Ares I-X

Ares IX was the name for the first test flight of an Ares rocket as part of the Constellation program, NASA. The main objective of the flight was the validation of the control software for Ares I, and the verification key of the missile flight characteristics, especially the first stage. In addition, the processes could be practiced and tested during assembly, launch preparation, recovery. The launch took place on 28 October 2009.

Construction of the rocket

Ares IX was a two-stage rocket with a height of 99.67 m and a launch mass of 816 t.

The first stage consisted of a derived from the Space Shuttle solid booster with four active segments and an inactive segment was provided by Alliant Techsystems and ( ATK ). The inactive segment included the first-stage flight computer which was developed by Jacobs Engineering and Lockheed Martin, and control of hydrazine -powered auxiliary power unit ( APU) for thrust vector control. Small extra solid motors controlled the separation process of the second stage. The auflackierte on the outside in black big Z was used for visual inspection of the rolling and tumbling motion of the rocket.

In the final version of the Ares I rocket five active elements (as opposed to four in the Space Shuttle ) will provide the necessary takeoff thrust.

The second stage was developed by the NASA Glenn Research Center and consisted of mass simulators for advanced level, service and command module. The upper level contained a further flight computer, which evaluated the data of the flight and sent to the ground station, and the system operated with nitrogen tetroxide and monomethyl Roll Control System ( RoCS ) by Teledyne Brown Engineering. It consisted of two small engines from the former Peacekeeper missile program, which nozzle tangentially arranged the rolling motion of the rocket at launch and during flight controlled by firing perpendicular to the longitudinal axis. Inside the upper dummy also adjustable steel plates were attached as ballast.

For the launch and flight control teams of the United Space Alliance, ATK and the Cape Canaveral Air Force Station were responsible.

Preparations

The preparations for the flight began with the preliminary deactivation of starting system 39B for Shuttle operations on January 1, 2007, so the launcher could be as far as possible modified for Ares I flights before the platform one last time for a possible shuttle flight (STS- 400) was used. Highbay 3 of the Vehicle Assembly Building has been modified and can build Ares I rocket. Only the Mobile Launch Platform 1 (MLP -1) was still occupied at that time by the Space Shuttle program.

The first component of the rocket, part of the solid boosters, met on November 10, 2008 at Kennedy Space Center. This was exactly like the booster of the shuttle brought by train to the Kennedy Space Center. Over the following weeks, additional components were delivered, including the simulators for the command module and the abort system, which arrived in late January. The final component arrived in late March. The parts were stored in the Vehicle Assembly Building to its mounting.

The Mobile Launch Platform 1 (MLP -1) was handed over on 25 February 2009 from the shuttle program and rolled to the launch 39B, so that the necessary modifications can be made. These mainly relate to the computers that monitor the systems of the shuttle on the platform. A few days later, it was rolled in the highbay 3, so that the mounting of the missile could begin. In early June, the starting system was fully transferred from the shuttle program.

On August 14, the assembly of the missile was completed and named October 31 as a scheduled start date. However, the start date was initially very uncertain, as the space shuttle Atlantis was already at this date on the adjacent launch pad 39A to withdraw later on mission STS -129 two weeks. Initially it was not clear whether a possible failure of the Ares IX rocket could affect the preparations at the Atlantis or even damage the shuttle. On September 22, the start date, due to the successful course of the preparations and countdown tests has been brought forward by three days on October 27. The rocket was moved to the launch pad October 20 and declared three days later during the flight readiness for acceptance fly.

Mission History

First start attempt

The first launch attempt was scheduled for 27 October 2009, but the rocket did not start. The main reason was the weather, which repeatedly crossed the rules laid down in the start limits during the entire four-hour launch window. Most problems experienced the rule over the allowable frictional charging. During the ascent of the rocket can cause static electricity on their surface, which may interrupt the communication with the ground stations. Since the Ares IX had as a new spacecraft no certificate against this danger, this criterion was so crucial. In addition arisen because of a cargo ship in the safety zone and because of a pitot tube cover that could only be resolved difficult, further delays. Overall, the launch was postponed for different intervals of ten times. One of the shifts was located just 2 minutes and 39 seconds before a possible start after the weather umschwang again after the restart of the four-minute Endcountdowns. It was decided shortly after the demolition of the countdown to the next day to make a new attempt.

Second start attempt of the flight

Due to the unstable weather conditions, the countdown had to be postponed several times for the second launch attempt on 28 October 2009, at 15:30 UTC until the rocket was successfully launched. It reached a maximum acceleration of just 2.5 g and a thrust of 11.6 MN a top speed of Mach 4.76 ( about 5800 km / h). Burnout of the first stage was after 123 seconds at about 40 km altitude it was separated. Independently drifted both stages due to the remaining kinetic energy at about 46 km altitude and then fell back towards the Atlantic Ocean. A little later the first stage parachute system was triggered in order to decelerate gradually. To reduce the opening shock, the main parachutes were first partially opened, with ripped at a more linen. Thus only two thirds of the braking action were present and thus were seen in the full open even on the second screen damage. This means that only about half of the full braking effect was obtained in the final stage, so that due to the higher speed on the water, a segment of the rocket casing was damaged on impact.

The second stage fell as planned uncontrollably in the Atlantic and was not recovered.

After the flight

Shortly after the flight, it was found that there has been damage to the lines for hypergolic fuels at the launch site. A seconded two hours after the splashdown to the launch special team later reported by substantial heat damage to the entire structure. Thus, both elevators were inoperable, the communication lines completely destroyed and some outdoor speakers melted beyond recognition, so interim solutions had to be used.

With the recovery of the first stage of the salvage divers discovered a kink in the missile casing, from which it concluded that the rocket auftraf with too high speed in an unfavorable angle to the water surface. Only one of the three 45 m measured parachutes had fully opened. The stage for further investigation met on 30 October in tow of the salvage ship Freedom Star again at the launch site.

Criticism

The relatively early test flight of Ares IX was heavily criticized from different sides. Since the rocket did not fly later with four booster segments and in use with five elements, the flight profile changed relatively strong. The first stage separation was carried out for example at Ares IX in 39.6 kilometers altitude instead of 57.1 km, as in later use flight. Thus some scientists fear that the data obtained will be worthless.

In addition, the software used conformed to the engine control is not the original, but was a modified version of the used on the Atlas V software. Also, the control thrusters did not correspond to the final version, on Ares IX control thrusters from Peacekeeper upper stages were used.

At times, it was feared that as another problem to strong vibrations towards the end of the thrust phase. This could pose a threat to the self-destruct system of the Ares IX, which could not possibly have by the vibrations can work. Therefore, it was feared at first that the mission could be granted not permitted.

However, NASA confirmed the usefulness of the flight. The early test flight was conducted, among others, in order to calibrate the computer programs used for the system design based on the measurement data. The findings will be incorporated in due time in the further development. The Commission of Experts appointed by President Obama to Norman Augustine supported the test flight. The Commission considered the flight even in the event of a stoppage of the Ares program or benefit.

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