Apr 212018

APR Patrons contributing more than $10 per month were today sent a 1969 diagram of a preliminary design for what would become the AWACS plane… close, but with eight engines rather than four. This design was illustrated in color artwork from time to time.

And for APR Patrons at the $4 and above level, a diagram of the 777 and scans of a McDonnell-Douglas brochure on the “Med-Lite Family” of launch vehicle concepts have been uploaded to the 2018-04 APR Extras folder on Dropbox:

If you are interested in these and a great many other “extras” and monthly aerospace history rewards, please sign up for the APR Patreon. What else are you going to spend $4 a month on? Taxes?


 Posted by at 8:42 am
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:

  1. Stuff that I can afford. This stuff winds up in the APR Patreon catalog of potential monthly rewards for patrons.
  2. 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.


 Posted by at 12:09 pm
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!


 Posted by at 1:56 pm
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!



 Posted by at 4:23 am
Feb 282018

The L-2000 was Lockheed’s entrance into the mid-1960’s FAA contest to design and develop an American supersonic transport. The FAA wanted the US to have an SST substantially better than the Anglo-French Concorde, with up to 250 passengers and a cruise speed of up to Mach 3 (as fast as an SR-71). Interestingly, the Concorde was not expected to be a long0lived design, but rather was simply going to be the *first* SST, a technology demonstrator, a diplomatic endeavor between historic enemies Britain and France, a flying sales brochure for Angle-French industry. And the Tupolev Tu 144 was an attempt to put something, *anything*, into the air first.

In the end, the FAA selected the Boeing 2707 design, ending the L-2000. And after great promise was shown, politics killed the Boeing 2707, ending substantial forward progress in civil aviation. Since then, air flight has gotten cheaper and more efficient, but it has not gotten any faster… and it certainly hasn’t become more comfortable.

This artwork depicts an earlier configuration with a simpler, less elegant shape.

I’ve uploaded the full rez scans to the 2018-02 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!


 Posted by at 11:03 pm
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.



 Posted by at 3:38 pm
Feb 252018

Almost forgotten these days is the Fairchild XC-120 “Packplane,” the single example of which flew from 1950 to 1952. It was a cargo plane with a difference… the cargo was carried not in the fuselage, but in a replaceable “pod” carried below the flat-bottomed fuselage. It would permit the carriage and easy swapping of specialty pods… surgical units, housing, that sort of thing. An interesting notion, but not interesting enough to merit production.

Like a lot of aircraft, not a whole lot of good diagrams of the XC-120. I found a kinda horrible copy in a report, split into several pieces, and stitched it back together.

I’ve uploaded the full-rez version to the APR Patreon Extras Feb 2018 folder, available to all APR patrons at the $4 level and higher.

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



 Posted by at 10:50 pm
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!




 Posted by at 3:27 am
Jan 232018

Currently winging their way from Ukraine to yours truly are two vintage brochures on the Antonov 225. These were picked up on ebay, purchases made possible by patrons of the APR Patreon. These brochures will in due course end up on the APR Patreon catalog, to be voted for as possible monthly rewards for the patrons.

If you’re interested in helping to preserve this sort of aerospace artifact, and also interested in getting high-rez scans of them, consider signing on to the APR Patreon.


 Posted by at 7:35 pm
Jan 172018

The Soviet Tsar Bomb, dropped in 1961 and with a yield of around 50 megatons (backed down from the design yield of 100 megatons) is acknowledged as the biggest bomb ever tested. But is it the most powerful bomb ever designed, or ever built? I’ve discovered some snippets of evidence that the US *may* have designed, and even built, an even bigger bomb.

Several frustratingly unenlightening reports give bits and pieces of information on a bomb code-named “Flashback.” This device was apparently air-dropped near Johnston Atoll. “Flashback” was designed by Sandia Labs and flown from Kirtland Air Force Base to Oahu, Hawaii and then to Johnston Atoll. There are some Terrible Quality Photos:

The Flashback bomb was so big that it could not quite fit within the confines of the B-52 bomb bay, and required the removal of the bomb bay doors.

Of course, this could have been purely an aerodynamic shape. Or perhaps it was a large conventional bomb, a giant “Daisy Cutter.” Or perhaps it wasn’t an actual bomb as such, but just some sort of science experiment to be dropped from an aircraft. Lots of possibilities. But those possibilities drop away with some of the hints that are provided, such as:


This came from an electromagnetic radiation effects report, describing – seemingly – the effect of radio emissions from the B-52 upon the electronics of the Flashback bomb. Since the bomb projected well below the belly, it was subject not only to very cold temperatures but also to intense radio transmissions from the antennae below the B-52 fuselage, so it makes sense they’d test for that. You don’t want the B-52’s communications to cause the bombs fuzing to go screwy. In this particular test, the parachute was not packed within the tail of the Flashback; instead test instruments were fitted there. More tellingly, “All HE (high explosive) and nuclear components were deleted.” Emphasis mine. Additionally, “A simulator was used to replace the warhead.”

You don’t have a warhead in a science package. You don’t have nuclear components in a conventional bomb. and if this was simply an aerodynamic and mass simulator of a proposed bomb… you wouldn’t remove the nuclear materials, because you wouldn’t have installed them in the first place. You don’t fill a mockup full of jet fuel, after all.

Such details as the weight of the unit and the yield of the device are seemingly not given. But they can be guessed at. A report on testing of the tailfin has this:

I’m not quite sure how that load of 36,000 pounds would relate to any actual forces applied to an actual bomb, but it *may* indicate the weight.

Other reports list the sizes and weights of items to be shipped to Oahu (and then to Johnston Atoll) for the test. Some of them are intriguing… what is “EMPTV?” TV certainly means “test vehicle.” But does “EMP” mean Electromagnetic Pulse? If so, does that mean another bomb-like unit, or just a science package, meant to be *hit* with an EMP to see how it reacts? Or is it a specific EMP generator, to be dropped out of an aircraft? Whatever it is, it weighed 14,500 pounds and was around 221 inches long and perhaps 59 or so inches in diameter, and was quite classified (SRD = Secret Restricted Data… “Data concerning the design, manufacture, or utilization of atomic weapons; production of special nuclear material; or use of special nuclear material in the production of energy“).

And there’s 38,000 pounds of “test equipment,” which could be anything:

There was also this:

Here, the “BTV” is the “Big Test Vehicle,” 25,000 pounds, 309 inches long by up to 76 inches in diameter, also classified SRD. Big as this is, though, it’s possibly not the device hanging below the B-52’s belly; the BTV is referenced several times in a way that seems to make it distinct from the Flashback Test Vehicle. But perhaps they are the same thing.

The Flashback Test Vehicle, fortunately, was shown in a fair diagram of a wind tunnel model. Full scale, it was 297 inches long (not counting parachute pack or what appear to be antennae) and was ~96 inches in diameter. This makes it bigger, and presumably heavier, than the BTV. So 36,000 pounds is not unreasonable.

Other ill-described tests show the Flashback as a much smaller unit than the bomb. This, *perhaps,* is merely the “physics package” of the device. This test, illustrated with one of histories worst-quality photos, was carried out in a very cold high altitude chamber, and shows two more mysteries: the “Companion Test Vehicles,” or CTVs, which are unexplained. Speculating wildly, they might have been designed to have the same ballistic properties as the Flashback, so if you drop them from the B-52 along with the Flashback, they’ll fall along with it, following the same trajectory and staying reasonably close. Perhaps thy had cameras. perhaps they had sensors. Perhaps they had transmitters. Who knows.

And there was also the “UTV.” No further data.

Perhaps the Flashback, BTV, EMPTV and UTV were all different sizes of new gigantic bombs…?

Code names generally have no relationship to the subject, but are chosen essentially at random. One would never know that “Copper Canyon” was a program to develop a scramjet SSTO. Similarly, “Operation Paddlewheel” tells nothing. But perhaps, just barely, “Flashback” might have some meaning. Comparing the Flashback to the Tsar Bomb, it it remarkable how similar they are in terms of both size and shape. One might be forgiven for wondering if Flashback was the end result of someone trying to design a Really Big Bomb based on nothing more than a verbal description of the Tsar Bomb, given, perhaps, by a spy or defector. So *perhaps* this project was a “flash back” to the earlier Soviet design. If so, what was the purpose? Was it to give the United States the same insanely pointless capability? Or was it just to find out what the capabilities and limitations the Soviets had gifted or saddled themselves with?

Using the wind tunnel model diagram, I’ve reconstructed the Flashback to scale with the Tsar Bomb:

As can be seen, the Flashback had much the same configuration, but was substantially “fatter.” Impossible to say if that was because the US designers needed the extra diameter to get the same yield (theoretically 100 megatons), or if Sandia Labs went head and designed themselves an even bigger bang. What use is a 200 megaton bomb? Not much. But then, neither is a 100 megaton bomb, especially one so big that the carrier aircraft essentially has to *lumber* to the target all the while carrying the worlds largest bullseye.

As always, if anyone has any further info, I’d love to see it.

PS: I’ve taken the Flashback model and have turned it into 2D CAD diagrams, including scale comparison with the Tsar and showing it stuffed into the B-52’s belly. This diagram will be one of this months rewards for Patrons of the APR Patreon. A simplified version will be included at the $5 level; the full diagram will be in the $8 level rewards package. So if you’d like access… sign up for the APR Patreon.


It’s good to get a fresh perspective. Sadly, the perspective emailed to me was that the Flashback sure looked like a missile nosecone. So I pulled up the Flashback diagram I made from the wind tunnel model diagrams and put the RV from the Titan II ICBM on top of it. It’s not an exact match, but it’s distressingly close. If it wasn’t for the noticeably larger radius of the Flashbacks nose, I’d say it was spot-on… the outer diameter and angle are incredibly close matches.

So…what would be the point of that? Some sort of science experiment, clearly, rather than a weapons test. But what point would there be in dropping a Titan RV from a B-52? Why dangle it from a chute? Why add the heavy tail & fin assembly?

If it turns out that this was an experiment with the Titan RV, that would be less interesting than the revelation that the US developed a 50 to 100 megaton nuke. But it’s still interesting. Just not *as* interesting.

 Posted by at 9:31 pm