaminated runway for that reason alone.
Finally, I can't help having a feeling that the OP may be being asked to run before he can walk with confidence. It sounds like a somewhat obtuse question that's been posed; certainly clarification from the instructor would be in order, best in the form of: 'Here's your flight plan, here is the weather, here are the NOTAMs... What will you do?'. And anyhow, this is the sort of decision which will ultimately be made by an experienced commander, so asking someone who hasn't had the benefit of line flying experience is a little tough. Well done to the OP for coming here and asking in a good professional style.
Last edited by TheiC; 18th October 2015 at 18:01.
Only half a speed-brake
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From: Commuting not home
Munich, 3000+ m of LDA. ATR with 800 kgs extra tankering fuel. Runway is 50% covered with 1/2 inch wet snow. The OPF / PLOG shows company wants you to take it. Would you not?
care,
FD.
Thread Starter
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From: Bournemouth, occasionally in the air
Glad to see a good discussion has been made out of this, clearly a hot topic and one that varies between companies. I had a discussion with my instructor and he highlighted the following:
- The flight has not categorically been tankered with fuel.
- The report must take into consideration both the positives and negatives of deciding on tankering or not. For instance, deciding not to tanker has the positives of reduced fuel burn rate, but a negative is the aircraft may be in a long queue for refuelling.
- Discussion of cold soaked wing is an important factor, as is refuelling the aircraft in the morning (i.e de-ice still required)
Hopefully should make it a bit easier for myself, and with all the information from you chaps certainly helps. Basically, it's a case of "you make the decision".
- The flight has not categorically been tankered with fuel.
- The report must take into consideration both the positives and negatives of deciding on tankering or not. For instance, deciding not to tanker has the positives of reduced fuel burn rate, but a negative is the aircraft may be in a long queue for refuelling.
- Discussion of cold soaked wing is an important factor, as is refuelling the aircraft in the morning (i.e de-ice still required)
Hopefully should make it a bit easier for myself, and with all the information from you chaps certainly helps. Basically, it's a case of "you make the decision".
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From: With Wonko, outside the Asylum.
Munich, 3000+ m of LDA. ATR with 800 kgs extra tankering fuel. Runway is 50% covered with 1/2 inch wet snow. The OPF / PLOG shows company wants you to take it. Would you not?
Let me put it another way: landing on contaminated runways is more than usually hazardous. Is a solely financial imperative, affecting only the balance sheet and no other aspect of the operation, and then only marginally, good enough reason to further elevate the probability of something going wrong? On my watch, it isn't.
Last edited by TheiC; 20th October 2015 at 21:45.
Joined: Jun 2002
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From: Wor Yerm
TheiC - Is an ATR difficult to control when landing within limits on a contaminated runway? My experience of turbo-props is that they are the most pilot-friendly of all aircraft (ie. fixed wing; before one of our rotary friends wobbles up) when operating on slippery surfaces; but you have to respect the aircraft's limitations.
And let's return to the airport. EDDM is one of those airports that is generally open with wet runways, full width, full length BA Good or shut for snow clearance operations so they can bring it up to that standard. But if EGNV is your destination, you'll need a calendar for flight planning because snow clearance may take some time.
As for tanking values, I think common sense applies. I would also expect guidance in the form of a recommended tanking value. But I can also remember a certain captain who was so insecure they departed from virtually every airport with an additional three hours of fuel. It wasn't tanking, it was just under-confidence. But the effect of doing so often compromised that aircraft's payload on the next sector - over-tanking if you like.
PM
And let's return to the airport. EDDM is one of those airports that is generally open with wet runways, full width, full length BA Good or shut for snow clearance operations so they can bring it up to that standard. But if EGNV is your destination, you'll need a calendar for flight planning because snow clearance may take some time.
As for tanking values, I think common sense applies. I would also expect guidance in the form of a recommended tanking value. But I can also remember a certain captain who was so insecure they departed from virtually every airport with an additional three hours of fuel. It wasn't tanking, it was just under-confidence. But the effect of doing so often compromised that aircraft's payload on the next sector - over-tanking if you like.
PM
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From: Blighty (Nth. Downs)
Moving away briefly from the issue of contaminated runways (which don't necessarily apply in the OP's scenario), just a reminder of the two possible incentives for considering tankering in the first place:
1) problems with fuel availability at the first destination;
2) fuel more costly at the first destination than at the originating airfield.
In (2), the cost of carrying the fuel must be taken into account. Issues such as extra wear and tear on the engines, brakes and airframe are tough to quantify. Whether the increased fuel burn on the first sector negates the gain from the price difference can easily be settled, as I commented in an earlier post, using a graph of cost-difference versus sector-time (nowadays performed by computer).
1) problems with fuel availability at the first destination;
2) fuel more costly at the first destination than at the originating airfield.
In (2), the cost of carrying the fuel must be taken into account. Issues such as extra wear and tear on the engines, brakes and airframe are tough to quantify. Whether the increased fuel burn on the first sector negates the gain from the price difference can easily be settled, as I commented in an earlier post, using a graph of cost-difference versus sector-time (nowadays performed by computer).
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From: last time I looked I was still here.
Does MUC have a drive through de-icing rig; is it a remote de-icing area with manned spray hoses or is it at the gate? I doubt the latter at this newish extravagant airport. With the forecast temps you would expect to de-ice, so include that in the plan. Thus that cost is already a given so tanker max to save fuel cost. What tankering does do for you, if you can land with return fuel, is it reduces one more outside agency that could delay your departure in the early morning 1st wave. Some airports do not allow fueling & boarding at the same time. Load the pax and go the de-ice area snell. Everyone else will be clamouring for fuel & de-icing. The sooner you can get in the de-ice queue the better.
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From: Blighty (Nth. Downs)
RAT5,
You make some good points but - if refuelling is needed for an early-morning departure after a night-stop - it can often be done immediately after arrival (unless the whole airfield is about to close down for the night..,.
).
And what if the fuel price is lower at the night-stop airfield?
You make some good points but - if refuelling is needed for an early-morning departure after a night-stop - it can often be done immediately after arrival (unless the whole airfield is about to close down for the night..,.
).And what if the fuel price is lower at the night-stop airfield?
Only half a speed-brake
Joined: Apr 2003
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From: Commuting not home
Munich, 3000+ m of LDA. ATR with 800 kgs extra tankering fuel. Runway is 50% covered with 1/2 inch wet snow. The OPF / PLOG shows company wants you to take it. Would you not?
Let me put it another way: landing on contaminated runways is more than usually hazardous. Is a solely financial imperative, affecting only the balance sheet and no other aspect of the operation, and then only marginally, good enough reason to further elevate the probability of something going wrong? On my watch, it isn't.
regards, FD.
Joined: Jun 2000
Posts: 4,507
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From: last time I looked I was still here.
You make some good points but - if refuelling is needed for an early-morning departure after a night-stop - it can often be done immediately after arrival (unless the whole airfield is about to close down for the night..,. ).
And what if the fuel price is lower at the night-stop airfield?
I agree, but the topic is about tankering fuel into a night-stop where de-icing is expected the next morning.
And what if the fuel price is lower at the night-stop airfield?
I agree, but the topic is about tankering fuel into a night-stop where de-icing is expected the next morning.
Joined: Jan 2008
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From: Blighty (Nth. Downs)
Quote from RAT5 (my emphasis);
...the topic is about tankering fuel into a night-stop where de-icing is expected the next morning.
Piltdown Man and I seem to be alone in pointing out that de-icing in the morning may not be necessary, and is not predicated in the OP's assignment.
Quote from Ledhead27 (the OP):
I'm writing an assignment on fuel tankering and part of the brief includes the following:
"Discuss the issues with tanking when operating a return sector to a busy airfield in Germany (e.g. Munich Airport), with a late arrival and early departure the next morning. The flight is to take place in winter with the OAT at a constant -15°C. What issues need attention? What dangers to the aircraft could there be? Would there be a time during inclement weather when tanking would not be prudent?"
The assignment, which leaves many details unspecified, invites discussion of all the possible issues for and against tankering. Hence my reference to fuel prices.
The (admittedly unusual) fixed temperature of -15C overnight means the wx conditions are almost certainly overcast, and probably anticyclonic. So the atmosphere is likely to be very dry. IMO, precipitation and frost are unlikely but, as ever, cannot be ruled out.
...the topic is about tankering fuel into a night-stop where de-icing is expected the next morning.
Piltdown Man and I seem to be alone in pointing out that de-icing in the morning may not be necessary, and is not predicated in the OP's assignment.
Quote from Ledhead27 (the OP):
I'm writing an assignment on fuel tankering and part of the brief includes the following:
"Discuss the issues with tanking when operating a return sector to a busy airfield in Germany (e.g. Munich Airport), with a late arrival and early departure the next morning. The flight is to take place in winter with the OAT at a constant -15°C. What issues need attention? What dangers to the aircraft could there be? Would there be a time during inclement weather when tanking would not be prudent?"
The assignment, which leaves many details unspecified, invites discussion of all the possible issues for and against tankering. Hence my reference to fuel prices.
The (admittedly unusual) fixed temperature of -15C overnight means the wx conditions are almost certainly overcast, and probably anticyclonic. So the atmosphere is likely to be very dry. IMO, precipitation and frost are unlikely but, as ever, cannot be ruled out.
Joined: Apr 2008
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From: nowhere
Leaving the ATR's handling (narrow track, soft suspension, small control surfaces, criticality of loading and CG) to one side, no, I would not. That's about an 8% increase in the energy to be dissipated on landing, even if simply stopping straight ahead is the issue.
Let me put it another way: landing on contaminated runways is more than usually hazardous. Is a solely financial imperative, affecting only the balance sheet and no other aspect of the operation, and then only marginally, good enough reason to further elevate the probability of something going wrong? On my watch, it isn't.
Let me put it another way: landing on contaminated runways is more than usually hazardous. Is a solely financial imperative, affecting only the balance sheet and no other aspect of the operation, and then only marginally, good enough reason to further elevate the probability of something going wrong? On my watch, it isn't.
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From: With Wonko, outside the Asylum.
Was I not clear? No, I would not increase the degree of risk in a landing on a contaminated runway for a very marginal financial gain.
Last edited by TheiC; 29th October 2015 at 22:31.
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From: Queensland
If landing at MLW according to flight plan due to tankering, what happens if ATC gives direct tracking? This can sometimes be significant if expecting long STAR or SID, or perhaps you even get radar tracking to a relatively short final for a runway close to inbound track. If this happens close to destination there might not be the opportunity to increase fuel burn. I remember one time getting direct tracking after take-off at Casablanca to right base at Paris Orly! In such a case it was unnecessary to adjust fuel burn for max landing weight. Other past last minute track shortening was at Kai Tak when arriving from the north. Significant track shortening close to destination however, leaves less opportunity to adjust.
Other considerations are that there might be a possibility of last minute pax or freight additions. It would also be wise to allow for enough landing weight margin to enable the operator to fill the empty seats just before departure. A reasonable margin beats having to de-fuel or refuse extra pax! The same consideration is needed for the next day departure. Note that de-fuelling requires a tanker, probably empty, to collect unwanted fuel, and in my experience there could be a very long delay for this, resulting in loss of departure sequence or slot time that could impact the operation of the aircraft for the rest of the day.
Some captain adjustments to tankering fuel might appear without good reason but years of experience have influenced the decision.
The scenario is interesting and many good points have been raised.
It is noteworthy that some CX ops devote considerable resources to tankering fuel selection.
Other considerations are that there might be a possibility of last minute pax or freight additions. It would also be wise to allow for enough landing weight margin to enable the operator to fill the empty seats just before departure. A reasonable margin beats having to de-fuel or refuse extra pax! The same consideration is needed for the next day departure. Note that de-fuelling requires a tanker, probably empty, to collect unwanted fuel, and in my experience there could be a very long delay for this, resulting in loss of departure sequence or slot time that could impact the operation of the aircraft for the rest of the day.
Some captain adjustments to tankering fuel might appear without good reason but years of experience have influenced the decision.
The scenario is interesting and many good points have been raised.
It is noteworthy that some CX ops devote considerable resources to tankering fuel selection.
Joined: Apr 2008
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From: nowhere
We he a company policy for tankering ops where the landing weight must be a certain percentage below max to cover for shortcuts. But if it is a problem, get a hold to burn fuel or put the gear down early or something like that.
