Raphael_Chacon 6 Posted September 9, 2014 Share Posted September 9, 2014 Hello Guys, Sorry, its more of the same, but browsing around i dont find any precise solution for the fuel issue when planning with PFPX and PMDG 777. I always run out of fuel........ I add a percentage more above the PFPX reccomendations, but whats the point of planing then...... I tryed the "FlyPrecisely" templates...... Not working, recommends even lower fuel than original PFPX´s reccomendations for the same flight..... Any recent solution? Thanks in advance... Link to comment Share on other sites More sharing options...
phil747fan 52 Posted September 9, 2014 Share Posted September 9, 2014 good morning, could give us some samples as a flightplan and your notes during the flight? Phil Link to comment Share on other sites More sharing options...
BW901 58 Posted September 9, 2014 Share Posted September 9, 2014 Sorry not quite 777, but I dunno where the "Fly Precisely" info comes from. The data files for the 767-300ER with CF6-80C2B4 powerplants looks identical to the PW4056, and for the 767-300ERW the CF6-80C2B7F, CF6-80C2B5 and PW4056 are all the same. I wonder why we bother spending so much time in the real world deliberating over engine manufacturer and variant if they all have the same performance?? Jon Link to comment Share on other sites More sharing options...
Raphael_Chacon 6 Posted September 10, 2014 Author Share Posted September 10, 2014 Hello, My FP: Thanks in advance.... Link to comment Share on other sites More sharing options...
phil747fan 52 Posted September 10, 2014 Share Posted September 10, 2014 seems on Avsim you gave more details .... flight time, fuel burnt, Cost Index ... please tell us more ... Phil Link to comment Share on other sites More sharing options...
phil747fan 52 Posted September 10, 2014 Share Posted September 10, 2014 well the figures you found with PFPX are into BOCO 777 perfs so something to dig into with your CI, winds and maybe PMDG fuel burn ... did you use acceleration time too ? Link to comment Share on other sites More sharing options...
pcubine 15 Posted September 10, 2014 Share Posted September 10, 2014 LRC is not a CI. You need some number which is usually between 0-99. No winds on this flight? What are you using for weather? You need to determine the fuel bias for the plane. That looks like you maybe used the default figure for bias. On the 777 it is usually between 95-99%.Michael Cubine Link to comment Share on other sites More sharing options...
AALScott 1 Posted September 10, 2014 Share Posted September 10, 2014 do you calculate BIAS whith weather or No Weather Link to comment Share on other sites More sharing options...
phil747fan 52 Posted September 10, 2014 Share Posted September 10, 2014 back to the op. if you generate a LRC fplan you need to input LRC on the FMS otherwise it wont give you the right result. you used BIAS of +4% seems not enough but in the same time maybe you didnt get the same weather system and so encounters worst wind. how long between the planning and the flight? to Michael the CI are implemented up to CI 999 and in the fms it s up to 9999 if my memory serves well. on the bias it s a number above 100% that needs to be implemented as we need more fuel than planned, if we needed less then the bias will be below that number. 100% represents the perfect match condition between the builder perfs and the frame ... Scott : the bias as nothing to do with the weather. it s the fuel needed by the plane compared with the fuel theorically needed from the data fed into the profile ... Link to comment Share on other sites More sharing options...
pcubine 15 Posted September 10, 2014 Share Posted September 10, 2014 to Michael the CI are implemented up to CI 999 and in the fms it s up to 9999 if my memory serves well. on the bias it s a number above 100% that needs to be implemented as we need more fuel than planned, if we needed less then the bias will be below that number. 100% represents the perfect match condition between the builder perfs and the frame ...Fuel costs a lot of money. For climb I use 20 for the 77LR and 40 for the Freighter. I switch to 0 once I have reached the first cruise altitude. I use 98% for a bias.Michael Cubine Link to comment Share on other sites More sharing options...
phil747fan 52 Posted September 11, 2014 Share Posted September 11, 2014 Michael, i hope they re not charging you that much on virtual fuel ... lol the BIAS is a variation based on fuel performance in percentage. i dont think there is a pmdg 777 doing below 100% it s more 104 to 110% so with that bias you re using you may find you short of fuel one day ... wish you a great day. Link to comment Share on other sites More sharing options...
Flight Conex 11 Posted September 16, 2014 Share Posted September 16, 2014 It's the opposite for me, I p,an a flight and I always arrive with 10T more than I want, I use the template provided in the Aerosoft download section for the PMDG 777-300ER and the fuel is always 10T extra on arrivl, I have tried to adjust the template manually but no joy, the B77L worked really well, just the B773 seems to be way out in calculations of PMDG vs PFPX Link to comment Share on other sites More sharing options...
phil747fan 52 Posted September 20, 2014 Share Posted September 20, 2014 Flight Conex, dont understand how you ll find a such difference ... could you post a flightplan for a -300 and your found results? yours truly. Phil Link to comment Share on other sites More sharing options...
Flight Conex 11 Posted September 25, 2014 Share Posted September 25, 2014 Thanks Phil747fan - sorry for late response. please see example. I will be away for a week and will not have chance to experiment in FSX, please bare with me. UAE018/25 SEP/MAN-DXB A/C: A6-ECN [ OFP ] -------------------------------------------------------------------- UAE018 25SEP2014 EGCC-OMDB B77W A6-ECN RELEASE 1515 25SEP14 OFP 1 MANCHESTER-DUBAI INTL WX PROG OBS ASKY ATC C/S UAE018 EGCC/MAN OMDB/DXB CRZ SYS M.83 25SEP2014 A6-ECN 1405/1425 2100/2115 GND DIST BOEING 777-300ER GE90-115BL STA 2115 AIR DIST 3096 CTOT:.... G/C DIST 3057 AVG WIND 255/020 MAXIMUM TOW 351.5 LAW 251.3 ZFW 240.0 AVG W/C P011 ESTIMATED TOW 286.2 LAW 233.6 ZFW 225.0 AVG ISA P08 AVG FF KGS/HR FUEL BIAS 0.0 ALTN OMAA TKOF ALTN ....... FL STEPS EGCC/FL330 PEMUR/FL350 SOGUM/FL370 -------------------------------------------------------------------- DISP RMKS -------------------------------------------------------------------- PLANNED FUEL --------------------------------- FUEL ARPT FUEL TIME --------------------------------- TRIP DXB 52590 0635 CONT 5% EBL 529 0005 ALTN AUH 4881 0019 FINRES 3176 0030 --------------------------------- PLANNED T/OFF FUEL 61176 0729 --------------------------------- OPN --------------------------------- T/OFF FUEL 61176 0729 TAXI MAN 660 0020 --------------------------------- BLOCK FUEL MAN 61836 PIC EXTRA ..... TOTAL FUEL ..... REASON FOR PIC EXTRA ............ -------------------------------------------------------------------- FMC INFO: RESERVES 8057 TRIP+TAXI -------------------------------------------------------------------- -------------------------------------------------------------------- Link to comment Share on other sites More sharing options...
Renato Roberto 0 Posted October 8, 2014 Share Posted October 8, 2014 Guys, Normally, the "Cost Index" used in T7 is 170. In cruise, the speed is next to 0.84! In the Boeing 767-300ER, is next to the 85. Between Mach 0,802 and 0,807, depending on the weights. The "Bias" can be fixed easily. Plan the flight in the normal way. During the cruise (not in the first hour), write down these numbers: - Actual Gross Weight; - Altitude; - Cruise cost index (170 in the T7, 85 in Boeing 767-300ER), we use this data in our airline; - SAT temperature at the moment; (in the FMC, progress page, page 2) - Actual Fuel Flow (total, not only one engine); - Actual TAS (in the Navigation Display); - Actual Ground Speed (also in the navigation display). After that, open the PFPX, go to Aircraft Manager, then Aircraft Database. Select the airplane that you guys are using at the moment, click in EDIT. Then, in the upper part of window, you will see "Evaluate" button. Place the data recorded in the appropriate fields.. Below the window (calculated conditions), you will see the data modified. Click in APPLY, then SAVE. What did you do? You simply informed the system the actual weight, winds, temperatures, and next time you open the PFPX, your calculations will be more accurate. In my case, is: Engine A/Ice = 3% Total Anti Ice = 5%; Climb, cruise and descent bias = 94,5% Drag = 100,4% In all my flighst, the difference between FOD (fuel on destination) and real fuel in the tanks is next to the 500 kilograms in the touchdown. Be sure to note the amount of fuel on board when aligned on the runway. Compare this value with the value informed in the taxi fuel, and also with the minimum value for takeoff. You use this value to compare the values of the flight plan on paper in relation to the flight plan in the FMC. Other thing... ETOPS Data. Each airline has your own rules about how distance, weights and speed are to be used. There is a table for that. In the T7 (-300ER), the data used is: Diversion time = 120 minutes Diversion weight = 320.000kg's Max Diversion Distance = 865nm Diversion time = 180 minutes (ETOPS 180) Diversion weight = 320.000kg's Max Diversion Distance = 1.291nm The speed? 320KIAS / Mach 0.84. We use this data in our airline. ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- Hi, webstereo, Make sure that all you data from aircraft matches the data from PFFX. I assume you are from Brazil (I am too), so the units here are Kilograms, not Pounds (LBS). Fuel and weights in kilograms, temperature in Celsius, runway distance in meters, etc... Make sure that all the weights of the aircraft (you can see in the "weight" menu inside FSX to be precise) matches the weights informed in PFPX. I've found differences between them. The Level D has the most discrepancies, because you have 2 types of basic weight: Long Flight and Short Flight. In the real thing, the basic weight of the aircraft is basically the same, with small differences between classes. When the fleet is standardized, there is practically no difference between aircraft. Look at the T7 as well. There are differences between the empty weight of the aircraft and the empty weight in PFPX. They also have to be the same. If not, correct the PFPX data. Looking to your flight plan, you're using the LRC (Long Range Cruise). Your "normal" cruise will be Mach 0,84, using the Cost Index of 170. Values below 100 are hardly used. Other thing... São Paulo / Congonhas Airport (SBSP) is not used as an alternate airport in any case (is a domestic aiport with less than 1.800 meters of runway). If you are going to São Paulo / Guarulhos Airport (SBGR), the primary alternate airport will be Rio de Janeiro / Galeão (SBGL). The second alternate airport is Belo Horizonte / Confins (SBCF). We use extra fuel if the weather (or traffic) at the destination airport are bad at time of landing (rush hour). If there is no problem, the value is zero. 500 kilos of taxi is a good value for PMDG 777. The contingency fuel is correct (5%), but you can reduce to 3% if you do a redispatch procedure. We always do that. Don't forget the "Hold Fuel". 30 minutes is a good value. Best regards, Renato! Link to comment Share on other sites More sharing options...
FlyPrecisely 124 Posted October 8, 2014 Share Posted October 8, 2014 Guys, Normally, the "Cost Index" used in T7 is 170. In cruise, the speed is next to 0.84!Isn't it a bit high? CI170 speeds are somewhere near the LRC ones. In BAW CI100 is used on their 777, Emirates fly their 777s even with lower CI (usually around 30–40). Link to comment Share on other sites More sharing options...
Skyrock 4 Posted October 8, 2014 Share Posted October 8, 2014 A CI of 85 for the 767 seems well too high as well, as the 767 burns way more fuel at speeds above .79-.80 while not being way faster than at .78 or .79. A CI of 30 seems to be better. Link to comment Share on other sites More sharing options...
Renato Roberto 0 Posted October 9, 2014 Share Posted October 9, 2014 Isn't it a bit high? CI170 speeds are somewhere near the LRC ones. In BAW CI100 is used on their 777, Emirates fly their 777s even with lower CI (usually around 30–40). Yes, you're correct. The flight is planned using this value, but depending on the weather (and especially the price of fuel), the CI may be lower. Then there's the main factor: each airline has its standard. Each one of them fits the CI as needed. An airline does not use the same data as the other. I used a CI of 22 last week, on a short flight. I reproduce below the data (in kilograms): CFP INPUT MESSAGE DATE TIME REF 021014 START OF CFP REF : EWNUT - xxx8026 01 SBGR SCEL *** RECLEARANCE FLIGHT, RECLEAR FIX *** ** EXTRA FUEL DUE TO WEATHER ** *********************************** CAPTAIN OSVALDO - 492488 FLT DISPATCHER ROSANA 105235 / FLT RELEASE TAM 8026 SBGR/GRU TO SCEL/SCL INT SACO/COR ECO CI 22 ELEV 2459 FT 1555 FT 1604 FT WX OBS TIME 0000Z 10/02/14 NAM 1630 AVG W/C M051 AVG/TMP M50 RC EWNUT GC 1413 AVG W/D 272 ROUTE REGN DEG TIME DIST AFU B/O CRZ TOF TOW LGW UNITS ATOF ATOW GRUSCL1 PT-MUD 0.6 3.34 1449 3.0 25.6 ECO 42.7 247.2 221.6 KGS FUEL TIME CORR OWE 170900 PYLD 33600 APLD .. .. .. DEST SCEL 25600 0334 .. .. EZFW 204500 MZFW 237682 AZFW .. .. .. RRSV 10PC 900 0008 .. .. ETOW 247200 MTOW 346544 ATOW .. .. .. DEST-MNVR 0 0000 .. .. ELDW 221600 MLDW 251290 ALDW .. .. .. ALTERNATE 10300 0129 .. .. SAEZ FL 390 708 NM M.82 W/C P059 HOLD 2900 0030 .. .. MFR 39700 0541 .. .. EXTRA 3000 0031 .. .. TOF 42700 .. .. TAXI 600 .. .. FLIGHT TIMES ETD 1120 ATD .... FOB 43300 0612 .. .. ETA 1454 ATA .... FUEL TIME CORR DEST SACO 19400 0239 .. .. ELDW 227800 MLDW 251290 ALDW .. .. .. RRSV 1800 0016 .. .. DEST-MNVR 0 0000 .. .. ALTERNATE 6400 0051 .. .. HOLD 2900 0030 .. .. MFR 30500 0416 .. .. EXTRA 12200 0206 .. .. TOF 42700 .. .. TAXI 600 .. .. FOB 43300 0622 .. .. RECLR ROMUR TO SCEL/SCL AVG W/C M056 NAM 0606 DEST SCEL 7700 0124 .. .. RRSV 900 0008 .. .. DEST-MNVR 0 0000 .. .. ALTERNATE 10300 0129 .. .. HOLD 2900 0030 .. .. MFR 21800 0331 .. .. EXTRA 3000 0031 .. .. FOB 24800 0402 .. .. ATC CLRNC:.. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. SBGR DORMI UL310 ARULA UM400 CBA UA307 DOZ UA306 UMKAL NAVAR5 SCEL FL 360/SOLER 380/DOZ 360 Our cruise speed was Mach 0,826 = very slow for B77W in my opinion! In this route, we have strong headwinds. From SCEL to SBGR, we have strong tailwinds. I don't have the flightplan back to SBGR, but we used CI of 130. The mach number was 0,833. It is not so far from Mach 0,84, right? Other thing... Sometimes, you want to decrease the delay in flight (this situation happens when taking off from JFK, for example). Then you select manually Mach 0.84 and compares the fuel of navigation using the CI compared to fixed speed of 0.84. So we decided to use 0.84 because there is little difference in fuel at the end of the flight. Does not affect safety in flight. Best regards, Renato! Link to comment Share on other sites More sharing options...
FlyPrecisely 124 Posted October 10, 2014 Share Posted October 10, 2014 Yes, you're correct. The flight is planned using this value, but depending on the weather (and especially the price of fuel), the CI may be lower. Then there's the main factor: each airline has its standard. Each one of them fits the CI as needed. An airline does not use the same data as the other. …Other thing... Sometimes, you want to decrease the delay in flight (this situation happens when taking off from JFK, for example). Then you select manually Mach 0.84 and compares the fuel of navigation using the CI compared to fixed speed of 0.84. So we decided to use 0.84 because there is little difference in fuel at the end of the flight. Does not affect safety in flight.Well, the CI mode in PFPX aircraft profiles allows automatic wind Mach corrections in the programme, so do the aircrafts' FMS when you choose the CI. Link to comment Share on other sites More sharing options...
zeke78 1 Posted October 10, 2014 Share Posted October 10, 2014 Hi all, CI170 is a bit high, but some airlines use something close to that, eg Fedex uses a fix CI of around 150. Emirates on their ULR flights uses almost CI10 all the time, on the other flight these days revolves around 25 and 40. 150/170 gives you pretty much LRC as long as you're flying at the recommended altitudes of the FMC. The diff here is, for example, both CI150 and LRC will give you around mach .84 give or take a few decimals if the T7 in question as the decimal installed with the block point version in that scenario.. The diff comes if for example the optimum altitude is showing say, 350 and you're flying at 290 for some weird ATC restriction. Then you're LRC would be probably something like .81/82 (ball park number) but with CI150/170 it would still be .84. Just my 2 cents Rgds Link to comment Share on other sites More sharing options...
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