Progress on NASA's Space Launch System and Orion
by Ed Kyle, 01/26/2014
First SLS Core Liquid Hydrogen Barrel Segment, a
"Confidence Article" Fabricated at Michoud during 2013.
As 2014 began, development progress
was becoming more evident in NASA's Space Launch System (SLS) and Orion Multi-Purpose Crew
Vehicle (MPCV) programs.
Plans for 2014 included Exploration
Flight Test 1 (EFT-1), which would be the first flight of an Orion spacecraft.
Schedules also called for RS-25D engine testing to begin, for continued preparation of the
first solid rocket booster qualification test article, for construction of SLS core test
articles - including start of work on the core "Green Run" stage, and for
initial parts fabrication for the first SLS flight vehicle.
The Exploration Mission 1 (EM-1)
uncrewed test flight of that first SLS with a complete Orion remained scheduled for late
2017, but a 2018 date seemed more likely. It would be followed three or four years
later by the first crewed, EM-2 flight.
On July 31, 2013, NASA completed its
SLS preliminary design review (PDR). The detailed review determined that the design
of the vehicle and plans for production and ground support systems for SLS were able to
meet program objectives. The review ended the initial design and development phase
for SLS. The next milestone, called "Key Decision Point-C", was planned to
be completed during January 2014. Upon completion of "KDP-C", NASA was
expected to shift the SLS program from its design phase to its implentation - its metal
bending - phase.
In the Operations and Checkout
Building at Kennedy Space Center (KSC), Florida, the first Orion spacecraft test flight
article was in final assembly for its planned late 2014 EFT-1 test flight atop a Delta 4
Heavy launch vehicle from Cape Canaveral Space Launch Complex 37B. The cone-shaped
Orion Command Module, yet to be clad in its outer thermal protection shell, was powered up
for the first time during November 2013. Its nonfunctioning Service Module was
being prepared in the same facility for a planned mating of the two components in early
2014. During the EFT-1 mission, the Delta 4 upper stage was slated to fire after a
one-orbit coast to boost Orion to a nearly 6,000 km apogee, forcing the spacecraft to
reenter the Earth's atmosphere at nearly 9,000 meters per second to test its heat
shield. Orion would splash down below three ringsail parachutes in the Pacific Ocean
off the California coast.
First Completed Core Stage Tank Dome Test Article at Michoud, December,
Production of the EM-1 Orion Command
Module was set to begin in early 2015. The shell of the spacecraft will be
manufactured at Michoud, then shipped to KSC for outfitting. The EM-1 European
Service Module, an element based on ESA's ATV cargo spacecraft service module but
outfitted with a NASA-supplied surplus Shuttle OMS AJ10 main engine, would enter
production one year later. Both elements were aiming for mid-2017 delivery dates,
but the Service Module schedule was likely to lag due to the relatively late decision by
NASA to accept its development in a trade for Europe's ISS obligations.
At KSC Launch Complex 39, work had
begun to convert the mobile launcher built for the cancelled Ares I program for use by
SLS. The base of the towering structure will be reconfigured to support the SLS
core, with its four RS-25D liquid hydrogen/oxygen engines, and the twin five-segment solid
rocket boosters that will lift the core. At liftoff the fully fueled EM-1 SLS launch
vehicle and spacecraft will weigh more than 2,600 tonnes. Crawler Transporter 1,
which will move the massive mobile launcher, was also being modified with new generators,
roller bearings, brakes and leveling cylinders. Meanwhile, work was begun to
refurbish the flame trench at Launch Complex 39B in preparation for construction of a new
flame deflector for SLS in 2015.
VAC (Left) Will Assemble SLS
Core Stage (Right).
By early January, 2014, three of the
four massive welding tools for SLS core fabrication had been installed at NASA's Michoud
Assembly Facility in New Orleans. The fourth tool, the Vertical Assembly Center, was
expected to be completed in March, 2014. Cylinders, domes, rings and other parts of
the 8.384 meter diameter core stage are to be welded together in the massive vertical
machine. The 62.5 meter tall core will be the longest rocket stage ever built.
The first SLS Core liquid
hydrogen barrel segment, a "Confidence Article", was fabricated at Michoud by
mid-2013 in a test of a new, three-story tall Vertical Weld Center. The first SLS
core stage dome test article was welded together in the Circumferential Dome Weld
Tool using parts made in the Gore Weld Tool at Michoud before the end of
2013. Up to 450 employees were expected
to work on SLS production at Michoud.
The dome was likely a structural
test article, one of several structural test components planned to be tested beginning in
2015. A new Structural Test Article tower will be built at Marshall Space
Flight Center (MSFC) as Test Stand 4693 to test articles as large as a complete core
liquid hydrogen tank.
EFT-1 Service Module at KSC O&C Building
A "Green Run" SLS core test
article will be the first full stage assembled in the Vertical Assembly Center.
Fabrication of the Green Run stage was planned to begin in 2014. It will be used to
perform full static tests at Stennis Space Center's rebuilt B-2 test stand in 2016.
Construction of the first flight article, the EM-1 core stage, would follow beginning in
During December 2013, in preparation
for full-scale structural tests, Marshall Space Flight Center (MSFC) performed a series of
crushing tests on a tank shell made from leftover Space Shuttle External Tank
elements. The shell was compressed until it failed in the structural test area at
the Center near Huntsville, Alabama. The shell did not represent an actual SLS core
element because it was made of Aluminum Lithium with orthogrid patterns machined into the
metal. Boeing's SLS core will use AL-2219 Aluminum machined with isogrids.
EFT-1 Command Module at KSC
On January 9, 2014, engineers powered up the
SLS avionics system for the first time at MSFC. During the "first light"
test, flight software and avionics for SLS were integrated and powered. The set up
will be used to test flight software and avionics communications.
At Stennis Space Center, Mississippi, the A-1
Test Stand was being prepared for RS-25D rocket engine testing. The stand had been
used for J-2X testing until September, 2013. The first RS-25D engine was to be
placed in the stand in May, 2014 for an initial hotfire test in July, 2014.
In December, 2013, at Promontory, Utah, ATK
performed a pair of hot fire avionics tests for the SLS solid rocket boosters. The
tests operated the booster's thrust vector control (TVC) system, tested communication
between ground and flight systems, and triggered a simulated motor ignition. Both
booster avionics and electronic support equipment (ESE) was tested.
Delta 4 Heavy Configuration for ETF-1 Orion Test Flight
ATK also continued to work toward the first
qualification motor (QM-1) test firing of its SLS five segment booster, a test originally
planned for 2014 but now delayed into 2015. The delay resulted from propellant
insulation debonds and voids found in two consecutive attempts to pour a test motor aft
segment during 2013. An intense investigation was underway to discover the root
cause of the problem. Manufacturing methods that had changed since the Shuttle era
were being evaluated.
ATK performed three successful
development motor tests at its Utah test site before 2012, an effort that was originally
part of the Ares I effort. The tests took place on September 10, 2009 (DM-1), August
31, 2010 (DM-2), and September 8, 2011 (DM-3). A precursor test of a five
segment motor, assembled using an extra segment from a Shuttle four-segment motor,
occurred on October 23, 2003 (ETM-3).
Boeing planned to begin fabrication of the EM-1
ICPS (Interim Cryogenic Propulsion Stage) near the
end of 2014. The stage would be similar to the Delta 4 Heavy second stage already in
production at United Launch Alliance (ULA) in Decatur, Alabama, but would have a slightly larger liquid
hydrogen tank. Since similar stage designs were involved, spacecraft adapter
hardware developed for the Delta 4 Heavy EFT-1 mission would be used for EM-1. The
ICPS would likely be the first SLS flight hardware fully assembled for the EM-1 mission.
Potential Space Launch System Cargo Version
NASA was contemplating plans to use a
Delta 4 Heavy type payload fairing for a cargo version of SLS. A cargo SLS could be
used for advanced deep space unmanned exploration missions, or for support of NASA's human
missions. One potential early SLS cargo mission would launch a robotic asteroid
capture vehicle on an ambitious mission to attach itself to and move a small asteroid into
a "Distant Retrograde Orbit" (DRM) some 70,000 km from the Moon. There, it
would be visited by astronauts in an Orion spacecraft, possibly during the 2021 EM-2
mission. This mission, whether EM-2 or later, would be called the Asteroid Redirect
Crewed Mission (ARCM). Orion would dock to the capture vehicle, allowing astronauts
to perform a series of spacewalks to the small asteroid to collect samples.
Plans for EM-1 had been modified to make it a
25 day unmanned dress rehearsal for portions of the EM-2 asteroid retrieval mission.
During EM-1, the SLS ICPS will boost Orion Orion out of low Earth orbit toward a
lunar flyby. There Orion will fire its European Service Module engine to insert
itself first into a "deep" elliptical retrograde orbit that will extend out to
70,000 km from the Moon. At first apogee, a point that will not be reached until 10
days after launch, the ESM will fire again to place Orion into a more circular distant
retrograde orbit of the Moon. This long duration orbit will skirt past the
Earth-Moon L1/L2 Lagrangian points. Orion will stay in this
orbit for six days, during which it will only complete a portion of one orbit, before
firing its engine to drop once more into an elliptical retrograde orbit of the Moon.
While flying by the Moon, the ESM will perform a lunar flyby burn to begin the
journey back to Earth.
Potential Asteriod Redirect Crewed Mission
The ARCM crew would travel further from Earth
than any previous humans.
Both SLS and Orion continue to face challenges,
including political resistance. Former NASA Deputy Administrator Lori Garver and
former NASA Johnson Space Center Director Chris Kraft were among those who called for SLS
and/or Orion to be cancelled. Nonetheless, during January 2014 President Obama
signed a budget that assigned SLS $1.6 billion and Orion $1.2 billion during the year.
SPACE LAUNCH REPORT
by Ed Kyle