Oct 292013

Artwork of a three-stage rocket designed by Krafft Ehricke around 1953. 126 feet tall, it would be capable of orbiting 11,000 pounds of payload into a 600 mile circular orbit. Liftoff weight would be 1.3 million pounds.

The first stage, here being shown dropped, would be parachute recovered. the second stage would be expended; the third stage would be used to built up a space station. If you can’t immediately tell where stage 2 ends and stage 3 begins, it’s because stage 3 is the central cylinder, with stage 2 being wrapped around it. This sort of staging arrangement was considered fairly often in the days before they actually had to build these things.

It would be able to land 3,000 pounds on the moon or shoot 5,000 pound probes past Mars or Venus.

 Posted by at 3:02 pm
Oct 252013

In 1968, Boeing (manufacturer of the S-IC stage of the Saturn V) put out an illustration of advanced derivatives of the Saturn V. Published in the XIXth International Astronautical Congress, these included the Saturn V-25(S)U, which was a stretched Saturn V with improved F-1 and J-2 engines, with¬† four 156″ diameter solid rocket boosters; the Saturn V/4-260, which used the same improved¬† Saturn V, but with four 260″ diameter solid rocket boosters, with additional first stage liquid propellant in tankage ahead of the solid boosters. Additionally, the payload shroud could be increased in diameter from ten meters to 78 feet,and up to 290 feet in length. Further included was the Saturn V-XU, which was four improved Saturn V’s clustered together (both first and second stages), with a payload shroud 86.5 feet in diameter and 240 feet long; and an all-new Post-Saturn concept with a 75-foot-diameter core vehicle with optional 260″ diameter solid rocket boosters (up to twelve) and a payload shroud up to 120 feet in diameter. A payload of up to 4.2 million pounds was envisioned.

Two length options were shown… 410 feet and 500 feet. The 410 foot-long vehicles could be assembled within the VAB; the 500 foot-long vehicles would require that the payload be stacked onto the vehicle outside the VAB using a new crane mounted to the VAB roof.

 Posted by at 11:23 pm
Oct 232013

Two notional concept for “nuclear batteries were shown in a Defense Science Board report:

nuclear batteries

The upper concept shows something of a conventional radioistotope thermionic generator, but in small scale. Within it is a 1-cubic centimeter chunk of material infused with alpha and/or beta emitter; the radiation is emitted and absorbed within the chunk, raising the temperature to 1000 Kelvin. A “photonic crystal” captures the blackbody radiation (which in this case would be well into the visible at that temperature) and deposits it onto a thermophotovoltaic cell, where it is converted to electricity. The insulating shell keeps the exterior temperature to about 25 degrees C.

The lower design uses a “jelly roll” configuration with thin flat sheets of alpha and/or beta emitter sandwiched between a sheet of quantum dots, which directly converts the radiation to electricity.

Both designs seem to be made for the same requirements, would produce one to five watts for several years. The radioactive material would be americium or plutonium-238. Pu-238 is a strong alpha emitter, and produced about 0.39 of a watt per gram, so several dozen grams might be needed, depending on efficiency. The only real use for Pu-238 is radioisotope thermionic generators, used on spacecraft; these nuclear batteries would be quite similar. The sad thing is that the US stopped producing Pu-238 in 1988; we now buy it from Russia… but even they have stopped producing it. NASA and the DoE are trying to restore production at a rate of 1.5 kilos or so per year. Since these “nuclear D-cells” are specifically for military applications, restoring manufacturing capability would seem to be needed as a single D-cell would consume maybe 1% of the annual NASA/DoE production.

Americium-241 produces 0.12 watts/gram, substantially less than Pu-238. More importantly, it’s also a neutron emitter, which is obviously bad news for the guy carrying a dozen of these batteries on his belt to power his GPS system, radio and phased plasma rifle in the 40 Watt range.

 Posted by at 10:55 am
Oct 192013

An interesting design for a roadable aircraft:


See more & bigger drawings of this vehicle HERE.

For operations on the ground, it appears that the nose wheel (or nose treads, for off-road use) would be powered, while the prop would continue to provide thrust. Given Russian experience with aerosani, this is hardly surprising.

The idea of a roadable autogyro is neither new nor particularly silly. One such vehicle, the Pitcairn AC-35, was tooling around the streets of Washington, D.C. in the 1930’s:

[youtube nW9tBgmIFEU]

And, perhaps vastly more interestingly, a new roadable autogyro, the PAL-V, may soon be tooling around the streets of the less-overly-regulated parts of the world soon.

[youtube eyz8GwHFaqk]


 Posted by at 6:08 pm
Oct 172013

Very little has emerged from the Strategic Defense Initiative days revealing *actual* weapons designs. With the exception of some of the Brilliant Pebbles and Zenith Star designs, almost nothing apart from unreliable artwork has been released. On occasion, though, bits have come out. Three neutral particle beam satellite weapon concepts were shown, in low-rez and frustrating detail, in a report on power systems for SDI use.

The Martin-Marietta NPB concept:

Martin NPB

The Ge/Lockheed NPB concept:


GE Lockheed NPB

The TRW concept:


The drawings are too small to glean details such as full-scale dimensions, or even get a really good handle on layouts. The GE/Lockheed design seems to come equipped with large panels, presumably radiators, held within a triangular cross-section framework. The Martin and TRW concepts appear to be roughly cylindrical. And unlike the majority of the artwork produced for public consumption, here you can make out the nuclear reactors meant to power the systems.

While dimensions are either unavailable or illegible in these illustrations, two show the SP-100 reactor and associated radiator system. The radiators change from illustration to illustration of the SP-100, so cannot be firmly relied upon as a scale reference, and the Sp-100 reactor itself is little more than a dot, but this illustration of the SP-100 should help to give a rough idea how big it, and by extension the NPB concepts, were going to be.


 Posted by at 3:29 pm
Oct 102013

Another space-based anti-missile system contemplated for the Strategic Defense Initiative was the neutral particle beam. Specifics are exceedingly thin as befits a concept that sounds a *lot* like science fiction.

In practice, the system is a particle accelerator that ionizes hydrogen atoms, grabs them with massively powerful magnetic fields and accelerates them to near light speed. At the end o the weapon, extra electrons are stripped from the atoms, making the hydrogen atoms electrically neutral. This makes them largely impervious to natural and artificial magnetic fields, so they go where you aim ’em and can’t be readily shielded against. However, atmosphere rapidly scatters the beam, so space basing is really the only option. Unlike a laser beam, a mirrored surface would not faze a neutral particle beam. In fact, much of the damage would be done *within* the target, as the hydrogen atoms would penetrate some distance before being stopped and depositing their kinetic energy as heat.

Most of the artist impressions of NPB weapons that I recall showed U-shaped accelerators. By folding the accelerator in half, the spacecraft would be more compact. The energy requirements meant that nuclear powerplants were needed, but the power requirements – billions of Watts for a tiny fraction of a second – would make the power storage and supply issue entertaining. If that issue is cleared up, firing rates of perhaps thousands of shots per second would be possible.

Heres a terrible-quality image of unknown origin, but shows the basic idea:

npb art

Another illustration, credited to Los Alamos National Lab. Note that what at first glance appears to be solar panels is actually transparent; these are either the result of severe artistic license or depict not solar panels but radiators.

neutral particle beam 2013-10-06

I’ve seen virtually nothing to judge the scale of these systems, but there were multiple references to NPB weapons being very large systems requiring numerous launches and considerable on-orbit assembly. Studies in the early 1990’s indicated that operational NPB weapons would probably not be feasible before 2025.

 Posted by at 5:26 pm
Oct 082013

During Reagan’s “Star Wars” days, concept art of space-based anti-missile systems were cranked out on a fairly regular basis. Much of it was, most likely, pure artistic license with little basis in reality. However, some of the weapon artwork was clearly based on actual engineering, such as the Zenith Star and Brilliant Pebbles programs.

One uncertain design is shown in the painting below. It represents a space-based railgun, apparently capable of firing projectiles at high speed in rapid succession. While attributed to the DoD, the vehicle has “Boeing” painted on it. Unlike a lot of the designs, this one at least has a sufficiency of attitude control thrusters. Power for the system is probably nuclear, with the reactor on the far right, surrounded by conical radiators.

railgun 2013-10-06

 Posted by at 11:48 pm