*Since the space race first got started with Sputnik, we have been fascinated by the sky and space and what is beyond. For the last 50 years, the only way to get up into space was through government agencies, such as NASA. But today we are on the bleeding edge of being able to travel to space as a tourist.
While large-scale tourism is still at least a few years out, the advances that have been made would be mind blowing to the NASA scientists of the 1960s, especially for a commercial venture.
One of the biggest advances for the eventual success of commercial space programs has been all the information, technology and knowledge that has come before. Because companies like Virgin Galactic, SpaceX and XCOR Aerospace don’t have to develop everything from scratch, more elegant solutions to the major hurdles of space flight can be developed.
Material science has also been a huge contributor to making commercial spaceflight a possibility. Lighter, stronger materials mean that spacecraft are safer, and better manufacturing practices lead to more precise materials with better overall reliability. The computer models that are used to simulate aerodynamic capabilities or stresses the crafts can take have gotten better, which means that new ways of designing the crafts can be developed.
If getting up into space is hard, getting back down isn’t a whole lot easier. It takes a lot of energy to get into space; that energy translates into speed. The faster you’re going, the more energy you need to take out of the system to slow down for a safe landing.
The most rudimentary way is how the early space programs did it: have a sufficiently sturdy capsule that drops through the atmosphere with a parachute and lands in water. The space shuttle program was a step in the right direction since the shuttle could be reused and provided a less stressful reentry since the g-forces were lower at a more shallow angle of entry.
Virgin Galactic has developed a system with some of the advantages of both in its SpaceShipTwo system as seen in the VSS Unity. It is called the Feather System and it uses physics and aerodynamics to keep reentry at the correct angle. The Feather System works in the same sort of a manner that a birdie in badminton works; the feathers make sure the head always points in the direction of travel. Once enough energy has been bled off that gliding flight makes sense, the wings reposition themselves to give the pilot control over the direction the craft is heading for a landing similar to the space shuttle or a commercial airplane.
While there have been major advances, progress isn’t without cost. Going to space has always been a dangerous endeavor, even under the best of circumstances. The level of precision needed for much of the design, manufacturing and assembly is incredibly high, requiring many variables to be taken into account. When your aircraft is traveling close to or exceeding the speed of sound, any little thing that goes wrong can be devastating.
The Challenger disaster is a prime example of this. Because of colder-than-expected temperatures, an o-ring in the Challenger’s fuel system contracted beyond its specifications and caused the explosion just seconds after lift-off. Knowing the tolerance level of your materials is essential in an area of science and engineering that requires such precision. Better practices and the knowledge of what came before means that accidents like this should become more and more rare, hopefully to the point of being nearly impossible.