Jump to content

Ares I

From Wikipedia, the free encyclopedia

This is an old revision of this page, as edited by Vincecate (talk | contribs) at 09:33, 22 August 2009 (→Analysis and testing). The present address (URL) is a permanent link to this revision, which may differ significantly from the current revision.

This article is about the Ares I launch vehicle. For other uses, see Ares (disambiguation).
Ares I
Artist's impression of Ares I launch
Functionman-rated orbital launch vehicle
ManufacturerAlliant Techsystems (Stage I)
Boeing (Stage II)
Country of originUnited States
Size
Height94 metres (308 ft)
Diameter5.5 metres (18 ft)
MassTBC
Stages2
Capacity
Payload to LEO
Mass25,000 kg (55,000 lb)
Launch history
StatusIn Development
Launch sitesKennedy Space Center, LC-39B
Total launches0
First flightScheduled for 2014 (Augustine Commission estimates 2017)
First stage
Powered by1 Solid
Maximum thrustTBC
Burn time~150 seconds
PropellantSolid
Second stage
Powered by1 J-2X
Maximum thrust1,308 kilonewtons (294,000 lbf)
Burn timeTBC
PropellantLH2/LOX
[edit on Wikidata]

Ares I is the crew launch vehicle being developed by NASA as a component of Constellation Program.[1] The name "Ares" refers to the Greek deity Ares, who is identified with the Roman god Mars.[2] Ares I was originally known as the "Crew Launch Vehicle" (CLV).[3]

NASA plans to use Ares I to launch Orion, the spacecraft being designed for NASA human spaceflight missions after the Space Shuttle is retired in 2010. Ares I is intended to complement the larger, unmanned Ares V, which is the cargo launch vehicle for Constellation. The Ares designs were selected for their anticipated overall safety, reliability and cost-effectiveness.[4]

Development

Advanced Transportation System Studies

In 1995 Lockheed Martin produced an Advanced Transportation System Studies (ATSS) report for the Marshall Space Flight Center. The executive summary for the ATSS report describes several possible vehicles much like the Ares I design, with liquid rocket second stages stacked above segmented SRB first stages.[5] The variants that were considered included both J-2S and SSME engines for the second stage.

Exploration Systems Architecture Study

On April 29, 2005, after President Bush had announced the Vision for Space Exploration in January 2004, NASA chartered the Exploration Systems Architecture Study to accomplish specific goals:[6]

  • determine the "top-level requirements and configurations for crew and cargo launch systems to support the lunar and Mars exploration programs"
  • assess the "CEV requirements and plans to enable the CEV to provide crew transport to the ISS"
  • "develop a reference lunar exploration architecture concept to support sustained human and robotic lunar exploration operations"
  • "identify key technologies required to enable and significantly enhance these reference exploration systems"

A Shuttle-derived launch architecture was selected by NASA for the Ares I. Originally, the vehicle would have used a four-segment solid rocket booster (SRB) for the first stage, and a simplified space shuttle main engine (SSME) for the second stage. An unmanned version was to use the five-segment booster, but with the second stage using the single SSME.[7] Shortly after the initial design was approved, additional tests revealed that the Orion spacecraft would be too heavy for the four-segment booster to lift,[8] and in January 2006 NASA announced they would slightly reduce the size of the Orion spacecraft, add a fifth segment to the solid-rocket first stage, and replace the single SSME with the Apollo-derived J-2X motor.[9] While the change from a four-segment first stage to a five-segment version would allow NASA to construct virtually identical motors (albeit with some interchangeable segments), the main reason for the change to the five-segment booster was the move to the J-2X.[10]

Comparison of the basic size and shape of the Saturn V, Space Shuttle, Ares I, Ares IV, and Ares V

The Exploration Systems Architecture Study concluded that the cost and safety of the Ares was superior to that of either of the Evolved Expendable Launch Vehicle (EELVs). However the cost estimates in the study were based on the assumption that the EELVs would have to be launched from the Shuttle pad at Launch Complex 39, and that the Vehicle Assembly Building, Mobile Launcher Platforms, and LC-39 would have to be modified for the EELVs.[citation needed] However facilities already exist for servicing and launching the EELVs at LC-37 (Delta IV) and LC-41 (Atlas V), which could be modified to accommodate crew boarding and would not have interfered with Shuttle operations. The ESAS launch safety estimates for the Ares were based on the Space Shuttle, despite major differences, but included only launches after Challenger, and counted each of the remaining launches as two safe launches of the Ares booster. The safety of the Atlas V and Delta IV was estimated from the failure rates of all Delta II, Atlas-Centaur, and Titan launches since 1992, although they are not similar designs. This meant, for example, that the relatively high failure rate of the Titan IV, which used strap-on solid rocket motors, did not count against the Ares, which has a main solid rocket motor, but counted against the Delta IV Heavy, which has only liquid propulsion.[citation needed] In May 2009 the previously withheld appendices to the 2006 ESAS study were leaked, revealing a number of apparent flaws in the study, which gave safety exemptions to the selected Ares I design while using a faulty model which unfairly penalized the EELV-based designs.[11][unreliable source?][12][unreliable source?]

Contractor selection

NASA selected Alliant Techsystems, the builder of the Space Shuttle Solid Rocket Boosters, as the prime contractor for the Ares I first stage.[13][14] NASA announced that Rocketdyne will be the main subcontractor for the J-2X rocket engine on July 16, 2007.[15] NASA selected Boeing to provide and install the avionics for the Ares I rocket on December 12, 2007.[16]

On 28 August 2007 NASA awarded the Ares I Upper Stage manufacturing contract to Boeing. Boeing built the S-IC stage of the Saturn V rocket at Michoud in the 1960s. The upper stage of Ares I is to be built at the NASA Michoud Assembly Facility, which is where the Space Shuttle's External Tank is currently constructed, and the former construction site of the Saturn V's first stage, the S-IC. [17][18]

J-2X engines

Main article: J-2X (rocket engine)

At approximately US$20-25 million per engine, the Rocketdyne-designed and produced J-2X will cost less than half as much as the more complex Space Shuttle Main Engine (around $55 million).[19] Unlike the Space Shuttle Main Engine, which was designed to start on the ground, the J-2X was designed from inception to be started in both mid-air and in near-vacuum. This air-start capability was critical, especially in the original J-2 engine used on the Saturn V's S-IVB stage, to propel the Apollo spacecraft to the Moon. The Space Shuttle Main Engine, on the other hand, would require extensive modifications in order to add an air-start capability and to be able to restart in a near-vacuum. Near-vacuum restart capability is needed for the Ares I because it is intended to fly a Earth orbit rendezvous, and because the Orion spacecraft has limited fuel reserves. Due to these design issues, a modified Space Shuttle Main Engine would have to be "pre-fired" in a manner similar to the "Main Engine tests" conducted on the Space Shuttle Main Engines prior to the maiden flights of each NASA orbiter, including the STS-26 return to flight in 1988.[10]

System requirements review

On January 4, 2007, NASA announced that the Ares I had completed its system requirements review, the first such review completed for any manned spacecraft design since the Space Shuttle.[20] This review is the first major milestone in the design process, and is intended to ensure that the Ares I launch system meets all the requirements necessary for Constellation Program. In addition to the release of the review, NASA also announced that a redesign in the tank hardware was made. Instead of separate LH2 and LO2 tanks, separated by an "intertank" like that of the Space Shuttle External Tank, the new LH2 and LOX tanks will be separated by a common bulkhead like that employed on the Saturn V S-II and S-IVB stages. This provides a significant mass saving and eliminates the need to design a second stage interstage unit that would have to carry the weight of the Orion spacecraft with it.[14]

Schedule

See also: List of Constellation missions
A concept image of an Ares I launching from Kennedy Space Centre launchpad 39B.

NASA completed the Ares I system requirements review in January 2007.[20] Project design is to continue through the end of 2009, with development and qualification testing running concurrently through 2012. As of July 2009 flight articles are to begin production towards the end of 2009 for a first launch in June 2011.[21] Since 2006 the first launch of a human has been planned for no later than 2014,[22] which is four years after the planned retirement of the Space Shuttle.

Delays in the Ares I development schedule due to budgetary pressures and unforeseen engineering and technical difficulties have increased the gap between the end of the Space Shuttle program and the first operational flight of Ares I.[23] The total estimated cost to develop the Ares I through 2015 has risen from $28 billion in 2006 to more than $40 billion in 2009.[24]

Originally scheduled for first test flights in 2011, the Augustine Commission recently found that Ares I was unlikely to launch with a crewed payload before 2017 due to budget constraints.[25]

Role in Constellation program

An early concept image of the Ares I (right) and Ares V (left) rockets, the final designs of which differ from those shown here.

Ares I is the crew launch component of the Constellation program. Originally named the "Crew Launch Vehicle" or CLV, the Ares name was chosen from the Greek deity Ares.[3] Unlike the Space Shuttle, where both crew and cargo are launched simultaneously on the same rocket, the plans for Project Constellation outline having two separate launch vehicles, the Ares I and the Ares V, for crew and cargo, respectively. Having two separate launch vehicles will allow for more specialized designs for the different purposes the rockets will fulfill.[26]

The Ares I rocket is specifically being designed to launch the Orion Crew Vehicle. Orion is intended as a crew capsule, similar in design to the Project Apollo capsule, to transport astronauts to the International Space Station, the Moon, and eventually Mars. Ares I may also deliver some (limited) resources to orbit, including supplies for the International Space Station or subsequent delivery to the planned lunar base.[4]

Ares I has a payload capability in the 25-tonne (25-long-ton; 28-short-ton) class and is comparable to existing vehicles such as the Delta IV and the Atlas V.[4] The NASA study group that selected what would become the Ares I rated the vehicle as almost twice as safe as an Atlas or Delta IV-derived design.[27]

Design

First stage

The first stage is a more powerful and reusable solid fuel rocket derived from the Space Shuttle Solid Rocket Booster (SRB). Compared with the Solid Rocket Booster, which has four segments, the most notable difference is the addition of a fifth segment. This fifth segment will enable the Ares I to produce more thrust and burn longer.[4][28] Other changes made to the Solid Rocket Booster are the removal of the Space Shuttle External Tank (ET) attachment points and the replacement of the Solid Rocket Booster nosecone with a new forward adapter that will interface with the liquid-fueled second stage. The adapter will be equipped with solid-fueled separation motors to facilitate the disconnection of the stages during ascent.[4]

Concept image of the evolution of the Ares I design from pre-ESAS to latest developments.

In January 2008, NASA Watch revealed that the first stage Solid Rocket Booster of the Ares I could create high vibrations during the first few minutes of ascent. The vibrations are caused by sudden acceleration pulses due to thrust oscillations inside the first stage.[29] NASA officials have known about the problem since fall 2007, stating in a press release that they had wanted to solve it by March 2008.[30] NASA admitted that this problem is very severe, rating it four out of five on a risk scale. Still, NASA said they are very confident of solving this problem, referring to a long history of successful problem solving.[29] NASA also stated that this is a completely new transport system, like the Apollo or Space Shuttle systems were during their development, and that it is normal for such problems to arise during the development stage.[31]

Upper stage

The upper stage is to be propelled by one J-2X rocket engine fueled by liquid hydrogen (LH2) and liquid oxygen (LOX).[32] The J-2X is derived from the J-2 engine used on the Saturn IB and Saturn V rockets. On July 16, 2007, NASA awarded Rocketdyne a sole-source contract for the J-2X engines to be used for ground and flight tests.[33]

Although its J-2X engine is derived from an established design, the upper stage itself is wholly new. Originally based on the internal structure of the Shuttle's External Tank, the original design called for separate fuel and oxidizer tanks, separated by an "intertank" structure. Using a concept going back to the Apollo era the "intertank" structure was dropped to decrease mass, and a common bulkhead would be used between the tanks. The savings from these changes are being used to increase propellant capacity, which is now 297,900 pounds (135,100 kg).[34]

Analysis and testing

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 fly beyond the more severe danger.[35][36] Wernher Von Braun [37] said that no human should ride on a solid rocket as they were just too dangerous. [38]

Igniter tests

The Ares I igniter is an advanced version of the flight-proven igniter used on the Space Shuttle's solid rocket boosters. It is approximately 18 inches in diameter and 36 inches long, and takes advantage of upgraded insulation materials that have improved thermal properties to protect the igniter's case from the burning solid propellant.[39]

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 approximately 200 feet in length, and preliminary data showed the igniter performed as planned.[39]

See also

References

  1. ^ Boen, Brooke (July 24, 2009). "NASA–Ares Launch Vehicles". NASA. Retrieved August 5, 2009. {{cite web}}: Check date values in: |accessdate= and |date= (help)
  2. ^ Ares: NASA's New Rockets (RealMedia). NASA TV. Retrieved August 15, 2009. {{cite AV media}}: Check date values in: |accessdate= (help)
  3. ^ a b Dunbar, Brian; Wilson, Jim (November 23, 2007). "Building NASA's New Spacecraft: Constellation Work Assignments". NASA. Retrieved August 15, 2009. {{cite web}}: Check date values in: |accessdate= and |date= (help)
  4. ^ a b c d e "NASA - Ares I Crew Launch Vehicle". NASA. April 29, 2009. Retrieved May 13, 2009. {{cite web}}: Check date values in: |accessdate= and |date= (help)
  5. ^ "Technical Area 2 Heavy Lift Launch Vehicle Development Final Report" (PDF). Lockheed Martin. NASA. 1995. pp. 3–17, 3–18. Retrieved August 7, 2009. {{cite web}}: Check date values in: |accessdate= (help); Unknown parameter |month= ignored (help)
  6. ^ Mahoney, Erin (December 31, 2008). "Exploration Systems Architecture Study – Final Report". NASA. Retrieved August 5, 2009. {{cite web}}: Check date values in: |accessdate= and |date= (help)
  7. ^ "NASA Plans to Build Two New Shuttle-derived Launch Vehicles". Spaceref.com. July 5, 2005. Retrieved August 5, 2009. {{cite web}}: Check date values in: |accessdate= and |date= (help)
  8. ^ Bergin, Chris (22 July 2006). "NASA makes major design changes to CEV". NASAspaceflight.com. Retrieved August 5, 2009. {{cite web}}: Check date values in: |accessdate= and |date= (help)
  9. ^ Dunbar, Brian (May 9, 2008). "NASA Successfully Completes First Series of Ares Engine Tests". NASA. Retrieved August 5, 2009. {{cite web}}: Check date values in: |accessdate= and |date= (help)
  10. ^ a b "The J–2X Engine" (PDF). Marshall Space Flight Center. November 18, 2008. FS–2008–11–158–MSFC. Retrieved August 5, 2009. {{cite web}}: Check date values in: |accessdate= and |date= (help)
  11. ^ "To the moon and beyond: NASA's Exploration Systems Architecture Study". Wikileaks. 6 May 2009. Retrieved August 5, 2009. {{cite web}}: Check date values in: |accessdate= and |date= (help)
  12. ^ Goff, Jonathan (May 18, 2009). "More thoughts on ESAS appendix flaws". Selenian Boondocks. Retrieved August 5, 2009. {{cite web}}: Check date values in: |accessdate= and |date= (help)
  13. ^ Bergin, Chris (December 7, 2005). "ATK win CLV contract". NASAspaceflight.com. Retrieved August 5, 2009. {{cite web}}: Check date values in: |accessdate= and |date= (help)
  14. ^ a b "NASA's Ares I First Stage, Powering the Ares I Rocket for liftoff" (PDF). Marshall Space Flight Center. April 29, 2009. Retrieved August 5, 2009. {{cite web}}: Check date values in: |accessdate= and |date= (help)
  15. ^ "NASA Awards Upper Stage Engine Contract for Ares Rockets" (Press release). NASA. July 16, 2007. Retrieved 2007-07-17.
  16. ^ "NASA Selects Prime Contractor For Ares I Rocket Avionics" (Press release). NASA. December 12, 2007. Retrieved August 5, 2009. {{cite press release}}: Check date values in: |accessdate= and |date= (help)
  17. ^ Wadsworth, Harry. "History - History of Michoud". Lockheed Martin. Retrieved August 7, 2009. {{cite web}}: Check date values in: |accessdate= (help)
  18. ^ "Boeing History - Saturn V Moon Rocket". Boeing. Retrieved July 19, 2009. {{cite web}}: Check date values in: |accessdate= (help)
  19. ^ "NASA Study Finds Human-rated Delta IV Cheaper". Aviation Week. June 15, 2009. Retrieved August 9, 2009. {{cite news}}: Check date values in: |accessdate= and |date= (help)
  20. ^ a b "NASA Completes Review Milestone for Ares I Vehicle" (Press release). NASA. January 4, 2007. Retrieved August 5, 2009. {{cite press release}}: Check date values in: |accessdate= and |date= (help)
  21. ^ Boen, Brooke (July 9, 2009). "NASA Ares I-X (flight test prototype) page". NASA. Retrieved August 9, 2009. {{cite web}}: Check date values in: |accessdate= and |date= (help)
  22. ^ Connolly, John (10/11/2006). "Constellation Program Overview" (PDF). NASA. Retrieved August 9, 2009. {{cite web}}: Check date values in: |accessdate= and |date= (help)
  23. ^ "First Stage Design Problems Arise For NASA's Ares 1 Rocket". Spaceref.com. November 16, 2007. {{cite web}}: Check date values in: |date= (help)
  24. ^ "Obama plans to order full review of NASA's Ares I, Orion plans". Orlando Sentinel. May 6, 2009. {{cite web}}: Check date values in: |date= (help)
  25. ^ "US Spaceflight Gap Wider Than Thought". Aviation Week. July 28, 2009. {{cite web}}: Check date values in: |date= (help)
  26. ^ Connolly, John F. (2006). "Constellation Program Overview" (PDF). Constellation Program Office. Retrieved July 6, 2009. {{cite web}}: Unknown parameter |month= ignored (help)
  27. ^ "Part 6 of the Exploration Systems Architecture Study Final Report" (PDF). NASA. January 10, 2006. Retrieved August 5, 2009. {{cite web}}: Check date values in: |accessdate= and |date= (help)
  28. ^ "NASA To Evaluate Non-recoverable First Stage for Ares I Launch Vehicle". Spaceref.com. December 4, 2006. {{cite web}}: Check date values in: |date= (help)
  29. ^ a b Carreau, Mark (January 19, 2008). "Severe vibration problem plagues moon rocket design". Houston Chronicle. Retrieved August 5, 2009. {{cite news}}: Check date values in: |accessdate= and |date= (help)
  30. ^ Cowing, Keith (January 17, 2008). "NASA's Exploration Systems Mission Directorate Responds to Ares 1 and Orion Questions". NASA Watch. Retrieved August 5, 2009. {{cite web}}: Check date values in: |accessdate= and |date= (help)
  31. ^ Borenstein, Seth (January 18, 2008). "NASA's Next Rocket May Shake Too Much". Space.com. Retrieved August 5, 2009. {{cite news}}: Check date values in: |accessdate= and |date= (help); Unknown parameter |agency= ignored (help)
  32. ^ "Constellation Program: America's Fleet of Next-Generation Launch Vehicles, The Ares l Crew Launch Vehicle" (PDF). NASA. November 2008. Retrieved January 10, 2009. {{cite web}}: Check date values in: |accessdate= (help)
  33. ^ "NASA Awards Upper Stage Engine Contract for Ares Rockets". NASA. July 16, 2007. {{cite web}}: Check date values in: |date= (help)
  34. ^ "Ares I Upper Stage change - receives additional capacity". NASAspaceflight.com. Retrieved August 7, 2009. {{cite web}}: Check date values in: |accessdate= (help)
  35. ^ "USAF 45th Space Wing Study: Capsule~100%-Fratricide Environments (Implications for NASA's Ares-1 and Crew)". 45th Space Wing. July 16, 2009. Retrieved July 19, 2009. {{cite web}}: Check date values in: |accessdate= and |date= (help)
  36. ^ Matthew, Mark K. (July 17, 2009). "Report: No escape system could save astronauts if Ares I rocket exploded during first minute". Orlando Sentinel. Retrieved July 19, 2009. Subtitle: Report saying crew would be doomed is yet another blow to NASA's troubled Constellation program to return U.S. to the moon then Mars {{cite news}}: Check date values in: |accessdate= and |date= (help)
  37. ^ http://earthobservatory.nasa.gov/Features/vonBraun/
  38. ^ http://msl1.mit.edu/ESD10/block4/4.3_-_Challenger.pdf
  39. ^ a b Boen, Brooke (March 12, 2009). "NASA Ares Iginiter Tests". NASA. Retrieved August 5, 2009. {{cite web}}: Check date values in: |accessdate= and |date= (help)
Wikimedia Commons has media related to Project Constellation.
Retrieved from "https://en.wikipedia.org/w/index.php?title=Ares_I&oldid=309399255"