Tags

, , , , ,

The era of mass space tourism is about to begin.  Virgin Galactic’s SpaceShipTwo is about to launch. It is based upon SpaceShipOne, which was an experimental spacecraft which won a $10 million dollar prize for being the first privately built spacecraft to travel to an altitude of 100 km.  This, as you may remember from my previous post, is the point at which space begins, according to the Fédération Aéronautique Internationale.

What will the experience be like?

Passengers will board SpaceShipTwo at the purpose-built Spaceport America in New Mexico. SpaceShipTwo will be attached to a rather strange looking twin hulled carrier aeroplane called WhiteKnightTwo.

White Knight Two

Twin hulled WhiteKnightTwo on a test flight  – Image provided by Craig Boy. in a real flight SpaceShipTwo would sit between the two hulls. 

After take off, WhiteKnightTwo, will steadily climb to an altitude of 51,000 feet (15.5 km). This is about 50% higher than the typical height which a commercial aeroplane reaches on a long flight. From this altitude passengers will notice that the sky overhead will be dark blue because there is so little atmosphere above them. Also, because they are so high up, they will be able to see significantly further than they can on a normal jet flight, a distance of around 440 km to the horizon.

When it has safely reached 15.5km SpaceShipTwo will separate from WhiteKnight Two, and its rocket motor will then ignite.

Awaiting Image 

SpaceShipTwo Accelerating into Space

When this happens, the passengers will immediately feel a very strong acceleration, or g-force, which will pin them back into their seats. The force will be around 3-g meaning that a human would, while the rocket motor is firing, weigh three times a much as they do on earth, making it a great effort to move any part of their body. After only 70 seconds SpaceShipTwo will be travelling at 2,500 mph (4000 km/h). The rocket motor will then cut out and the passengers will suddenly go from being pinned to their seat by the strong g-force to being completely weightless.

 

They will be able to get out of their seats, float around the cabin, look out of the windows and take in the view. The spacecraft will continue to coast upwards, being slowed all the time by the Earth’s gravity. After a further two minutes it will cross the 100 km boundary into space. Its peak altitude will be around 110 km. If the passengers look outside the window at this point they will notice that the sky will be black even though the sun is shining. This is because there is so little atmosphere above them. They will be able to see about 1200 km to the horizon, so if it were flying over London passengers would be able to see the Orkney Islands, off the North cost of Scotland, out of the window on one side and Barcelona, in Northern Spain, on the other side. This particular scenario, however, is a very long way in the future, as of course the flights will be over New Mexico.

After it reaches peak altitude the spacecraft will start falling back to Earth.  Initially it will be in free fall but as it gets lower and lower and encounters traces of the Earth’s atmosphere, it will start to experience what is called ‘drag’, or friction, which will reduce the acceleration. The wings of the spacecraft, which are hinged, will tilt upwards, thus further increasing the drag and slowing the spacecraft down. The passengers will no longer be weightless but will be subject to a gradually increasing g-force. When the spacecraft descends to an altitude of 15 km, the wings will tilt back to their normal position, which will make it more streamlined, reducing the drag. The spacecraft will continue to gradually descend, gliding back to land on a runway.

Awaiting Approval to use Image 

SpaceShipTwo Landing

The whole experience from when SpaceShipTwo takes off, attached to WhiteKnightTwo, to landing on the runway will last around three hours. The passengers will be weightless for around five minutes and will spend roughly two minutes in space.

When will SpaceShipTwo take space tourists into space ?

No date has been set for the first commercial flight.  At the moment SpaceShipTwo has completed three test flights with a peak altitude of around 22 km. To get a US Federal Aviation Administration licence to carry passengers above the 100 km line, it will need to have several test flights reaching its full speed and going above 100 km in altitude. Although Richard Branson, chairman of the Virgin group, said back in February that the first commercial flight would be later in 2014, I think that the probability of that happening is extremely small. It is much more likely to be in 2015 or 2016.

How much will it cost?

On their website, http://www.virgingalactic.com, Virigin Galactic quote a price of $250,000. Passengers must also be in reasonable health and fit enough to withstand the g-forces during the rapid acceleration. There are already over 600 confirmed bookings, each of whom have paid a $20,000 deposit – Brad Pitt, Angelina Jolie and Katy Perry are among them.

I’m sure most of you will agree that this is a sky-high price tag for a three hour experience, even for the very rich. For a quarter of that cost you could travel around the world for 112 days and nights on the cruise ship Queen Mary 2, staying in the most luxurious cabin – with your very own private butler.

One reason why the price is so high is that Virgin Galactic need to recover their development costs of around $500,000,000. It is also a matter of supply and demand – the fact is that there are passengers able and willing to pay this amount, and initially Virgin Galactic will be the only company offering this service.  They eventually plan to have a fleet of five SpaceShipTwos, each of which will fly twice a day. When this happens – and as other companies enter the market – it is likely than the price will come down significantly. If Virgin Galactic were to charge $25,000 per ticket and to fly twice a day, 300 days a year, carrying six passengers, this would still generate $450,000,000 in revenue. At this price a whole new market could open up and it might appeal to people of more limited means as the experience of a lifetime.

Awaiting Image 

British Business woman Marsha Waters with Richard Branson when she became Virgin Galactic’s  600-th customer in 2013.

How Safe is it ?

Going into space is a risky business, and the technology behind SpaceShipTwo is unproven. The Space Shuttle flew 135 missions between 1981 and its retirement in 2011, and two of those mission ended in failure – with the death of all of the crew. The chances of a shuttle astronaut being killed on a space flight was therefore around 1 in 67. Until the technology becomes more established it is impossible to say what the risks of flying in SpaceShipTwo will be. However they will undoubtedly be far higher than travelling in a commercial jet airliner, where the risks of dying on an individual flight are around 1 in 10 million. As a vote of confidence in the safety of SpaceShipTwo, Richard Branson has said on many occasions that he and his family will fly on the first commercial flight.

Next Post 

SpaceShipTwo offers tourists a short hop just across the boundary of space for a few minutes. In my next post I will discuss in more detail the future of space tourism into orbit and beyond.

Advertisements