Is the A340-300 underpowered?

I’ve seen many posts about the A340-300 being very sluggish and less efficient than the newer A340s. My question is, why is this? I’ve often seen them as low as at FL280 on the beginning of some long haul flights. Are the engines at fault?

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They have the same engines as the A320-family (CFM-56) but four of them instead of two, and almost 200 tonnes higher MTOW…

I’m far from a professional when it comes to this, but slightly underpowered…


No, although more modern variants as obviously more efficient and better equipped. The reason for such a low altitude in the early stages of flight is purely weight, as the aircraft wouldn’t fly efficiently at a height much higher than that.

Yes, almost! They have 151 kn so on a whole side 302 kn that is the same as the A 330 only with a motor … I do not think that is so sluggish on the contrary he has been the first long-haul aircraft from Airbus … Istanbul-Los Angeles Nonstop

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I wouldnt say its underpowered, since it gets off the ground and flies without any problems. It just doesnt have a particularly good power to weight ratio.


Yeah, that’s a more appropriate description


Today I just learnt something new.

I always thought the A343 and A332 engines were the same.

I checked out what wiki had to say and your statement is correct.

" As of July 2016, 30,000 engines have been built: 9,860 CFM56-5 engines for the Airbus A320ceo and A340-200/300 and more than 17,300 CFM56-3/-7B engines for the Boeing 737 Classic and 737NG"

Fascinating to say the least.

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It’s got the same engines as the KC135, surely they aren’t that underpowered considering their use?

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They are also not quite so efficient … 4 engines → more maintenance, more kerosene, more inefficient … But still one of my favorite aircraft …
In addition, this is the predecessor for the A 330 only then you have implemented the 2 in 1 engine … with the same thrust …
So there is not that much difference …
In the meantime it was normal for Airbus to have 4 engines instead of 2 … like Boeing they were more efficient with B 767

I think being underpowered is more of a meme than anything as the engines are also referred to hairdryers because they seem so small on such a large aircraft.


You are correct. They are hairdryers indeed. They look too small in terms of size proportion to the aircraft.


Well I will give you a list (This is all my opinion and should not be a start to a long discussion for me)

  1. The A340 family is notorious for near tailstrikes to total tailstrikes, especially the -300.
  1. It isn’t as fuel efficient as most competitors.

  2. It seems like it has hairdryers for engines as said above. (Because the intake is so small for the 200/300.)

  3. It has really poor climbing skills.

I mean, its not a bad plane, but does have a few things that doesn’t make it the best long-range plane.


It’s not underpowered, per se, as it’s takeoff length is the same as some other planes you wouldn’t consider underpowered, namely, the 777-300ER (10,000 feet), and is less than some other planes (777-200ER, 11,000 feet). It’s power to weight ratio, however, is on the lower side.

Airbus A340-300: 136,000 pounds of thrust / 610,000 pounds MTOW = 0.223

Boeing 777-300ER: 230,000 pounds of thrust / 775,000 pounds MTOW = 0.301

Airbus A320-200: 54,000 pounds of thrust / 172,000 pounds MTOW = 0.314

Boeing 787-9: 142,000 pounds of thrust / 560,000 pounds MTOW = 0.254 (Widely regarded as a good climber and high cruiser, you see them at FL400 at the start of a long flight)

Airbus A330-300: 142,200 pounds of thrust / 533,500 pounds MTOW = 0.267

Boeing 767-400ER: 121,200 pounds of thrust / 450,000 pounds MTOW = 0.269

Boeing 757-200: 84,000 pounds of thrust / 255,000 pounds MTOW = 0.329 ← Overpowered lol

@schyllberg It’s the same type of engine on the A320 and A340-300, but the A343 carries 5Cs and the A320 5Bs, the 5Cs produce 40% more thrust, so it’s not as awful as you might think.


Nice summary! Pretty hard to argue against that :)


Honestly, I had absolutely no idea this was the case. Pretty cool


That’s a first, considering you’re a bigger nerd than i am :)


Thay actually have the same engines as the md90

I know, I meang to write also
Thanks btw


The MD90 engines are IAE engines not CFM…


You’re right, I think what he meant to say was the same engines that can be on the A320, as it does mount the IAE V2500s, the CFM just slipped in there