The biggest jet engines ever seen are set to roar on Boeing’s 777X

seattletimes.com

6 points·mudil··12 comments

I'm a structural engineer, so when I see forces I like to compare them to common forces I design for in buildings.

That engine produces 115,000 lb of thrust. If I take typical rebar, fy=60ksi, so I will need about 1.916in2, which is about 2 #9 bars.

Two engines per plane, so I could hold back the 777 at full power with 4 #9 rebars. Not bad!

The article says 105,000lb.

You're right, it was the GE-90 that produced 115k. Rest assured, however, that the quantity of #9 rebars remains unchanged.

That's pretty cool!

So if you secured 4 of these rebar perpendicular to the direction of the plane and tied a strong rope from plane to rebar, the result would be the plane couldn’t move and the rebar wouldn’t break or bend?

No, I assumed the rebar is orientated as the 'strong rope'.

If the rebar were positioned as you say, they would yield/bend quite easily.

This is bigger but less powerful than its predecessor. Is it a higher bypass engine, sort of like a turbo prop hybrid type thing?

What's the limiting factor re size? This seems an obvious thing to do to increase efficiency?

Rocket engines aren't considered jet engines ???

Nope. Jets use external oxygen; rockets carry or make their own oxygen.

Rockets are jets.

The name "Jet Propulsion Laboratory" dates to 1943. They do rockets. At least 2 years prior to that name change they had worked on JATO, which is "jet-assisted takeoff". The company Aerojet was founded in 1942, making solid-fuel rockets.

au contraire

https://en.wikipedia.org/wiki/Jet_engine#Other_types_of_jet_...

Like many terms in the English language, the word "jet" has more than one meaning. In the context of flight above the surface of the Earth, it refers to an oxygen-breathing device.

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