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by KingOfCoders 1279 days ago
"35,000 pounds of thrust"

Can anyone compare this to other commercial and military engines?

4 comments

Air speed is an important aspect in this conversation. The air going into a 747's engines isn't travelling at supersonic speeds. For reference, the Concorde's Rolls Royce Olympus 593 engines did 35,190 lpf and it had four.

https://en.wikipedia.org/wiki/Rolls-Royce/Snecma_Olympus_593

A popular turbofan with civilian fighter jets is the TFE731 with 3,500–4,750 lbf [1] and can be fitted to i.e. the L39 Albatross trainer jet. [2]

Supersonic jets like the F5 might use something like the GE J85 which produces a base 3,500 lbf or 5,000 with an afterburner [3].

[1] https://en.m.wikipedia.org/wiki/Garrett_TFE731

[2] https://en.m.wikipedia.org/wiki/Aero_L-39_Albatros

[3] https://en.m.wikipedia.org/wiki/General_Electric_J85

civilian fighter jet ? Is that a US thing ?
Mostly. Ironically the most popular civilian fighter jet is a Soviet era Czech design (the aforementioned L39).

Even in the US though, they are relatively limited in where they can fly and require an experimental aircraft authorization. It’s relatively impractical in most of Europe because they’re not allowed to fly above populated areas except to take off and land (at least in the US)

You don't actually have to worry about any of this stuff, if you have the money to buy one of these you also have the money to register it in a third country.

>It’s relatively impractical in most of Europe because they’re not allowed to fly above populated areas except to take off and land (at least in the US)

FWIW this is mostly a US problem.

A bit less than an F-35 engine, a bit more than a single 737 engine.
> A bit less than an F-35 engine

Or quite a bit more for a more equitable comparison, the F135 reaches 43 with afterburners, but it "only" reaches 28 dry.

According to TFA, this fantasy doesn't have afterburners (although the Tu-144D didn't either though, and the RD-36-51 is documented at a pretty incredible 54000 lbf, then again the 144 was not exactly a cheap and efficient plane).

Google says "The most recent model, the 747-8, has engines that produce 66,000lbs of thrust."