EM Drive

Hmm..., rockets, science, science fiction, spacecraft, youtube 7 Responses »

Nov 292016

I’ve not devoted much cogitation to the EM drive, mostly because it just strikes me as bunk. There has recently been some renewed interest due to the appearance of a peer reviewed paper that seems to back up some of the claims… but when the thrust level for 100 watts is measured in *micro* newtons, I just can’t scrape up much interest. Especially when the guy behind the idea was claiming that it would be able to power flying cars (capable of VTOL) and space launch boosters, requiring an improvement in T/W on the order of ten to a hundred MILLION times. And, oh yeah, overturning the laws of thermodynamics. Whenever something claims to do that, I tend to tune out.

If the EM drive actually works (and it seems more likely that it works like a radiometer), then it’s kinda like everything else that has ever been touted as actual functioning magic. Yeah, sure, great, you can bend that spoon with your mind. But look at the effort required; using magic, you’re doing it the hard way.

Here is a good if lengthy explanation of why the EM drive most likely doesn’t work, and even if it did, why it sucks:

PDF Review: Gunfight at the Lunar Corral

awesomeness, history, Patreon, projects, rockets, science, science fiction, spacecraft, weapons 15 Responses »

Nov 252016

In 1965, the US Army briefly examined a need they didn’t know they had: firearms for use in space and on the Moon. The US Army Weapons Command in Rock Island, Illinois, put out a brochure detailing some ideas for lunar weapons… “The Meanderings of a Weapon Oriented Mind When Applied in a Vacuum Such as on the Moon.” While not a detailed engineering study, it nevertheless provides and interesting look at the sort of weapons that might be developed for use in a low gravity space environment.

Conventional firearms would work just fine in space… at least for a while. A vacuum would cause most lubricants to outgas and turn to waxy solids or hard rubber-like crud. The extreme differences in temperatures between sunlit and shaded would cause many metals to warp and mechanisms to seize up. And there’s always the possibility of vacuum welding, where two similar metals will simply stick together, fusing into one. And recoil that gives a shooter a good kick on Earth might knock them over on the Moon, or send them tumbling in freefall. The authors described these problems and pointed out potential solutions. Additionally, they provided a number of notional concepts for hand-held weapons, ranging from modifications to the normal sort of firearm, to guns powered by springs (with, it must be said, rather optimistic muzzle velocities) to gas-guns and handheld mini-rocket launchers. It’s odd that the Gyrojet was not included. A laser weapon is said to probably be just the thing, but development of such a thing would take 20 years. A man-portable laser weapon capable of doing useful damage in a combat situation remains sadly unavailable.

Note that the weapons have quite unconventional ergonomics. Some don’t even have proper pistol grips; those that do have triggers roughly the full length of the grip. This is so that a space-suited hand can squeeze the trigger, something very difficult for a conventional single-finger trigger.

The brochure ends with several pages of useful math, providing calculations for ballistic range in other gravity fields, penetration capabilities and muzzle velocities and gas pressures.

The report can be found here:

https://assets.documentcloud.org/documents/3038458/The-Meanderings-of-a-Weapon-Oriented-Mind-When.pdf

Much more aerospace stuff is available via the APR Patreon. If this sort of thing interests you, please consider signing up… not only will you help fund the search for obscure aerospace history, you’ll gain access to a lot of interesting stuff, not available elsewhere.

A Missile Movie Worth Watching

awesomeness, history, nukes, rockets, spacecraft, youtube 1 Response »

Nov 222016

This USAF film report “Aerospace Systems Program Highlights” from 1961 describes the current state of the Atlas, Titan, Minuteman and Blue Scout programs. Basically, there’s nothing in it that *isn’t* interesting. Four stars, would watch again.

Pax Orionis Update

blather, drawings, My Fiction, news, Nuclear Pulse Propulsion, nukes, Patreon, Pax Orionis, rockets, science fiction, spacecraft 2 Responses »

Nov 222016

Due to other commitments, progress has been slow on Pax Orionis. Still, a few days ago I posted a new piece, “Birth of the Bomb Part Two,” for Pax Orionis patrons. This is the second of a two-part newspaper article… the first described an event in the 1990s – well after the Great War – that led to Orion spacecraft becoming far more economical. In the second part, a reporter catches up with the people responsible. Excitement! Adventure! Inadvertent multi-kiloton nuclear detonations! Death from above! What’s not to like?

As with all Pax Orionis tales, each part comes with two bonuses: a technical diagram describing some piece of technology important in the Pax Orionis universe, complete with both in-universe and factual descriptions; and a small newspaper or magazine article that, when all put together, tell an important part of the Pax Orionis backstory.

If interested – and why the hell wouldn’t you be – check out the Pax Orionis Patreon:

https://www.patreon.com/PaxOrionis

There are two level of patronage… $1 and $2. At $1, you get a new story when it comes out. At $2, you get the story, the tech diagram and the article.

Any Pax Orionis patrons who have read the most recent story, feel free to leave a comment. Praise or constructive criticism or anywhere in between.

Lifting Body Mockup Photo 2

aircraft, history, models, projects, rockets, spacecraft 5 Responses »

Nov 172016

Here’s another photo of the lifting body mockup I showed a month ago. Here you can see that the full display – apparently a USAF public relations item – included a more or less full length booster, presumably a Titan II. It’s not the best angle, but it *kinda* looks like this might be just the first stage of the Titan II (or a round tube resembling one) without a second stage. It’s doubtful that there was ever a plan to launch a one-man lifting body atop a single Titan II first stage; it would be distinctly suborbital, and without some deep throttling the acceleration would probably be pretty crushing.

When i last posted this, I mentioned that photos of this were shown “many times.” I wrote that because I remember seeing such photos… but once I started actually looking for them they turn out to be rather hard to find. I imagine I must’ve seen the photos in 1960’s magazines or such. Two more not terribly helpful photos are available HERE and

Book of General Plans

art, awesomeness, blather, Crazy, drawings, Nuclear Pulse Propulsion, rockets, science fiction, spacecraft 11 Responses »

Nov 172016

It will, I imagine, come as almost zero surprise that I’ve long been a fan of the various “Star Trek” blueprint sets produced over the years by fans and professionals. They range from the “why did you even bother when you had to know you had neither skill nor talent” to the “I want to frame that and hang it on my wall.” In my opinion, just as a matter of aesthetics, the best ones were produced in the 70’s and early 80’s (the original Franz Joseph “Constitution Class” set, the McMaster “Klingon Book of Plans,” the Dreadnought, etc.). These were drafted by hand. The errors are in evidence, inconsistencies can be readily found, imprecisenesses here and there, a whole raft of unfortunate things that were eliminated when people started doing this sort of thing on the computer. And when vector graphics, CAD systems and 3D modeling came in and cleaned everything up, a little bit of the art seemed to go out of the enterprise. Dunno… maybe it’s just me.

So, promptly after pointing out that I prefer hand0drawn over computer aided…. here’s the beginnings of my own stab at the art form, done entirely on computer.

Something I have been working on for quite some time is a series of 2D diagrams of the “Messiah” spacecraft from Deep Impact. This is an outgrowth of the 3D CAD model of the Messiah I made for Fantastic Plastic (I gather there were some hiccups in the process, but I understand that things are back on track) a year and a half ago. This is the very definition of a “back burner” project; it’s not a secondary effort, not even a tertiary effort. There are paying gigs ahead of it. Still, going in and tapping away at it from time to time is a good way to destress from the other projects.

I’d spent a long time considering what to do with “Messiah.” Options included some sort of book/magazine/thing, or one or more large format (24X36, say) prints, or even cyanotype blueprints (I did in fact make a grand total of two *very* large Messiah blueprints, quite a while back… a year and a half, as it turns out). But I’ve decided to adopt the “Book Of General Plans” format. In this case,a set of prints, say, 11 inches by 36, folded and in an envelope. Retro!

The Messiah would cover about half a dozen sheets, plus or minus. A lot depends on scale. The image below (purple coloring just a drawing aid, will go to black before printing) shows the 2D diagram in 1/200 scale… which is a quite large sheet. Below that you can see a rectangle, 24X36 inches, subdivided into two 11X36 strips. At 1/200, the plan view of the ship will just fit. Thus, there’d be one sheet for the top view, one for the bottom, one for the side, one for the fore/aft. There are also a number of scrap views…the Shuttle/lander in both flight and landing configuration, details of the Orion booster section, an inboard profile, others.

Here’s a quick look at a small fraction of the illustrations created of the lander:

Along with the diagrams there’d also be “in universe” text and data, with my best efforts to rationalize the design. In the case of Messiah… it’s powered by a wandwavy form of nuclear pulse that uses bomblets that are more akin to “nuclear hand grenades,” with explosions that are slightly oblate rather than spherical… justifying the elliptical pusher plate. The large chemical boosters are liquid systems filled with high-energy space-storable propellants… FLOX burning with a kero-boron slurry. The aft boosters look like Energia boosters; the forward boosters look like Ariane V boosters, but in both cases they are much larger than the originals. This was done because… ummm… well, they were in a hurry (so they copied what they had), and they were working in secret (so they made the boosters look like things people had seen before, so if they were photographed at a distance they could be passed off as the more mundane boosters… yeah, that’s it…).

I’m doing this (veeerrry slowly) because I’m just that much of a geek. Anybody else interested? If I have ’em printed off in quantity, I’m thinking of selling them for around $20 a set, on a print run of *maybe* twenty.

After Messiah, there are a number of other designs I’d like to do the same with. 10-meters USAF Orion (real design). 4,000 ton Orion Battleship (Pax Orionis). Helicarrier (Avengers). USS Ascension (from the miniseries of the same name… oy, the monkeymotions to rationalize that).

Valerian and the City of a Thousand Planets

art, awesomeness, science fiction, spacecraft, youtube 11 Responses »

Nov 102016

And now for something completely different… the next movie from Luc Besson, the feller who gave us “The Fifth Element ” (and “Lucy,” “The Family,” the “Taken” series, and “From Paris With Love”), so you know that even if it winds up not making a lick of sense it’ll be damned entertaining nonetheless.

Trump’n’space

news, politics, reshaping the world, rockets, science, spacecraft 4 Responses »

Nov 092016

I can’t help but think that the list of things in the “proposed implementation” is more “hope” than “likely to come to pass.” Trump seems to not be aware that space exists and that it’s the most important, long-range thing that a President can *actually* influence via policy.

What a Trump administration means for space

As a framework, on the whole it sounds pretty good. Whether or not it’ll come to pass… shrug.

Metallic Hydrogen

awesomeness, Hmm..., news, reshaping the world, rockets, science, spacecraft 12 Responses »

Nov 062016

According to theory, if you put hydrogen under enough pressure it will form itself into a solid metal. Metallic hydrogen would have a density a bit greater than water and would be an electrical superconductor. The planet Jupiter should theoretically have an “ocean” of metallic hydrogen surrounding a rocky core. The difficulty is that the amount of pressure required is astonishingly high, higher than can be produced by man except under a few rare laboratory conditions.

On one hand, metallic hydrogen is a scientific curiosity. On the other hand, there is just barely the possibility that metallic hydrogen is metastable. This means that once formed, when the pressure is removed, it will remain a metallic solid. You will have turned hydrogen gas into a chunk of room-temperature metal.

“Metastable” of course means that it is not *entirely* stable. That chunk of metal might be happy to remain a chunk of metal for a billion years. Or someone might whack it with a hammer, zap it with a laser, nuke it with gamma rays, or yell harsh language at it, which would be enough to cause it to unravel itself back into regular hydrogen. Problem is, nobody is quite sure *if* metallic hydrogen is metastable, and, if so, how twitchy it would be. And this is something you’d really want to know. Because unraveling metallic hydrogen would make one *hell* of an explosive, more powerful than anything else out there. Recomobination of hydrogen from the metallic state would release 216 megajoules per kilogram; TNT only releases 4.2 megajoules per kilo. Hydrogen/oxygen combustion in the SSME releases 10 megajoules/kilo.

If things work out just right, metastable hydrogen could revolutionize space launch and space travel. A rocket engine based on pellets of metallic hydrogen detonations could have a specific impulse of 1700 seconds. This compares really well to the 450 or so seconds you could get out of a hydrogen/oxygen rocket engine, and quite well to a solid core nuclear thermal engine like NERVA, which would have an Isp of 800 to 900 seconds. And it would do all that without the need for radiation shielding. This would make SSTO’s almost trivially easy, make trips to the moon and Mars economical.

The problems, of course, are that we don’t know if metallic hydrogen is metastable (and if so, *how* metastable), and of course we don’t have any metastable hydrogen to experiment with to determine these things.

Except… now we do. Sorta.

Observation of the Wigner-Huntington Transition to Solid Metallic Hydrogen

Ranga Dias and Isaac F. Silvera
Lyman Laboratory of Physics, Harvard University, Cambridge MA 02138

A *small*quantity of reflective metallic hydrogen has been created at a pressure of 495 gigaPascals (71,793,680 pounds per square inch, about 4.8 million atmo0spheres) in a diamond anvil. The sample was about 8 microns in diameter by 1.2 microns thick. As of the writing of that paper (published in early October), the sample was being kept under pressure at liquid nitrogen temperature. The next step is to release the pressure and see if the sample remains solid metal.

Several papers and presentations were made a few years ago describing the potential of metallic hydrogen as a rocket propellant. Given the extreme temperature produced by metallic hydrogen going *foom,* it was assumed that the reaction would be diluted with liquid hydrogen or water. This reduced Isp, but increased thrust.

APR Patreon Back Issue Catalog NOW AVAILABLE

aircraft, APR, drawings, drawings&documents, history, new products, news, Nuclear Pulse Propulsion, Patreon, projects, rockets, spacecraft No Responses »

Oct 302016

I’ve been running the Aerospace Projects Review Patreon project for a bit over two years now. Every month, Patrons get rewarded with sets of aerospace history stuff… currently, one large-format diagram or piece of artwork, three documents and, depending on level of patronage, an all-new CAD diagram of an aerospace subject of interest. More than two dozen such packages have been put together so far and distributed. Given that you can get in on this for as little as $1.50 a month (for 125-dpi scans… $4/month for full-rez 300 dpi scans) and you get at least four items, that’s a pretty good bargain compared to the individual aerospace drawings and documents.

Patrons who signed up after the process got underway can now get “back issues” of the previously released rewards packages. A catalog of more than the first years worth has just been posted; each month will see an updated catalog posted for Patrons to order from. So if you are interested, check out the APR Patreon page to see how to sign up; if you are already a patron, check out the catalog here.

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