Ares 1

Ares I was the crew launch vehicle that was being developed by NASA as part of the Constellation program. The name "Ares" refers to the Greek deity Ares, who is identified with the Roman god Mars. Ares I was originally known as the "Crew Launch Vehicle" (CLV).

NASA planned to use Ares I to launch Orion, the spacecraft intended for NASA human spaceflight missions after the Space Shuttle was retired in 2011. Ares I was to complement the larger, uncrewed Ares V, which was the cargo launch vehicle for Constellation. NASA selected the Ares designs for their anticipated overall safety, reliability and cost-effectiveness. However, the Constellation program, including Ares I was cancelled by U.S. president Barack Obama in October 2010 with the passage of his 2010 NASA authorization bill. In September 2011, NASA detailed the Space Launch System as its new vehicle for human exploration beyond Earth's orbit.

In January 2008, NASA Watch revealed that the first stage solid rocket of the Ares I could have created high vibrations during the first few minutes of ascent. The vibrations would have been caused by thrust oscillations inside the first stage.[26] NASA officials had identified the potential problem at the Ares I system design review in late October 2007, stating in a press release that it wanted to solve it by March 2008.[27] NASA admitted that this problem was very severe, rating it four out of five on a risk scale, but the agency was very confident in solving it.[26] The mitigation approach developed by the Ares engineering team included active and passive vibration damping, adding an active tuned-mass absorber and a passive "compliance structure" – essentially a spring-loaded ring that would have detuned the Ares I stack.[28] NASA also pointed out that, since this would have been a new launch system, like the Apollo or Space Shuttle systems, it was normal for such problems to arise during the development stage.[29] According to NASA, analysis of the data and telemetry from the Ares I-X flight showed that vibrations from thrust oscillation were within the normal range for a Space Shuttle flight.[30]

A study released in July 2009 by the 45th Space Wing of the US Air Force concluded that an abort 30–60 seconds after launch would have a ~100% chance of killing all crew, due to the capsule being engulfed until ground impact by a cloud of 4,000 °F (2,200 °C) solid propellant fragments, which would melt the capsule's nylon parachute material. NASA's study showed the crew capsule would have flown beyond the more severe danger.[31][32]

Ares I-X launches from Kennedy Space Center launch pad 39B on October 28, 2009.
The Ares I igniter was an advanced version of the flight-proven igniter used on the Space Shuttle's solid rocket boosters. It was approximately 18 inches (46 cm) in diameter and 36 inches (91 cm) long, and took advantage of upgraded insulation materials that had improved thermal properties to protect the igniter's case from the burning solid propellant.[33] NASA successfully completed test firing of the igniter for the Ares I engines on March 10, 2009 at ATK Launch Systems test facilities near Promontory, Utah. The igniter test generated a flame 200 feet (60 meters) in length, and preliminary data showed the igniter performed as planned.[33]

Development of the Ares I propulsion elements continued to make strong progress. On September 10, 2009, the first Ares I development motor (DM-1) was successfully tested in a full-scale, full-duration test firing.[34] This test was followed by two more development motor tests, DM-2 on August 31, 2010 and DM-3 on September 8, 2011. For DM-2 the motor was cooled to a core temperature of 40 degrees Fahrenheit (4 degrees Celsius), and for DM-3 it was heated to above 90 degrees Fahrenheit (32 degrees Celsius). In addition to other objectives, these two tests validated Ares motor performance at extreme temperatures.[35][36] NASA conducted a successful 500-second test firing of the J-2X rocket engine at John C. Stennis Space Center in November 2011.[37]

The Ares I prototype, Ares I-X, successfully completed a test launch on October 28, 2009. Launch Pad 39B was damaged more than with a Space Shuttle launch. During descent, one of the three parachutes of the Ares I-X's first stage failed to open, and another opened only partially, causing the booster to splash down harder and suffer structural damage. The launch accomplished all primary test objectives.