S Air Force's fleet of giant super Galaxy cargo planes air work.

I could feel it in my chest power it takes to get that into the air.

But back in the 19 sixties, the Super Galaxies original designers needed new supersized engines to get it.

But even on something that big, there's a limit to the size of engine it can carry.

They needed to find a way of making those engines bigger without making them bigger.

Hidden away here, among thousands of acres of hills and forest peoples are higher is a testing facility of General Electric, the company that developed and built the stupid Galaxies engines.

A what?

This is a specialized work so we can feel the air is cracking with precision.

In here, I'm here to meet Steve skate over one of the engineers responsible for designing and maintaining the big planes.

Jets?

Is this actually offer Super galaxy?

It iss um, this engines actually been on wing for over 12 years.

How long is this gonna be in for what I suspect is quite expensive surface.

We target 90 days.

I suspect it will take longer, but that's our target.

Depends what you find in there.

Yes.

Okay, well, look, this is a change.

And it is to the layman, just a mass of pipes and tubes.

It was like the back of the most complicated washing machine ever.

A regular jet engine makes his air and fuel in a combustion chamber and then propels the resulting exhaust out the back.

That's what delivers thrust.

But General Electric came up with a radical modification.

They added a huge turbo fan in the front which drives more air at high speed into the combustion chamber.

On crucially, even more air through a bypass chamber around the outside of it, forcing air around as well as through the combustion chamber made these high bypass engines more powerful than ever before.

Revolutionized.

This is hauling in huge amounts of it.

Correct.

About 42 tons of air per minute, 42 tons of already goes pulled in through that and I can see around the outside.

That's where it doesn't go into the engine.

So this is the bypass, correct.

So for this particular engine, the ratio of air that bypasses the core, and it goes through.

The fan is eight.

Toe one was a part of here, toe one in this.

So the majority of the air is going around the engine then extinct the baron with more mass to put your foot.

And this was a massively significant development in in aviation engines.

It's virtually the configuration that's on every commercial aircraft today.

So I think there's a figure that at any given moment that something like one of the quarter 1,000,000,000 people in the air commercial flights and nearly all of the big powered by engines at this time, that's correct.

So it moves the world.

Yes, Before any jet engine goes into service, it has to be rigorously tested.

But they're so powerful that can only happen in enormous buildings constructed to withstand the colossal forces involved.

One of the most specialized rooms I've ever been in.

It is only for text injected how to avoid, say, Olsen.

It's also probably this isn't the best place to be when it stops.

So I'm making my excuses and heading to meet Michael J.

Adana in the control room.

So what do you have to do to try and test these engines to closely monitor no fans being forced being, Did you t fuel pressure?

Um, and ar thrust.

How did they test they test to £57,000 of thrust 57.

The high bypass innovation was revolutionary.

It delivered all the thrust that plane needed without adding any weight.

There is no replacement plan for the C five Super galaxy, and it's been future proofed to 2045 by which time?

Beginning on for 100 years old.

Best part of a century of servants carrying out critical missions in war and peace across the globe.