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Fuel planning

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Hi,Im trying to get the correct fuel calculations for a flight from Gatwick to Palma with alternate Airport being LEIB using the 737ng fuel planner please could someone tell me if this is correct as follows.Current flight conditionsWind- comming from northerly direction at 40 knots coldest temp is average at -55Trip distance is 737 milesTaxi fuel is 500 LbsAlt fuel is 3300 LbsHolding fuel 500 LbsMinium landing fuel is 4000 LbsTotal fuel being 16670 LbsWhat would be my missed approach fuel required?Many thanks Natalie french

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Hi,Im trying to get the correct fuel calculations for a flight from Gatwick to Palma with alternate Airport being LEIB using the 737ng fuel planner please could someone tell me if this is correct as follows.Current flight conditionsWind- comming from northerly direction at 40 knots coldest temp is average at -55Trip distance is 737 milesTaxi fuel is 500 LbsAlt fuel is 3300 LbsHolding fuel 500 LbsMinium landing fuel is 4000 LbsTotal fuel being 16670 LbsWhat would be my missed approach fuel required?Many thanks Natalie french
Natalie,That looks pretty good, but your holding fuel is only going to give you about 5-10 minutes. Not much. I'm not so sharp on JAR-OPS, but I think you're looking for something like 2600 pounds, giving you 30 minutes of hold. As for the missed approach, that should already be accounted for in your alternate fuel.

Matt Cee

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Natalie,That looks pretty good, but your holding fuel is only going to give you about 5-10 minutes. Not much. I'm not so sharp on JAR-OPS, but I think you're looking for something like 2600 pounds, giving you 30 minutes of hold. As for the missed approach, that should already be accounted for in your alternate fuel.
Thanks for the reply.Just one more question is my reserve fuel the altenate fuel and if so would I put this into the FMC (RES) as 33.0 or 3.30?Many thanksNatalie French

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Thanks for the reply.Just one more question is my reserve fuel the altenate fuel and if so would I put this into the FMC (RES) as 33.0 or 3.30?Many thanksNatalie French
Always thousands, no matter if it's in Kgs or lbs, so: 3.3

signed: José Luis

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Always thousands, no matter if it's in Kgs or lbs, so: 3.3[/qDoes the reserve fuel include your alternate, holding amd minimum landing fuel????

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Reserve is usually minimum landing fuel + alternate Fuel. Some airlines include holding fuel.


Joe Sherrill

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Guest mia

Hi Natalie;First of all I suggest you not using that Fuel planner, it

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Santiago, That "per minute" fuel usage is very interesting.Where did you get the numbers ?.I have made myself my own measurements for some aircraft of my fleet, and, translating the results to that "fuel per minute" rate, they are:Trip from LEVX to LEMD Distance 300 nm Crz alt FL290. Pax occupation 95%. Trip time (from takeoff roll to touchdown)PMDG 737-700. TOW=60000 Kg (86%)140 Pax (Pax+bagg=14000 Kg) (TO Fuel 8000 Kg) Trip time 56 min.Fuel at touchdown=5300 Kg Used fuel=2700 KgRate = 48.2 Kg per minute (0.344 Kg / pax / min)LevelD 767-300. TOW=125000 Kg (68%)250 Pax (Pax+bagg=25000 Kg) (TO Fuel 10000 Kg) Trip time 53 min.Fuel at touchdown=5020 Kg Used fuel=4980 KgRate = 93.9 Kg per minute (0.375 Kg / pax / min)PMDG 747-400. TOW=250000 Kg (63%)400 Pax (Pax+bagg=40000 Kg) (TO Fuel 30000 Kg) Trip time 51 min.Fuel at touchdown=20200 Kg Used fuel=9800 KgRate = 192.2 Kg per minute (0.480 Kg / pax / min)Any expert can say if those numbers are close to RW figures or not. But it can clearly be seen the low efficiency of the 744 for these kind of short hops.


signed: José Luis

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Guest mia

This is the best one, so I suggest you using this. I

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Santiago,I have used your calculations and they are spot on. Another question for you or anyone else regarding the FMC perf init page CRZ/WIND do you put into the fmc the strongest wind speed and wind genral direction encounted on route, also with the T/C OAT do you put the coldest temperture encounted on route into the FMC?Many thanks once again for sharing and explaining these subjects in great detail.Natalie French

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Guest mia

Natalie,Some information regarding FMC PERF INIT page:CRZ/WIND means Cruise Wind (Here you must put the expected wind -Direction and speed- when reaching your first CRZ level or Altitude), If your trip is short, you will probably use only one wind indicator on the WINTEMP charts. If you are planning a long trip, you must check all your expected cruise wind along your route. T/C OAT means Top of Climb Outside Temperature (Here you must put the expected temperature when reaching your first CRZ level or Altitude)How to do it? :( This is an example:Short Trip: KMIA - KTPA F260Check the proper WINTEMP chart/s for your route, as you can see, there are not available all CRZ altitudes/Levels WINTEMP charts. In this case you must Interpolate between twoo values:F260 is beween F180 and F300, so...F300:F180:Interpolation:Now you have your 3 values :( F260 CRZ/WIND -> 310

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Santiago,Once again thanks for explaining this in great detail this has helped me in planning my flights in greater detail.May I ask do you use vatsim for your airtraffic control or radar contact?Natalie French

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