Hypersonic Missiles

Why the Hype Around Hypersonics?
Sabbine Hossenfelder

Sabbine is my new favorite YouTuber. I watched one about the 5th Element, er, the 5th Force earlier, and it was fine. She has a blog (BackReAction) where she posts her videos along with transcripts. Most of the videos are her talking, but she does include some graphics that help illustrate the topic. This video includes a clip of a double sonic boom from a Concorde. I had to play it a couple of times in order to hear it. It's really quick, the two booms are like a tenth of second apart. Bang bang.

This is the first explanation of hypersonic missiles that actually explains anything. All of the rest have been nothing burgers. 

The bit about how long it takes a ballistic missile to reach its target versus a hypersonic missile is not complete. If the two devices are traveling the same distance across the Earth, then what she says is true, hypersonic missiles would take just as long as a ballistic missile. However, ballistic missiles are big and difficult to transport, so mostly they don't leave their home country unless they are on a submarine. Hypersonic missiles are smaller (they don't have to carry an oxidizer, which is roughly half of their fuel load, which is what makes up the bulk of the missile), so they could be carried by an aircraft and launched from a relatively short distance away.

Assuming, or course, that they actually make these things work. And then there's the whole hypersonic glider thing. Traveling at Mach 5 you are covering one mile per second. Turn off the engine / run out of fuel and you will glide for a bit, but I would be surprised if you could glide ten miles before you fell to the ground. I haven't heard anything about this.

Previous mentions of hypersonic (3).

Previous mentions of supersonic (many).

Lets Go Hypersonic

Hypersonic Missile Nonproliferation
I've been hearing 'hypersonic' for a few years now. I put up a post about it not too long ago. This is the first time I have heard it mentioned in the context of weapons. I guess I shouldn't be surprised. That's what the military does, try to come up with new weapons. Just because all the jabber was about hypersonic airliners and spaceship boosters doesn't mean the military wasn't planning all along to use this new technology to make a new weapon. Silly me for not realizing this.

The video is kind of interesting, the way they cut from one speaker to another. Makes me wonder if there is some kind of subconscious marketing technique at work here. I mean it all sounds very reasonable, or as reasonable as a discussion about crazy shit can be.

The video is from The Rand Corporation. They used to be a big, important think tank, but I haven't heard anything from them in a long time. Maybe because they were a little slow to adapt to the internet. Or maybe I just haven't been paying attention.

Operations Research is one of things The Rand Corporation does. I had a boss an Intel who had a degree in Operations Research. I never really understood what it was all about. It sounds like a mixture of math and common sense, which I never thought was very difficult and certainly nothing to write home about, but maybe the trick is being able to communicate your mathematical, common sensical ideas, and somebody saw some value in that.

Via World Affairs

Hypersonic

A Russian MiG-31K carrying a Kinzhal hypersonic cruise missile - Russian Defence Ministry/AFP

We've been hearing about hypersonic missiles for a while (years?) now, but it's always been tests or prototypes or designs or funding. This might be the first time I've seen a picture of an operational missile. Aljazeera has the story.

Hypersonic

Hermeus Quarterhorse Mk 1

Hermeus is trying to build a hypersonic aircraft. Sounds like they are aiming for military use. This prototype drone is about the size of an F-16. It only took them a year to build it and get it flying. They're working on the Mk 2 and expect to fly it later this year. This building looks like it might be a wind tunnel.

The Hypersonic Missile Vulnerability That NO ONE Talks About

I dunno, it kind of sounds like nobody has a hypersonic missile that can live up to its hype. At least not yet. 

I suppose that the compulsion to build ever more deadly weapons is ingrained in our society, our minds and our bodies right down to our bones. All driven by the fear that if the 'other guys' got an edge up on us we would be at their mercy, and being as 'they' are heathen, pagan, devil worshipers, we can't expect much in the way of mercy. Probably be put up on stage and dissected. Better to go out in a blaze of glory, am-I-right?

Of course, this compulsion is buried deep within our bones and after you have applied a nice thick layer of civilization over those bones, you might think we live in a civilized society. I am pretty sure we don't, but we like to pretend that we do, we like to pretend that if we all just got our shit together, we could all live in a civilized society. It's a nice dream and its our belief in that dream that allows us to have little bits of paradise scattered here and there around the world.

But our society is not really civilized. All that civilization that's been slathered on our bones is no kind of armor if reality decides to intrude, and it doesn't take much reality to break through that cream puff layer and reach the bones where the killer resides. Wake him up and see how civilized our society is.

Gravity, Part 2

Watched Gravity (Warning: autoplay) again last night. It was just as great as the first time, partly because my memory was playing tricks on me. I distinctly remember Kowalski telling Ryan to open the oxygen valves on the Soyuz spacecraft, but he didn't.


Gravity - Clip (9/11): Shenzhou Re-entry      Since I have been mulling over reentry I paid a little more attention to this sequence. Notice that the capsule is tumbling when it begins reentry, but after it separates from the attached modules, it straightens out and flies right. Posting a question on the reference desk led to Wikipedia's article on Atmospheric entry, where in I found this bit:

The Apollo Command/Service Module used a spherical section forebody heatshield with a converging conical afterbody. It flew a lifting entry with a hypersonic trim angle of attack of −27° (0° is blunt-end first) to yield an average L/D (lift-to-drag ratio) of 0.368.^[10] This angle of attack was achieved by precisely offsetting the vehicle's center of mass from its axis of symmetry. 

10 Short Videos #6228

10 Short Videos #6228

1. Insane Manual Technique to Install Drive Belt on Heavy Rock Crusher! 😱⚙️
2. Funny Cat Moments
3. The Blanket Octopus is a MENACE
4. what are the chances 😭 - cyclist attacked by rabbit
5. Noah the Husky Trying to Climb a Tree || ViralHog
6. Heaven's IT Guy - Exorcism Diagnostics
7. 1980 Farming
8. Talon-A #Hypersonic #Vehicle #Landing
9. Watching the eclipse from 36 000 km up 🌒
10. Do You Know What This Is? OVER 100 Years Old! - Ludwig Obry patent gyroscope from 1895

Science Fiction

Supersonic Roller Coaster-cum-Aircraft patented by an Airbus Group Company
I don't know which is more of a pipe dream: this thing or Fireball XL5. They managed to combine live action and CAD in this video, but the technology to actually build this thing is still decades away. Still, it's nice that people are turning their dreams into digital models.
   Boeing and a group in Australia have been working on a hypersonic ramjet.