spacecraft – Page 25 – Aerospace Projects Review Blog

Lunar Exploration Systems for Apollo

launch vehicles, Patreon, rockets, spacecraft No Responses »

Apr 192018

For the APR Patreon I try to acquire as much interesting aerospace documentation as I can, and these items fall into two categories:

Stuff that I can afford. This stuff winds up in the APR Patreon catalog of potential monthly rewards for patrons.
Stuff I can’t hope to afford.

There’s a lot of the latter category of stuff. Sometimes it’s because the item has a ridiculously high Buy It Now price or starting bid, or because the item will be popular among bidders, or because it’s *really* good/big and thus worth every penny. But unaffordable is unaffordable.

However, there is an option for “stuff I can’t afford:” crowdfunding. I’ve done this a number of times with considerable success, and I’ve just done so again, winning a trio of General Dynamics documents describing a 1965 program to develop a logistics system for extending the Apollo lunar exploration program:

This set of documents was just much too expensive for an individual (well, I’m sure Jeff Bezos or Elon Musk wouldn’t have flinched), but with a group of like-mined funders it came in at $30 per person. So what happens now:

1: I wait for it to show up in the mail.

2: I make a complete set of scans in 300 DPI grayscale (and color, where appropriate) and convert to PDFs

3: I make the scans and PDFs available to funders, generally via Dropbox

4: I find an appropriate archive for the documents, and then donate the originals to them.

5: And that’s it. The files are shared with the funders, but do not appear on future APR Patreon catalogs or as purchasable, downloadable “Diagrams and Documents.” What the funders choose to do with their scans & PDFs is up to them.

APR Patrons get alerted to each of these occasional “crowdfunding opportunities.” So if you’d like to participate, please considered signing up for the APR Patreon.

Hovertank and spaceplane

hi-rez, Patreon, spacecraft, spaceplane No Responses »

Mar 292018

Here are two presumably wholly unrelated pieces of aerospace artwork. At least I *hope* they’re unrelated…

The first is an anonymous painting of a spaceplane. Doesn’t seem terribly realistic; most likely done for advertising purposes (I wonder if the “7-11” might indicate a relationship to the chain of the same name). The print arrived damaged, as you an see; the paper was thick and *really* brittle and really didn’t appreciate being rolled up. If anyone knows anything about it, feel free to comment.

The second is concept art from Bell Aerospace illustrating an amphibious troop carrier for the Marine Corps. The design of the assault vehicle is fairly ordinary as such things go, except for one detail: it could turn into a hovercraft and float across the surface of the water, rather than plowing through it. No further details provided, so I don’t know if the hover-skirts were deployable and retractable, or if they were simply dropped when the vehicle got to shore. The latter would certainly seem more economical.

I’ve uploaded the full rez scans to the 2018-03 APR Extras Dropbox folder, available to all current APR Patrons at the $4 level and above. If you are interested in this and a great many other “extras” and monthly aerospace history rewards, please sign up for the APR Patreon. Chances are good that $4/month is far cheaper than your espresso/booze budget!

HL-20

rockets, space shuttle, space station, spacecraft, spaceplane No Responses »

Mar 292018

An old NASA video describing the HL-20 lifting body. In the 90’s NASA spent a lot of time and trouble trying to get an HL-20 built for a Personnel Launch System, a vehicle smaller than the Space Shuttle but capable of carrying as many passengers and riding a much smaller launch vehicle. For transporting passengers to and from the Space Station, it would have been much more economical and sensible than the Shuttle. And while the HL-20 was never built, the basic geometry has survived in the form of Sierra Nevada’s Dream Chaser, which *might* actually fly to space someday.

Solar Powered Spacecraft

rockets, spacecraft No Responses »

Mar 272018

A piece of late 1950’s promo art from Rocketdyne illustrating a spacecraft with a solar thermodynamic powerplant. This should not be assumed to be an actual design, but much more likely just more or less pure illustrative art.

The craft is shown with a great parabolic solar reflector, the sunlight heating an element at the focus. In an actual design, most likely a working fluid would be pumped through this and boiled, the resulting high pressure gas blowing past a turbogenerator and then into a heat exchanger or directly into a relatively vast radiator. The gas would be cooled back to liquid and recirculated. Note that no such radiator is in evidence. Sometimes early designs utilized radiators built onto the shadow side of the reflectors. The craft appears to be over Mars, based on the hints of canals that are kinda visible. The ship has a parabolic radio dish on a boom below; the upper boom would seem to hold a trough, likely a launching platform for a small probe rocket (another cliche in early spacecraft art). At the rear is a boom that appears to hold two banks of ion engines or some other electrical propulsion system. Oddly, the thrusters would seem to be held off well to the side of the craft, rather than actually firing through the centerline (unless that boom is supposed to be projected straight aft and mounted at one end of the bar holding the thrusters, thus putting the centerline of thrust back through the CG of the craft).

PDF Review: Wheelguns in Spaaaace

nukes, Patreon, PDF Review, spacecraft 3 Responses »

Mar 092018

Advanced “space guns,” typically lasers, railguns, coilguns, neutral particle beams and the like, have a problem: power. Nuclear reactors and solar panels can provide power for years at a time, but generally their steady-state power output is only a tiny fraction of the instantaneous power needed when the gun goes off. So to run a weapon that needs many gigawatts for a fraction of a second with a powerplant that produces kilowatts, you need an energy storage system that can convert that energy into power on a moments notice. Things like batteries are great in principle, but their weight is vast and their ability to release power at the high levels needed is generally poor.

Often this has resulted in space weapons that use chemical reactions to provide the power needed. This has meant that the total number of shots that can be fired is strictly limited.

In the 1980’s during the SDI heyday, Westinghouse looked at an alternate approach: rotating hoops. Giant wheels made of advanced composite materials would be spun up over time by a low-power system such as a nuclear reactor, and when needed these flywheels would be electromagnetically braked to generate vast amounts of power as the wheels ground to a halt. The system could be “reloaded” by slowly spinning the wheels up again… assuming the system hadn’t torn itself part.

The weapon shown below is probably largely notional, no masses or dimensions were given. But based on a smaller terrestrial unit (with ten hoops, each 14.5 meters diameter, massing 140,000 kg each, spinning at 1800 RPM to deliver a total of 1 gigawatt for 10 minutes to power anti-missile lasers and such), this can be assumed to be a fairly *vast* construction, far heavier than anything mankind has so far launched into orbit. Obviously such a thing would be impossible to launch as a unit; it would be assembled in space using spools of fibers wound in place. Presumably the weapon itself would be at least somewhat aimable independent of the flywheels… slewing *them* about to aim at a moving target would seem to be an exercise in futility.

This came from the paper “Rotating Hoop, Pulsed-Energy Converter” contained in “Transactions of the Fifth Symposium on Space Nuclear Power Systems.” A PDF of that can be downloaded if you go HERE and click the “PDF” button.

Support the APR Patreon to help bring more of this sort of thing to light!

APR Patreon rewards, February, 2018

bomber, hi-rez, jetliner, nukes, Patreon, rockets, spacecraft, transports No Responses »

Feb 272018

Rewards have been issued to APR Patreon patrons for February, 2018. This month, the diagram is a 1/40 scale B-52B diagram. Normally the diagrams are sent out at full 300 dpi (with 125 dpi for the $1.25 patrons), but at 300 dpi the diagram is simply Way Too Big at over 40,000 pixels wide. Most image viewing programs will simply go “nope”and refuse to even try to display such images. so this month the image is sent out at 200 dpi (still slightly over 30,000 pixels wide), and 83 dpi for the $1.25 patrons. The 83 dpi version is also included for the higher level patrons for easier viewing.

Also: the documents this month include a United Aircraft paper on advanced future space propulsion systems as seen from 1969, and a January 1953 Douglas Aircraft design study for the DC-8. The CAD diagram this month is the Ganswindt Weltenfahrzeug… a truly terrible design for a spaceship from 1899. Terrible though it may be, it one of the first designs that is clearly in the Project Orion family tree…

If you are interested in helping to preserve (and get copies of) this sort of thing, consider signing up for the APR Patreon.

PDF Review: NERVA for both propulsion & electrical power

nukes, Patreon, PDF Review, rockets, spacecraft No Responses »

Feb 192018

The NERVA nuclear rocket, studied throughout the sixties into the early 1970’s, would have been a great way to propel spacecraft. But a nuclear rocket is not the same sort of reactor as is generally designed for use in space to generate electrical power. A NERVA can produce *gigawatts* of thermal energy, energy which is carried away with the high mass flow rate of the hydrogen propellant. Power reactors, on the other hand, are generally designed for several orders of magnitude lower thermal power… a few thermal megawatts, perhaps, to produce a few hundred kilowatts of electricity.

However, the fact remains that a nuclear rocket *is* a nuclear reactor. For most missions it would burn for a few minutes, at most perhaps few hours, out of a mission lasting perhaps years. It is thus a bit of a shame to waste all that potential. So over the decades many studies have been made for using a nuclear rocket as a power generator .

One such study was reported by Aerojet in 1970. The abstract is HERE, the direct PDF download if HERE.

In this study, the NERVA would pump out 1,500 thermal megawatts during the propulsion phase(producing 75,000 pounds of thrust), dropping to 250 to 505 thermal kilowatts during the power generation phase, enough to create 25 kilowatts of electricity. This would be a very low-power, low-temperature use of the reactor, reducing system efficiency… but still, making use of a reactor that was already there, and not noticeably using up the fission fuel in the reactor. The reactor would be run at very lower power levels and hydrogen would flow through a closed loop built into the reactor; the warmed gaseous hydrogen would flow through a turbogenerator to create electricity; the warm hydrogen would then pass through a radiator built on the outer surface of the hydrogen tank itself.

Support the APR Patreon to help bring more of this sort of thing to light!

Martin Space Station

rockets, space station, spacecraft No Responses »

Jan 302018

A fanciful late 1950’s Martin Company illustration of a space station. This rendering features a large parabolic solar reflector to concentrate sunlight onto a boiler to run a turbogenerator for electricity, a hockey-puck shaped habitation section (you might think it was meant to rotate, but there are windows in the floor *and* a group of astronauts seemingly standing on the side of the thing, somehow not getting flung off), some standard 1950’s gee-whiz rocketships and something at far right that I can only describe as “a thing.” Maybe it’s meant to represent the radiator for the solar generators working fluid, but if so, it seems a terrible design. Maybe it’s the death ray.

Nuclear-ion spacecraft

nukes, rockets, spacecraft No Responses »

Jan 142018

A 1966 Aerojet concept for a space probe with a nuclear reactor and ion engines. Note the largish thermal radiator “wings;” such things are usually left off spacecraft in science fiction, but they are a vital part of any nuclear spacecraft. Nukes, after all, are simply heat sources; in order to get useful electrical power out of them, the heat must be used to boil a working fluid which runs a turbogenerator; and the hot gas then needs to be condensed back to a liquid by radiating the heat way to space. And thermal radiation is a terribly slow and weak process, necessitating large radiators. Electricity can also be created with thermionic systems, which generate electricity across a thermal differential… hot on one side, cold on the other. But unless the cold side it attached to some radiators, the cold side will soon be just as hot as the hot side, and then… no thermal differential, no power generation.

Note also that even with a substantial powerplant and the sizable bank of ion engines, acceleration is going to be creakingly slow. Thus you can get away with spindly structures. The reactor itself is the tiny little tin can-looking thing, top and centerline; the U-shaped structure around it is a radiation shield protecting the electronics, structure and radiators from the radiation spat out by the reactor.

Drawbridge orbiter: orbital art

hi-rez, hypersonic, launch vehicles, Patreon, rockets, space shuttle, spacecraft, spaceplane No Responses »

Jan 012018

This piece of art depicts the McDonnell-Douglas “Drawbridge” orbiter in orbit delivering a satellite. Note that the wing are deployed, even though they would be folded up during entry. The geometry of the craft was such that in order to get the cargo bay door open and payloads safely in and out, the wing needed to fold down out of the way.

This points out one of the reasons why you don’t often see a whole lot of “cool” stuff in aerospace… everything has tradeoffs. And needing the wings to constantly go up and down is a bit of a headache. When it comes to spacecraft, mass is a primary priority; the mechanisms needed to deploy the wings weight a lot… never mind the mechanisms needed to retract the wing again. As an example, the real space shuttle orbiter had no landing gear retraction system. And why should it? The landing gear is hardly something the Orbiter would ever need to retract. That could be done by the ground crew without adding weight and complexity to the craft itself.

Note that the Orbiter and the payload here seem to have not NASA markings, but Red Cross markings. I suspect that a number of variants of this piece of art would have been produced with several different markings (NASA and Pan Am being the obvious ones), but why exactly Red Cross? Dunno.

Also note that this might not be an actual “Drawbridge” design, as no extension mechanism for the wing s in evidence. This might be an oversight on the part of the artist; it might be that this was a fixed-wing design. Given the RCS thrusters on the wingtips, this is most likely *not* a Drawbridge.

I’ve uploaded the high-rez version of this artwork (11.2 megabyte 6271×4763 pixel JPG) to the APR Extras Dropbox folder for 2018-01, available to all APR Patrons at the $4 level and above. If you are interested in accessing this and other aerospace historical goodies, consider signing up for the APR Patreon.

Older Entries Newer Entries