Fabo 41 Posted December 28, 2012 Share Posted December 28, 2012 Hello, sorry, I made a little mistake. 0 trim is not at 27% but about 28,5%. Anyway please take a look at this graphic. I have included several points (in green) at the "Ideal Trim Line" for this specific airline. Note the wording from their manual: In the interest of fuel economy the load in the compartments shall, whenever possible, be distributed in such a way that the LIZFW is aft of this line (Emphasis mine) Any fuel load over 5 tonnes will move the LITOW point a bit aft. I have taken liberty of entering a fuel load of 8 tonnes to ZFW of 61t and projecting the TOW index/CG in red color. You will notice following the line this means almost 31% TOWCG and a trim of about -0.5 stab trim (that is, 0.5DN) and the airline asks to load the load even more aft if practical. Link to comment Share on other sites More sharing options...
Kostap 19 Posted December 28, 2012 Share Posted December 28, 2012 Hi, thank you all for this thread! The first days were filled with getting everything to work and getting used to Sparky. Now I started looking at the performance and weights, CG etc wondering if I could use Topcat with it. And presto - here is a thread and a profile (great stuff - thanks). So, I did a few takeoffs from rwy 07 in EDDS with different performance settings and compared it with Topcat. It really comes close to what Topcat calculates. Here is an example for a takeoff and its values: EDDS rwy 07 (3345m) no winds, +13 deg 1013 QNH dry weather (standard weather in FSX) AXE A320 CFM Topcat with that new profile calculates: 120 pax 2067 kgs baggage: ZFW 53390 kgs --> 29.5% MAC, fuel 7.4t trim 1/DN1.2 FLEX 63: V1/R 147 V2 148 83.3% N1 842m margin I entered the relevant values in PERF and INIT B (that flex temp changes to 67 again (I hope a SP/HF will fix this) but the FLX N1 displayed was 83.4% which is really close to the Topcat value. Trim was in fact down and not up. In reality it is more down than up but depends on the situation. On takeoff I got to V1 at about the middle of the runway and was up and away before reaching the 842m margin. So far I cannot complain. If some of you get close to the rwy threshold you may want to check your weight, fuel and FLX % displayed and when pushing the levers to FLX MCT have an eye on N1. I will make notes for more T/Os when flying them and can post the information here if you are interested. Kosta Link to comment Share on other sites More sharing options...
Kostap 19 Posted December 28, 2012 Share Posted December 28, 2012 a quick addendum: the trip fuel calculation of Topcat with this profile is too low. EDDS-EDDP was calculated with 2060 kg and AXE tool calculated 2500 kg - it was 2550 kg. I would therefore take the AXE tools trip fuel and overwrite the trip fuel value in Topcat with it. Kosta Link to comment Share on other sites More sharing options...
Max Reverse 344 Posted December 28, 2012 Share Posted December 28, 2012 Hi Kosta, thanks for your information. I am wondering about the 29,5% MAC and the 1,2 Trim down. I just checked a airbus trim calculation sheet, and this could not be correct. Your ZFW is not to heavy for a down trim, accept you put all your stuff and cargo in the aft. compartement of the Bus Link to comment Share on other sites More sharing options...
Jarkko 39 Posted December 28, 2012 Share Posted December 28, 2012 the trip fuel calculation of Topcat with this profile is too low. Hello! You are correct. Topcat only provides a rough estimate (great circle distance X constant value, lets say 1.12). Topcat doesn't know the route you will be flying, or the winds aloft and so on. For best result, you should do fuel planning outside Topcat. Hope this helps! Link to comment Share on other sites More sharing options...
Kostap 19 Posted December 28, 2012 Share Posted December 28, 2012 Hi Kosta, thanks for your information. I am wondering about the 29,5% MAC and the 1,2 Trim down. I just checked a airbus trim calculation sheet, and this could not be correct. Your ZFW is not to heavy for a down trim, accept you put all your stuff and cargo in the aft. compartement of the Bus I know but that is what Topcat calculates and it is flyable. My guess is that the CG values don't really play a big role in the flight dynamics of AXE - it is probably more the weight that counts - but I could be wrong here. Link to comment Share on other sites More sharing options...
Kostap 19 Posted December 28, 2012 Share Posted December 28, 2012 Here is stuff that Topcat calculated for a flight from EDDP to EDDS - I set trip fuel to 2500kg. EDDS 281220Z 22005KT 9999 SCT012 SCT030 BKN045 06/03 Q1029 NOSIG EDDP 281220Z 19008KT CAVOK 02/M04 Q1028 NOSIG EDSB 281220Z 20009KT 9999 BKN043 07/04 Q1029 =============================== L O A D S H E E T ISSUED BY APPROVED DATE TIME 28 DEC 2012 1300 ALL WEIGHTS IN KILOGRAMS ......... .......... LOAD IN COMPARTMENTS 2080 1/891 3/1189 PASSENGER/CABIN BAG 10080 AD/120 C/0 I/0 TTL 120+0 TOTAL PAYLOAD 12160 DRY OPERATING WEIGHT 41243 ZERO FUEL WEIGHT ACTUAL 53403 MAX 61000 ---> 53.4 t TAKE OFF FUEL 7285 ---> not by the time I had travelled to 25R..... 6830kg TAKE OFF WEIGHT ACTUAL 60688 MAX 77000 TRIP FUEL 2500 ---> 2446kg AXE planner calculated this - got ATC shortcut which saved fuel LANDING WEIGHT ACTUAL 58138 MAX 64500 L ---> 58.0t close enough .. CAPTAINS INFORMATION/NOTES STD WEIGHTS USED ADULT/84 CHILD/35 INFANT/0 BLOCK FUEL/ 7400 ( 9164 LITER) LANDG FUEL/ 4735 ( 5864 LITER) ----> [i]4745 kg left[/i] TAXI TIME 10 MIN CREATED WITH TOPCAT 2.71 (30JAN11) AIRCRAFT FILE VERSION 1.16 (10JAN10) END LOADSHEET GWI7L EDDP-EDDS =========================== TAKE-OFF EDDP/LEJ RWY 26L TORA 3600M AXE320 AIRBUS 320-214 CFM56-5B4 LEIPZIG TEMP +6C QNH 1028 WIND 190/08 (02KT HW) ------------------ CONDITIONS ------------------- ** CONF 1+F ** NORM T/O ** DRY ** ** AIR COND ON ** ANTI ICE ENGINE ** ASSUMED TAKE-OFF WEIGHT 60688 KG ------------------ FULL THRUST ------------------- +6C 80000 FIELD 126-139 139 143 1875M 87.9% ---------------- REDUCED THRUST ----------------- -----> +63C 65618 FIELD 146-147 147 148 1278M 80.1% --> we were away at 2000m with 1600m to spare N1 at 80.2% +64C 65125 FIELD 147 147 149 1208M 80.0% +65C 64632 FIELD 148 148 149 1118M 79.8% +66C 63932 FIELD 149 149 150 989M 79.7% //+67C 63232 FIELD 150 150 150 840M 79.6% *************************************************** DO NOT EXCEED MAX STRUCT TAKE-OFF WGHT OF 77000 KG *************************************************** All in all close enough - I start to like the bird more and more OK, it might not all be strictly realistic but you can perform planning and end up with very close results - that is not too bad... Kosta Link to comment Share on other sites More sharing options...
Fabo 41 Posted December 28, 2012 Share Posted December 28, 2012 Hello, I have to second Jarkko - TOPCAT is not a planner. All it gives is a very broad estimate meant to approximate landing weight. In 737s and MDs, I will almost always use less fuel. I can not comment on A320 yet. To get best results, calculate fuel in a proper fuelplanning software and input all values (total, taxi, trip) by hand. Also a small point about "runway to spare", I see some people compare this value with actual runway left after liftoff point, note that this is incorrect. Runway remaining as indicated by TOPCAT is meant to see the margin for rejected takeoff. This can be for ex. useful for a quick guess whether you can accept a shorter runway or an intersection departure. Link to comment Share on other sites More sharing options...
Swen 20 Posted December 28, 2012 Share Posted December 28, 2012 Kosta, the calculation is not wrong. TopCat calc the needed fuel for a flight without safteys. So add saftey and all other things to calc fuel, maybe 2,5t, then you get good data to work with it. Link to comment Share on other sites More sharing options...
Kostap 19 Posted December 28, 2012 Share Posted December 28, 2012 Kosta, the calculation is not wrong. TopCat calc the needed fuel for a flight without safteys. So add saftey and all other things to calc fuel, maybe 2,5t, then you get good data to work with it. oh I did not say it is wrong - as you point out it is a very rough value based on a distance and does not take other factors into account. The AXE tool seems to be optimized on the experience with AXE and its fuel consumption - so I can take the trip fuel from there and let Topcat calculate the rest. AXE tool also adds 2t for contingencies and you will end up with 7+t of block fuel when using it. Which is fine.... Let's not forget that this can only be a rough approximation of real life operations and many are not really interested in that level of detail Fabo, yes there is a difference - but I simply wanted to point out that my takeoffs do not get me close to the runway end like some people. So if you get things calculated and set up properly t/o is no problem. Kosta Link to comment Share on other sites More sharing options...
kidcraig 9 Posted December 30, 2012 Share Posted December 30, 2012 I'll try out the config file! Link to comment Share on other sites More sharing options...
kidcraig 9 Posted December 30, 2012 Share Posted December 30, 2012 With this data: ------------------------------------------ --- CURRENT MEL ITEMS (05:45Z 30.DEC) --- NONE. -------------------------------------------------------------------- PLANNING SUMMARY CI008 FL 370 TDV P10 G/C 919 EET 0224 ---------------- TRP 350 COMP M02 DIS 936 BURN 6.2 -------------------------------------------------------------------- FLIGHT PLAN ROUTE ----------------- DEP MCO RWY 36R KMCO N0450F370 MCOY9 SAV J51 CAE PSK J53 EWC DKK LINNG3 CYYZ ARR YYZ RWY 33R -------------------------------------------------------------------- CLEARANCES ---------- -------------------------------------------------------------------- ALTERNATE INFORMATION --------------------- ALTN CYXU/YXU FL100 DIS 0077 EET 0022 BURN 1.1 CYYZ DCT CYXU -------------------------------------------------------------------- FUEL INFORMATION ---------------- PLANNED FUEL STAT FUEL SUMMARY --------------------------------- --------------------------- FUEL ARPT FUEL TIME STAT FUEL TIME --------------------------------- --------------------------- TAXI MCO 0.2 0008 NO STAT BURN YYZ 6.2 0224 CONT 0.8 0019 ALTN YXU 1.1 0022 FINAL RESERVE 1.1 0030 ETOPS 0.0 0000 WXX 0.0 0000 --------------------------------- BLOCK FUEL MCO 9.4 --------------------------------- EST FOD YYZ 3.0 0111 -------------------------------------------------------------------- FLT RELEASE ----------- DISPATCHER BROOKS RODERICK, . CAPTAIN .............. F/O ............... F/O ............... R/P ............... ADC ............... -------------------------------------------------------------------- TIMES ----- ESTIMATED SKED ACTUAL OUT 1920Z/1420L 1920Z/1420L ......Z OFF 1928Z/1428L 1928Z/1428L ......Z ON 2152Z/1652L 2203Z/1703L ......Z IN 2158Z/1658L 2209Z/1709L ......Z BLOCK TIME 0238 0249 ...... -------------------------------------------------------------------- WEIGHTS FUEL ON BOARD ------- ------------- EST MAX ACTUAL ACTUAL AFPAC REL 1 ...... UPLIFT ...... PAX 107 ...... L/USG A/B ...... ZFW 55.1 61.0 ...... DEP ...... FUEL 9.4 18.6 ...... ARR ...... TOW 64.3 70.7L ...... BURN ...... MACGTOW ...... STAB TRIM ...... MACEZFW ...... LDG WT 58.1 64.5 ...... Topcat produced: L O A D S H E E T ISSUED BY APPROVED DATE TIME 30 DEC 2012 0643 ALL WEIGHTS IN KILOGRAMS ......... .......... C. GEAR C. GEAR REMARKS/ AIRAC1202 FROM/TO FLIGHT A/C REG A/C TYPE CONFIG KMCO/CYYZ ACA47 AERO A320 A320-214/CFM56-5B4 C16 Y134 WEIGHT DISTRIBUTION LOAD IN COMPARTMENTS 4923 1/2110 3/2813 PASSENGER/CABIN BAG 8988 AD/107 C/0 I/0 TTL 107+0 TOTAL PAYLOAD 13911 LAST MINUTE CHANGES DRY OPERATING WEIGHT 41243 DEST SPEC CL/CPT +/- WEIGHT ZERO FUEL WEIGHT ACTUAL 55154 MAX 61000 TAKE OFF FUEL 9285 TAKE OFF WEIGHT ACTUAL 64439 MAX 77000 TRIP FUEL 5520 LANDING WEIGHT ACTUAL 58919 MAX 64500 L TAXI OUT FUEL 115 UNDERLOAD BEFORE L.M.C. 5581 LIMITED BY LDW LMC TOTAL + / - BALANCING/TRIM CONDITIONS MACZFW 29.83% MACTOW 34.88% STAB TRIM: 1.4 DN MACLDW 32.04% MAC LIMITS ZFW FWD 16.69% AFT 42.00% TOW FWD 17.00% AFT 42.00% LDW FWD 16.84% AFT 43.00% TRIM BY CABIN AREA A11.B96 CAPTAINS INFORMATION/NOTES STD WEIGHTS USED ADULT/84 CHILD/35 INFANT/0 BAGGAGE/15 BLOCK FUEL/ 9400 ( 3075 GALLONS) LANDG FUEL/ 3765 ( 1232 GALLONS) TAXI TIME 10 MIN SELCAL/CG-BP Takeoff Data: TAKE-OFF KMCO/MCO RWY 36R TORA 12005FT AERO A320 AIRBUS 320-214 CFM56-5B4 ORLANDO INTL TEMP +11C QNH 1021 WIND 310/11 (06KT HW) ------------------ CONDITIONS ------------------- ** CONF 1+F ** NORM T/O ** DRY ** ** AIR COND ON ** ANTI ICE OFF ** ASSUMED TAKE-OFF WEIGHT 64439 KG ------------------ FULL THRUST ------------------- +11C 80000 FIELD 128-142 142 146 6411FT 88.4% ---------------- REDUCED THRUST ----------------- +64C 67388 FIELD 149 149 150 3346FT 81.2% +65C 66947 FIELD 150 150 151 2834FT 81.1% +66C 66247 FIELD 151 151 152 2201FT 80.9% +67C 65547 FIELD 152 152 152 1290FT 80.8% //+68C 65069 FIELD 151 151 152 630FT 80.7% *************************************************** DO NOT EXCEED MAX STRUCT TAKE-OFF WGHT OF 77000 KG *************************************************** ------------------ ENGINE OUT ------------------- RT TO 'PRESK' [16.2 DME R 140 'ORL' 112.2] (140 INBD,RT) ---------------------- END ----------------------- I lifted off with about 1500ft or less of runway using +67 as FLEX. I'd say that's pretty close! Link to comment Share on other sites More sharing options...
Fabo 41 Posted December 30, 2012 Share Posted December 30, 2012 Way too close. Then again, maybe you did not fully use correct procedure Link to comment Share on other sites More sharing options...
CPT RENNI 2 Posted December 30, 2012 Share Posted December 30, 2012 Hello, I started this post as an aircraft dispatcher : http://forum.aerosoft.com/index.php?/topic/61897-airbus-weight-and-ballance-calculation/#entry438568 Link to comment Share on other sites More sharing options...
galaio 16 Posted January 4, 2013 Share Posted January 4, 2013 Hello, The CG returned by TOPCAT, using the profile sent in this thread is accurate? I'm getting more or less values between 29 and 30 and a trim about 1 to 1.4 DN. Are you using this trim in your flights? Regards, Galaio Link to comment Share on other sites More sharing options...
G-BOVY 10 Posted January 4, 2013 Share Posted January 4, 2013 Hi guys, here you go with a partial Aerosoft Airbus X Extended profile. It can load people and stuff, and it will compute CoG and takeoff trim. it CAN NOT load FUEL, I repeat it CAN NOT load FUEL. You HAVE to do that by HAND. The CoG values are correct however. note: Ability to load fuel is tied to support of Christian Grill of TOPCAT. At this point, I am not optimistic enough to believe he would grant any in any realistic timeframe. Hi apologies, What do I need to do with this profile to utilise it in TOPCAT? Thanks Link to comment Share on other sites More sharing options...
galaio 16 Posted January 4, 2013 Share Posted January 4, 2013 Just Hi apologies, What do I need to do with this profile to utilise it in TOPCAT? Thanks Hello. Just copy the txt somewhere in this thread inside the folder under TOPCAT where the others profiles are. Regards, Galaio Link to comment Share on other sites More sharing options...
G-BOVY 10 Posted January 4, 2013 Share Posted January 4, 2013 Hi Galaio, It's done! Thanks very much, will test it now. Brgds Rob Link to comment Share on other sites More sharing options...
G-BOVY 10 Posted January 4, 2013 Share Posted January 4, 2013 ZFW 60.1 / FOB 9.0 / MACZFW 30.3 / 1.5DN Cheers Link to comment Share on other sites More sharing options...
Fabo 41 Posted January 7, 2013 Share Posted January 7, 2013 Hello, The CG returned by TOPCAT, using the profile sent in this thread is accurate? I'm getting more or less values between 29 and 30 and a trim about 1 to 1.4 DN. Are you using this trim in your flights? Regards, Galaio Hello, TOPCAT uses relatively aft biased loading, which is how "loading for performace" works in the real world. This is normal, as well as nose down trim is (notice marks on trimwheel, green band goes well past 0, for corresponding TOCG) If you are confused by 0.8UP trim value in MCDU, note that ZFWCG nor trim value change with loading (i.e. this is not simulated, at least for now) I use the trim value successfully. Link to comment Share on other sites More sharing options...
G-BOVY 10 Posted January 7, 2013 Share Posted January 7, 2013 Thanks for the heads up, one might have thought these fields were handled given they can be adjusted. Cheers Link to comment Share on other sites More sharing options...
kidcraig 9 Posted January 14, 2013 Share Posted January 14, 2013 TOPCAT values still seem to be spot on with version 1.03/B! Anybody disagree? Lookin' good! Link to comment Share on other sites More sharing options...
kidcraig 9 Posted January 23, 2013 Share Posted January 23, 2013 Can anybody come up with a way to get the A321 to work in TOPCAT? It shouldn't be too hard, should it? Link to comment Share on other sites More sharing options...
Mik75 30 Posted January 23, 2013 Share Posted January 23, 2013 Since I am having problems with getting airborne before the end of any runway, I wonder what I am doing wrong. I use TOPCAT with the Wilco A320 profile and load fuel and payload via the Aerosoft fuel planner. Once in the aircraft, I check the figures and I always see the correct amount of fuel is in the tanks, but the MCDU always shows a much higher ZFW (something around 10, 15 tons more). I change that by hand with the entry of /XX.X, using the figures shown in the Airbus Fuel Planner. Even though that states something like "fuel and payload loaded" it may not have been the case. So, maybe I am always taking off with MTOW? Link to comment Share on other sites More sharing options...
balus 43 Posted January 23, 2013 Share Posted January 23, 2013 Head over to http://www.vbird-va.nl/airbus/tools.htm and get the takeoff performance calculator Link to comment Share on other sites More sharing options...
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