Virgin Orbit
On Sunday afternoon, Virgin Orbit joined the rare club of companies that developed a rocket privately and successfully launched it into orbit. In addition, with its LauncherOne rocket launched from a 747 aircraft, the California-based company became the first to reach orbit with a liquid fuel rocket launched into the air.
“This magnificent flight is the culmination of many years of hard work and will also spark a new generation of innovators on the way to orbit,” said Sir Richard Branson, the company’s founder. “Virgin Orbit achieved something that many considered impossible.”
Sunday’s flight, which included multiple shots from the LauncherOne’s top-stage engine and successful deployment of several small satellites for NASA, culminates in a development program spanning about eight years and a myriad of technical challenges.
A rocket launched from the air has some advantages over traditional propellants launched from the ground, most notably flexibility in reaching different orbits and the ability to take off in very inclement weather. However, to obtain these benefits, Virgin Orbit had to design a liquid fuel rocket that could be launched horizontally from an aircraft, ignite its engines and quickly orient itself in a more vertical trajectory. (Although Orbital Sciences developed the Pegasus rocket to be launched from an aircraft carrier in the late 1980s, it was a simpler project using solid propellant.)
A rocket launched from an aircraft cannot start its engines immediately due to the proximity of the plane and its pilots. In the case of LauncherOne, the NewtonThree engine of the rocket is switched on 3.25 seconds after being dropped. The main engine starts in 5.2 seconds. During that time, the rocket is falling and losing the speed it gained from the aircraft at about 30,000 feet.
Technical challenges
Due to this drag, a negative acceleration acts on the booster, causing all kinds of problems for both the rocket structure and its propulsion system. One problem is that this starts to force liquid oxygen and kerosene propellants to the top of the tanks and the expansion gas – which fills the tanks as the propellant is spent – towards the engine inlet.
The ignition process itself is also a challenge in the air. On the ground, a rocket usually starts its engines, and the on-board computer performs a final, quick check to make sure everything is in good condition, before the rocket is launched. That’s why takeoff usually follows ignition for a few seconds. There is no room for error with Launcher One, because if the ignition doesn’t happen, the rocket simply falls into the ocean.
Image showing the ignition of LauncherOne after being knocked over by your Cosmic girl aircraft.
Virgin Orbit
The company and its engineers were able to overcome all of these problems and more with the design of their rocket. But it took time and a lot of money. Branson acknowledged that he and other investors put about $ 1 billion into Virgin Orbit, which is a lot of money to invest in a small satellite launcher, however innovative. Ars explored Virgin Orbit’s path to profitability last year, and the path will not be easy.
But those are discussions for another day. On Sunday, Virgin Orbit reached orbit only on its second flight, with what appeared to be a virtually flawed mission. Few companies have done this with privately developed vehicles – very few besides Orbital Sciences, SpaceX and Rocket Lab. It was a good day.