Europe needs independent manned access to space via its own spacecraft. The current situation where we - the world's largest economy - have to beg other nations to please give our astronauts a lift is ridiculous and untenable.

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Right, so let's see what it would take to develop a European spaceship. It would obviously be based on existing technology, mainly the ATV freighter and its launcher, a version of the European heavy lifter Ariane 5 ES.

We can re-use the ATV's service module, including tanks, propulsion, attitude control and power supply, and we can use the air lock and the rendezvous and docking support systems.  

Use of the Ariane 5 ES, which will be used for ATV and Galileo navigation satellite launches, imposes a mass limit for the manned spaceship of around 20 metric tons.  This compares to around 7 tons for the Russian Soyuz TMA, more than 9 tons for the SpaceX Dragon and up to 25 tons for the new NASA spaceship Orion from the constellation project.

It is a little-known fact (but nevertheless a fact) that using the Ariane 5 from its launch base in Kourou also pretty much fixes the target orbit. Ariane 5 can only be launched into few, narrow azimuth ranges (claims to the contrary notwithstanding):

• Due East: then the expended  cryogenic core stage EPC will fall into the Southern Atlantic in that kink between Western and Southern Africa. This corresponds to an orbit inclination of about 6-7 degrees.
• North by North-East, as for the ATV launch, then the EPS will fall into the Northern Atlantic off Spain. The orbit reached then has an inclination of about 52 degrees, nicely matching that of the ISS. 

Forget "in between" inclinations, e.g., around 30 degrees -  this would require a launch into an ENE azimuth and lead to an EPC impact over Western Africa. Conversely, for an ESE launch, the ascent trajectory would lead over the South American land mass, also a major no-no. One could of course launch due East and then turn south with a "dog-leg"-manoeuvre, but this entails a massive payload penalty. We can safely assume that manned ships will go to 51.6 degrees of inclination, certainly as long as the ISS is there, but likely also after that, at least until the Kourou spaceport remains in use.

So much on the orbit.

What would a European spaceship look like? Basically, there are two concepts to choose from:

1. A capsule design that thumps down with quite a bump (the technical term for that is "vertical semi-hard landing")
2. A winged glider that lands horizontally on a runway like a plane.

A winged glider has the advantage of being sexy. It's way cool. It has "future" and "progress" written all over it. This is what you expect a spaceship to look like. No capsule can beat this: look at one of those and you start wondering whether you've been time-warped back to the sixties.

The capsule-based system comes out a clear winner in all other respects. First and foremost: It's safe. With a capsule, you can save the crew during any phase of the - always inherently dangerous - launch, even if the rocket doesn't even make it off the pad or suffers an explosion or serious malfunction in mid-air (see here and here). Furthermore, the capsule's heat shield, which is simple and therefore robust, is protected all the way through the mission until you need it for reentry. Nothing can hit and damage it. A capsule can be design to be "ride" the hypersonic flow in a stable attitude, just by choosing its shape and mass distribution appropriately. Re-entering capsules have demonstrated their ability to recover from major malfunctions, such as  entering the atmosphere upside-down.

Contrast this with the winged glider. Either it's attached to the side of the rocket, putting it and its crew right into harm's way in the case of an explosion (see here). Or it's on top of the stack and the aerodynamic forces on its wings during the various regimes of ascent make control of the rocket a nightmare. If things go badly wrong, mostly, there is no way to save the crew. The vehicle's belly and wings carry the heat shield. This has a complex shape with small curvature radii and therefore tremendous temperature gradients. It is highly susceptible to damage, but it has to be exposed to any object that might (and likely will) damage it (see here).

If the glider doesn't enter at exactly the required attitude, or if it doesn't follow exactly the required pattern of manoeuvres during the descent from over Mach 20 down to touchdown speed, it's curtains. And even if the re-entry works fine and due to some problem the runway is missed, you might still lose ship and crew.  

I don't see any choice here. Forget the winged glider. The only acceptable design for a manned spaceship is:  

A modular system comprised of a service module carrying a pressurised capsule. The capsule is shaped like a blunt cone with the heat shield at the bottom end. We already have the service module but still need to develop the capsule.

Of course even with a capsule, we wouldn't have a fully fledged manned transportation system yet. But we'd have at least one half of a transportation system, one that would be capable of manned transfer flights in space and manned return to the surface. 

This would already constitute a major step forward. It would enable Europe to provide a lifeboat for the ISS, requiring only fairly minimal development effort.

Currently, the lifeboat function is provided solely by the Russian Soyuz TMA craft. This can transport 3 people back to the Earth, but no cargo.   

A European counterpart to the Soyuz TMA would be very useful. With this spacecraft, the Europeans could gain extensive experience with manned in-orbit-operations and manned reentry while developing the infrastructure for manned launches. Firstly, the rocket has to be man-rated, i.e., rendered appropriate for manned launches. "Man-rating" is a somewhat vague term; it means that even a catastrophic malfunction must leave some time for an adequate reaction.  

Mostly, the reaction will consist in one thing: Pyro bolts between service module and capsule fire, separating the capsule from the remainder of the stack. Simultaneously, an escape system ignites. This is a powerful solid rocket mounted atop the capsule that rapidly pulls the capsule away from the huge fireball into which the rocket is transforming itself.  

The spent escape system then jettisoned, which re-orients and, having braked to a safe airspeed, deploys the chutes. The escape system must have lifted the capsule to the minimum altitude required for the chutes to work.

Major development effort is required here; this is the expensive part. Designing the capsule first and the launch system later spreads the cost over a longer period, but at some point, the investment is required, even if not all in one go.

The figures I have heard and read concerning the cost of the development of a European manned transportation system along the lines of what I have described above are around 5 billion Euros, i.e., around 2 annual ESA budgets. I am not stating this figure because I think it is staggering or excessive - it is about in line with the projected cost for the European navigation system Galileo or with other large infrastructure and technology projects.

That is what such things cost to develop - and incidentally, the sum is all spent here on Earth, in form of research and development, so every Euro is well-invested. There is no point in kidding ourselves that we can obtain world-class cutting-edge technology without heavy investments. Other nations do not harbor such illusions; they are willing to invest in their future. Either we want to take the technological lead, then we should be prepared to shoulder the cost. Or we give wanting to play in the premier league, but then we should also accept the drawbacks of being technologically outclassed by others.

I'd say that there isn't much of a choice here, either. Space research is a key technology, and it has a high visibility. The development of manned transfer capabilities should be started without delay, led by ESA, and this will require a significant and sustained rise in the European space budget.  

The alternative is to stay put and watch as the rest of the world leaves us behind.

Annex

The Ariane 5 ES - ATV Ascent Trajectory 

The spent solid boosters fall into the Caribbean, the spent cryogenic stage EPC drops into the Atlantic ocean off the Spanish coast. At this time the rocket sill is on a sub-orbital trajectory. After separating from the EPC the upper stage EPS fires immediately and raises the apogee of the orbit to around 250 km. When reaching the apogee, the upper stage fires again and inserts the payload (the ATV, but the procedure will be similar for a manned craft) into a circular orbit. The payload uses its onboard propulsion system to reach the ISS orbit, again some 100 km higher. The spent EPS fires some last manoeuvres to de-orbit itself; it crashes into the Pacific ocean.

ATV-Evolution

There exist plans at ESA and industry for the development of a version with a pressurised capsule based on ATV technology. For further information, go here.

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