Raider, the early days

Dec 292018

Sikorsky is currently flying the S-97 “Raider” helicopter featuring the ABC (Advancing Blade Concept) rotor. ABC rotors look like conventional coaxial rotors, but differ in being structurally stiff and inflexible. The idea is that ABC rotors allow faster flight: in a conventional single-rotor helicopter, the faster airflow means that on one side of the rotor disk, the “advancing blade” slams into the air at a very high speed, potentially generating a lot of lift. But on the other side of the disk, the “trailing rotor,” which is moving aft at a speed not far off from the airflow, generates very little lift. This of course imbalances the aircraft and limits forward speed. The ABC system, by having coaxial rotors, make sure that there is always balanced lift. The S-97 is not the first helicopter that Sikorsky has built with ABC rotors; the S-69 flew in the 1970s, reaching a top speed of 260 knots. But it suffered from serious vibration issues and did not lead to a production aircraft. The S-97 seems to have fixed most of the issues, and it is hoped that a production contract may eventually come.

The ABC concept dates back *at* *least* 52 years. Below is an illustration from 1966. Interestingly this design more closely resembles – at least superficially – the S-97 than the S-67. The S-69 used two turbofan engines to provide forward thrust, while the S-97 used, like this illustration, a pusher propeller.

Northrop artificial-g space station art

rockets, space station, spacecraft No Responses »

Dec 262018

A piece of concept art circa 1960 depicting a Northrop concept for a space station. Not much to say about it as there are no good scale references, nor do I think I have anything else depicting the station. It is, however, not dissimilar from a lot of other space station concepts of the time… replace the four “habitat” cylinders with a single torus, and this would be pretty much every space station from the Colliers series until the Manned Orbital Space Station concept from the early 60’s.

APR Historical Documents: December 2018

fighter, hi-rez, launch vehicles, Patreon, research, rockets, VTOL No Responses »

Dec 242018

2018-12 Rewards are now available for downloading for APR Historical Documents subscribers. This month the rewards include:

1: A large document: “Sea Launch and Recovery of Very Large Rocket Vehicles,” a 1962 Aerojet report on the sea Dragon concept

2: “Ryan Aeronautical Company Plane Portraits,” information, photos and three-views of a sizable range of Ryan aircraft, manned and unmanned

3: “Nova,” a blueprint of the NASA “Saturn C-8” launch vehicle with 8 F-1 engines

4: CAD diagrams: Star Raker scrap views

If you are interested in signing up, you can do so either at Patreon or directly through PayPal. Signing up now makes you eligible for rewards starting with the *next* months rewards. The directly-through-PayPal system is new; it would probably be best to sign up after the first of the month.

Anyone recognize this Navajo model?

bomber, nukes, rockets No Responses »

Dec 222018

I was sent this photo of a large scale model of the North American SM-64 “Navajo” two-stage cruise missile. the model, largely made from clear plexiglas, was some years ago on display in a Quonset hut at the Planes of Fame Museum in Chino, California. Sometime after this photo was taken the museum was shut down, reworked and re-opened, and after that the museum was no longer in evidence. The photographer wishes to know what became of this model. Anyone know?

APR Monthly Historical Documents Program

hi-rez, Patreon, Patreon catalog 2 Responses »

Dec 182018

For some years I have been operating the “Aerospace Projects Review Patreon” which provides monthly rewards in the form of high resolution scans of vintage aerospace diagrams, art and documents. This has worked pretty well, but it seems that perhaps some people might prefer to sign on more directly. Fortunately, PayPal provides the option not only for one-time purchases but also monthly subscriptions. By subscribing using the drop-down menu below, you will receive the same benefits as APR Patrons, but without going through Patreon itself. The APR Patreon itself will continue; this is just an alternative for those who wish to go a different route.

Shuttle-C art

launch vehicles, rockets, space shuttle, space station, spacecraft, US Launcher Projects No Responses »

Dec 122018

The Shuttle-C of the late 80’s/early 90’s would have carried a whole lot more to orbit than the Shuttle Orbiter, but would not have been quite as capable of precise maneuvering as the Orbiter. Consequently, it might get close to a space station, but it would be unlikely to dock with it unless it was moved into position with secondary orbital maneuvering vehicles or grabbed with manipulator arms. This artwork depicts a Shuttle-C standing off some distance from a space station, with the cargo being shuttled over with an OMV.

The Shuttle-C was described and illustrated in US Launch Vehicle Projects #4.

Early nuclear-electric spacecraft

nukes, rockets, spacecraft 2 Responses »

Dec 072018

A NASA model circa 1959 illustrating the general configuration of a nuclear-electric spacecraft for the exploration of Mars. While apparently not meant to represent a serious design proposal, the general configuration is much the same as those created decades later. It features a nuclear reactor at the nose, a long boom with a pair of radiators to get rid of the heat produced by the reactor, and payload at the tail. Payload includes crew areas and an indistinct lander. The ring at the rear is the “propellant accelerator,” which is not described; presumably it is a structural ring holding a bank of ion engines or the like.

Note that the radiators are tapered. This is common in such designs: the gamma ray and neutron shields behind the reactor only block a relatively small portion of the emitted radiation. The radiators fit within that shadowed cone; if the radiators projected out into the unshielded volume, not only could the radiation do some damage to the structural materials it would also heat them up… defeating the whole point of radiators.

This basic layout would still be applicable today, with the main difference being that the engines might well be located elsewhere, firing in a different direction. The reactor could well be at the tail; leaving the engines where they are would turn the long boom into a structure in tension, meaning that the reactor would be “hanging” down. This would be structurally more efficient… after all, the reactor could certainly hang from a string, but a ship could hardly push on a string. Or the engines could be located near the ships center of gravity, firing “sideways.” This would be trickier for the boom, but if the engines are indeed low-thrust ion engines, the forces involved would be almost negligible. Or with a similar arrangement the ship could be made to tumble end over end; with the engines at the CG they could continue to fire “sideways” while the crew enjoyed at least some measure of artificial gravity.

PDF Review: “Neptun,” the German Heavy Lift Launch Vehicle

launch vehicles, nukes, Patreon, PDF Review, rockets, spacecraft, transports 2 Responses »

Dec 042018

In the late 1960’s H.H. Koelle of the Technische University Institut Fuer Raumfahrttechnik in Berlin devoted considerable effort to studying a reusable heavy lift launch vehicle. A good, well-illustrated report was put out in 1968 covering the design:

Entwurfskriterien fur groBe wiederverwendbare Tragersysteme (Design Criteria for Large Reusable Space Transportation Systems)

Note that the Neptun was *gigantic.* It was a two-stage ballistically recovered design, unusual in that rather than being circular in cross-section it was hexagonal. The individual propellant tanks were each the size of or bigger than the S-IC first stage of the Saturn V.

A number of payloads were proposed. One was a sub-orbital intercontinental passenger transport, The passenger “capsule” would land separate from the Neptun itself.

One of the more interesting payloads contemplated was a large Orion nuclear pulse vehicle, transported in two pieces (propulsion module in one launch and payload/pulse units in the other). Presumably this would be a NASA Orion hitching a ride on a West German booster; I suspect politics would have negated the likelihood of the West Germans developing a mass production line for nuclear explosives.

This fusion-powered interplanetary spacecraft is also a NASA design, dating from the early 1960’s.

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

Forthcoming

hypersonic, launch vehicles, rockets, spacecraft, spaceplane, US Launcher Projects No Responses »

Dec 042018

A 3D CAD model currently being constructed o the Rockwell “Star Raker.” This is being done in order to nail down diagrams and artwork for a future issue of US Launch Vehicle Projects… and also possibly to serve as the basis of a 1/288 scale model kit.

Saturn S-IV & Dyna Soar

Dyna Soar, launch vehicles, rockets, spacecraft, spaceplane No Responses »

Dec 032018

A magazine ad from 1963 showing the S-IV stage and the X-20 Dyna Soar. The Dyna Soar is shown without its adapter section and Transtage, indicating that it is approaching re-entry (note that it is shown with the canopy heat shield still in place). The Saturn S-IV stage, used on a few Saturn I launches, was smaller than the S-IVB that was used on later Saturn Ib and Saturn V launches, and used six RL-10 rocket engines instead of the S-IVB’s single J-2. Also note the three prominent “ullage rockets” sticking out from the base of the stage. These were small solid rocket motors that would impart a slight forward acceleration to the stage prior to the ignition of the RL-10’s. The acceleration would be high enough and last long enough to settle the propellants into the rears of the tanks. Otherwise the liquid propellants would float around in microgravity and might very well not feed properly into the plumbing system; if a turbopump swallowed a large bubble of gas rather than liquid, it could be destroyed.

The Saturn I/S-IV never launched an actual Apollo CSM, but only boilerplate test articles. Interestingly, the BP-16 test article, launched May 25, 1965, stayed in orbit until July 8, 1989.