I’ve a question on my end and I need clarification with the power setting of the A333-300 (and the neo version as well):
Simbrief often set flightlevels that seem to high for the A333 engines, even when I do stepclimb.
I learned, that N1 shouldn’t be above 90% in level flight. I can’t stick to this value flying the plane above 38.000ft. Not even to think about FL400.
Is the plane just underpowered in game?
On FR24 this plane easy get beyond the 380 FL mark.
Any ideas or answers anyone?
Thanks
The service ceiling for the A330-200 or -300 is 41,000 feet so it should be slower at 38,000 feet with max payload. You do realize that flightplans are calculated with wait in mind so you would need a lighter load to be flying at normal cruise speeds at 39,000 feet. So yes the A330 can climb to 38,000 feet easily but only if it is light otherwise it normally sticks to 35,000 feet and below. And no the A333 is not underpowered in IF you are just putting to much load on it to properly climb to 38,000 feet. And unfortunately simbrief does not take weight into account
I respectfully disagree, I think that even though you have to be underweight to get to those altitudes, the A330 as well as the A350 have less engine power. I have to climb at 1000 FPM to get to FL 350 whereas the 737 as well as the 777 engine power is over powered.
Wrong. IRL A330s on medium/long-haul routes can climb relatively high early on and be fine.
Yes, it is. We run anywhere from 4-15% higher in N1 than it should at any given phase in climb or at level cruise. The heavier and higher you are, the bigger the difference is. Here’s some reference data: A non-IF A330 at 219.1k kg, can climb to FL370 with a derated climb N1 of 90.1%. Cruising at FL370, M 0.813 requires approximately 83.5-84.4% N1 and about 6000kg/hr of fuel flow. We are by far and large far away from that figure. The IF A330, under the same conditions, cruises at about 97% N1, but it has a matching fuel flow. The issue plagues both the A333 and A339.
Again, wrong. I created two FPLs, both on an A330 flying AMS-JFK. On one, with 300 pax loaded and no additional cargo, it has an initial of FL340 before ending at FL380. On another, with 0 pax and no additional cargo, the initial altitude was FL400 for the whole route.
This is an issue I’ve been aware of for the longest time, and it’s an issue that other folks are aware of too. Those of us who are the most active surrounding flight physics have the relevant A330 FCOMs, but we are lacking IRL data and feedback to push harder for change. And the A330 pilots I know aren’t interested in helping out, so we’re in a bit of a dead end here.
Thanks for your input, but if you’re going to contest the OP’s claims, you need supporting data and to be correct in what you say.
I have to be extremely careful taking off in a fully loaded A333 and A339. Rotated a bit too early once, and almost stalled.
Despite being underpowered, it’s still one of the nicest planes to fly (and land) on IF. In addition, it’s an aesthetically pleasing plane to look at, if I may say so
The A332 can climb higher than the A333 the A333 typically always flies at around 35,000 while the A332 flies at around 37,000 with the same amount of load due to being smaller
Also I use Simbrief to and for an A350 flight from Chicago to Barcelona Initially planned 242 passengers and it said 38,000 feet and then I changed it to just 355 over 100 more and it actually said 39,000 feet (same fuel and cargo for both). So it doesn’t seem to to take weight configuration it is rather just random
Except we’re not talking about the -200 at all in this situation, so I don’t know why you keep bringing it up. There’s also a lot more that goes into cruise altitude calculations than just “one plane small, one plane big.”
I didn’t know we shifted topics to the A350 now.
You’re welcome to tell a SimBrief Developer he doesn’t know what he’s talking about then.
If you’ve got no concrete data and nothing productive to contribute towards this thread, then there’s no point reasserting your opinion just for the sake of doing so. The FCOMs and what IRL data I do have clearly states our A333/A339 are both woefully underpowered for what they are. If that’s against your belief, bring it up to Airbus directly.
Thanks all for your answers, so long story short: the plane in IF does not behave like the plane irl. So I did right to stay at lower altitudes other than the irl plane normally reach!?
For what it’s worth, I’m going to clarify this. The A330 (both -300 and -900) climbing like an absolute pig on a hot day is absolutely expected. It’s like this in real life - just a colossal dog of a climber. The issue lies here:
For an A333, at the N1 we’re using in IF to achieve climb performance we’d get IRL, we’re about 5-15% too high on our N1 figures. For example, to climb at 1500fpm, 310kts, 218.6K kg, FL230 and climbing, TAT -14C, SAT -40C, the IF plane needed about 88-91% N1. The IRL plane under the exact same conditions required only 78-80% N1.
Similarly, in the IF A333, to cruise at FL330, M0.808, 218.6K kg, FL330, TAT -27C, SAT -55C, we needed about 90-91% N1. IRL under the exact same conditions, the plane only needed 77% N1.
The plane is supposed to be a dog, but the IF one is too big of a dog.
Until we can get an updated flight model, stay 4-6K ft below what the IRL plane is capable of doing at any given weight/temp.
Are you using a custom airframe? If so, go into the custom airframe section and scroll down until you see “Cruise Level offset”. There, you can change the flight altitudes by taking off thousand/hundreds of feet if you think the a333 is flying too high of an altitude. In my opinion, I don’t really see much of a problem with Simbrief’s calculations. I highly suggest you use a custom airframe so that you reduce any discrepancies you feel there are between SimBrief and IF.
Sure thing . The cruise offset adjust your cruising altitudes by the 100s or 1000s. For the most part, the 100s is pretty useless unless you’re flying VFR maybe. It can change the 1000s if the selected offset is closer when rounded to the nearest 1000. With the cruise level offset, you can see n1 go up (setting a plus offset) or go down (setting a minus offset). The fuel factor takes into consideration how much more/less fuel the plane is burning by %. So if you’re plane burned 30% less, you would use M(minus) 30. Though I will say, it’s not really consistent for a set flight. Most planes in IF are actually more overpowered fuel efficient than what an actual airplane burns and I think the a330 may be one of those planes that is more fuel efficient. That’s why we use the fuel factor. If you do a short-medium haul with the fuel factor, you may find your burn on par or closer with SimBrief. If you do a long-ultra long haul, you may find you’re burning more than what SimBrief calculates. It’s kind of funny because SimBrief calculates more efficiency already with the base adjustments for the already efficient IF aircraft and the IF aircraft has a hard time performing to the adjustments. I think this has something to do with IF data and what I’ve heard up above is just adding to my confirmation bias. Anyways back to you, that’s basically what cruise level offset and fuel factor do.
This fits what my old calculator for the A333 in IF gives. For 219k kg on a ISA temp, it gives FL 350 as initial altitude instead of FL370, so as to respect the RL max N1.
. The cruise offset adjust your cruising altitudes by the 100s or 1000s. For the most part, the 100s is pretty useless unless you’re flying VFR maybe. It can change the 1000s if the selected offset is closer when rounded to the nearest 1000. With the cruise level offset, you can see n1 go up (setting a plus offset) or go down (setting a minus offset). The fuel factor takes into consideration how much more/less fuel the plane is burning by %. So if you’re plane burned 30% less, you would use M(minus) 30. Though I will say, it’s not really consistent for a set flight. Most planes in IF are actually more overpowered fuel efficient than what an actual airplane burns and I think the a330 may be one of those planes that is more fuel efficient. That’s why we use the fuel factor. If you do a short-medium haul with the fuel factor, you may find your burn on par or closer with SimBrief. If you do a long-ultra long haul, you may find you’re burning more than what SimBrief calculates. It’s kind of funny because SimBrief calculates more efficiency already with the base adjustments for the already efficient IF aircraft and the IF aircraft has a hard time performing to the adjustments. I think this has something to do with IF data and what I’ve heard up above is just adding to my confirmation bias. Anyways back to you, that’s basically what cruise level offset and fuel factor do.
