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General Electric HTRE-3 Nuclear Jet Engine

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21–30 of 71 posts

Re: General Electric HTRE-3 Nuclear Jet Engine

#23

As far as I can tell, aircraft and space nuclear propulsion still hasn't actually be used in flight, right?

Reactors have been flown and made critical in flight, but never used to provide power for aircraft propulsion. The Soviets got the closest, but they abandoned it as well.

Recently Putin has revived a nuclear powered cruise missile design. Status is unknown publicly, but it is believed to have been set back by a major test failure and contamination event.

Today, one can imagine solving the crew shielding problem of these large, nuclear powered bomber concepts by simply eliminating the crew and foregoing most of the requisite shielding. Had that been possible at the time these concepts might have been deployed.

Re: General Electric HTRE-3 Nuclear Jet Engine

#25

Earlier quoted context omitted.

And for scale that’s circling the earth three times.

...at ground level.

The correction for cruising height would be insignificant.

A ram-jet is an air-breathing engine and would be confined to the atmosphere. Even a 60km cruising height (which is much higher than what would be used) would only correspond to a 1% increase in flight path circumference compared to the surface value of 40.000km.

Re: General Electric HTRE-3 Nuclear Jet Engine

#26

Earlier quoted context omitted.

And for scale that’s circling the earth three times.

...at ground level.

Over enemy territory, ground-level flight was considered a feature, as the passing missile would shred the ground with sonic shockwaves, and bake it with radiation from its unshielded reactor.

One of the most evil military designs ever conceived.

Re: General Electric HTRE-3 Nuclear Jet Engine

#27

Earlier quoted context omitted.

...at ground level.

The correction for cruising height would be insignificant. A ram-jet is an air-breathing engine and would be confined to the atmosphere. Even a 60km cruising height (which is much higher than what would be used) would only correspond to a 1% increase in flight path circumference compared to the surface value of 40.000km.

I think the GP might have meant that Mach 3 at ground level is even more technically astonishing - a lot of the historial benchmarks for airspeed (mach 2 fighters and interceptors, the SR71's mach 3) were only valid at very high altitudes were the atmosphere is sufficiently thin to make the achivement teneable from a drag and heat-flux perspective. To cruise along at Mach 3 at sea level is a quite astonishing display of brute force.

Re: General Electric HTRE-3 Nuclear Jet Engine

#28
post #19

Earlier quoted context omitted.

The RTGs on the Voyager spacecraft weigh 38kg. They initially produced 160 Watts. That sounds like a no-go to me.

I wish Toshiba would have actually sold that RTG laptop battery. Imagine never having to charge!

On the other hand, imagine carrying in your bag a heater you can never turn off.

Re: General Electric HTRE-3 Nuclear Jet Engine

#29

I guess the author gets paid by word count. The piece could have been written in one third of the length.

I see you’re getting downvoted, but that was my first, second and third thought when reading the article. It’s suspiciously hand-wavy about the technical details, things are repeated several times and it really does feel like the writer was trying to stretch the article with the help of a LLM.

Re: General Electric HTRE-3 Nuclear Jet Engine

#30

As far as I can tell, aircraft and space nuclear propulsion still hasn't actually be used in flight, right?

Not in flight, but Nerva had multiple prototypes built and tested - the longest run being over an hour long. It was cancelled due to politics, not technical viability.

https://en.wikipedia.org/wiki/NERVA

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