On Friday, Richard Branson unveiled Virgin Galactic’s newest rocket plane: SpaceShipTwo, called the VSS Unity.
Virgin Galactic is one of several companies that want to take humans to space. The flight plan is pretty dramatic: a large carrier aircraft called WhiteKnightTwo will carry Unity underneath, flying to an altitude of about 15,000 meters (50,000 feet). It releases Unity, which then ignites a rocket engine and thrusts upward to a height of more than 100 kilometers—the Kármán line, the accepted-upon but arbitrary altitude where space “begins”—with passengers experiencing several minutes of microgravity as it falls upward and then back down. It then glides back down to Earth like a plane.
To be clear, this is a suborbital flight, essentially up and back down. This takes far less energy and fuel than going into orbit, which requires speeds of 25,000 kph. But oh, what a trip! It's still a voyage to space, which is exciting, and I’ll note a lot of science can be done on such trips.
SpaceShipOne, the first generation Virgin Galactic rocket plane, was a test vehicle that won the X-Prize in 2006 for going into space, landing, then going back up again in less than a week. SpaceShipTwo is much larger, designed to carry two pilots and six passengers.
This is the second SpaceShipTwo vehicle. The first was successfully tested in 2013, but in 2014 suffered a catastrophic and fatal failure. During descent, the vehicle undergoes what’s called feathering, rotating the tail and wing assembly to provide more surface area and slow the craft. However, one of the pilots accidentally deployed the feathering mechanism prematurely, which broke the vehicle apart, killing both pilots.
Unity has been modified to prevent premature feathering. It will of course undergo extensive testing before powered flight; from what I can see Virgin Galactic has (wisely, in my opinion) not released an estimate of when that might be. Safety first. Incidentally, this is the first vehicle manufactured by the Spaceship Co., wholly owned by Virgin Galactic. The first two vehicles were built by Scaled Composites.
Suborbital flight tickets go for $250,000. That may sound like a lot, but there are plenty of people who can afford it (more than 600 people have bought tickets already). Also, that’s less than it would cost for a suborbital rocket flight for a scientific experiment, making this competitive on the university/government research level.
Private crewed spaceflight is on the verge of becoming a real factor in space exploration. SpaceX has already put uncrewed vehicles into orbit (and resupplied the space station) as has Orbital ATK. Blue Origin has had some successful flights of their New Shepard suborbital rocket, but as usual has not made public their future plans on when they will send up a crewed mission. Sierra Nevada recently received a NASA award for uncrewed resupply missions to the space station for their Dream Chaser spacecraft. Both SpaceX and Boeing have contracts with NASA to launch astronauts to the space station as well, and that may happen as soon as next year.
There have been setbacks, to be sure, but we live in exciting times. And proverbs be damned; exciting times are when I want to live.
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