[ Closed ] XP11 JD330 v.3 r1,r2,r3,r4,r5 (Page 9 of 14)

Me to as well

This is one of the annoying gripe sessions ! What do you mean with fuel flow/ Do you mean fuel flow to engine? (f = [(Tt4 / Tt3) - 1] / [(nb * Q) / (cp * Tt3) - Tt4 / Tt3]), do you mean fuel flow from one tank to another? Or du you want to say fuel burning/h (consumption)?   Generally to say the A330 burns 20% too less fuel is nonsense! Fuel burning depends of X factors like FL, winds, weight, temp, engines type etc. that variate from flight to flight. You have not give us one example  a n d  numbers that we can compare for a serious discussion......

hello there. Since I updated my A330 I've being having a problem. It doesn't fly straight. It flies in zig zag. Does anyone know what's going on? I love this bird and use it all the time with my long haul flights. Attached are pictures of what it's being doing lately.

thank you!

Seriously i am quite surprised. I first didn't want to invest time in having to prove that there is a problem and am seriously wondering why you still didn't notice the big difference in fuel burning beetween reality and that model. I was expecting users here having enough knowledge in aviation like having made observations from real DVD-flights and cockpit preparations etc. to notice this inacuracy. Anyway, here are the exact numbers:

On the left you will find the burning rates according to the original performance table from Lufthansa and on the right the ones measured during a Test-Flight with the Jar 330:

weight 185'000kg, FL390, M 0.80: 2'599 Kg /h    Jar = 2'099 Kg/h (difference: -19%)

weight 180'000kg, FL390, M0.80: 2'507 Kg/h    Jar = 2'054 Kg/h (difference: -18%)

To measure it i disconnected the Autothrottle and adjusted the thrust leveler to the exact point where the speed stayed at Mach 0.8 during at least 10 minutes, so that the FF was constant.

The test-flight i made was LSZH-GMMN. The professional flight planner PFPX - built using real world professional performance datas - calculated 14'852Kg of Tripfuel. But the Jar burned only 12'360 Kg on that trip (-17%) although the winds were quite similar to the ones taken into account by the Flightplanner. On longer trip these difference is a bit bigger since the take off and landings are counted in that number and on short trips the cruising phase is shorter compared to them.

Another thing i noticed is that the take off performance seems to be quite inaccurate as well. I could barelay take off form RWY 28 in LSZH (2500m) with a weight of only 190 tons, flaps 2 and Flex 40. I had to push the throttle to TOGA to lift off 300m before the end of the Runway.

Summary: the perfomance of the Jar 330 is quite inaccurate and i dont understand why nobody noticed that before or why there is no interest fixing that.

Well the Performance table mentioned above does belong to an 330-200 as found in the Infos below that table. But the table is for the -200 equiped with PW4168A engines instead of the RR Trend engines, which could be a reason for the differences. Furthermore you should take in mind that the table is only used in ISA Standard Atmosphere and for a CG of 37%, so if you have flown with real weather and another CG there are more factors which could lead to differences.

I will also do another check flight to see if there are any significant diffences in fuel usage on my side.

Ok so let's invert the question then. Can you please give the source where the actual fuel consumption of the Jar330 applies? I need the real values and a source. If you are doing further tests, what will you compare the results with? To which source? And seriously, the CG and ISA temperatures wont made that much of a difference. They don't even do it in the FF 757, FF320 or IXEG, where the fuel burning rate matches the tables. So it doesn't make sense arguing which such details.
We had the same problem with the FF 777 who suddenly had wrong performance when used in XP 11 compared to XP 10 and that has been discussed in the org forum many times. And the same seems to happen now with the Jar330. The Fuel Flow was correct in XP 10 and now its burns 20% less on long hauls. So can you explain me why this happened? Is it because of CG? Is it because of the ISA temperature? Where these values all wrong in XP 10, although how wonder they matched all comparaisons with real values?  Its's so obvious there is a problem and i can't understand why some users don't want to accept it. There is no argument or prove at all that shows the actual values being right. Its the opposite in fact: every comparaisons shows they are not. I really would appreciate an official statment form a developper here.

Yesterday I made a flight from SBBR to SBDN (Brazilia) using also data from simBrief.com. Prediction of fuel consumption for flight (exclusive 15 min push and taxi) 7274kg. At the end of flight (40kt tailwind over all flight route)  the difference to JAR A320 was 7%. I guess that flying under other wind conditions the difference could be less.....

@Homer and Ilankrt: i doubt Simbrief is an accurate base. Or do you seriously think its more accurate than PFPX? Without comparaisons with real tables like i've done its useless. And below 3 hours of flight its also quite useless since the main difference appears during cruise. And on short flights you wont remark that difference because 5%-7% could be also because of winds differencies or differences in take off / approach performances. So its not an accurate way to compare.

Anyway: it was about the A330 and not the A320 (to Ilankrt)

So as long as nobody can show that the values are correct based on REAL tables like i've done, do we have a chance that these wrong fuel burning values will be fixed in future? But as it seems there are no developpers reading here?

v3r4
1. ZBAA RWY36R Go-Around route - why the aircraft draws such awkward turn like that?
2. Missing runway symbol ("="symbol)
3. Alt constraints below FL100 shouldn't show "FL" - 3940ft shouldn't be FL3940 right?
4. From cold and dark, why the RAT is deployed?
5. After takeoff, the ND went out however the zoom function of the ND is still available.
6. Forget one thing during engine start - before clicking the ENG1, the EPR indication in the EWD rotates violently - I just used keyboard for my engine input, no hardware throttle control.
7. F-PLN in selected mode - the curved f-pln is still solid, but the rest of the straight lines are dashed.
I am using the latest stable version of XP11.
Please fix them in the next version.

I just updated to Version 3.0. The handling is much better but I noticed that the aircraft ascends and then descends a few feet during the cruse and does not hold at assigned FL. Also the auto throttle is constantly adding and reducing power.

I followed all the instructions (I started using JAR when their A320 was in version 1.2 so you don't need to ask me to read about the FAQ - we wrote the operation manual in simplified chinese dated back in 2014 in Chinese x-plane portal).
My point 7 - yeah in the selected mode all the f-pln should be in dashed however only the straight lines are dashed - I am asking why the curves are not. (And from that time I have pointed out there was no dashed line in selected mode in 2014 but no one replied in this forum.)
My point 1: simply because the drawing algorithm for the f-plan and ga route is not as clever as other aircraft. Just admit the fact that it has shortcomings and will improve.
For starting the engine sequence - first engine? it doesn't matter which engine starts first - both engines indication rotates. Throttle is always in idle position. Usually we start our right hand engine first as the jetways are usually in our left side - starting engines from the right side will minimize the risk of potential damage to jetways if the engine on the right side fail/or catch fire.
ND went out - come on I didn't touch anything.
RAT - again I didn't touch anything.
On runway without engine started - simple. I respawn on the runway just to test the aircraft. Are there any problems?
Please, focus on my findings.
And thanks for the map however it's rather useless to me. As the RL airline guy, I have the latest and full set of charts for ZBAA published by CAAC and my company operates about 20 flights a day to ZBAA.

Anyway thank you for your reply.