ASTRONAUTS: WHY THE FUTURE MUST HAVE WINGS

**SPOILER ALERT** If you haven’t seen it yet, watch Astronauts:  Do You Have What It Takes?  Episode 4 on iPlayer first.

One of the tests that we were given was to present to the panel on a topic of space exploration.  Being an aerospace engineer my talk was on a topic that has fascinated me since childhood:  Access into Space.

Why The Future Must Have Wings

The hardest part of space travel in our near solar system is getting into space in the first place; out of our atmosphere. 

So far the only way we have reached orbital spaceflight is by rockets and these, on the whole, are inefficient, expensive and unreliable.

In comparison, aircraft are very efficient, reusable and for anyone who has flown half way across the world on holiday, incredibly affordable.

In order to understand the difference between these two technologies that have developed over a similar timeframe we really need to understand how a rocket engine works:

·       A rocket engine operates under the same principle of if release a blown up balloon.  By accelerating a large amount of gas out of the back, an equal and opposite force is imparted onto the rocket pushing it upwards, as described by Newton’s third law of motion.

·       The rocket is generating these hot, compressed gases internally through combustion.  For any combustion be it a rocket or a campfire, you need three things:  a fuel source, an oxygen source and a heat source.  The rocket carries all of these components on board with it in stored energy and as a result becomes extremely heavy.  This is evident when we see that the oxidiser is six times heavier than the fuel source!

·       But this does give it one big advantage, the rocket can operate in the vacuum of space but must result in expending it’s stages as it goes up to reduce mass.  And the atmosphere is just a hindrance.

In comparison, the airliner doesn’t see the atmosphere as a disadvantage but uses it beneficially in three different ways:

1.     The atmosphere provides the aerodynamic lift on the wings providing the upwards force opposing gravity.

2.     Instead of carrying the oxygen with it, the jet engine uses the oxygen in our atmosphere for combustion, and

3.     Crucially the jet engines use the air as the working fluid or propellant.  The big fans and compressors, suck the air in, compress it, heat it up in the combustion chamber and accelerate it out the back creating the equal and opposite force pushing the aircraft forward.

A much more elegant and efficient solution.  Clearly the future of space access must our atmosphere as a benefit rather than always seeing it as a hindrance.

That’s why there is a lot of interest in developing single-stage-to-orbit spaceplanes.

A spaceplane takes off and lands just like an aircraft and uses an air-breathing engine and wings to climb to the upper reaches of our atmosphere travelling at Mach 5, or five times the speed of sound.  As the air becomes too thin for the air-breathing engine, the intakes close off and it switches to a rocket engine, accelerating to Mach 25, for the last and final push into orbit.

Now imagine this, as our single stage to orbit vehicle hasn’t jettisoned it’s fuel tanks on its way to orbit, as soon as we reach orbit we have many more options open to us:  We can refuel the spaceplane with a conveniently placed orbital refuelling station giving it enough fuel to gently pop over to the moon for a supply trip or a tourism visit and after a few days it will coast back to Earth and re-enter the Earth’s atmosphere.  But the benefits don't just stop there, with the much superior re-entry characteristics the spaceplane offers it can land on one of several runways around the world and after a quick check over, a refuel, it is ready to go again.  Completely reusable.

And that is why the future must have wings.

Astronauts:  Do You Have What It Takes?  Episode 5 is on Sunday 24th September at 8pm BBC2.

ASTRONAUTS: DOCKING ONTO THE INTERNATIONAL SPACE STATION

**SPOILER ALERT** If you haven’t seen it yet, watch Astronauts:  Do You Have What It Takes?  Episode 3 on iPlayer first.

I remember a time when I was seven or eight and my brother nine or ten years old and we used to walk 400m away to a Scouts friend’s house to play on his computer console.  He had a Nintendo Entertainment System and we used to marvel at how he used to navigate the two dimensional terrain of Mario Brothers and save Princess Peach with so much more finesse and speed than we could muster.  We begged our parents to buy us one but finances and ideology left us disappointed.  So the only times we got to play in these pixelated virtual worlds was at friends’ houses or when we were older, at the local video rental store that had an arcade:  In the evenings and especially after the hour of prayer at the local mosque teenage boys crowded around the arcade waiting their turn on Street Fighter II.  It was the ultimate fighting game, requiring unbelievable speed and muscle memory to enact the combination of moves required to beat your opponent.  All I could do was stand on tiptoes trying to get a view and not be pushed out by the older kids.  The few times that I did manage to get to the front and challenge the winner, my 20p was wasted in a matter of seconds.

What’s all of this got to do with the astronaut selection?  The answer is that I wish I had played a few more video games and the reason for this will become apparent a little later on.

It’s now episode 3, and the tests are becoming more difficult.  I couldn't imagine a more nerve wracking test.  A three-time astronaut and former commander of the International Space Station (ISS) sitting next to you, telling you that within ten minutes you have to dock the Soyuz capsule onto the ISS.  It was a dream come true and I was in awe of what we were asked to do.

Both the Soyuz and the ISS are pinnacles of human endeavours in space.  The ISS is the multi-billion pound product of an incredible collaboration between fifteen countries and has been permanently inhabited since the year 2000.  It is the largest space structure ever built and can easily be seen with the naked eye (there is an app for that) zooming across the night sky.  It orbits Earth every 90 minutes making the inhabitants of the ISS the fastest humans in the world. 

The Russian Soyuz is the most successful human transportation space vehicle ever created and since 2011 when the Space Shuttle retired it is the only crew transportation vehicle to the ISS.  Devised in the 1960s and still flying today it has the longest operational history of any spacecraft and the safest.  There is a Soyuz spacecraft permanently docked to the ISS at all times, serving as an emergency lift raft and if you see any cosmonauts or astronauts arriving or leaving the ISS it would be via a Soyuz.

Thus, docking a Soyuz onto the ISS is one of the most important training tasks an astronaut must become competent at.  Failure to dock would mean that crucial supplies and a changeover of astronauts would not be able to happen.  But that is not as bad as crashing into the ISS, as Chris Hadfield had put it, going too fast at docking could cause a rupture of the ISS killing everyone on board.  But it doesn’t end just there, if the ISS breaks up upon a crash, a cascading amount of orbital debris travelling at 17,000mph could end up making that orbit completely unpassable. 

Hence the deer in the headlights moment.

The German Aerospace Center in Cologne, Germany where the simulator was located is also where the European Astronauts Corp is located (right across the road).  Both Chris Hadfield and Tim Peake have trained there, in fact Tim’s name was still on one of the rooms we were using.  The simulator was the same as that which the astronauts train on and is a replica of the actual Soyuz spacecraft controls.

To dock successfully not only did we have to manoeuvre the Soyuz to the right spot in all three spatial dimensions but also be travelling at the right speed.  Too slow and you’d bounce off, too fast, well, you would crash.  It required a good level of spatial awareness, good hand eye coordination, speed and nerve.  I was so close to docking, but my crosses were ever so slightly misaligned and so I backed up and the time ran out.

Interestingly, those that did well at this test were either a pilot or gamers. After this test and the Mars rover test I wish I had played more computer games.  The right sort of games can help develop your 3D spatial awareness, memory and hand eye coordination.  The right sort of game can help with strategy and tactics.  Computer games are not just devilish past times that would lead to a lifetime of underachievement as I was brought up to believe but offer valuable skill sets that are becoming increasingly important.  We are living in a technological revolution where human-machine interfaces are becoming commonplace and developing those skill sets are becoming important not just for astronauts but for all manner of jobs:  Airline pilots can become qualified on a simulator alone, surgeons will soon be controlling small operating machines, drone camera operators are already in high demand.

Astronauts:  Do You Have What It Takes?  Episode 4 is on Sunday 10th September at 8pm BBC2.