All Roads Lead to the Pad

An RS-25 engine is delivered by flatbed truck to a test stand at Stennis Space Center.
A large truck can transport a rocket component the size of one engine. But how do you transport a piece as tall as, say, the Leaning Tower of Pisa?

NASA is preparing for the first of many flights of the agency’s Space Launch System rocket and Orion spacecraft. Every day we’re making progress toward their first integrated test flight. Today, that work is taking place at numerous sites around the country, but the work of that nationwide team is firmly focused on one place – the launch pad.

Hundreds of companies across every state have been a part of SLS and the Orion crew spacecraft, many of them small businesses providing specialized components or services. That work comes together at NASA and prime contractor facilities where the “big pieces” are assembled before it all comes together on the launch pad at NASA’s Kennedy Space Center in Florida.

A crane lifts the ICPS test article out of a shipping container.
A test article of the Interim Cryogenic Propulsion Stage was delivered to Marshall Space Flight Center from United Launch Alliance in June.

1) Second Stage, From Alabama to Florida by Barge

Some of the pieces have a relatively direct route to the launch pad. At Marshall Space Flight Center in Huntsville, Alabama, where the SLS program is managed, for example, the flight unit for the Orion Stage Adapter (OSA) that will connect the SLS second stage to the crew spacecraft is being welded, and welding will begin next month on the Launch Vehicle Stage Adapter (LVSA) that will connect the core and second stages. When completed, the LVSA will travel by barge to the gigantic Vehicle Assembly Building (VAB) at Kennedy Space Center (KSC) in Florida, where final stacking of SLS and Orion will take place. The smaller OSA has the option of barge or truck, and after arriving in Florida, will make a stop at a facility where 13 CubeSats will be installed before continuing on to the VAB.

Half an hour away, the second stage of the rocket, the Interim Cryogenic Propulsion Stage (ICPS), is being completed at the United Launch Alliance facility in Decatur, Alabama. The process for the ICPS will be one step longer – after being barged from Decatur to Florida, the stage will be prepared for flight at a payload processing facility before being moved to the VAB for stacking.

Booster segments being delivered by train to Kennedy Space Center during the space shuttle era
Booster segments being delivered by train to Kennedy Space Center during the space shuttle era.

2) Boosters, From Utah to Florida by Train

Propellant is already being cast into booster segments for the first flight of SLS. The boosters will be transported by train from an Orbital ATK facility in Utah to Florida. Since the 17-story-tall boosters are far too long to be transported in one piece, the boosters will be transported in segments. They’ll arrive at a processing facility at Kennedy before being moved to the VAB where they’ll be stacked vertically and joined by the rest of the rocket.

Cutaway view of the core stage inside the Pegasus barge
NASA’s large Pegasus barge will be able to transport the SLS core stage, which will be more than 200 feet long.

3) Engines and Core Stage, From Mississippi to Louisiana to Mississippi to Florida By Barge

This one’s a little more complicated. RS-25 core stage engines are currently in inventory at Stennis Space Center in Mississippi, where engine testing is taking place. The core stage hardware for the first launch of SLS is currently being welded at Michoud Assembly Facility in New Orleans. The engines for the first flight will be transported from Stennis to Michoud, and integrated into the first core stage when it’s completed. The core stage with engines will then be transported back to Stennis, where the 212-foot-tall stage-and-engine assembly will be placed into a test stand and all four engines will be fired together in the largest liquid-engine ground test since Apollo. After the test, plans call for the stage to be shipped to Kennedy by barge, where it will be brought to the VAB for assembly with the rest of the rocket.

Artist concept of SLS and mobile launcher on the crawler transporter.
The crawler-transporter is capable of transporting 18 million pounds from the VAB to the launch complex.

4) Rocket, From VAB to Launch Pad via Crawler

Once all of the elements have arrived at the VAB, they’ll be stacked vertically and prepared for launch. The large crawler transporter will bring the mobile launcher with tower to the rocket, and will then carry rocket and launcher together to the launch pad. Which leaves only one last step:

5) Orion, From Launch Pad to Deep Space, via Rocket

NASA is on track for the first mission to launch no later than November 2018 from Florida. The first test flight of SLS and Orion will be incredible, and it will pave the way for our second exploration mission – our first with crew aboard the spacecraft. As these missions continue to come together, we’re closer to sending astronauts to Red Planet than at other point in our history. All the work we’re doing together today will continue to enable that journey in the future.

Join in the conversation: Visit our Facebook page to comment on the post about this blog. We’d love to hear your feedback!

SLS Avionics: The Brain Without a Body

By Martin Burkey

If you compared NASA’s powerful Space Launch System (SLS) rocket to a human body, the avionics and software would be the nervous system and brain that monitor the body’s condition and makes and sends decisions. Just a few of the hundreds of operations that they make include: liquid propellant flow, engine throttling, engine and booster exhaust nozzle steering, trajectory updates, receiving and sending data to the crew and ground control, and responding to off-nominal issues such as wind gusts or an engine failure.

The avionics are required to work in environments of temperature, pressure, sound, etc. that no human body – and actually few machines – could tolerate. So everything from the boxes, to the boards, to the individual processors are “ruggedized” and tested at every step in development to survive launch.

Ultimately the avionics boxes and software have to work perfectly. But how can you be sure without putting it on the world’s largest rocket and seeing how it works? That’s the focus of the Integrated Avionics Test Facility – or IATF – at NASA’s Marshall Space Flight Center, where the computer, routers, processors, power, and other black boxes and software collectively known as “avionics” are being tested in preparation for the planned 2018 first flight of SLS.

Possibly the coolest thing about the test facility is that it can create an artificial vehicle operating in an artificial world and virtually “fly” SLS hundreds of times – from pre-launch activation and checkout to liftoff to core stage separation at about 17,500 miles per hour and 100 miles in space – to test the entire avionics package.

Expanded view of SLS showing various avionics locations.
Location of avionics aboard SLS Block 1.

Avionics can be found all over SLS: in the booster aft skirt and forward skirt, the core stage engine controllers mounted on the engines themselves, in the core stage engine section, intertank, and forward skirt, in the launch vehicle stage adapter, and in the Interim Cryogenic Propulsion Stage. Of course, avionics for the Orion crew vehicle are also linked in to the performance of the whole vehicle. So basically top to bottom.

An overhead view of the SLS IATF at Marshall Space Flight Center.
The heart of the Integrated Avionics Test Facility at NASA’s Marshall Space Flight Center. The Systems Integration Test Facility-Qualification is shown left background. The System Integration Lab is in the foreground. The SLS booster Hardware In the Loop facility is in the middle background.

Inside the test facility, the vehicle avionics boxes are mounted on a semi-circular, 18-foot-tall frame in the same relative position they will be inside SLS – right down to the length of the connecting cables. Outside the frame, several large towers house the equipment for simulating the SLS “world” and running test after test.

The virtual world of SLS is created by a pair of software tools, ARTEMIS and MAESTRO. They stand for A Real-Time Environment for Modeling, Integration and Simulation (ARTEMIS) and Managed Automation Environment for Simulation, Test, and Real-Time Operations (MAESTRO). (How do engineers come up with this stuff?) ARTEMIS is a suite of computer models, simulations and hardware interfaces that simulates the SLS and its virtual “world.” For instance, it simulates the Earth’s rotation, gravity, propellant tank sloshing, vehicle bending in flight, engine and booster pressure, temperature and thrust, and weather, from hot sunny days to cold stormy nights, and inputs from the Orion crew vehicle and launch facilities. In fact, ARTEMIS has far more lines of software code than SLS itself. MAESTRO serves as the test conductor for the virtual missions. This software configures and controls test operations, sets up the external conditions, monitors the tests, and archives all test data for analysis. That’s where engineers and software writers find out if their code needs fixing or supplementing.

The actual flight avionics for SLS will never be tested in this facility – only their flight-like equivalents. The actual flight avionics will be installed directly into the core stage at the Michoud Assembly Facility in Louisiana and tested there prior to flight. The test team at Marshall can already say that they’ve flown SLS “virtually” thousands of time to help ensure that SLS flies safely on its first real mission in a couple of years.


Join in the conversation: Visit our Facebook page to comment on the post about this blog. We’d love to hear your feedback!

Behind the Scenes at QM-2: Getting Ready to Test the World’s Largest Solid Rocket Motor

By Beverly Perry

For two monumental minutes on June 28, the Space Launch System (SLS) solid rocket boosters — the largest ever built for flight — will fire up in an amazing display of power as engineers verify their designs in the last full-scale test before SLS’s first flight in late 2018. Each piece of hardware that’s qualified and each major test — like this one, dubbed QM-2 — puts NASA one step closer on its Journey to Mars.

The smoke and fire may last only two minutes, but engineers at NASA’s Marshall Space Flight Center in Huntsville, Alabama and Orbital ATK in Promontory, Utah have been preparing weeks — even months — in advance for the static test of Qualification Motor 2 (QM-2). Here’s a behind-the-scenes look at what goes into getting ready to fire up the largest and most powerful solid rocket motor ever built for flight.

T (for test) minus weeks and months. In the months prior to the test, propellant-filled segments began arriving at Orbital ATK’s Test Bay T-97 after being cast in nearby facilities. Many of these segments are veterans of space shuttle flights. In fact, the various metal case segments that comprise the five-segment QM-2 motor flew on 48 shuttle flights!

T minus 14 days. In the two weeks leading up to the test, Orbital ATK engineers begin dry runs that simulate the final test as closely as possible (without the smoke and fire). They put the motor and associated systems through their paces no fewer than 11 times before the big day to ensure not only that all systems are functioning as expected, but also that the test will be executed properly. “We only get one shot at firing the rocket motor,” says Dr. Janica Cheney, Orbital ATK’s director of Test Operations. “All the dry runs and other preparations that take place ahead of time are critical to ensuring we get the data we need from this test firing.”

NASA and Orbital ATK test SLS Qualification Motor-2 (QM-2) before first flight.
Are you ready? It’s time for the final full-scale test before the first flight test of the SLS solid rocket motor June 28 at 10:05 a.m. EDT (8:05 a.m. MDT). Many cameras record data during the test, such as this one which captures nozzle plug performance during the test.

T minus 24 hours. For this final full-scale static test, engineers have 82 goals, or test objectives, they need to measure and evaluate. One day before the test, it’s crunch time; caffeine’s flowing as engineers work around the clock the day before the test to ensure all systems function properly and all necessary data can be collected.

T minus 8 hours. Game day. There’s focus — and excitement. There are two more dry runs leading up to the test. Engineers, technicians and operators are “on station,” — present and accounted for at key locations such as the test bay, the instrument rooms and the control bunker. When you hear “control bunker,” think mission control — a command and control center that directs every aspect of the test, similar to what you see at mission control during a launch. Time flies during the final eight hours before the test.

Orbital ATK’s Test Bay housing rolls back to reveal Qualification Motor-2 (QM-2).
At T minus 6 hours with a “go” decision for testing QM-2, engineers at Orbital ATK will roll back the booster test bay housing so the massive motor can be fired.

T minus 6 hours. At 4:05 a.m. EDT (2:05 a.m. MDT), engineers and managers at Orbital ATK and NASA will make a “go” or “no go” decision on testing that day. Assuming the test’s a go, technicians “roll back” Orbital ATK’s specially designed moveable test bay housing and begin running final checks to make sure everything is ready. “We check the status of all the data and control systems, the test bay, the motor preparation and weather conditions,” Cheney says.

Weather is one variable that can halt the QM-2 test. “We make sure there’s no lightning in the area; no high winds; no storms,” explains Orbital ATK Fire Chief Blair Westergard. “We also establish fire breaks. Along with the Box Elder County Fire District, we’re prepared to extinguish any secondary wildfires too.”

Engineers also make sure cameras are ready to film and all data recording systems are online and functioning properly. Orbital ATK Security ensures the area around the test is clear.

T minus 3 hours. Crowds begin to gather as the public viewing area near Promontory off State Route 83 opens at 7:30 a.m. EDT (5:30 a.m. MDT). Orbital ATK Security directs traffic with the help of the Utah Highway Patrol and provides crowd control support to ensure everything remains orderly — vital when 10,000 people are in attendance.

https://www.youtube.com/watch?v=https://www.youtube.com/watch?v=c-xrhYKC0q4[/embedyt]

If you do not see the video above, please make sure the URL at the top of the page reads http, not https.

T minus 1 hour. The formal countdown commences; the public address system broadcast begins. The crew in the test bay begins final procedures to prepare the booster for testing.

T minus 9 minutes. Final system and timing checks are underway.

T minus 4 minutes. A “go for test” announcement sounds from the public address system.

T minus 1 minute. A siren begins; it will blare through T minus 20 seconds.

T minus 45 seconds. The “Safe and Arm” system sequence begins, which arms the motor. The Safe and Arm device is remotely activated from the “safe” position into the “armed” position, allowing the motor to ignite when the “fire” command is given.

T minus zero. At 10:05 a.m. EDT (8:05 MDT), two minutes of pure awesome commence as the gigantic motor burns through about five and a half tons of propellant each second during the approximately two-minute test. Inside the control bunker, there will be jubilation — and relief. “This is serious business — this is rocket science,” Cheney emphasizes. “But there’s nothing better than the smoke and fire and the data that comes with it when you’ve had a successful day. Our success is NASA’s success — we don’t do it alone.”


Join in the conversation: Visit our Facebook page to comment on the post about this blog. We’d love to hear your feedback!

Three Cool Facts About QM-2

By Beverly Perry

The countdown to the last full-scale test firing of the massive Space Launch System (SLS) solid rocket boosters has begun. Mark your calendars: June 28, 8:05 a.m. MDT.

Expect two minutes of shock and awesome as the flight-like motor burns through about six tons of propellant each second during the test. With expanding gases and flames exiting the nozzle at speeds in excess of Mach 3 and temperatures reaching 3,700 degrees Fahrenheit, say goodbye to some of the sand at Orbital ATK’s test facility in the Utah desert because after the test, the sand at the aft, or rear, end of the booster motor will be glass.

NASA and Orbital ATK are rolling back the house and rocking the Utah desert for QM-2 June 28.
NASA and Orbital ATK are rolling back the house and rocking the Utah desert for QM-2 June 28.

The 154-foot long Qualification Motor 2 (QM-2) consists of the five propellant-filled segments in the middle of the booster; the aft skirt is also part of the test, but the forward assembly (nose cap, forward skirt) won’t be. (See our Boosters 101* infographic if you need a refresher on booster parts and assemblies). The test will broadcast live on NASA TV and our Facebook page. We will also live tweet from @NASA_SLS on Twitter.

For those watching at home (or work), here are three cool things that might not be so obvious on the screen, in countdown order.

3. This motor’s chill. QM-2’s been chilling — literally, down to 40 degrees — since the first week in May in Orbital ATK’s “test bay housing,” a special building on rails that moves to enclose the booster and rolls back so the motor can be test-fired. Even though SLS will launch from the normally balmy Kennedy Space Center in Florida, temperatures can vary there and engineers need to be sure the booster will perform as expected whether the propellant inside the motor is 40 degrees or 90 degrees (the temperature of the propellant during the first full-scale test, Qualification Motor 1 or QM-1).

2. This booster’s on lockdown. If you happen to be near Promontory, Utah on June 28, you can view the test for yourself in the public viewing area off State Route 83. And don’t worry, this booster’s not going anywhere — engineers have it locked down. The motor is held securely in place by Orbital ATK’s T-97 test stand.

During the test, the motor will push against a forward thrust block with more than three million pounds of force. Holding down the rocket motor is more than 13 million pounds of concrete — most of which is underground. The test stand contains a system of load cells that enable engineers to measure the thrust the motor produces and verify their predictions.

Solid rocket booster test burns so hot it turns sand to glass.
The solid rocket motor test firing will burn so hot the sand at the aft end of the motor will turn to glass.

Putting out the fire at the end of the test is the job of the quench system, which fills the motor with carbon dioxide from both ends of the test stand. A deluge system sprays water on the motor to keep the metal case from getting too hot so the hardware can be re-used. Both the quench and deluge systems had to be upgraded to handle the heat and size of the big five-segment boosters.

1. Next time, it’s for real. These solid rocket boosters are the largest and most powerful ever built for flight. They’ve been tested and retested in both full-scale and smaller subsystem-level tests. Engineers have upgraded and revamped vital parts like the nozzle, insulation and avionics control systems. They’ve analyzed loads and thrust, run models and simulations, and are nearing the end of verifying their designs will work as expected.

Most of this work was necessary because, plainly put, SLS needs bigger boosters. Bigger boosters mean bolder missions – like around the moon during the first integrated mission of SLS and Orion. So the next time we see these solid rocket motors fire, they will be propelling SLS off the launch pad at Kennedy Space Center and on its first flight with Orion. For real.

Next time: Behind the Scenes at QM-2: Getting Ready to Test the World’s Largest Solid Rocket Motor.


Join in the conversation: Visit our Facebook page to comment on the post about this blog. We’d love to hear your feedback!

Small Hitchhikers Ride through the Galaxy

By Beverly Perry

On the first launch of the Space Launch System (SLS), America’s next-generation heavy-lift rocket, the Orion Stage Adapter (OSA) will carry 13 CubeSats, or boot box-sized science and technology investigations, that will help pave the way for future human exploration in deep space. Engineers and technicians at NASA’s Marshall Space Flight Center have built the main structure of this hardware that will be part of the rocket when it lifts off from Launch Complex 39B at NASA’s modernized spaceport at Kennedy Space Center in Florida.

The Orion Stage Adapter being designed and manufactured at NASA’S Marshall Space Flight Center in Huntsville, Ala. nears completion.
Jennifer Takeshita, the lead for friction stir welding at Teledyne Brown Engineering, compares a model of the Orion Stage Adapter (OSA), including brackets to secure CubeSats during their spaceflight, to the flight hardware nearing completion at Marshall Space Flight Center.

The Orion Stage Adapter does exactly what its name indicates: it connects the Orion spacecraft to the second stage of the launch vehicle. Using enormous friction-stir welding machines, engineers just finished welding three large panels into a ring that is 18 feet in diameter and 5 feet high. With this welding complete, it’s time for analysis. The main structural ring is currently undergoing nondestructive analysis using 3-D structured light scanning and photogrammetry, which creates a computer model using photography, to ensure hardware was built to design specification.

Three-dimensional structured light scanning, photogrammetry, and solid modeling software are helping engineers visualize the minute differences between the OSA that was designed and the hardware that was built.
Engineers use 3-D structured light scanning and photogrammetry to analyze the main structure of the Orion Stage Adapter (OSA) at Marshall Space Flight Center. Targets for the optical scanner and SLR camera can be seen on the aluminum structure. Solid modeling software will combine the images into a single computer model so engineers can compare finished hardware to the design.

Next, engineers will trim it, weld upper and lower rings onto the large ring, machine it to final dimensions, apply paint, and install the diaphragm, a barrier that separates SLS from Orion. After that, installation of cables and the brackets that will secure the secondary payloads during their spaceflight will complete this critical piece of flight hardware.

The 13 CubeSat secondary payloads will be some of the first small satellites to explore deep space and answer critical questions relevant to NASA’s future exploration plans. These small but mighty scientific investigations include ten satellites from U.S. industry, government, and commercial partners as well as the three CubeSats being built by international partners.


Join in the conversation: Visit our Facebook page to comment on the post about this blog. We’d love to hear your feedback!

The Rocket Comes to the Rocket City

By David Hitt

Over the next year, the rocket comes to the Rocket City in a big way.

Huntsville, Alabama, a.k.a. “Rocket City,” is home to NASA’s Marshall Space Flight Center, where today the Space Launch System (SLS), the powerful rocket NASA will use for human exploration of deep space, is being developed.

More than six decades ago – before NASA even existed – Huntsville laid claim to the nickname thanks to its work on missiles and rockets like the Juno that launched the first American satellite or the Redstone used for the first Mercury launches.

In the years since, Huntsville, and Marshall, have built on that legacy with work on the Saturn V rockets that sent astronauts to the moon, the space shuttle’s propulsion systems, and now with SLS.

New test stand at Marshall Space Flight Center
A steel beam is “flown” by crane into position on the 221-foot-tall (67.4 meters) twin towers of Test Stand 4693 during “topping out” ceremonies April 12 at NASA’s Marshall Space Flight Center in Huntsville, Alabama.

While the program is managed at Marshall Space Flight Center, contractors around the country are building the rocket. Engines are being tested in Mississippi. The core stage is being built in Louisiana. Booster work and testing is taking place in Utah. Aerospace industry leaders and more than 800 small businesses in 43 states around the country are providing components.

The Marshall team has also been involved with the hardware, largely through testing of small-scale models or smaller components. The center also produced the first new piece of SLS hardware to fly into space – a stage adapter that connected the Orion crew vehicle to its Delta rocket for Exploration Flight Test-1 in 2014 (See Orion’s First Flight for more.) The same adapter will connect Orion to SLS for their first flight in 2018.

The top half of a test version of the SLS Launch Vehicle Stage Adapter on a weld tool at Marshall
Workers prepare the top half of a test version of the SLS Launch Vehicle Stage Adapter. The completed adapter will undergo structural testing at Marshall later this year.

Now, however, big things are happening in the Rocket City. The new Orion stage adapter for the upcoming launch is being built. The larger Launch Vehicle Stage Adapter, which will connect the core and second stages of the rocket, is being built at Marshall by contractor Teledyne Brown Engineering. This year, test versions of those adapters and the Interim Cryogenic Propulsion Stage (ICPS) will be assembled into a 56-foot-tall stack, which will be placed in a test stand to see how they handle the stresses of launch.

Those test articles built locally will be joined by larger ones produced at the Michoud Assembly Facility outside New Orleans. Test versions of the rocket’s engine section, oxygen tank and hydrogen tank will be shipped by barge from Michoud to Marshall. Two new test stands – one topped out last month at 221 feet tall – have been built at Marshall, joining historic test stands used to test the Saturn moon rockets.

The Payload Operations Center at Marshall Space Flight Center
In addition to rocket development, Marshall is involved in numerous other efforts, including supporting all U.S. scientific research conducted aboard the International Space Station.

Fifty-five years ago this month, Alan Shepard became the first American in space riding on a Redstone rocket, named for the Huntsville army base where his rocket had been designed – Redstone Arsenal. Today, Marshall, located on the same red clay that gave the arsenal and rocket their name, is undertaking perhaps its largest challenge yet – building a rocket to carry humans to the red stone of Mars.

Huntsville grew substantially from its small Southern town roots during its early days of rocket work in the 1950s and ‘60s, and Marshall has gone on to be involved in projects such as Skylab, Spacelab, the Hubble Space Telescope and the International Space Station, to name a few. But despite branching out its work both in space and other technology areas, Huntsville remains the Rocket City.

…After all, we built this city on a rocket role.


Join in the conversation: Visit our Facebook page to comment on the post about this blog. We’d love to hear your feedback!

Next Generation Wants Its Mars Shot

By Beverly Perry

We don’t know who will take those first steps on Martian soil, ushering in the age of humans as a multi-planetary species. But we do already know a couple things about those first intrepid explorers: They’re taking steps on Earth right now; and they belong to a generation that is tech-savvy, and raised on the internet and social media. But do today’s students think about exploring beyond this world and into deep space?

University of Illinois Urbana-Champaign student rocketry team
Members of the University of Illinois Urbana-Champaign’s rocketry team said at NASA’s Student Launch competition that they look forward to NASA’s Journey to Mars and aspire to be a part of it.

“Every day – we can’t get enough of that stuff!” said Ben Collins from the University of Illinois Urbana-Champaign on a recent windy morning that was spent launching rockets in a field north of Huntsville. Collins and his teammates were among 51 student rocketry teams that competed in various challenges and sent their amateur rockets soaring during the 16th annual Student Launch rocketry challenge April 13-16.

Tuskegee University’s rocketry team at NASA’s Student Launch competition
Members of Tuskegee University’s rocketry team enjoy their day at NASA Marshall’s Student Launch.

At this year’s Student Launch, middle and high school students and university computer scientists, physicists and engineers of all stripes (aerospace and mechanical were particularly well-represented) got to tour NASA’s Marshall Space Flight Center, the center responsible for developing the Space Launch System (SLS), the country’s next-generation heavy-lift launch vehicle.

While there, the students heard from a member of their generation actively involved in designing and engineering SLS: Marshall engineer Kathryn Crowe, who is part of a generations-spanning workforce blending fresh thinking with years of experience. (See Time Flies: Next-Generation Rocket is the Work of Generations for more about Kathryn’s work.)

For some, the competition – and the visit – were a taste of things to come.

“My biggest career goal is to work on the Journey to Mars – to somehow be a part of it,” said Brandon Murchinson, also of the University of Illinois Urbana-Champaign. “I think SLS is incredible. As someone who’s always been interested in space exploration and travel, it’s why I chose this career path.”

NASA’s call for new astronauts earlier this year also made an impact on the future engineers and scientists at the Student Launch. Paul Grutzmacher, a 17-year-old senior at St. Vincent-St. Mary High School in Akron, Ohio, said that his career goal is to become a pilot for the Orion crew vehicle that will launch on SLS. “SLS excites me because it’s supposed to take us farther than we’ve gone before and it’s also our next heavy lifter,” he added.

St. Vincent-St. Mary High School rover at 2016 Student Launch.
St. Vincent-St. Mary High School’s Project Manager Raykwon Wookdruff describes the team’s rover, which autonomously located the team’s downed rocket, providing a proof of concept that an autonomous rover on Mars could locate and retrieve a supply rocket without astronauts having to leave the vicinity of their habitat.

Grutzmacher thinks he’s got the right stuff to fly on SLS, but so does Vanderbilt University’s Rebecca Riley, a senior computer science major who plans to continue her education in particle physics. “I think we’re all pretty excited that we might be the right age to be going to Mars. I’m like, Man, that’s going to be me going to Mars!”

These students recognize the value in missions that build expertise in long-duration spaceflight – and the technological spinoffs that arise from the process. To hear them tell it, long timelines just don’t scare them.

Auburn University’s student rocketry team tracks progress on America’s next great rocket by following social media and events like solid rocket booster static test firings and RS-25 main engine tests. “Social media makes it a lot more tangible,” said Auburn’s Burak Adanur. “And I think it gives people something to look forward to,” he said.

Vanderbilt University’s Andrew Voss has participated in the Student Launch over the past four years. “I have seen a lot of work go down,” he said. “And I like seeing the test stands because the work that goes into testing is a feat of engineering.” Check out our recent blog post on Engine 2059 for more about how an engine helped test a test stand.

Tech-obsessed students have no trouble spouting off advancements that have arisen from America’s space program: cell phone cameras, scratch-resistant sunglasses, memory foam, and the list goes on. Vanderbilt’s Voss said, “That’s part of what NASA’s always done, and what could come out of SLS is not just spaceflight, but technology that drives the world forward.”

Vanderbilt University rocketry team launches rocket
Members of Vanderbilt University’s student rocketry team spoke about the future of deep space exploration after successfully launching their rocket.

“I think that’s one of the most important aspects to space exploration,” said Auburn’s Adanur. “We have to go space because it’s a mechanism – it’s a crucible – that will change us as a society and give us new technologies. I think it has more of a ripple effect than most people think.”

Chris Lorenz of the University of Illinois at Urbana-Champaign said he sees the value of NASA’s proving ground missions to build up for human Mars landings. “I’m a big fan of what NASA does in robotic exploration. It’s smart to go unmanned and build up infrastructure first before attempting manned missions,” he said.

Vanderbilt’s Mitch Masia said that while proving ground missions are necessary, deep space exploration really gets people going. “The space station is awesome and a huge feat and deep space missions will get people even more excited.” Case in point: Worldwide amazement and wonder at the photos of Pluto NASA’s New Horizons spacecraft has been sending back to Earth.

Sylvania Northview High School rocketry team at NASA’s Student Launch competition
Members of Sylvania Northview High School’s rocketry team explain their project to other students during the Rocket Fair at NASA’s Marshall Space Flight Center the day before launch.

Participants at the Student Launch emphasized that their generation wants its chance to make history. They want their Mars shot. “I think SLS will bring our generation together,” said Michael D’Onofrio, a 17-year-old senior at Sylvania Northview High School in Sylvania, Ohio. “Something that’s greater than where we are – going beyond Earth – will bring us together.”

Vanderbilt’s Riley said, “I’m excited about SLS in a very patriotic way. SLS and going to Mars is that big goal that we can all get behind and be excited about as an American people.”


Join in the conversation: Visit our Facebook page to comment on the post about this blog. We’d love to hear your feedback!

We’ve Got (Rocket) Chemistry, Part 1

Written by Beverly Perry

What do water and aluminum have in common?

If you guessed that water and aluminum make SLS fly, give yourself a gold star!

Chemistry is at the heart of making rockets fly. Rocket propulsion follows Newton’s Third Law, which states that for every action there is an equal and opposite reaction. To get a rocket off the launch pad, create a chemical reaction that shoots gas and particles out one end of the rocket and the rocket will go the other way.

What kind of chemical reaction gets hot gases shooting out of the business end of a rocket with enough velocity to unshackle it from Earth’s gravity? Combustion.

Whether it’s your personal vehicle or a behemoth launch vehicle like SLS, the basics are the same. Combustion (burning something) releases energy, which makes things go. Start with fuel (something to burn) and an oxidizer (something to make it burn) and now you’ve got propellant. Give it a spark and energy is released, along with some byproducts.

For SLS to fly, combustion takes place in two primary areas: the main engines (four Aerojet Rocketdyne RS-25s) and the twin solid rocket boosters (built by Orbital ATK) that provide more than 75 percent of thrust at liftoff. Combustion powers both propulsion systems, but the fuels and oxidizers are different.

RS-25 engine during testing
Steam clouds, the product of the SLS main engines’ hydrogen-oxygen reaction, pour from an RS-25 engine during testing at NASA’s Stennis Space Center.

The RS-25 main engines are called “liquid engines” because the fuel is liquid hydrogen (LH2). Liquid oxygen (LOX) serves as the oxidizer. The boosters, on the other hand, use aluminum as fuel with ammonium perchlorate as the oxidizer, mixed with a binder that creates one homogenous solid propellant.

Making water makes SLS fly

Hydrogen doodleHydrogen, the fuel for the main engines, is the lightest element and normally exists as a gas. Gases – especially lightweight hydrogen – are low-density, which means a little of it takes up a lot of space. To have enough to power a large combustion reaction would require an incredibly large tank to hold it – the opposite of what’s needed for an aerodynamically designed launch vehicle.

To get around this problem, turn the hydrogen gas into a liquid, which is denser than a gas. This means cooling the hydrogen to a temperature of ‑423 degrees Fahrenheit (‑253 degrees Celsius). Seriously cold.

Oxgen doodleAlthough it’s denser than hydrogen, oxygen also needs to be compressed into a liquid to fit in a smaller, lighter tank. To transform oxygen into its liquid state, it is cooled to a temperature of ‑297 degrees Fahrenheit (‑183 degrees Celsius). While that’s balmy compared to LH2, both propellant ingredients need special handling at these temperatures. What’s more, the cryogenic LH2 and LOX evaporate quickly at ambient pressure and temperature, meaning the rocket can’t be loaded with propellant until a few hours before launch.

Once in the tanks and with the launch countdown nearing zero, the LH2 and LOX are pumped into the combustion chamber of each engine. When the propellant is ignited, the hydrogen reacts explosively with oxygen to form: water! Elementary!

2H2 + O2 = 2H2O + Energy

This “green” reaction releases massive amounts of energy along with superheated water (steam). The hydrogen-oxygen reaction generates tremendous heat, causing the water vapor to expand and exit the engine nozzles at speeds of 10,000 miles per hour! All that fast-moving steam creates the thrust that propels the rocket from Earth.

It’s all about impulse

But it’s not just the environmentally friendly water reaction that makes cryogenic LH2 a fantastic rocket fuel. It’s all about impulse – specific impulse. This measure of the efficiency of rocket fuel describes the amount of thrust per amount of fuel burned. The higher the specific impulse, the more “push off the pad” you get per each pound of fuel.

The LH2-LOX propellant has the highest specific impulse of any commonly used rocket fuel, and the incredibly efficient RS-25 engine gets great gas mileage out of an already efficient fuel.

But even though LH2 has the highest specific impulse, because of its low density, carrying enough LH2 to fuel the reaction needed to leave Earth’s surface would require a tank too big, too heavy and with too much insulation protecting the cryogenic propellant to be practical.

To get around that, designers gave SLS a boost.


Next time: How the solid rocket boosters use aluminum – the same stuff you use to cover your leftovers – to provide enough thrust to get SLS off the ground.

Join in the conversation: Visit our Facebook page to comment on the post about this blog. We’d love to hear your feedback!

Time Flies: Next-Generation Rocket Is the Work of Generations

This week’s Rocketology post is by the newest member of the SLS communications team, Beverly Perry.

When NASA’s Space Launch System (SLS) first flies, it will slice through Earth’s atmosphere, unshackling itself from gravity, and soar toward the heavens in an amazing display of shock and awe. To meet the engineering challenges such an incredible endeavor presents, NASA’s Marshall Space Flight Center draws upon a vast and diverse array of engineering talent, expertise and enthusiasm that spans multiple disciplines and, in some cases, a generation. Or two.

Kathryn Crowe is a twenty-something aerospace engineer who tweets from her smartphone and calls herself a “purveyor of the future.” Hugh Brady, on the other hand, began his career at Marshall during the days of punch cards and gargantuan room-sized IBM mainframes with an entire 16 kilobytes (!) of memory.

Kathryn Crowe and Hugh Brady
While they’ve had very different experiences, Kathryn Crowe and Hugh Brady share a common excitement for their work on SLS.

But if you think these two don’t have much common ground on which to build a strong working foundation, well, think again. Although the two aerospace engineers may be separated by a couple generations, they speak of each other with mutual admiration, respect and enthusiasm. And like any relationship built on a solid foundation, there’s room for fun, too.

Even though Brady’s career spans 50-plus years at NASA, he’s anything but jaded, to hear Crowe tell it. “Hugh still seems to keep that original sense of excitement. I figure if he thinks I’m doing okay, then I must be doing okay since he’s seen almost our entire history as an agency. It’s nice to have him to help keep me straight,” says Crowe, who recently received NASA’s Space Flight Awareness Trailblazer Award, which recognizes those in the early stages of their career who demonstrate creative, innovative thinking in support of human spaceflight. “And, he always tries to bring a sense of humor to everything he does.”

“I’ve enjoyed being mentored by Kathryn,” jokes the seventy-something Brady, who admits to failing retirement (twice, so far) because he loves the space program and can’t stay away. (Also, he said, because he doesn’t care for television. But mostly it’s because he loves space exploration and working with young, talented engineers.)

Crowe and Brady have worked together evaluating design options and deciding on solutions to make the second configuration of SLS as flexible and adaptable as possible. This upgraded configuration – known as Block 1B – adds a more-powerful upper stage and will stand taller than the Saturn V. It could fly as early as the second launch of SLS, which will be the first crewed mission to venture into lunar orbit since Apollo. Block 1B also presents the opportunity to fly a co-manifested payload, or additional large payload in addition to the Orion crew capsule.

Illustration showing the Block 1B configuration of the rocket and 8.4 and 10 meter payload fairing options
The addition of an Exploration Upper Stage to SLS will make the rocket more powerful and open up new mission possibilities.

For Crowe, a self-described “shuttle baby,” working on a future configuration of SLS means the chance to look at the big picture. “I like to have a global view on things. For this particular rocket, we’ve made it as flexible as we can. We can complete missions that we don’t even know the requirements for yet!”

For Brady, “Things have a tendency to repeat.” While technology and solutions continue to improve, some of the challenges of spaceflight will always remain the same. When it comes to wrestling with the challenges of a co-manifested payload, Brady draws on his experience, but focuses on solutions that are tailored for SLS. It’s bringing lessons from the past into the present in order to find the best solution for future missions. “It’s drawing on what we’ve learned from the past but not necessarily repeating the past. We want the best solution for this vehicle,” he emphasizes.

Crowe says the experience and knowledge Brady brought to the table made all the difference when studying options for the SLS vehicle. “Hugh would say, ‘I think we worked on this particular technical problem when we were initially flying.’ He could draw parallels so we didn’t reinvent the wheel,” Crowe says. Since then, Brady has become something of a mentor to Crowe and other younger team members.

“When you put that kind of technical information on the table it gives people better information – information that’s based on prior experience,” Brady says. “We may not pick the same solution, because technology changes over time, but we will have more and better information to use when making decisions.”

“I think that having that kind of precedent to build upon it really is a beautiful thing,” Crowe says.

For his part, Brady says he feels a “comfort” level in passing the United States’ launch vehicle capabilities on to the next generation of engineers and other supporting personnel. “One of the things I find very exciting is to look around and see the young talent around the center with their energy and enthusiasm. I feel good thinking about when I do hang it up – again – that they will carry on and even do more than we did,” he says.

When you ask Crowe if humans will get to Mars, she says, “For sure I think within my lifetime I will see humans on Mars. I think more than ever right now is the right time to return to human spaceflight. We have the right skills and expertise. And when we successfully complete our mission and show that sort of hope to people again, that’s going to be equally as important as technological benefits.”

“That’s the objective,” Brady says. “I can’t wait until we fly again. It’s a tremendous feeling! It’s exhilarating! It’s time.”

https://www.youtube.com/watch?v=https://www.youtube.com/watch?v=gXMhOe1pRKc[/embedyt]If you do not see the video above, please make sure the URL at the top of the page reads http, not https.


Join in the conversation: Visit our Facebook page to comment on the post about this blog. We’d love to hear your feedback!

Making a Lot of Fire in Two “Easy” Steps

On one end of the technology spectrum, you have rocket science, mastering the laws of physics to allow human beings to break the chains of gravity and sail through the void of space.

On the other end, you have the earliest humans, first learning to use the world around them in innovative ways to do things they previously couldn’t.

What do these two extremes have in common? Making fire. Just like the secret to learning to cook food was mastering the creation of flames, creating fire is also the secret to leaving the planet.

We just use a much bigger fire.

Close-up of aft end of SLS during launch
Solid rocket motors and liquid-fuel engines will work together to propel the first SLS into space.

If you’ve watched the first video in our No Small Steps series you’ve learned why going to Mars is a very big challenge, and why meeting that challenge requires a very big rocket. In the second installment we talked about how NASA’s Space Launch System (SLS) builds on the foundation of the Saturn V and the space shuttle, and then uses that foundation to create a rocket that will accomplish things neither of them could.

Now, the third No Small Steps video takes a step further by looking at the basics of the monumental energy that makes the rocket go up. If you’ve been following this Rocketology blog and the No Small Steps videos, you’re aware that the initial configuration of SLS uses two different means of powering itself during launch – solid rocket boosters and liquid-fuel engines.

But why? What’s the difference between the two, and what role does each play during launch? Well, we’re glad you asked, because those are exactly the questions we answer in our latest video.

With more SLS engine and booster tests coming in the next few months, this video is a great way to get “fired up” about our next steps toward launch.

https://www.youtube.com/watch?v=http://youtu.be/zJXQQv9UZNg[/embedyt]
If you do not see the video above, please make sure the URL at the top of the page reads http, not https.


Join in the conversation: Visit our Facebook page to comment on the post about this blog. We’d love to hear your feedback!