NASA report favors SD HLV for SLS, complains Agency can’t afford 2016 target

by Chris Bergin

A preliminary NASA report, outlining plans for developing a Space Launch System (SLS) in response to the NASA Authorization Act of 2010, has put its weight behind a Inline Shuttle Derived (SD) Heavy Lift Launch Vehicle (HLV). However, the report to lawmakers complained it would not be able to build the vehicle based on the funding and schedule requirements.

SLS:

Last year, lawmakers ordered NASA to produce a report on the ‘reference designs’ for the SLS – and the Multi-Purpose Crew Vehicle (MPCV), otherwise known as Orion – following President Obama’s signing of the NASA Authorization Act of 2010 on October 11, 2010.

Led by the Human Exploration Framework Team (HEFT) – tasked with providing decision support to NASA senior leadership for planning how the Human Space Flight (HSF) program will explore beyond LEO, including the evaluation of SLS options – three RAC (Requirements Analysis Cycle) teams evaluated potential SLS configurations, with a goal to derive vehicle-level designs which can meet NASA HQ requirements.

RAC-1 studied inline, LH2 core vehicles with Solid Rocket Boosters (SRB). While this vehicle is the previously noted SD HLV, the teams avoided the use of such a name, given they were allowed to trade Space Shuttle Main Engines (SSMEs) with RS-68s, while also trading SRBs with Liquid Rocket Boosters (LRBs), in order to ensure they have the best configuration to battle with the other HLV candidates.

RAC-2 studied a Saturn V-type vehicle, utilizing an RP-1 first stage and LH2 second stage. Like RAC-1, the team was allowed to trade different engine options, within their designated configuration. RAC2 included SpaceX’s Falcon XX (huge vehicle with six Merlin 2 engines) in the trades.

RAC-3 studied vehicle designs based around several options, such as EELVs, with a large amount of latitude to study different tank sizes, including the evaluation of clusters of Atlas-sized tanks similar to how the Saturn IB first stage was built.

Based on the preliminary report presented to lawmakers on January 10, the authors note that an Inline SD HLV, utilizing five segment Solid Rocket Boosters (SRBs), Space Shuttle Main Engines (SSMEs) on the core and J-2X on the upper stage was the “winner” of the evaluations – not for the first time, based on trade studies over the last year or so.

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Executive Summary:

Opening on a positive note, the report claims the 2010 Act allows the opportunity for NASA to shape a promising future of exploration.

“With the President’s signing of the NASA Authorization Act of 2010 on October 11, 2010, NASA has a clear direction and is making plans for moving the Agency forward. NASA appreciates the significant effort that has gone into advancing this bipartisan legislation, particularly efforts by the leadership and Members of this Committee,” noted the 22 page report, available on L2.

“There are still details that the final FY 2011 appropriations outcome and the President’s FY 2012 budget request will provide, but broad guidelines have now been enacted into law. This is a time of opportunity for NASA to shape a promising future for the Nation’s space program. Today it is no longer a question of IF we will explore, but how.”
As previously outlined, the final report on the SLS and MPCV is due in the Spring, with only the preliminary findings outlined in the January 10 report.

“NASA commits to providing a follow-on report to Congress as early as the Spring 2011 timeframe to update our approach based on the plans described herein and, if necessary, modifications based on the outcome of FY 2011 appropriations and the President’s FY 2012 budget request,” the summary continued, before immediately turning the tone from the positive of a promising future, to one of negative affordability

“Guidance from the Administrator has established three principles for development of any future systems for exploration. These systems must be affordable, sustainable, and realistic.

“To date, trade studies performed by the Agency have yet to identify heavy-lift and capsule architectures that would both meet all SLS requirements and these goals. For example, a 2016 first flight of the SLS does not appear to be possible within projected FY 2011 and out year funding levels.

“Based on the guidance in the Authorization Act to take advantage of existing designs and hardware, the Agency has selected Reference Vehicle Designs for both of these vehicles as bases from which to work and which we believe most closely align to the requirements and goals of the Authorization Act. However, to be clear, neither Reference Vehicle Design currently fits the projected budget profiles nor the schedule goals outlined in the Authorization Act.

“Additionally, it remains to be determined what level of appropriations NASA will receive in FY 2011 or beyond – a factor that will impact schedule as well.”

The report adds that NASA developed a process to make progress on the Reference Vehicle Design for the SLS, while the Agency determines whether the design is sufficiently affordable, sustainable, and realistic, and also while the Agency studies other options to solicit innovative ideas and ensure the best value for the American taxpayers.

Based on objectives, affordability of heavy-lift is classed as a primary objective, second only to crew and public safety. It was also noted that NASA has initiated several industry study contracts regarding heavy-lift and propulsion, which will help inform decisions on the final detailed design concept and acquisition details for the SLS.

It was also noted that NASA will conduct studies on concepts that “were competitive in our internal trade studies” to validate, support, or challenge our current thinking in an effort to ensure an affordable design that meets Authorization Act requirements, likely to be completed by the Spring report.

“By Spring of 2011, NASA expects to have completed several key analytical steps: Analysis of the current Ares and Shuttle contracts for their applicability to the future development program; Analysis of the cost and benefits of the Reference Vehicle Design and other vehicle designs Analysis of potential initial procurement approaches,” added the report.

Interestingly, after the report claimed the budget numbers would not support the requirement of flying the SLS in 2016, the summary notes the Agency is yet to obtain independent assessments of cost and schedule, whilst such assessments may not be available until after the Spring report.

“NASA recognizes it has a responsibility to be clear with the Congress and the American taxpayers about our true estimated costs and schedules for developing the SLS and MPCV, and we intend to do so, to the best of our ability in this preliminary report, as well as in the follow-on report.

“To this end, NASA commits to obtaining independent (outside of the Agency) assessments of cost and schedule for SLS and MPCV design options as part of its decision process this Spring or Summer, and further to make these assessments public.”

The report adds that costs weren’t a major discriminator among the design options, but none of the design options studied thus far appeared to be affordable in NASA’s present fiscal conditions, citing the need for funds to be available for exploration developments such as long-duration habitats and landers.

The report also notes that work is yet to be completed on finding a number of get-wells on the cost of the SLS, which a SD HLV enables, which may include discovering “greater efficiencies” and even a potential change of design to the SD HLV.

“A feature of the Shuttle/Ares-derived reference vehicle is that it enables leveraging of current systems, current knowledge base, existing hardware and potentially current contracts, thereby providing schedule and early-year cost advantages.

“However, a 2016 first flight does not appear to be possible within projected FY 2011 and out year funding levels, although NASA is continuing to explore more innovative procurement and development approaches to determine whether it can come closer to this goal. In this context, we are still reviewing overall affordability for the longer-term, and alternative design analysis continues to be part of our strategy.

“In summary, we are committed to developing an affordable, sustainable, and realistic next-generation human spaceflight system that is in the best interests of the Nation, and we therefore look forward to working with Congress as we finalize our strategy for achieving human spaceflight to many destinations in our solar system.”

The report cites that guidance from the NASA Administrator has established three principles for development of any future systems for exploration – namely that these systems must be affordable, sustainable, and realistic, a likely reference to reassure lawmakers that the Agency is actively aiming to avoid the “unsustainable path” of the Constellation Program.

“The cost and operational capability of the systems must be sustainable over multiple Administrations and multiple Congresses. Any designs selected also must meet the test of being realistic – not relying on assumptions of increased funding or other ‘miracles’ for attainment.”

SLS Design:

Outlining the favored SLS configuration, the report preferences the Inline SD HLV, which utilizes five segment SRBs from the Constellation Program – the Ares booster ATK claims has already cost around one billion dollars in development – with the SSMEs on the first stage.

“For the SLS, the Agency has decided to use a Reference Vehicle Design that is derived from Ares and Shuttle hardware, given the Congressional direction and that our initial studies have shown that development cost is not a major discriminator in the near-term when it comes to varying heavy-lift configurations.

“The current concept vehicles would utilize a liquid oxygen/liquid hydrogen (LOX/LH2) core with five RS-25 Space Shuttle Main Engine (SSME)-derived engines, five-segment solid rocket boosters, and a J-2X based Upper Stage for the SLS. This would allow for use of existing Shuttle and Ares hardware assets in the near term, with the opportunity for upgrades and/or competition downstream for eventual upgrades in designs needed for affordable production.”

While the report again notes the caveat that their Reference Vehicle Design isn’t likely to achieve the Authorization Act’s goal of debuting in 2016, it admits the Agency is still developing an integrated schedule, to be ready in draft form by the time the Spring report is produced.

The report also references the series of minimum capabilities that the SLS vehicle must achieve, as listed in the Authorization Act.

“The vehicle must be able to initially lift 70-100 tons to LEO, and must be evolvable to 130 tons or more; The vehicle must be able to lift a MPCV; and The vehicle must be capable of serving as a backup system for supplying and supporting cargo and crew delivery requirements for the International Space Station (ISS) in the event such requirements are not met by available commercial or partner-supplied vehicles.

“The Act also directs NASA to begin development of the SLS vehicle ‘as soon as practicable after the date of the enactment’ of the NASA Authorization Act of 2010 and with the goal of achieving operational capability for the core elements not later than December 31, 2016.

Also cited in the report is the authorization of a total of $6.9 billion for SLS development over a three-year period, with $1.6 billion authorized in FY 2011.

However, the Agency appears to be struggling to work their budget assessments, given “the final SLS funding guidelines are pending the enactment of FY 2011 appropriations. The amount appropriated for SLS development efforts in FY 2011 – and the phasing of the funding in the five-year plan reflected in President’s FY 2012 budget request – are important factors that will allow NASA to finalize plans for the SLS.”

According to the FY 2011 Senate Appropriations Report funding for the SLS would open at $1.9B in FY 2011, and with a proposed cost cap of $11.5B through FY 2017 – a figure which led Senator Bill Nelson to note that “if we can’t do it (SLS) for that ($11.5 billion), we ought to question whether we can build a rocket.”

The report appears to acknowledge Senator Nelson’s comment by claiming the SLS will employ affordability, although the Agency asks for flexibility to find solutions in the schedule.

“In compliance with the Act, NASA plans to make use of current investments and workforce as appropriate. The Nation’s new SLS will leverage these critical capabilities and experience and will be designed with innovation, robustness and affordability,” added the report.

“We therefore request that the Agency continue to be given the flexibility it needs to develop the optimal solutions for SLS and the associated schedule that best benefits the Agency’s mission and is affordable in the long-term.”

SLS Studies:

The report provides recent history on the evaluations of America’s next big launch vehicle, claiming thousands of concepts have been evaluated over recent years.

“Over the course of the last decade, NASA has analysed more than 2,000 separate launch vehicle concepts and architectures, with varying figures of merit, and in concert with industry and multiple potential partners such as the Department of Defense (DOD).

“These studies have established a broad collection of reference launch vehicle configurations that the Agency continues to refine consistent with the evolving figures of merit noted earlier – where affordability has been established by the Administrator as dominant.”

The report notes that in 2009, NASA initiated a comprehensive internal study to examine the trade space for heavy-lift vehicles for the next-generation of human spaceflight systems.

“Numerous launch vehicle concepts were studied including variations of liquid oxygen/liquid hydrogen (LOX/LH2) heavy lift vehicle architectures with solid rocket boosters (side-mount and inline Shuttle derived options), and LOX/Hydrocarbon heavy lift launch vehicle architectures.

“The LOX/Hydrocarbon vehicle concepts were less mature than the LOX/LH2 concepts at the time of the study. Initial findings of this study showed that neither development schedules nor life cycle costs for the various launch vehicle concepts were discriminators and that annual recurring costs for any concept would need to be reduced through aggressive cost reduction measures.

Also listed is the May 2010 joint NASA-DOD study, which was used to determine the feasibility of a common large hydrocarbon engine that could be used by multiple stakeholders including NASA, DOD, and industry.

“The team defined engine requirements, studied the impact of fuel depots on the launch vehicle architecture, and assessed the impacts on the National industrial base if large hydrocarbon or rocket propellant (RP) engines were selected over large segmented solids,” the report added.

“Five families of RP vehicles of varying configurations were studied to meet the NASA missions; the Air Force used its current Atlas V fleet as their reference vehicle for the study. The Air Force was looking at a modest upgrade with minimal change to the existing structure of Atlas V.

“After six weeks of thorough analysis, the team concluded that there is significant synergy should NASA pursue a kerosene (RP-1) / liquid oxygen launch system. The team has identified three common engines for use on NASA’s heavy lift launch vehicle and DOD’s launch vehicle needs:

“A RP Oxygen-Rich Staged Combustion core stage engine with a thrust level of 1.0 to 1.25 million pounds (Mlbf), with an Air Force need date of 2018. A J-2X class LH2 engine with a thrust level of approximately 294 pounds (Klbf), with an Air Force need date of 2025; and A RL-10 Replacement Engine; expander cycle with a thrust level of approximately 30 Klbf), with an Air Force need date of 2020.”

No outcome of the NASA-DOD study is noted in the report, with only “additional studies were later performed to mature these concepts to the same level as the LOX/LH2 heavy-lift concepts,” tagged to the page.

Another key NASA study was performed by the Marshall Space Flight Center (MSFC) in September 2010, using a “Figures of Merit (FOM) analysis” which looked at various launch vehicle architectures that have been studied over the years. In doing so, five heavy lift launch vehicle families were reviewed.

“A 27.5-foot diameter core LOX/LH2 vehicle with five RS-25D/E core stage engines and two five-segment polybutadiene acrylonitrile (PBAN) solid rocket boosters; A 33-foot core LOX/LH2 vehicle with six RS-68 core stage engines, an Upper Stage with two J-2X engines and two five-segment PBAN solid rocket boosters,” the report listed.

“A 33-foot diameter core LOX/RP vehicle with five 2.0 Mlbf thrust RP core stage engines (Gas Generator or GG) and an Upper Stage with one J-2X Upper Stage engine; A 33-foot diameter core LOX/RP vehicle with five 1.25Mlbf thrust RP core stage engines (Oxygen Rich Stage Combustion or ORSC) and an Upper Stage with one J-2X engine; and A hybrid Heavy Lift Launch Vehicle – a clean-sheet combination of a LH2 core stage with RP strap-on boosters.

“In conducting its analysis and while maintaining a threshold safety requirement, the MSFC team performed an analytical hierarchy process and used weighted FOMs as follows: Affordability: 55 percent. Schedule: 25 percent. Performance: 10 percent. Programmatic: 10 percent.”

For this study the findings are noted, with the MSFC study showing that the 27.5-foot LOX/LH2/SSME HLV and 2Mlbf GG RP vehicles were highest rated across all of the FOMs.

“The 2.0 Mlbf RP engine vehicle scored better than the 1.25 Mlbf RP common engine because of its higher reliability (more engines would be required for 1.25 Mlbf). However, the LOX/LH2 RS-68 vehicle and the combined vehicles (LH core and RP strap-on boosters) did not fare well due to high potential costs and underrated performance,” the report added.

“In these studies, NASA used traditional cost modeling techniques, which reflect current development and operational practices. With these traditional cost models, development of these systems did not fit within the funding and schedule specified in the Authorization Act of 2010.

“In light of the studies performed to-date, NASA recognizes that in order for the exploration missions to have a sustainable manifest or cadence, future launch systems and infrastructures (and their corresponding missions) must be affordable to develop and to operate.

“The costs for design, development, test and evaluation (DDT&E) for new propulsion systems must be driven to be within the projected NASA budgets through improved practices and streamlined supporting infrastructure as well as exploring partnerships with other Government agencies and commercial partners.

“Similarly, the recurring costs of producing and operating these systems in future space exploration missions must be dramatically reduced to enable future NASA missions. NASA is committed to finding the necessary efficiencies to drive costs down and develop this system as soon as possible.”

The SD HLV Reference Vehicle Design:

Noted as providing the required lift capability requested in the NASA Authorization Act of 2010, the 27.5 foot diameter Inline SD HLV is outlined in the report as allowing for the use of existing Shuttle main engine and booster component assets in the near, whilst taking advantage of the skills of the current workforce and represents the lowest near-term costs, soonest available, and the least overall risk path to the development of the next, domestic heavy lift launch vehicle.

“Informed by the analyses described above, and consistent with the requirements of the Authorization Act, the current NASA Reference Vehicle Design assumes a 27.5-foot diameter LOX/LH2 core stage with five SSME-derived engines, also known as RS-25D/E engines, a J-2X-based Upper Stage, and two Ares-derived five-segment PBAN solid rocket boosters to provide an ultimate lift capability of approximately 130 metric tons to LEO,” continued the report.

“This design would allow NASA to use existing Shuttle main engine and booster component assets in the near term, with the opportunity for upgrades and/or competition downstream for eventual upgrades in designs needed for production of engines after flying out the current inventory of main engines and booster components. It also would allow flexibility in phasing costs for these design upgrades.

“This reference configuration would take advantage of the skills of the current workforce and allow for competition as design upgrades or configuration changes occur. Knowledge gained in the development effort could provide an informed basis for the follow-on production and operations of the launch system leading to informed, affordable production contracts.

“The overarching goal of the SLS is to enable human exploration at the highest possible safety standards and the lowest life-cycle costs for beyond-LEO missions. Based on current information and analysis, the Reference Vehicle Design represents the lowest near-term costs, soonest available, and the least overall risk path to the development of the next, domestic heavy lift launch vehicle.”

Moving forward with the SD HLV as the SLS, the report confirms the wish of lawmakers, who questioned the need for a five year study into a “game changing” HLV, based mainly around the propulsion systems.

“Selecting this SLS architecture would mean that a new liquid engine in the near term would not need to be developed, thus shortening the time to first flight as well as likely minimizing the overall DDT&E cost of the SLS.”

Despite the schedule savings made via the commonality of the SLS with Constellation and STS technology, the report is again quick to note the vehicle may not be affordable, based on the 2016 schedule goal – although efforts are being made to correct this issue ahead of the Spring report.

“However, the Reference Vehicle Design may not be affordable within expected budget levels. These issues are being considered in NASA’s ongoing trades and analyses. NASA is devising affordability strategies in this context to enable meeting the given budget constraints while also meeting the requirements of the Authorization Act.

“In FY 2011, the SLS formulation phase will pursue multiple parallel activities to help drive down the development and operations costs for the SLS. NASA plans to transition relevant work from the Space Shuttle Program and Ares Project to the new SLS Program, while also continuing to define the requirements for the new SLS system.

“NASA is performing its analyses using a government Requirements Analysis Cycle (RAC), in which ESMD, with support from the SLS Center Planning Team at MSFC, will develop a set of SLS requirements by early Spring 2011. These requirements will be informed by NASA analysis.”

Despite the Inline SD HLV preference, the report adds that all NASA (RAC) study teams will be challenged to reach completion of a preliminary analysis of high-level system requirements by March 2011, which will include initial development planning, design concept, and preliminary Level II requirements – potentially meaning alternative HLVs remain on the table.

Also clouding the issue is the inclusion of references to the 13 companies which were awarded monies to conduct studies of HLV concepts.

“In parallel with the RAC teams, on November 8, 2010, NASA announced the results of the heavy lift and propulsion study contracts that were awarded as part of a Broad Agency Announcement (BAA) issued in May 2010,” the report added.

“As part of this competitive solicitation, utilizing approximately $7.5 million in FY 2010 dollars, NASA selected 13 companies to conduct six-month studies examining the trade space of potential heavy-lift launch and space transfer vehicle concepts.”

The report adds that those trade studies will used to inform the “final” SLS vehicle design, potentially leaving the door open for the Agency to change the Reference Design Vehicle late in the evaluations.

“The BAA is focused on achieving affordability, operability, reliability and commonality at the system and subsystem levels with multiple users, including other Government, commercial, science and international partners.

“These trade studies will provide a “fresh look” at innovative launch vehicle concepts, propulsion technologies and processes that can be infused into the development of the new human exploration missions – information that will be used to help inform the overall selection and development of the final SLS vehicle detailed design.”

However, the next page of the report references how NASA “has chosen” the Reference Vehicle Design that makes “maximum use of heritage hardware designs and existing assets.”

“In addition, the Ares I (First Stage, Upper Stage, J-2X) contracts and workforce (both civil servant and industry partners) will continue along their current development plan within the existing FY 2011 Continuing Resolution funding constraints so that technologies and processes developed for that Project can be readily transferred to the SLS Program.”

The positives of the SD HLV becoming the SLS are also noted, with the report claiming such a vehicle would allow the Agency to build off previous investments, critical assets and available hardware.

“It is clear that NASA possesses valuable assets from the Shuttle Program and Ares Project that could be directly applied to the development of the SLS. To the extent practicable, NASA intends to leverage and build off of previous investments from all human spaceflight programs.

“For example, from the Shuttle Program, critical assets that could contribute to the success of the SLS development are ground handling hardware and materials from the External Tank as well as 15 remaining SSMEs (RS-25D). The Ares Project’s five-segment boosters, J-2X Upper Stage engine, and the Ares I Upper Stage manufacturing concepts and instrument unit assembly also could be applicable for the SLS.

“Using existing hardware assets, such as the Shuttle main engines and solid rocket components, can help in phasing development of improvements for affordability as these assets are flown out in early tests.”

Positives are also noted about the current workforce’s skillsets and their commonality with the SD HLV, along with the NASA facilities, such as the Michoud Assembly Facility (MAF), Stennis Space Center (SSC) and Kennedy Space Center (KSC) – the latter of which will undergo a transition into a 21st Century Launch Complex, under the guidance of SOMD.

Under the assuming current trade and analysis activities go as planned, and FY 2011 appropriations are in place, the report claims NASA plans to make final acquisition decisions for the SLS as early as Spring 2011.

“Such a decision will take into account Agency analysis on whether the existing Ares and Shuttle contracts could be used for SLS work. Data from the RAC and the BAA study contracts also will be used to help make an informed decision about SLS technical alternatives that will inform procurement and workforce matters.”

The report notes that NASA is evaluating existing Ares and Shuttle contracts – and potential money saving improvements and modifications to them – to determine whether those contracts could be used for development work on the SLS and whether doing so would be the most affordable and efficient option for developing the SLS. NASA also continues work on the elements of the Ares I Project that are most likely to feed forward into the SLS.

Report Summary:

Despite the above positives, the report ends in a negative tone regarding the assessment the vehicle’s debut would not be before the end of 2016, as much as efforts are being made to improve the projected schedule.

“The NASA Authorization Act of 2010 directs NASA to begin development of the SLS vehicle ‘as soon as practicable after the date of the enactment’ and with the goal of achieving operational capability for the core elements not later than December 31, 2016.

“While NASA will work as expeditiously as possible to meet the 2016 goal, NASA does not believe this goal is achievable based on a combination of the current funding profile estimate, traditional approaches to acquisition, and currently considered vehicle architectures.

“However, we are exploring more innovative procurement and development strategies to determine whether we can come closer to the December 31, 2016 goal. It is clear that innovative, lower cost ways of doing business and expedited processes at all levels must be implemented for SLS to achieve the first flight milestone anywhere near this goal. NASA will be pursuing such innovations as we formulate plans for SLS development.”

The report also notes that NASA is hopeful that the RAC teams and the BAA study contracts teams will develop ideas to accelerate that development timeline, such that it comes as close to the goal identified in the Authorization Act as possible, given budget realities and the need for the program to be affordable over the long-term.

Also noted is hint that a schedule get-well may be achieved by flying the SLS on a 2016 mission which would otherwise be classed as a full up test flight. However, given the lack of clarity in the reference, that can only be classed as an assumption at this stage.

“We will not commit to a date that has a low probability of being achieved. Additionally, NASA believes that utilizing heritage systems could help expedite the development process, even though launch vehicle integration challenges would still exist as a schedule threat. It is important to note, however, that it is very likely this first flight would not be ‘operational’ under traditional NASA definitions.”

The content on the SLS ends by noting the vehicle – as the SD HLV – would fulfill the requirements laid out in the Authorization Act, although the Agency does not believe it is affordable based on the projected budget levels. As such – and via the first clear admission in the report – NASA will investigate alternative concepts, in parallel with efforts to drag the Reference Design Vehicle back into the required schedule.

“In summary, the current SLS Reference Vehicle Design would utilize to the maximum extent practicable assets from the Space Shuttle Program and Ares Project. The vehicle will be able to meet the requirements specified in the NASA Authorization Act of 2010.

“The Reference Vehicle Design does not appear to be affordable within expected budget levels (based upon traditional cost models and acquisition approaches), thus NASA will also investigate alternative concepts, cost estimating and acquisition approaches over the coming months.

“The SLS acquisition strategy will not be solidified until all pertinent information is obtained to finalize a strategy and gain Agency approval. NASA will follow its Agency acquisition process by requiring the earliest possible informed decisions to ensure that programs remain consistent with NASA’s Strategic Plan and Agency commitments and are affordable and sustainable in the long-term.

“This preliminary report has highlighted the approach and content for the SLS, known as of early January 2011. In order to fully comply with direction in Section 309 of the NASA Authorization Act 2010, NASA will submit a more defined, detailed and comprehensive report to Congress as early as the Spring 2011 timeframe that will include a more mature assessment of our design, acquisition approach, and an operational readiness goal.”

(Images via L2, NASA.gov. US Senate, and Philip Metschan).

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