A 1977 Rockwell concept for how to expand the utility of the Shuttle system: move the payload from the Orbiter and put it in a shroud ahead of the External Tank. This would have allowed for much larger-diameter payloads to be carried. The ET would of course have had to go into orbit with the Orbiter itself. More info and diagrams of this are in US Launch Vehicle Projects issue 1.
A 1952 film describing the turboprop tailsitter. The film apparently had no audio, so a wholly unnecessary bit of “film projector noise” was added.
The film shows some interesting stuff, such as animations of the craft in action, and artists impressions of what must have been early alternate designs including a ducted-fan design and one with an odd delta wing with a cutout for the props.
Side-view diagram of a Boeing concept for a hydrogen-fueled supersonic bomber from 1956. This monster is shown to scale with a North American XB-70. More info and diagrams of this are in US Bomber Projects issue 9.
A NASA illustration of an advanced solid rocket motor concept, dated 1963. The most obvious difference between the “present” and “advanced” design was the buried nozzle. By properly shaping the solid propellant grain, the motor would perform normally but with a minimum of unused internal volume; this allowed the motor to be substantially shorter than the conventional design. This would make the associated interstage section equivalently shorter, lighter and cheaper. And by shortening and lightening the interstage, the launch vehicle would be shorter, lighter and stronger, with slightly sturdier structural dynamics.
The advantages of a more compact motor like this are pretty obvious. The disadvantages, maybe less so. The most apparent disadvantage is the *need* for far more advanced materials. That buried rocket nozzle is shown to be quite thin, thinner than the “present” design, yet it would be subjected to horrifying heating rates on *both* sides. There are few materials that could withstand that and retain any sort of structural strength.
Additionally: the desire is shown for thrust vectoring. Numerous options for that are available for the conventional nozzle… but it would be much harder with a buried nozzle. It might be easiest to simply gimbal the entire motor. Stop/restart capability has been achieved with solid rockets, but neither design show here provides for that. It is a non-trivial feature.
The igniter is show to be a small rocket motor suspended within the nozzle, directing it’s exhaust forward into the bore volume of the main motor. Variations on this sort of igniter are quite common for relatively short and stubby upper stage motors such as these.
A photo of a NASA wind tunnel model of a hypersonic aircraft configuration. The circa 1960 NASA brochure (promoting the organization to college students) that included this provided no further information, but I’m reasonably sure I’ve seen the wind tunnel test report on this, calling it a reusable booster or reusable launch vehicle. If that’s the case, the upper stages and payload were *probably* going to be carried on the things back.
I admit that the USBP series looks kinda… bland. It’s text and line drawings; not a whole lot can be done to jazz that up. Especially since I have no head for graphics design whatsoever apart from layout diagrams.
Still, one reader sent me a mockup of a revised cover of USBP #18:
Things are moved around a little bit, but the obvious change is the addition of color. The suggestion was also made to consider color-coding each title in the USXP series. Just off the top of my head, I came up with:
Bombers: Olive Drab
Spacecraft: Black
Launch Vehicles: Blue on bottom, transitioning to black at the top
Fighters: slightly bluish gray (like the F-15 or F-22)
Transports: ??
VTOL: ??
The USBP#18 cover was re-done to reflect this, thusly:
Thoughts? Is this more appealing?How about color-coding… good idea or not? And if so, what colors?
I tried something vaguely like this once before, with USBP#05.
Or $750/lb. SpaceX pricing for the Falcon 9 and Falcon 9 heavy:
http://www.spacex.com/about/capabilities
For comparison, the Delta IV Heavy costs $375,000,000 with a LEO payload of 28,790 kg/63,470 lbs, or $13,025/kg or $5920/lb.
SpaceX stands a decent chance of monopolizing the launch market in the US. And while the price does not include a Dragon capsule, the US is currently paying the Russians $70 per astronaut to fly on a Soyuz. That’s more than the price of an entire Falcon 9 launch which, with a Dragon V2 capsule, should carry 7 astronauts.
Elon Musk has announced that SpaceX is planning on using a Falcon 9 Heavy to launch a modified and unmanned Dragon 2 space capsule to Mars. In 2018.
Planning to send Dragon to Mars as soon as 2018. Red Dragons will inform overall Mars architecture, details to come pic.twitter.com/u4nbVUNCpA
— SpaceX (@SpaceX) April 27, 2016
Seems the Dragon 2 has been designed to be an all-round planetary lander, supposedly good for “anywhere in the solar system” (oh, yeah, smart guy? Like, the sun? Jupiter? Detroit?). That’s certainly handy, but they’ll need an ascent vehicle if they want to send (and recover) humans.
I’ve never really been much of a fan of the space elevator concept. Not so much that it relies upon nearly magical levels of structural strength (though some new materials are strong enough – at least at small scale – to make the concept feasible), but because it is something of a snail for getting payloads into orbit. If your elevator can climb at a brisk 100 km/hour, and that would be a massive challenge, it will take the elevator about 358 hours to climb to geosynchronous… slightly over two weeks. That’s a couple days in the van Allen belts, so your elevator had better be highly shielded… which means the ratio of payload to climber will be minimal. And then your climber has to either be jettisoned, or it has to make the climb all the way back down. That will be probably several days, during which time you can’t send another climber back up. So you’re probably looking at a turnaround time of around three weeks per “flight.”
Turnaround time can be improved by not going all the way to GEO. Instead, go several thousand miles up, then throw the payload overboard. The higher up you go, the more tangential velocity you’ve have, and the closer to a circular orbit you’ll have. To get into an actual circular orbit, you’ll need to have an onboard propulsion system; the lower your ejection altitude, the more propulsive capability you’ll need. But while this’d speed up the elevator system, it’ll reduce effective payload by *a* *lot.*
Jettisoning a payload puts it into an elliptical orbit with the jettison point being apogee. Perigee rises as the elevator rises; at some point you’ll have an orbit where the perigee is something convenient like 400 km. So all you’ll need is enough propulsive capability to circularize at perigee. But since I can’t be bothered to do the actual math, it seems to me the apogee altitude will be quite high for the elevator, so it might only shave a relatively small fraction off the elevator trip time compared to going all the way to GEO.
Then there’s the problem of actually climbing. How? The cable might be a flat ribbon, millimeters thick by centimeters wide, or it might be actually cable-shaped. But the materials under consideration, graphene and diamond fiber and such, have a little problem: they are virtually frictionless. Run wheels on them all you like, you probably won’t get much traction. Adding a ribbed surface for traction, or adding magnetic materials so a maglev system can haul up the elevator, will add vast amounts of weight to the system.
This video points out some of the engineering issues with the concept:
Now available: two new US Aerospace Projects titles.
US Bomber Projects #18 is now available (see HERE for the entire series). Issue #18 includes:
USBP #18 can be downloaded as a PDF file for only $4:
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US Transport Projects #06 is now available (see HERE for the entire series). Issue #06 includes:
USTP #06 can be downloaded as a PDF file for only $4:
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And don’t forget…
US Fighter Projects #1 and US VTOL Projects #1 are still new and still available!
