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Am I carrying too much reserve fuel??

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Hi there!On my recent SIN/LHR flight, I planned for EGCC Manchester as my alternate (usually on shorter flights I don't plan for any alternate providing the weather is fine + more than one runway available). I am wondering if this was perhaps unnecessary as the weather was fine at LHR. Could I have planned no alternate or somewhere on the way like EHAM or Gatwick?Anyhow, I was just wondering for those of you that see the odd real-world 744 flight plan, is this too much reserve fuel? (tonnes)4.000 contingency5.760 alternate4.200 holding (30 min)2.000 approach fuel (this is one qantas-specific)Total: 15.990This seems a little much? Typical figures from what I've seen seem to be around 12-13 tonnes usually.Any advice would be great?!CheersRudy


Rudy Fidao

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Hi Rudy,With lots of alternates en route you could maybe cut down on the CONT fuel.We use an En Route Alt ERA procedure for CONT fuel.CONT is either 5% of total trip fuel or if you have a suitable ERA in your case EHAM would be good 5% of the fuel from EHAM to LHR.Also If LHR weather is good you`d prabably have LGW or STN as destination alternates.If weather is looking bad and a diversion is more likely the a commercial alternate would be selected and the extra fuel carried.For example a normal alt for LHR on a good day would be STN Stansted needing say only 3000kg diversion fuel, as its unlikely you`ll go there,but if you did it costs the company extra time and money as we have no facilities there,but you save fuel.If a diversion is looking more likely eg LHR is below our fair weather company planning minima then a commercial alt like EGCC would be used as we have ground staff and equipment based there.Jon

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Well.. it depends on the route.. for long haul over oceans flight.. I usually plan for 21 - 22 tonnes.. in total.. but the FMC entry is around 17.1 tonnes for reserve.. as you only include 50% of the 45 minute holding fuel in that calculation.. Basically that way when you're holding and you hear the fuel warning come up on the EICAS.. you know you've used 50% of your holding fuel and really should be thinking about setting down..As for internal flights.. it is different I believe.. short flights give a reserve probably in the range of 10 - 15 tonnes.. in total.. I think the FMC entry is probably 10 or 11 taking only 50% of the holding fuel into account..... I imagine the reason over land flights use a lower reserve is because you've not got to worry too much about finding an airfield if you need to land for any reason.. and if there is a miss calculation and you burn more it's quickly spotted and you can land easily on route.. So the reserve is dependent more on the distance between alternates than anything else... And it is probably lower to save the over weight and fuel cost of the flight..Your planned landing weight.. should be.. your Zero Fuel Weight + ALL the contingency fuel.. so.. I would summarise like this.NO.. I don't think your figure is high if you're over ocean.. I'd expect a 20 tonne contingency and 17.1 as the entry to the FMC..There are differences in reserves for oceanic, long haul and inland flights.. 13 ish for inland and short flights with a 10 or 11 entry into FMC and 20 for oceanic with 17.1 entry..Hope that helpsCraig


Craig Read, EGLL

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Planned landing fuel on yesterdays LHR-MIA 9800KG,which is made of 1)diversion fuel KFLL 2) final reserve fuel 30 mins 3)cont fuel 4)1.4t of delay fuel.cheers Jon

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Rudy,if you forgot the extra qantas option you re right on the numbers you reported ... around 13 t ...but if the weather forecast was good over london i d better selected LGW or STN and then keep the extra fuel for hold london is well known for long holding ...!!!!

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>Hi Rudy,>>With lots of alternates en route you could maybe cut down on>the CONT fuel.We use an En Route Alt ERA procedure for CONT>fuel.>CONT is either 5% of total trip fuel or if you have a suitable>ERA in your case EHAM would be good 5% of the fuel from EHAM>to LHR.>Also If LHR weather is good you`d prabably have LGW or STN as>destination alternates.If weather is looking bad and a>diversion is more likely the a commercial alternate would be>selected and the extra fuel carried.>For example a normal alt for LHR on a good day would be STN>Stansted needing say only 3000kg diversion fuel, as its>unlikely you`ll go there,but if you did it costs the company>extra time and money as we have no facilities there,but you>save fuel.If a diversion is looking more likely eg LHR is>below our fair weather company planning minima then a>commercial alt like EGCC would be used as we have ground staff>and equipment based there.>>JonJon,the ERA is giving some fuel extra savings but this is not 5% giving by ICAO but 3% or 15 min the best of two of course ... maybe there is correction between RIF and ERA where the calculations for RIF is given from the new altn airport to final destination...i can check and made some scenarios to shwo you this...flightplanning is always a good task especially on long haul flight where forecasts are sometimes far from reality ....

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8.1.8.3En-route Alternate Procedure (Contingency Fuel)When the fuel uplift is insufficient to meet that required for the Standard Procedure, or it isconsidered that carriage of the full 5% contingency is not justified (see Note 5 below), it ispermissible to use an en-route alternate and carry the higher of (1) or (2) below:(1) 5% of the fuel required from the en-route alternate to destination.(2) 15 minutes at holding speed at 1,500 ft above the destination airfield in standard conditions(ISA) supported by data from the Company FCMP.Notes: (1) The weather conditions forecast for the selected en route alternate follow therequirements in paragraph 8.1.10.4(2).(2) The en route alternate must be chosen according to the requirements of the diagramshown on page A-8-29.(3) A check must be made at the Decision Point to establish that sufficient fuel isremaining to continue to destination. Should fuel be insufficient a landing should bemade at the en-route alternate or a closer destination planned.(4) The Decision Point will be the point at which the flight would deviate from thatplanned.(5) It is Company policy to use an ERA when flight planning so long as a suitableaerodrome is available for use.This is company specific which it would apear then is above ICAO requirements.Jon

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>8.1.8.3En-route Alternate Procedure (Contingency Fuel)>When the fuel uplift is insufficient to meet that required for>the Standard Procedure, or it is>considered that carriage of the full 5% contingency is not>justified (see Note 5 below), it is>permissible to use an en-route alternate and carry the higher>of (1) or (2) below:>(1) 5% of the fuel required from the en-route alternate to>destination.>(2) 15 minutes at holding speed at 1,500 ft above the>destination airfield in standard conditions>(ISA) supported by data from the Company FCMP.>Notes: (1) The weather conditions forecast for the selected en>route alternate follow the>requirements in paragraph 8.1.10.4(2).>(2) The en route alternate must be chosen according to the>requirements of the diagram>shown on page A-8-29.>(3) A check must be made at the Decision Point to establish>that sufficient fuel is>remaining to continue to destination. Should fuel be>insufficient a landing should be>made at the en-route alternate or a closer destination>planned.>(4) The Decision Point will be the point at which the flight>would deviate from that>planned.>(5) It is Company policy to use an ERA when flight planning so>long as a suitable>aerodrome is available for use.>>>This is company specific which it would apear then is above>ICAO requirements.>>Jonthanks Jon of course now it s more clear .... if we re talking about ops without giving any secret of course ... is it working for a flight let s say above 14 h ....???see you

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Yes the length of the flight doesnt matter to the amount of CONT fuel when using an ERA.If I had my way and most pilots would agree with me,we`d be doing what you guys do and be landing with 20T,but airlines simply won`t do that.Most flights plan to land with arount 10T, for every extra tonne of fuel you carry,dont forget, it will cost you between 150-250kg of extra fuel burn to carry it,depending on the aircraft weight.So planning to land with 20T instead of 10T would cost your airline 2.5T in wasted gas times say 40 flights a day for a long haul carrier? thats 100T per day times 365 days. thats a lot of profit lost.with the sim fuel is free so we can stick on as much gas as we like :-)jon

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Hi Jon and PhilThis is a very interesting post - thanks a lot for the information. It is really good to have professionals around on these forums!What sort of selection criteria do you have for enroute alternates?How often, if at all, would you fidn yourselves with an amount below what you planned to have at the decision point? Is there a little give and take in the deciding whether or not to divert? Could you sacrifice your CONT fuel?9.8 tonnes is pretty lean fuel planning - that's about as small as I've heard of (in my very limited experience).Thanks a lot too Craig and Ryan. It seems American carriers generally tend to carry more reserve fuel? I could be mistaken though.Cheers, and thanks again for your insightRudy


Rudy Fidao

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Hey Rudy,>What sort of selection criteria do you have for enroute>alternates?To be honest, it would depend what you want the alternate for. If you need to divert due to a mechanical failure or on-board emergency, I simply ask ATC for vectors to the nearest suitable airport. If it's for a fuel emergency, I would try to find an airport as close as possible to your original destination while having at least 7 tonnes of fuel remaining on landing.All in all, its very flexible. For example you may even want to divert for weather or stick it out and take the plunge through the bumps. You can basically choose any alternate you see fit for the type of emergency.>How often, if at all, would you fidn yourselves with an amount>below what you planned to have at the decision point? Is>there a little give and take in the deciding whether or not to>divert? Could you sacrifice your CONT fuel?By below my planned amount, do you mean just below or several tonnes off? I usually try to land with about 5 tonnes more than my reserve. So if I have 17 tonnes as my reserve, I would shoot for about 22 tonnes at landing. Since I get my fuel load right before my flight, I usually come in with about a +/-2 tonne error at most. If I do have unexpected headwinds or higher than expected temperatures, I'll drop my reserve to keep my INSUFFICIENT FUEL alarm from going off but I never go below a reserve of:8.7 when less than 1500nm from DES10.9 when more than 1500nm from DES>9.8 tonnes is pretty lean fuel planning - that's about as>small as I've heard of (in my very limited experience).I wouldn't worry if it's a short flight but if it's a long haul fight, I pretty much hope and pray that number goes up en route. Some airlines may still plan for this though as it would reduce costs.>Thanks a lot too Craig and Ryan. It seems American carriers>generally tend to carry more reserve fuel? I could be>mistaken though.I could be mistaken but I thought American carriers carried less of a reserve versus others like VIR or BAW.Ryan GamurotLucky to live Hawai'ihttp://www.precisionmanuals.com/images/forum/supporter.jpg


Ryan Gamurot
 

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The thing to remember here guys is that there is no reason why a long haul flight to an area with lots of available airports should carry more reserves than a short haul flight.For example yesterday I flew straight over Cork in Ireland on the way to Heathrow,I`m now in the identical position of the Aer Lingus CRK to LHR flight and have the same diversion options availabe to me.Ironically after talking about ERAs I got on the return flight from MIA yesterday to find that due to bad weather forecast in the UK and Ireland we didn`t have a ERA available but instead carried a full 5% CONT fuel which was 3900kg.We used to have a standard landing fuel of 10T on the fleet,but this is now variable and I`ve seen as low as 9.0T so far.The captain always has the right to add more fuel as he sees fit,and most times where we can see a valid reason we do.We are being hit over the head with the charge of carbon emmissions at the moment in aviation,especially in the UK so we as an airline are keen to show we save fuel where we can.But from a pilots point of view there is nothing worse than the feeling you dont have many options due to a lack of fuel.Legally you only need to land with Final reserve fuel which is typicaly 4-5T although no one would plan to land with that its still legal(thats the final touchdown fuel with diversion fuel burnt).Selection of an ERA for our company at least is done by drawing a circle around a point on the route centred on a distance from the destination of 20% of the whole route distance.Any airport within that circle and conforming to planning weather minima may be used as an ERA.Its not very often we have to consider going into the ERA airport, but I came clsoe a few months back on the way to KSFO when for a still unknown reason the aircraft burnt 3T more than was planned and I was about 300kg above having to go into KPDX to refuel.There is statements in the OPS manual that would allow us to continue past the ERA provided the destination airport has 2 or more independent runways and approaches, which SFO has,but anyone who knows it will know it wouldn`t take much to bring the whole of the bay area to a standstill. And so you have to think of all the weather and traffic factors when considering where and if to divert.cheersJon

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Guest benhoffman

Interesting.To answer your question, I personally would have a problem releasing that flight to land with 35,000lbs (~16t) of fuel, unless the weather is really, really bad or there is a good reason to carry that much then I think its uneconomic.UAL has a defined minimum which is 21,400lbs which does differ depending on the destination - eg some of the out of the way places like Saigon is 33,000lbs because they dont have a close alternate (we uses Bangkok)That reason for this minimum fuel is to protect the flight from some horrible, unforseen situation e.g. airport closure where we haven't listed an alternate through the Six Hour Rule.I think what Jon is referring to with the "enroute alternate" is called redispatch by the FAA, its just wonderful and saves lots of fuel and money.I'm not licensed on JAR/CAA Ops as I only know the FAA system (I can recite it in my sleep, blech!)It would really depend which system you're using (FAR/JAR/CAA/ICAO etc).With the FAA it works like this:Burn10% of burn TIME (ie 6 min/hr)Alternate (if required)30 minutes of holding at 1,500ft.Now, as Rudy said you can often land with 40,000lb (~20t) of fuel if the flight is really long.What United does is this: Lets say we're going from San Francisco to London, we'll .... a) find an enroute stop we can use (called INITIAL DESTINATION) which is Shannon or Dublin religiously for London:( Work out FAR requrirements to get to Shannonc) Find out how much fuel we have left over Shannond) Find out how much fuel we need to get to London from Shanoon to meet FAR, WX & Traffic etc e) See if we need any more fuel (eg required over Shannon is 50,000lb but we only have 23,000lb therefore, add 27,000lb)This means we burn a greater PERCENTAGE of fuel but burn LESS TOTAL fuel because we carry less, e.g. using redispatch we plan to land with 21,400lbs (about ~10t) which is enough to get to a predetermined alternate should we need one plus one hour of holding fuel.An altenate for the final leg is often not listed using the FAR Six Hour Rule - I dont think the CAA is that liberal but I'm not sure.This is done on nearly every international flight.Example: A few days the Dulles-Zurich flight (763) took off with 106,300lbs of fuel and planned to burn 94,700lbs to land with the minimum of 11,400lbs. Had we not used redispatch we'd be landing with around 20,000lbs because we'd have to specify an alternate a greater amount of 10% fuel.The FAA also provides a dual legal responsibility system where the Captain and Dispatcher are both responsible for all decisions; sure hope Europe gets the same.Hope this helps!

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>Interesting.>>To answer your question, I personally would have a problem>releasing that flight to land with 35,000lbs (~16t) of fuel,>unless the weather is really, really bad or there is a good>reason to carry that much then I think its uneconomic.>>UAL has a defined minimum which is 21,400lbs which does differ>depending on the destination - eg some of the out of the way>places like Saigon is 33,000lbs because they dont have a close>alternate (we uses Bangkok)>>That reason for this minimum fuel is to protect the flight>from some horrible, unforseen situation e.g. airport closure>where we haven't listed an alternate through the Six Hour>Rule.>>I think what Jon is referring to with the "enroute alternate">is called redispatch by the FAA, its just wonderful and saves>lots of fuel and money.>>I'm not licensed on JAR/CAA Ops as I only know the FAA system>(I can recite it in my sleep, blech!)>>It would really depend which system you're using>(FAR/JAR/CAA/ICAO etc).>>With the FAA it works like this:>>Burn>10% of burn TIME (ie 6 min/hr)>Alternate (if required)>30 minutes of holding at 1,500ft.>>Now, as Rudy said you can often land with 40,000lb (~20t) of>fuel if the flight is really long.>>What United does is this: Lets say we're going from San>Francisco to London, we'll .... >>a) find an enroute stop we can use (called INITIAL>DESTINATION) which is Shannon or Dublin religiously for>London>>:( Work out FAR requrirements to get to Shannon>>c) Find out how much fuel we have left over Shannon>>d) Find out how much fuel we need to get to London from>Shanoon to meet FAR, WX & Traffic etc >>e) See if we need any more fuel (eg required over Shannon is>50,000lb but we only have 23,000lb therefore, add 27,000lb)>>This means we burn a greater PERCENTAGE of fuel but burn LESS>TOTAL fuel because we carry less, e.g. using redispatch we>plan to land with 21,400lbs (about ~10t) which is enough to>get to a predetermined alternate should we need one plus one>hour of holding fuel.>>An altenate for the final leg is often not listed using the>FAR Six Hour Rule - I dont think the CAA is that liberal but>I'm not sure.>>This is done on nearly every international flight.>>Example: A few days the Dulles-Zurich flight (763) took off>with 106,300lbs of fuel and planned to burn 94,700lbs to land>with the minimum of 11,400lbs. >>Had we not used redispatch we'd be landing with around>20,000lbs because we'd have to specify an alternate a greater>amount of 10% fuel.>>The FAA also provides a dual legal responsibility system where>the Captain and Dispatcher are both responsible for all>decisions; sure hope Europe gets the same.>>Hope this helps! Ben,ERA is enroute alternate not reclearance ... relearance is RIF reclearance in flight but seems from what i read that Jon operations is a mix between ERA and RIF but again ICAO is one, then state rule ,then the company approved by authorities ... there is nothing on JAR ops about reserve as the state and authorities got the last word ...in Canada as in USA this is easier no ICAO but only CARs like FAR .... about responsible there are three countries in the world who share this China, USA (not all ops i think) and Canada with 705 ops (the biggest companies) sorry but the european dispatchs didnt have the same words as us ...see you

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