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jaggederest

Here's another fun one:

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

An unmanned nuclear-powered ramjet designed to spew warheads, with a predicted range of 116,000 kilometers.

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We were lucky, and got ICBMs instead.

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

Well, that's the best setup for the roadrunner ACME missile launcher joke I've ever heard.

...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.

I'm skeptical of such a capability. Even granting the engines the power and durability to do that, what about the rest of the airframe and avionics? How do they prevent those from being baked if not outright melted? The SR-71 required a substantial engineering effort to withstand the shock heating at that speed but the SR-71 flew very high in thinned air.

It’s not about physical distance, it’s about drag. Masssively more drag at sea level than in a thin atmosphere, way up in the sky.

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.

> as the passing missile would shred the ground with sonic shockwaves

Reminds me of this “oopsie”:

> Three-quarters of the windows in an eight-block area of downtown were shattered by a sonic boom accidentally created by the Blue Angels, the U.S. Navy's flying aerobatic team

https://www.kelownadailycourier.ca/news/article_5e48d6a2-f6c...

To be fair, in the wikipedia article they talk about the radiation hazard being minimal and not part of the design - at mach 3 any exposure to the reactor is so brief it doesn't really do damage.

Of course, it going mach 3 at 1000 feet or lower, is going to knock your toupee right off.

Cruise altitude for a ramjet would be between 5 and 20 miles up. The earth has a 4,000 mile radius. There would be no meaningful difference because of the change in circumference because of altitude.

This reminds me of the Bob & Ray satellite. Their plan was to put a satellite into an orbit 50 feet up, and then sell advertising space on the sides of it.

The problem with it was that they realized they didn't even need the warheads, they could just switch the plane to an open cycle reactor over enemy territory, spewing endless radioactivity and making the entire Soviet Union a nuclear death zone for thousands of years.

That's also why it was classified I believe. No one wanted the Soviets to get the same idea.

As someone else already said - there wasn't really any risk of that, the reactor wasn't "shedding" enough radioactive material or even emitting enough radioactivity to be a danger to anyone standing on the ground. Maybe if you made it fly in a loop around one place it would start to add up, but it wouldn't be anywhere on the scale of "making the entire soviet union a nuclear death zone" - you'd need thousands and thousands of these flying across their entire landmass 24/7 for weeks if not months, which

1) is just a stupid idea

2) if you have the capability to do this, you also have the capability to detonate actual nukes which can be tuned to produce maximum amount of fallout if that's your goal.

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