Yesterday saw the successful and historic launch of the SpaceX Falcon 9 rocket boosting the Dragon cargo capsule into orbit. After orbiting the Earth and performing several manoeuvring tests the Dragon capsule executed a de-orbit burn and successfully re-entered the atmosphere and splashed down into the Pacific Ocean. The whole flight from launch to splashdown took just under 3 hours 20 minutes.
This was an incredible mission which managed to perform 100% of it’s milestones and targets, despite an expectation of 60-70% prior to launch. There were a number of firsts on this launch, the most notable was the fact that this was the first (Commercial Orbital Transport Services) COTS mission, and the first commercial spacecraft to re-enter Earth’s atmosphere and land.
Youtube: Our launch day video
The main success of this flight is the fact that with the retirement of the Space Shuttle there is a redundant continuation capability to re-supply the International Space Station. There is now proof that the Commercial Crew and Cargo Program is viable and that the future of Space Exploration can be successfully pioneered as joint public commercial projects.
There were three opportunities to launch yesterday between 9:00 and 12:22. These were “windows” of about 6 minutes when all the tracking and range monitoring equipment was precisely aligned to support the mission. SpaceX decided to shoot for the back end of the first window at 9:06. At T-10 minutes the terminal countdown was entered and everything was green across the board. The countdown continued until T-2:48 when suddenly we heard over the feed that there was an abort.
The abort immediately halted the countdown and the process of safing the rocket and determining the cause of the abort started. Before we knew what the exact problem was SpaceX decided to target the next window at 10:43 for the next attempt and reset the countdown clock to T-13 minutes.
The abort was caused by a false Orbital Interrupter alert. The Orbital Interrupter is part of the Flight Termination System which is designed to destroy the spaceship in cases of extreme malfunction. Obviously the FTS is a critical component to any space flight, but most particularly important for test flights.
Having determined the cause of the abort the launch sequence came out of the hold and the countdown resumed at 10:30 EDT. This time the countdown preceded all the way. The first thing we saw when the rocket engines lit was a huge plume of exhaust shooting out of the flame trench. As the engines ramped up to full power the rocket was held in place by the Hold-Down arms until the rocket was released and started to climb towards the sky.
As the Falcon 9 started to rise the umbilical connections on the strong-back pulled away. This caused the fuel in the service pipes to ignite and combine with the flame issuing from the nozzles at the base of the rocket. A few seconds later the Falcon 9 and Dragon had cleared the string-back and the lightning protection and was hurtling towards space.
Three minutes later the first stage had completed its task. The fuel burnt up and the rocket engines were shut down. The booster was then separated from the rest of the rocket and the second stage engine was lit. About a minute later the nose cone of the Dragon capsule was jettisoned. This was accompanied by cheers on the launch control audio channel. A further five minutes into the flight and the second stage had lifted the Dragon capsule into orbit.
When the second stage shut down and separated from the Dragon the Falcon 9 had done its job. The Dragon capsule was now in orbit around the Earth. The flight plan called for a 300Km near-circular orbit with an inclination of 34.5 degrees. The orbit achieved was reported by SpaceX as between 288Km and 301Km with an inclination of 34.53 degrees, with allowable tolerances.
After orbit was achieved there was little information released from SpaceX regarding the manoeuvres and test being executed on the Dragon capsule. Shortly after 1:15pm EST the Dragon capsule began its re-entry into the atmosphere by initiating a de-orbit burn using 4 of the 18 Draco manoeuvring thrusters. This was completed about 5 minutes later and the capsule was on its way back home.
On its way through the atmosphere the base of the capsule was expected to experience temperatures in excess of 1600 centigrade. To disperse this heat SpaceX protect the main capsule with PICA-X. PICA-X is a new SpaceX material derived from the NASA developed PICA (Phenolic Impregnated Carbon Ablator). To slow the capsule down to a speed that allows a soft(ish) landing the Dragon has a series of parachutes. The first drone chutes opening at 45,000ft started the deceleration process, and then were replaced by three 116ft main parachutes at around 10,000ft. These slowed the Dragon down to a speed where a “soft splashdown” marked the end of the flight.
The mission was deemed to be a 100% success bucking the statistical trend for second test flight failures. Everything in the mission was nominal with a splash down within 800m (1/2 mile) of the target site.
Elon Musk CEO and CTO of SpaceX normally an eloquent orator was lost for words in the post mission press conference claiming “I’m in semi-shock. I wish I could be more articulate at times like this… …There is a natural reaction that just blows my mind.” Elon was very mindful of the contribution of previous space exploration and technologies developed by NASA. He said “We are only here because we stand on the shoulders of Giants”.
Despite the accolades piled on the NASA and the other supporting agencies the SpaceX story is one of childhood dreams. SpaceX was formed just 8 years ago in 2002 and developed the first private liquid fuelled rocket to achieve orbit. In 2008 SpaceX was awarded the COTS contract by NASA. Since then they have developed, and now proved the Falcon 9 as a platform to deliver payloads into orbit and, with this mission, proved they have an operable cargo delivery system to the ISS. This has to be an incredible achievement by any standards.