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ESA Unveils Re-Entry Module
bmcage writes "The ESA unveiled the Intermediate eXperimental Vehicle, a real re-entry vehicle. Although it will not be reused, it has a better geometry than NASA's Orion or the Russian Soyuz, giving better lift, and control. This is not done by the addition of useless wings, but by using two brakes. Finally a departure from the Apollo design that is actually better?"
Also penguins rely on better geometry and not on useless wings!
Maybe Computers will never be as intelligent as Humans.
For sure they won't ever become so stupid. [VR-1988]
> it has a better geometry than NASA's Orion or the Russian Soyuz, giving better lift, and control. This is not done by the addition of useless wings, but by using two brakes.
In case you're interested: The brakes are controlled separately. One applies to the front directing cilindrical sustainer, the other to the rear main power.
The optimal braking is then executed applying the force in a 3/7 proportion, to avoid unnecessary drifting.
Further investigations are studying the possibility of changing the current power source. So the astronauts don't get so tired.
Bmcage needs to look into what lifting bodies are -- they do not need wings.
Wings were added to the shuttle to respond to the the USAF's crossrange requirements & some of the early shuttle plans looked a lot like this.
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Mostly it is a testbed of the design and aeronautical controls. Looking at the movie's many exploded and shaded CAD views (nice touch, guys), it appears to have no cargo space whatsoever. It doesn't look to me like that's what they have in mind - they just want to show that the flight fundamentals of the design are sound. They can work on building a larger one for cargo and/or humans if they manage this first significant milestone.
So that means it's thread safe?
By doing things like using useless wings to get up to altitude before launch thus requiring less propellant.
No, that doesn't work. The cheapest part of a spacecraft is its propellants, second cheapest is the propellant tanks, third cheapest is to buy or design a bigger engine at the start of the design process (kind of difficult later on in the development cycle). The most expensive part of a spacecraft is systems integration, and adding wings and horizontal flight is hard to integrate. The aerodynamics of ultra high speed wings is a huge pain, and simply isn't needed, so why bother.
You are probably not aware of the 666 rule... Not to keep you in suspense, mach 6 at 60,000 feet (thats 20 kilometers in the civilized world) is a whopping 6% of total orbital energy. An impossible speed at an impossible altitude provides practically no advantage over a simpler ballistic design with tanks that are about 1/20th bigger. Most people have the peculiar idea that a civilian airliner at cruise is "almost in orbit" and the slightest push is all that is needed for a 747 to reach the ISS, and that couldn't be further from the truth.
Making an airplane that flies at mach 6 and 60Kft is no laughing matter, and then making it also a spacecraft is simply unrealistic. On the other hand making the fuel tanks a bit larger is no big deal.
There are three advantages to air launch that apply in almost no situations. One is the obvious lack of ground support, don't need to license a "spaceport" just another airport, however the EPA, FAA, USAF, NORAD, BATF, etc are going to harass you just the same anyway so this is again another way to get a small advantage at a huge cost. I guess Rutan and friends thought it was worth it, but thats a regulation and political decision not a technological decision. The other advantage is for military purposes you can assume a large fleet of aircraft could simultaneously launch an even larger number of rocket vehicles from anywhere an airplane can fly, possibly at great surprise to the enemy, this is the nuclear tipped cruise missile idea applied to a suborbital ballistic trajectory, which isn't such a bad idea but never got much traction, at least in the USA. Maybe Rutan daydreamed of selling hundreds of his vehicles to the USAF for recon purposes or something. There is a third reason to airlaunch, if you're basically making a circus carnival ride as opposed to a real vehicle, then air launch makes the roller coaster ride even more spectacular.
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There also doesn't appear to be any redundancy, which has long been a design contention in the US and Russian schools of thoughts. I don't know where the ESA is, philosophically, on this issue.
This is easy: ESA has designed and is building and flying the most redundant and fault-tolerant unmanned spacecraft ever seen on this small planet: the ATV.
In an extreme case these things are able of successfully completing their missions with half of the solar panels and fuel tanks and 2/3 of everything else (including computers, antennas, sensors, fuel lines, thrusters, actuators, electrical lines, etc...) completely damaged. Of course this is theoretical, since they would abort the mission in these circumstances, to keep the ISS safe. But still as demonstrated by the first ATV, the Jules Verne, they can successfully complete a mission with any single failure in any subsystem except the main fuel tanks.
But, the absense of thrusters in the nose leaves few options if the brakes fail or are damaged.
Hmm... I'm not a rocket scientist, but you seem to know even less than me about this. Anyway this is only a technology demonstrator and one-time test.
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Since it's not reusable, the fragile heat resistant tiles are not a problem. The shroud is for aerodynamic control during launch, you can see in the video that the vehicle is a lifting body; have it sit exposed on top of the rocket would give you huge off-axis forces due to drag/lift.
Single stage to orbit doesn't make sense from a fuel economy point, you need a lot of big engine at the beginning, why accelerate all that mass into orbit? Ditto on reentry, you have to bleed off all that additional energy you put in, requiring lots more of those fragile heat shield tiles.
I'm aging rapidly, I bought a new game and had no idea if my machine was good for it.