Fuel Planning Question

[falk781 0]

This is weird.. but maybe not. I planned a real world flight from Seoul - Atlanta with a corrected NAM of 6258. I loaded it with 64,620 in PAX and 73,500 in Cargo with a ZFW of 532,208. I calculated 325,141 lbs of fuel @ FL 370 and a 40 Knt tail wind. For some reason, it was saying that I was going to run out of fuel over St Louis.At only 6258 miles, is this correct? Is the table used for fuel planning based on Max ZFW? Even with Zero PAX and Cargo, it was saying I would land with about 9.1 left in the tanks... doesn't this seem low? Seems like it should be able to go further?

[Shmiffy 0]

This is weird.. but maybe not. I planned a real world flight from Seoul - Atlanta with a corrected NAM of 6258. I loaded it with 64,620 in PAX and 73,500 in Cargo with a ZFW of 532,208. I calculated 325,141 lbs of fuel @ FL 370 and a 40 Knt tail wind. For some reason, it was saying that I was going to run out of fuel over St Louis.At only 6258 miles, is this correct? Is the table used for fuel planning based on Max ZFW? Even with Zero PAX and Cargo, it was saying I would land with about 9.1 left in the tanks... doesn't this seem low? Seems like it should be able to go further?

Did you enter the winds aloft in the RTE DATA section of the LEGS Page?The 744 will calculate (very accurately) the fuel on arrival if you can enter the winds aloft. It helps if you have the SID and STAR in.To source the winds aloft data, either plan your flights using Flight Operations Centre with a WX Subscription, or run your flight plan through Active Sky and use the winds it gives you from there.CheersPaul

[falk781 0]

Did you enter the winds aloft in the RTE DATA section of the LEGS Page?The 744 will calculate (very accurately) the fuel on arrival if you can enter the winds aloft. It helps if you have the SID and STAR in.To source the winds aloft data, either plan your flights using Flight Operations Centre with a WX Subscription, or run your flight plan through Active Sky and use the winds it gives you from there.CheersPaul

Since the wind correction is factored into fuel calculation, I.E. obtaining the corrected nautical air miles, does it matter if you put the wind data into the FMC? To answer your question, I didn't put the wind data into the FMC and the SID and STAR was programmed in. Seems as though it wouldn't pay to fly the flight with that little amount of pax and cargo?Is the fuel table for the 744 assuming a max ZFW?

[phil747fan 14]

you re correct on your number but you cannot fly it.what about reserve, contingency, hold ???!!!! if you remove the pax and load weights you re not gaining that much ...you should reduce your payload and pax numbers at first, then watching about your flight levels you cannot start at fl370 try 2000 ft step then for your speed try LRC and MRC or cost index 0 it will certainly help a little.and as suggested try to input the wind prediction (forecast) if you have the route i can generate for you some numbers via foc to show some options ...!!!see youphil

[falk781 0]

you re correct on your number but you cannot fly it.what about reserve, contingency, hold ???!!!! if you remove the pax and load weights you re not gaining that much ...you should reduce your payload and pax numbers at first, then watching about your flight levels you cannot start at fl370 try 2000 ft step then for your speed try LRC and MRC or cost index 0 it will certainly help a little.and as suggested try to input the wind prediction (forecast) if you have the route i can generate for you some numbers via foc to show some options ...!!!see youphil

I've programmed all of the wind calculations in using ASX. I've also emptied the plane completely and it still shows up with 0 fuel at the destination. Using corrected NAM and the table, the only way I found to get it to work is 2/3 PAX, empty cargo and max fuel. I was wondering why I can't come up with the correct fuel using the table in the manual? The actual miles are 6941, but with an average tail wind of 64, I get a correted NAM of 6035. If I use the actual miles flown and calculate using the table, I have about 23,400 left in the tank.Would you agree with using the actual miles flown vs the corrected for a flight this long?Here is the flightplan --SEL G597 LANAT Y51 SAMON Y513 KMC GOC OTR4 PABBA OTR5 CALMA 4400N 16000E 4600N 17000E 4800N 18000E 4900N 17000W 5000N 16000W 5000N 15000W 4900N 14000W PRETY TAMRU SEFIX CASDY J500 YVR J52 GEG J136 BIL J151 STL J45 PLESS Q19 BNA RMG3 Average tail wind @ 64, step climb using 2000. Intial altitude @ FL310. Using LRC.

[Shmiffy 0]

I've programmed all of the wind calculations in using ASX. I've also emptied the plane completely and it still shows up with 0 fuel at the destination. Using corrected NAM and the table, the only way I found to get it to work is 2/3 PAX, empty cargo and max fuel. I was wondering why I can't come up with the correct fuel using the table in the manual? The actual miles are 6941, but with an average tail wind of 64, I get a correted NAM of 6035. If I use the actual miles flown and calculate using the table, I have about 23,400 left in the tank.Would you agree with using the actual miles flown vs the corrected for a flight this long?Here is the flightplan --SEL G597 LANAT Y51 SAMON Y513 KMC GOC OTR4 PABBA OTR5 CALMA 4400N 16000E 4600N 17000E 4800N 18000E 4900N 17000W 5000N 16000W 5000N 15000W 4900N 14000W PRETY TAMRU SEFIX CASDY J500 YVR J52 GEG J136 BIL J151 STL J45 PLESS Q19 BNA RMG3 Average tail wind @ 64, step climb using 2000. Intial altitude @ FL310. Using LRC.

23,400 - Is that Kg's or Lb's?Let me know what the ZFW is that you were thinking about, and i'll do the same as Phil747Fan and run a couple of FOC Plots for you.CheersPaul

[falk781 0]

23,400 - Is that Kg's or Lb's?Let me know what the ZFW is that you were thinking about, and i'll do the same as Phil747Fan and run a couple of FOC Plots for you.CheersPaul

I'm doing everything in LBS.... ZFW us 459788.... at this rate with the selected wind calcs, the table says I need 258300 +24000 MLF, 8000 Alternate, 9000 Contingency for a total of 301879...So in summary -Using actual flight mileage with contingencies - 356,600Using Corrected NAM with contingencies - 301,879Thats a delta of 54721.... quite a huge gap???

[Shmiffy 0]

Okay, i've tried running a plan through Flight Operations Centre using a BAW 744 with the RB211 Engines. It's definately a load limiting flight, apologies for all the weights, being a Brit I use KG's.

BRITISH AIRWAYS VIRTUAL - COMPANY FLIGHTPLAN	   SEQ002	  RLS001		    BAW9999  RKSIKATL.001	   ETD 01.00Z   09.11.28							   Aircraft B744-RB21-BAW	  Registration GBYGE								   TO SLOT   ......															     222.3	 ZFW   .... 01.00  OUT ....  TNKS ....								  370.7	 TOW   ....		OFF ....  USED ....								  234.3	 LAW   ....		 ON ....  LEFT ....								  6075	  ESAD  .... 13.40   IN ....  ACH FL ....							    6809	  DIST  NCR  CRSM   110  GCI  1050 BIAS											   PROFILE:																	    AGSUS/F310 - 44E60/F330 - 50N50/F350 - TAMRU/F370 - BIL/F390  TIF	...... 136.42	 12.14  6075	W/C T062							    DIVF   ...... 0.40	   00.15		  ALT*								    F/RES  ...... 5.50	   00.30												  C/FUEL ...... 0.00															  HOLD   ...... 0.00															  RRES   ...... 5.00	   00.27												  TAXI   ...... 1.00															  EROPS  ......																   REQ	...... 148.32	 13.26			  DIVERT  0.40					    EXTRA  ...... 1.10						  RTE RES 5.00					    TANKS  ...... 149.42	 PLAN REM 12.0	  TOT RES ......					   ALT SUMMARY	FUEL	TIME   FL				 DIV SPD SCHED				  ALT*		   0.40	00.15					 Cost Index 0				  																																																												  ROUTE:																		  SEL1A-SEL / G597-LANAT / Y51-SAMON / Y513-KMC / DCT-GOC /  OTR4-PABBA / OTR5-CALMA / DCT-44E60 / DCT-48E70 / DCT-50E80 /  DCT-50N70 / DCT-50N60 / DCT-50N50 / DCT-49N40 / DCT-PRETY /  DCT-TAMRU / DCT-SEFIX / DCT-CASDY / J500-YVR / J52-GEG /  J136-BIL / J151-STL / J45-PLESS / RMG3-RMG / (I10-SCARR)   NOTES : - Fuel Bias rised to 1050 - Route exeeds 105 per cent of GC ! - FLIGHT PLANNED WITHOUT ALTERNATE: - Holding Fuel (15 Min.) added as Alternate-Fuel - UWX DATA FILES IN USE : 20091128.00U / 20091128.06U / 20091128.12U - STOPS/EROPS NOT CALCULATED  [FF] FLIGHTPLAN:																	 AWY	POS   FREQ   FL   MT  DIST  TME  ETO  ATO  ETA  EET   FUEL  FOB   RFU  ------------------------------------------------------------------------------		RKSI						0.00 ..../..../..../0.00  0.00  /.....148.4 SEL1A  SEL   115.50 F040 104 023.5 0.03 ..../..../..../00.03 1.34  /.....147.0 G597   ENKAS		F080 086 022.0 0.03 ..../..../..../00.06 2.58  /.....145.8 G597   KARBU		F100 086 013.9 0.02 ..../..../..../00.08 3.33  /.....145.1 G597   JINBU		F180 087 044.6 0.06 ..../..../..../00.14 5.73  /.....142.6 G597   KAE   115.60 F190 087 008.2 0.01 ..../..../..../00.15 6.11  /.....142.3 G597   SORKA		F230 129 030.2 0.04 ..../..../..../00.19 7.44  /.....140.9 * TOC  AGSUS D-010				 G597   AGSUS		F310 129 078.3 0.09 ..../..../..../00.28 10.20 /.....138.2 G597   LANAT		F310 131 042.6 0.04 ..../..../..../00.32 11.17 /.....137.2 Y51	SAMON		F310 100 149.1 0.14 ..../..../..../00.46 14.35 /.....134.0 Y513   KMC   112.00 F310 091 092.5 0.09 ..../..../..../00.55 16.30 /.....132.1 DCT	GOC   115.30 F310 090 191.4 0.19 ..../..../..../01.14 20.38 /.....128.0 OTR4   TOPOS		F310 091 103.0 0.10 ..../..../..../01.24 22.56 /.....125.8 OTR4   PABBA		F310 092 072.9 0.07 ..../..../..../01.31 24.09 /.....124.3 OTR5   ADNIP		F310 067 157.9 0.16 ..../..../..../01.47 27.36 /.....121.0 OTR5   CALMA		F310 069 185.7 0.19 ..../..../..../02.06 31.22 /.....117.2 DCT	44E60		F330 061 500.3 0.46 ..../..../..../02.52 40.50 /.....107.9 DCT	48E70		F330 059 481.0 0.53 ..../..../..../03.45 50.49 /.....97.93 DCT	50E80		F330 068 411.7 0.47 ..../..../..../04.32 59.47 /.....88.96 DCT	50N70		F330 079 385.9 0.43 ..../..../..../05.15 67.58 /.....80.84 DCT	50N60		F330 076 385.9 0.41 ..../..../..../05.56 75.21 /.....73.21 DCT	50N50		F350 072 385.9 0.32 ..../..../..../06.28 81.03 /.....67.40 DCT	49N40		F350 078 394.4 0.40 ..../..../..../07.08 87.98 /.....60.44 DCT	PRETY		F350 069 297.7 0.35 ..../..../..../07.43 93.89 /.....54.53 DCT	TAMRU		F370 072 064.7 0.07 ..../..../..../07.50 95.22 /.....53.20 DCT	SEFIX		F370 073 162.3 0.20 ..../..../..../08.10 98.47 /.....49.96 DCT	CASDY		F370 059 109.6 0.14 ..../..../..../08.24 100.68/.....47.74 J500   YVR   115.90 F370 070 032.7 0.04 ..../..../..../08.28 101.32/.....47.10 J52	SHUKA		F370 089 042.7 0.05 ..../..../..../08.33 102.13/.....46.29 J52	TWISP		F370 094 089.8 0.11 ..../..../..../08.44 103.82/.....44.60 J52	GEG   115.50 F370 094 105.9 0.13 ..../..../..../08.57 105.81/.....42.62 J136   HILIE		F370 073 038.1 0.04 ..../..../..../09.01 106.52/.....41.90 J136   MLP   117.80 F370 077 042.5 0.05 ..../..../..../09.06 107.30/.....41.12 J136   HLN   117.70 F370 087 159.6 0.17 ..../..../..../09.23 110.01/.....38.41 J136   BIL   114.50 F390 092 146.5 0.15 ..../..../..../09.38 112.46/.....35.96 J151   RAP   112.30 F390 099 263.0 0.28 ..../..../..../10.06 116.78/.....31.64 J151   ONL   113.90 F390 101 209.8 0.24 ..../..../..../10.30 120.41/.....28.01 J151   DSM   117.50 F390 094 233.5 0.27 ..../..../..../10.57 124.45/.....23.97 J151   JAVAS		F390 129 056.1 0.07 ..../..../..../11.04 125.41/.....23.01 J151   CHASY		F390 133 005.9 0.01 ..../..../..../11.05 125.51/.....22.91 J151   SKBOZ		F390 133 009.4 0.01 ..../..../..../11.06 125.67/.....22.75 J151   COLIE		F390 135 024.8 0.03 ..../..../..../11.09 126.10/.....22.32 J151   TWAIN		F390 134 050.0 0.06 ..../..../..../11.15 126.95/.....21.47 J151   STL   117.40 F390 137 066.1 0.08 ..../..../..../11.23 128.08/.....20.34 J45	PLESS		F390 130 095.4 0.11 ..../..../..../11.34 129.69/.....18.73 RMG3   BNA   114.10 F390 133 148.5 0.17 ..../..../..../11.51 132.09/.....16.33 RMG3   DRAKK		F390 149 028.0 0.03 ..../..../..../11.54 132.55/.....15.87 * TOD  NEUTO D-029				 RMG3   NEUTO		F310 150 047.9 0.05 ..../..../..../11.59 133.54/.....14.89 RMG3   RMG   115.40 F150 150 065.4 0.09 ..../..../..../12.08 134.14/.....14.28 I10	PENCL		F050 146 038.9 0.06 ..../..../..../12.14 134.42/.....14.00 I10	ZMANN		F040 094 003.1 0.01 ..../..../..../12.15 134.45/.....13.98		KATL						0.00 ..../..../..../12.14 136.4 /.....12.00 [FF]  WAYPOINTS AND WINDS : ENROUTE ICAO  FREQ   LATITUDE LONGITUDE MAG	WD

[falk781 0]

So based on my conversion of what your program ran, it says you need a total of 300,000 lbs? If so, my original calculation with Corrected NAM was 301879 lbs. The FMC says no way.I'm crusing right now at .84, FL 310 and the ending fuel is showing 54,000 LBS. If this is true, we are still 57,300 lbs difference and I would be landing with -3000 lbs...Do you agree with this and any thoughts?By the way.... CPA 35 on Servinfo if you're looking

[Shmiffy 0]

So based on my conversion of what your program ran, it says you need a total of 300,000 lbs? If so, my original calculation with Corrected NAM was 301879 lbs. The FMC says no way.I'm crusing right now at .84, FL 310 and the ending fuel is showing 54,000 LBS. If this is true, we are still 57,300 lbs difference and I would be landing with -3000 lbs...Do you agree with this and any thoughts?By the way.... CPA 35 on Servinfo if you're looking

Hi Scott, i'm an IVAO kinda guy so got rid of servinfo in favour of The IVAO Eye a long time ago :( Anyway, It's a Load Limited flight, so the best ZFW i could get, less a bit of comfort factor was 222,300Kg which works out as roughly 490087.60 Lb's using a web based conversion calc.In the FP That i ran above, there is no alternate, but i requested about 12,000Kg's (26400 lbs) to be the Remaining Fuel, which is about what i would plan for for a KLAX EGLL trip including divert to EGKK about 30 Miles down the road.So, based on an 01:00Z Departure (about 10 Mins time), you would need 149,420 Kg's of Gas, or about 428622.73 lb'sNot sure if that responds to your point, i hope it does, but keep firing away....http://manuelsweb.com/kg_lbs.htm is the conversion calc i used BTW...CheersPaul

[falk781 0]

Hi Scott, i'm an IVAO kinda guy so got rid of servinfo in favour of The IVAO Eye a long time ago :( Anyway, It's a Load Limited flight, so the best ZFW i could get, less a bit of comfort factor was 222,300Kg which works out as roughly 490087.60 Lb's using a web based conversion calc.In the FP That i ran above, there is no alternate, but i requested about 12,000Kg's (26400 lbs) to be the Remaining Fuel, which is about what i would plan for for a KLAX EGLL trip including divert to EGKK about 30 Miles down the road.So, based on an 01:00Z Departure (about 10 Mins time), you would need 149,420 Kg's of Gas, or about 428622.73 lb'sNot sure if that responds to your point, i hope it does, but keep firing away....http://manuelsweb.com/kg_lbs.htm is the conversion calc i used BTW...CheersPaul

I guess the issue is, If you use the table with the corrected nautical air miles.... your going to crash into the ground somewhere over Arkansas.... Here's the deal... I've been working on a fuel calculator for the 747 and I am testing it to see how comparable it is to the fuel tables.... It is very close with the exception of these ultra long hauls.... for some reason... something is funny....

[phil747fan 14]

it can be done easily ...charts taken from misc. manuals using 744 GE pax datas.TRIP 6200 nm 12:40 132500 kg fuel tripaltn kclt 225nm 6500 kg 00:40 final reserve 4200 kg 00:30route reserve 4325 kgtxy 900 = 00:20tow 372.5t zfw 225t carb : 148.4t ldw 240tincrease tow 15t = 4950 kg + tif (387.5t tow 137.45t fuel trip) increase tow 10t = 3300 kg + tif (382.5t tow 135.8t fuel trip )decrease tow 10t = 3300 kg - tif (362.5t tow 129.2t fuel trip)given for CI 100 with step climb cruise.altn at LRC and opt level.LRC 12H45 135000 kg for infos.but this is from real ops manuals and there is a slight difference in fuel burn between PMDG 744 and the boeing numbers between 3 and 5% like in a real 747 fleet and some hulls are burning more. hope this help a little even if it s not in pounds.

[Shmiffy 0]

I guess the issue is, If you use the table with the corrected nautical air miles.... your going to crash into the ground somewhere over Arkansas.... Here's the deal... I've been working on a fuel calculator for the 747 and I am testing it to see how comparable it is to the fuel tables.... It is very close with the exception of these ultra long hauls.... for some reason... something is funny....

Here's a fuel ready reckoner that i started working on before i discovered FOC. Thanks to Steve Bell (G-CIVX on the forum here) for the basic methodAll weights are in KG's.You enter your values in the white boxes, the green boxes are autosum's. Once you have those, you need to run your route through Active Sky or whatever WX addon you use, and enter those into the rte data page winds aloft in the FMC, Once you have done that, you can add or remove fuel using the PMDG options box to ensure that your remaining fuel levels are as required.It's basic, but it served me well before i invested the money in FOC.CheersPaul>>>>>>>>>>>>>>>>>>>Note: I had to change the file extension to .TXT = CHANGE IT BACK TO .ZIP WHEN YOU HAVE DOWNLOADED!!!!!!!!!!!!!! <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<I AM NOT SUPPORTING THIS - IT WAS FOR PERSONAL USE - USE IT OR DONT USE IT, Your Choice....

[falk781 0]

So based on this, I calculate your fuel to be 148,425 KG or 326,535 lbs.? That's 24,656 lbs more than the cruise and fuel planning guide says I should have which is 25,000 lbs short at touchdown as per the FMC calculations???This doesn't make sense to me.... Is it possible that the fuel tables supplied with the 744 are a bit light for long haul? Do you think I should factor in an additional 5% for long haul flights? 5% of fuel added onto the tabled calculation would have brought it up another 16,000 lbs of fuel, but appears to still be short by 35,000 lbs.

[phil747fan 14]

So based on this, I calculate your fuel to be 148,425 KG or 326,535 lbs.? That's 24,656 lbs more than the cruise and fuel planning guide says I should have which is 25,000 lbs short at touchdown as per the FMC calculations???This doesn't make sense to me.... Is it possible that the fuel tables supplied with the 744 are a bit light for long haul? Do you think I should factor in an additional 5% for long haul flights? 5% of fuel added onto the tabled calculation would have brought it up another 16,000 lbs of fuel, but appears to still be short by 35,000 lbs.

Scott,i ve used real life numbers and there is a conflict between those and flying the pmdg. dont know why but there is certainly a problem with FS inside engine. when i created profiles for Foc 2003 i inout the datas inside and gave me back same results as the real planner software were giving at the office. so i know this is not on the perfs parts.but there is too a problem as if you re using the fms for prediction this is still a prediction and you need to feed winds on perfs side to get the better.- i dont know about the guide you re refering is it PMDG one ? so you re using the quick fuel planning chapter 2-7 ? if so i didnt find your number .... let s say we have 6200 nam fl370 this is between 6000 and 6400 so you need to interpolate.flight time 12h53 121.5t for 216t at ldw weight. need again calculation ... 24t more. so ((5.3x454)x12.53h) means 31235 kg to add = 152.7t should the fuel you need for your flight using pmdg datas of course you need to add contingency and reserve. 15.1t = 167.8t total fuel needing. but mach.86 is not the best fuel efficient in todays ops.an old paper made by Marc Brodbeck in 1998 (PS1 days) make this numbers : 135.4t trip fuel 12h52 flight time 4200 kg final reserve 800 kg altn 6.25t route 4.3t so a total : 150.95t very close to my numbers .... i can add more example with another carrier numbers but it wont help you more. as the numbers are not the same from real ops and pmdg ( tweakings made somewhere ...) of course more than my own books ... but take the more you want for now virtual fuel is not taxed ...have a good flight.phil