US Spaceflight for the future [update]

After several years of trade studies and political arguments, NASA administrator Charlie Bolden finally gave the Space Launch System (SLS) its official public unveiling on Wednesday. As has been known for months, the Heavy Lift Launch Vehicle (HLV) is Shuttle Derived (SD) and will use $10 billion of NASA funding through to its debut launch in 2017.

SLS History:

Not unlike most launch vehicles, SLS has suffered from a complicated birth, most of which was not of its own doing – as the political element of NASA decision making process questioned the motives of the design, and even the need for a HLV.

Regardless, the wait is now over, as the in-line SD HLV has finally been revealed in the official arena, after a heavily delayed announcement by General Bolden – flanked by lawmakers – on Wednesday.

“The next chapter of America’s space exploration story is being written, right here, right now. We’ve selected the design for a new space exploration system that will take humans far beyond Earth. This important decision will create high-quality jobs here at home and provide the cornerstone for America’s future human space exploration efforts,” noted the General in an address to employees.

In fact, the chapter – from an in-line SD HLV standpoint – was technically written years ago, and even earlier if taking into account the often-ridiculed mix of NASA engineers and space enthusiasts which created the Direct (Jupiter) alternative to the Constellation Program (CxP), itself based on an old Marshall Space Flight Center (MSFC) concept.

With the Constellation Program cancelled, the SD HLV launch system started to receive an official groundswell of interest, with General Bolden himself – back in January, 2010 – reviewing one of the subsequent trade studies, which showed the in-line HLV as the winning configuration.

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The July 8 announcement, which was even noted by Atlantis’ commander Chris Ferguson, was then cancelled, as a stalling process was put into effect, apparently under the order of the White House. This process was classed as a requirement for an independent costing assessment, to be carried out by Booz Allen. Such a process would delay the final report yet further.

Even after the cost assessment process was complete, no announcement was made, much to the anger of several Senators involved with the Authorization Act, brought to a head when a – somewhat mis-written – cost overview was leaked to the Wall Street Journal, in what is claimed to be an attempt to create large-scale opposition from within the space community.

It backfired, as the leaked report caused several meetings between political and NASA heads, based around revealing the true cost estimate findings, and ultimately leading to a joint agreement between all relevant bodies. This agreement paved the way for Wednesday’s official announcement of the vehicle.

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Heavily based on Shuttle heritage hardware, the design of the vehicle has been known for some time – as reported by this site. There will be two major roles for SLS, one is to launch cargo and one to launch the Orion (MPCV).

The core stage is an 8.4m diameter “External Tank” heritage system, with the top converted to host the Upper Stage structure, and the aft restructured to house the Main Propulsion System (MPS) – which will drive what will initially be three Space Shuttle Main Engines (RS-25Ds).

The system is designed to eventually fly with five engines in the core.

This core effort – to be hosted at the Michoud Assembly Facility (MAF) in New Orleans - is said to be one of the biggest challenges for the engineering work on SLS. Some “pathfinder” work, conducted by Boeing, has already been completed.

The role of Pratt & Whitney Rocketdyne (PWR) is now official, with SLS’ path towards its 2017 IOC (Initial Operating Capability) ready to utilize the 12 RS-25Ds available for one-off roles with SLS flights, following their transition from the Space Shuttle Program (SSP).

The Kennedy Space Center’s stock of SSMEs consists of the three orbiter sets, now removed from the vehicles, and three engines which made up the spare set.

It has also been confirmed that there will be a transition to the expendable version of the SSME, known as the RS-25E, either after the four sets of RS-25Ds have been used, or after two additional RS-25D sets have been manufactured – per reserved stock at PWR.

The eventual engine driving the core stage is confirmed as the RS-25E, a cheaper engine due to its expendable nature.

As reported, the three shuttle orbiters are now very likely to see their orbiter MPS plumbing and hardware donated to the SLS program.

Discovery’s MPS is likely to be used on test structures, while Atlantis and Endeavour’s MPS are likely to ride with SLS-1 and SLS-2.

Final evaluations are taking place into this $20m effort, with the next SLS article to overview the latest status presentations (L2).

SLS-1 and potentially SLS-2 will ride with ATK’s five segment boosters, although the competition for the confirmed booster of choice for the remainder of SLS’ lifetime will begin shortly.

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It now appears – as noted at the time – that the initial schedules and costings (leaked or otherwise) were based on worst case estimations, with only the 2017 opening launch date for the vehicle confirmed during Wednesday’s announcement.

The fear the second SLS mission – which would be the first crewed launch – would have to wait until 2021, a four year gap between flights, is now heavily associated with only a total worst case scenario, “the disaster schedule” as one source claimed.

Instead, an increased flight rate, based mainly on finding additional uses of the large fairing design and upmass capability of SLS, has been intimated. Former Space Shuttle Program (SSP) manager John Shannon has also been tasked with creating a schedule and mission architecture for the vehicle.

Work on a schedule and funding path is being worked internally by NASA and in the political arena, but as of this week, no long-term schedule can be cited until the key driver of the funding profile – which is classed as still under consideration, and not final – is officially created.

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Wednesday’s official announcement is vital to SLS, as it enables NASA to now have an approved, focused program planning effort to initiate work that will lead to the usual Systems Requirements Review and Preliminary Design Reviews.

This will lead to final determination of cost and schedule, as is normally the case with any new major vehicle development.

Next up on this path will be the procurement process, which includes meetings this week, through to next week, ahead of an industry day meeting later this month.

As mentioned, the core stage work will be the main opening challenge for the engineering teams, which in turn will drive the vehicle’s major milestone of the PDR, currently scheduled for early 2013.

Earlier key milestones (L2) cite October 24, 2011, for the SRR (System Requirements Review) Checkpoint, and February 15, 2012 for the combined SRR/SDR (System Design Review) kickoff.

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UARS – which is 35 feet long, 15 feet in diameter, and weighs 13,000 pounds – ceased its productive scientific life in 2005, whilst on its orbit at an altitude of 375 miles with an orbital inclination of 57 degrees. It was originally designed to operate for only three years.

Now out of fuel, the satellite has been dropping out of orbit, and is expected to re-enter around September 23. The problem is, NASA aren’t sure where it will re-enter until next week, which has gained media attention, given experts believe at least 26 large pieces of the satellite are expected to survive re-entry.

All NASA know at this point is the satellite will re-enter somewhere between the latitudes of northern Canada and southern South America. While the hope – via probability – is any surviving pieces of UARS will impact over water, it highlights the need to work a level of mitigation into other returning objects from space.

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RELEASE: 11-350

NASA'S UARS RE-ENTERS EARTH'S ATMOSPHERE

WASHINGTON - NASA's decommissioned Upper Atmosphere Research Satellite
(UARS) fell back to Earth between 11:23 p.m. EDT Friday, Sept. 23 and
1:09 a.m. Sept. 24, 20 years and nine days after its launch on a
14-year mission that produced some of the first long-term records of
chemicals in the atmosphere.

The precise re-entry time and location of debris impacts have not been
determined. During the re-entry period, the satellite passed from the
east coast of Africa over the Indian Ocean, then the Pacific Ocean,
then across northern Canada, then across the northern Atlantic Ocean,
to a point over West Africa. The vast majority of the orbital transit
was over water, with some flight over northern Canada and West
Africa.

Six years after the end of its productive scientific life, UARS broke
into pieces during re-entry, and most of it up burned in the
atmosphere. Data indicates the satellite likely broke apart and
landed in the Pacific Ocean far off the U.S. coast. Twenty-six
satellite components, weighing a total of about 1,200 pounds, could
have survived the fiery re-entry and reach the surface of Earth.
However, NASA is not aware of any reports of injury or property
damage.

The Operations Center for JFCC-Space, the Joint Functional Component
Command at Vandenberg Air Force Base, Calif., which works around the
clock detecting, identifying and tracking all man-made objects in
Earth orbit, tracked the movements of UARS through the satellite's
final orbits and provided confirmation of re-entry.

"We extend our appreciation to the Joint Space Operations Center for
monitoring UARS not only this past week but also throughout its
entire 20 years on orbit," said Nick Johnson, NASA's chief scientist
for orbital debris, at NASA's Johnson Space Center in Houston. "This
was not an easy re-entry to predict because of the natural forces
acting on the satellite as its orbit decayed. Space-faring nations
around the world also were monitoring the satellite's descent in the
last two hours and all the predictions were well within the range
estimated by JSpOC."

UARS was launched Sept. 12, 1991, aboard space shuttle mission STS-48
and deployed on Sept. 15, 1991. It was the first multi-instrumented
satellite to observe numerous chemical components of the atmosphere
for better understanding of photochemistry. UARS data marked the
beginning of many long-term records for key chemicals in the
atmosphere. The satellite also provided key data on the amount of
light that comes from the sun at ultraviolet and visible wavelengths.
UARS ceased its scientific life in 2005.

Because of the satellite's orbit, any surviving components of UARS
should have landed within a zone between 57 degrees north latitude
and 57 degrees south latitude. It is impossible to pinpoint just
where in that zone the debris landed, but NASA estimates the debris
footprint to be about 500 miles long.

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“We’ve got a bit more work to do,” Whitesides says. After more glide tests later this year to confirm aerodynamic and control improvements, he adds “next year we will integrate the motor and aim to conduct powered flights around the fall.”

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That manifest showed that it would take until SLS-13 for the debut of the fully evolved 130mt version of the SLS, scheduled for 2032.

The schedule was rightly criticized. However, it was always represented as a worst case scenario manifest – not least because the full mission outline for the SLS launches was yet to be created. This work is currently ongoing under the leadership of former Space Shuttle Program (SSP) manager John Shannon.

The expected realization of an improved manifest is now starting to be fulfilled, just weeks after the SLS was officially announced, in turn allowing for a full test plan effort to be worked.

SLS-1, a 70mt version of the SLS, is still expected to debut in 2017, with a “crew capable” Orion (Multi-Purpose Crew Vehicle) being sent on a test trip around the Moon. The 2021 debut of SLS/Orion for the crewed version of this mission is now being pushed to the left by two years, with a launch date of 2019.

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Unlike the Constellation Program (CxP) – which appeared to start with an unsustainable schedule, prior to almost yearly slips being noted during Program Milestone Reviews (PMRs) – sources note that all SLS mission schedules are being worked with large amounts of margin.

It has been noted that the crewed mission around the moon may even be advanced to 2018, one year after the debut SLS-1 launch, should funding projections remain stable over the coming years. Even with the two year advance to SLS-2, the downstream manifest is expected to improve to the point the evolved SLS may be ready “many years” ahead of the previous schedule.

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After over 50 years of operation, NASA is about to permanently enter the world of instant (or near instant) information exchange with the general public in a new way that largely symbolizes one of the changing ways the premiere US space agency will interact with the public and disseminate information about science operations and real-time orbital operations on the International Space Station.

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While NASA already has a fairly good track record of releasing operational and scientific data sets from its various missions, the decision has been made to proceed to the next step and take the ISS into the live data streaming environment of the 21st century through webpage and mobile device app browsing.

This means that household and personal computing and communication devices can now access the streamable information from the International Space Station and MCC Houston.

But that ability will require an increase in the need for “Mobile Device usage” including computers with internet connection, smart phones, tablets, and the creation of new apps for some of these devices to link up with the soon-to-be up-and-running ISS Live program.

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