High throttle on the A350

So I was doing a flight from London to Manila with the A350 however when I reached my initial cruise altitude (FL350), my throttle was like at 83% (not N1). I took 295 passengers, 14:30 hours of fuel and 6 tons of cargo. The real flight also cruised at FL350. However on most flights they cruise initially at FL370 but it is impossible to do this in IF or the throttle would simply go crazy. Why is this happening even though I’m taking a realistic amount of passengers and cargo? The A350 is quite new so I would expect it to perform as IRL, however it seems it doesn’t.

For some reason the A350 is a lot more efficient below FL350, so i think you are correct here. The fuel flow at certain altitudes is kind of messed up.

I would just stay at FL310 or FL330, or get less cargo and pax.

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Why was this accepted when the aircraft was added back in December 2019? I am really shocked because I would expect an accurate fuel burn on reworked/new aircraft.

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Hello there!

I fly the A350 at realistic high altitudes, a high powered cruise is natural with the A350. The other day I had a flight that went straight up to 43,000ft for 3½ hours. No issues.

Using the fuel fpltoif.com/simbrief gives you, no matter the realistic altitude you should have plenty left on landing, even if it doesn’t look like it initially (because the aircraft will get lighter as more fuel is used). All I can suggest is to watch your climb when on a heavy-ish weight.

So basically it’s “normal” if my throttle reaches like 85% at initial cruise? I didn’t think so because this doesn’t happen on planes such as the 777.

No aircraft specifics are the same. The 777 generally has much more powerful engines, although the A350 have lower powered, more economical engines. It uses a higher engine power, but less fuel.

@Ecoops123 I am not sure, but as aircraft get lighter, they are supposed to be more efficient at higher altitudes.

However, I don’t think this happens in the A350, do you get what I mean?

Cruising at power of about 85% is completely normal early on, even at higher altitudes. This varies from aircraft to aircraft, with the 777 needing less power due to its much more powerful engines, though at the cost of fuel efficiency.

It is possible that you actually had a higher payload than the real flight did. What with the pandemic going on at the moment, a lot of flights are running with less traffic load than usual. In other words, you might have had too many people on board. This would’ve required more fuel and could’ve limited your initial flight level as a result.

I’m not sure why people are banging on about the 777 having more powerful engines on this thread… I didn’t personally interpret the original post as a question of comparison between the A350 and B777s but as a query into why the A350 potentially performs unusually.

From a real world perspective here is an fantastic video of real world ops onboard an A350.
(1:19:00) - If you look closely on the onboard displays you can see the A350 cruises at around 70-80 procent N1. So what you experienced was completely normal :)


While the original post did not have any mention of the 777, an additional post further down the thread by the original poster did make a comparison between the A350 and the 777 and their performance at initial cruise, hence why people started mentioning it :)

There is a bug in the A350 fuel data actually: for some reason at a specific N1, fuel burn decreases with increasing N1 above like FL350.
Yeah A350 fuel burn is really off. Not sure why, but lierally almost every aircraft in IF burn less fuel IRL.

The OP said the plane is using 83% throttle, which is over 90% N1! Way more than it should be.

No it’s not. That’s 87% on the A350. A350 maxes at 101%N1

Still… more than usual.

It’s not? A330 uses over 85 N1 at most efficient altitude as well (in IF that is)