Ares – Constellation

Ares DM-I Motor Test Turns Sand to Glass

SHAZAM!!! Like a mighty bolt of lightning, NASA’s new Ares I rocket first stage motor will be tested later this month sending a plume of fire reaching temperatures more than 3300 degrees Fahrenheit and smoke hurdling for hundreds of yards.

The five-segment solid rocket development motor, or DM-1, will be tested at Alliant Techsystem’s (ATK) test stand in Promontory, Utah on August 27. An interesting byproduct of the test is a unique geographical change that will take place when 50 cubic yards of sand is transformed into a shimmering glass field.

The heritage of shuttle motor testing can be seen in the foreground with a glass field,
created assand used to protect the test stand was heated to temperatures more
than 3,300 degrees Fahrenheit. In the distance, preparations for the first ground
test of the Ares I Development Motor 1 (DM-1) have begun at ATK’s facility
in Promontory, Utah. (ATK)

The art of glass making has been around for centuries. No one knows exactly when or where glass was first made. Evidence shows that it may have originated in Mesopotamia, where pieces of glass have been found, believed to date from the third millennium BC.
When Googling the term “making glass” on the Internet you will learn the process involves basic materials like sand, soda and lime. It also requires very high heat in excess of about 2,912 degrees Fahrenheit.

But engineers at NASA and ATK will use a slightly different method when they conduct the first full-scale, full-duration test firing of the first stage motor for the Ares I rocket.

Four dump truck loads of sand are placed over the aft end of the test stand as a thermal protection barrier to the concrete pad. The intense temperatures escaping the motor at Mach 3, penetrate the sand six inches deep, as the result, a glass field is formed in the wake of the plume.

“The glass has a green tint to it based on the minerals that are in the sand,” said Kevin Rees, director of test and research services at ATK Space Systems. “It eventually crumbles and erodes as it is exposed to weather elements, but right after a test it is fun to see the glimmer reflecting off the glass that was sand a few minutes before.”

So the next time you see a test of a solid rocket motor, you’ll know that this ultimate “high temp” oven is doing more than just paving the path for America’s future in space.

For more information about the Ares rockets or to watch the DM-1 hot fire test live, visit:

https://www.nasa.gov/ares

Bolting Down 3.6 Million Pounds of Thrust

The solid rocket is armed, the countdown is in its final minutes as NASA and ATK prepare to ignite Ares I five-segment first stage designed to take humans out of Earth’s gravitational pull — this time; however, the rocket isn’t going anywhere.

Engineers at ATK install new mid-span to support Ares I solid rocket motor design. (ATK)

The Ares I development motor, or DM-1, will be tested at Alliant Techsystem’s (ATK) test stand in Promontory, Utah on August 27. With a magnificent flash of light the 154-foot solid rocket motor will come to life, producing heat two-thirds the temperature of the sun and 3.6 million pounds of thrust from its 12-foot diameter cylinder.

Spectators will first see the flame of the motor, so bright the majority will wear sunglasses, then a few seconds later the sound wave will be heard, followed by the ground shaking. Those in attendance will gain a true understanding of the power produced by this motor.

Called by some an “engineering masterpiece,” the first stage is capable of producing 22 million horsepower which is equivalent to the energy produced by 25,882 race cars. So how do ATK and NASA hold down one of the world’s most powerful rockets?

The load measurement system on ATK’s test stand which is attached to the thrust block. (ATK)

“It’s comparable to an ice berg or an upside down mushroom where the majority of this massive test stand is underground,” said Gary Bates, chief test engineer for ATK Space Systems. “This motor is designed to go places, so we need to ensure that it can’t.”

The test stand is made out of 7,000 cubic yards of concrete, 308 tons of reinforced steel and 230 tons of steel plates and rails. It includes a 16-foot tall by 40- foot long, and 20-feet wide above ground concrete fixture, or thrust block, which is attached to an extremely large buried foundation measuring more than 100 feet long by 80 foot wide and almost two-stories below the ground.

The test stand also includes a new, mid-span support which was installed to support the weight of the longer five-segment motor for approximately 70 seconds until enough propellant has been consumed to lighten the weight of the motor.

Newly installed mid-span support for the Ares I five-segment solid rocket motor. (ATK)

The rocket is installed horizontally with attachments at the front and aft ends of the stand. More than a hundred fasteners up to 2.5 inches in diameter help hold the motor in place. At the thrust block, the first stage is attached to a load measurement system. This system is designed to not only handle up to 4.3 million pounds of force, but measure it.

“Along with securing the motor in the test stand, we need to be able to collect data during its operation,” said Bates. “This data is vital in understanding how the motor performs to compare with flight and other ground test data.”

Once the test is complete, NASA and ATK will be able to use the information in collaboration with data collected from the Ares I-X test flight this fall, to finalize the design of Ares I first stage.

For more information about the Ares rockets or to watch the DM-1 hot fire test live, visit:

https://www.nasa.gov/ares

A Process of Assessment

There have been recent reports containing a leaked preliminary internal Air Force assessment document regarding potential abort scenarios for the Ares I rocket and the effect on an Orion crew exploration vehicle. The assessment, as preliminary, addressed a certain class of abort scenarios. This class of aborts involves destruction of the first stage because of either a case over-pressure or because of a range safety initiated destruct command. The majority of aborts do not fall into this category because of the abort criteria and flight rules the program is implementing. The analysis is not an official Air Force position, but a starting point for working specific issues associated with the complexities of aborts.

An ongoing exchange of information and analysis is part of the formal process for the 45th Space Wing to evaluate a new vehicle’s request to use the Eastern Range and establish an operations agreement. NASA and the Air Force work together through routine technical interchange meetings to share data and analysis on launch vehicles and payloads. This is typical of how the two organizations have worked together in the past to evaluate Apollo, space shuttle, and nuclear payload missions such as New Horizons as they were in development. A joint team, comprised of experts from both NASA and the Air Force, meets routinely to collaborate on issues related to range safety, and works to provide answers to all outstanding questions and concerns.

The program will continue to work closely with the 45th Space Wing to mature the analyses as the development of the vehicle continues, with the top priority being the ability to protect the crew and public. ‪Ares/Orion were conceived and are being designed as the safest launch vehicles in history. The findings in this preliminary Air Force analysis have provided insight into the abort environment, and each issue and concern will be answered as NASA shares more in-depth studies and analysis with the Air Force and continues to refine its models and data. Constellation is a developing program and NASA will continue to work with the Air Force as the two agencies collaborate to assure both crew and public safety.‪

NASA Gives Official 'Go' for August 25 Ares I First Stage Motor Test

NASA gave the official “go” for the Ares I first stage Development Motor 1 (DM-1) test targeted for August 25 concluding a two-day test readiness review. Nineteen NASA managers signed off on the official readiness statement. It reads: “Pending satisfactory completion of normal operations flow and open items identified in this review, the Ares I First Stage test hardware is ready to support the static testing of DM-1.”

The review was held at ATK Launch Systems Huntsville, Al. office on July 21-22. More than 50 solid rocket motor technical experts reviewed every detail of the DM-1 solid rocket motor, now installed in a test stand at ATK’s Promontory, Utah test facility. The first stage five-segment development motor has been under development since 2006. It is based on the design of the space shuttle’s four-segment configuration, but includes several modifications.

Max Tavoian, ATK Space Systems manager opened the formal review for ATK. Tavoian noted that most people in the room had been working toward DM-1 for the last three and a half years.

“This review will tell you why DM-1 is ready to go. DM-1 has 46 design objectives and 650 instrumentation channels. This test will prove out a series of technology improvements and design attributes including changes to the propellant grain, nozzle and updated liner and insulation implemented by ATK related to the new five-segment reusable solid rocket motor.”

Over the two days, the team engaged in a healthy and thorough discussion about the motor’s instrumentation, propellant and motor performance, insulation and components, metal case components and seals, and the overall readiness to “go” for test on August 25. The upcoming test is expected to provide valuable data on motor internal pressures, thrust profile, and performance of new designs on the nozzle and the internal motor insulation. Additional benefits include data on roll-control, acoustics and vibration data. Engineers need all of this data to continue to design the Ares I rocket.

No issues emerged from the review that impact test readiness. Final instrumentation will be installed over the next month in preparation for the firing.

Alex Priskos, first stage manager for the Ares Projects Office at NASA’s Marshall Space Flight Center in Huntsville, Ala. chaired NASA’s test readiness review panel. He closed the meeting enthusiastically, acknowledging the hard work of the team which made this successful review possible. “This effort has been a thorough and professional effort. The professionalism of this team gives me a high level of confidence as we go forward with this test,” he said.

“DM-1 is about taking advantage of all we’ve learned from the Shuttle program — the safety aspects and technology enhancements — and moving forward to the next stage of crewed exploration beyond low-Earth orbit,” explained Priskos. “This test is the first step in a series of development and qualification tests. The ultimate goal is to design and build a first-stage motor that increases performance, is safe, reliable and will meet or exceed all of our requirements and objectives. The entire Ares team is looking forward to the DM-1firing next month and reviewing the test results.”

Jennifer Morcone, MSFC PAO

Ares I-X: Let the Stacking Begin…

Stacking is set to begin for the Ares I-X vehicle on Wednesday, July 8 in the Vehicle Assembly Building at Kennedy Space Center. It’s been a long time since the workers in the VAB have seen a new vehicle. In fact, it’s been 25 years since a new vehicle was stacked.

Following nearly three years of work by thousands of dedicated team members, the Ares I-X vehicle is ready for stacking on the Mobile Launch Platform, or MLP, in the Vehicle Assembly Building at Kennedy Space Center.

Over the last week, the management team has met for reviews. Today (July 7), a “go” was given for the stacking operations. All of the modification work has been completed in VAB High Bay 3, as well as the Mobile Launch Platform, in preparation for the new Ares I-X vehicle.

Tomorrow, the Ares I-X aft assembly, composed of the aft skirt and aft motor segment, will be rolled from the Rotation Processing and Surge Facility to the VAB and lifted by overhead crane and placed on the MLP. (Be sure to check out the KSC gallery for photo updates.)

Over the next month, the stacking operations will continue with the additional motor segments, simulated upper stage segments and the vehicle will be completed when the simulated crew module and launch abort system is added to the top. (There will be a time-lapse camera. NASA will be posting video and images.)

We will keep you posted on this blog, on our Facebook page and Twitter.

Let the stacking begin!

Comprehensive Constellation Status Report Presented to the Augustine Panel

The Norm Augustine led U.S. Human Space Flight Plans Committee heard from Doug Cooke and Jeff Hanley yesterday during the panel’s first public meeting held at the Carnegie Institute in Washington.

The full presentation, which includes a comprehensive status report on Constellation can be found at:

https://www.nasa.gov/exploration/library/hsfr_exploration.html

Jeff Hanley briefed that NASA is on track to maintain the March 2015 goal for the first crewed Orion/Ares flight to the International Space Station. He emphasized how Constellation is making use of existing NASA and contractor facilities and capabilities but in a leaner, smaller more sustainable manner to not just provide crew transport to space station, but to develop future human spaceflight systems that move beyond low Earth orbit, to the moon and beyond.

Technical progress to date is impressive. Scan through the Augustine panel briefing charts and you can see the labor of over 10,000 civil servant and contractor employees hard at work designing, building and testing hardware. Click and scan through an interactive tool posted to the Constellation website this week and you can see the Ares and Ares I-X, Orion, Altair vehicle designs come to life, linking design drawings to video footage of actual hardware and tests.

https://www.nasa.gov/externalflash/constellation_projects/

Dual-Plane Isolators Emerge as Most Promising Thrust Oscillation Fix

Engineers and rocket scientists love data. So no surprise the NASA thrust oscillation mitigation team has been gathering reams of data to best understand how to design an integrated vehicle that avoids thrust oscillation. This week at Ames Research Center, Moffett Field, Calif. NASA and industry engineers reviewed the latest progress to qualify and validate our understanding of thrust oscillation problems and solutions.

For those new to this issue, thrust oscillation is a phenomenon that can appear in all solid rockets where pressure created during launch conditions creates an up-and-down vibration at a frequency that could impact crew situational awareness or health. For Ares I, engineers expect a smooth ride up from liftoff to 115 seconds, but as the first stage nears burnout, thrust oscillations could pose a problem for a few seconds impairing the crew’s ability to read displays and respond to what they see.

Since the previous technical interchange meeting (https://blogs.nasa.gov/cm/blog/Constellation.blog/posts/post_1239311627391.html) several things have changed. Orion and Ares designs have matured and very helpful measurements have been captured during liftoff of the STS-126, STS-119 and STS-125 space shuttle missions which validate assumptions about how the solid rocket pressure oscillations occur in-flight. Mathematical modelers have an improved understanding of vehicle responses to candidate hardware designs. And finally, with the conclusion of the crew situational awareness testing, a new requirement has been proposed based on that work.

Constellation engineers have been pouring over new data to pinpoint several important factors that will drive optimal thrust oscillation fixes.

First, two important numbers to keep in mind: 12.3 Hz and .7g.

The thrust oscillation frequency of Ares I five-segment solid rocket motor is predicted to be approx. 12.3 Hz. By comparison, the shuttle’s four-segment solid rocket motor thrust oscillation frequency is 15 Hz. Ares I is a bit lower because it is longer. Think of an organ pipe: the longer the pipe, the lower the natural frequency. The goal of any mitigation is to minimize the effects on the crew due to the first stage thrust oscillation. There are two basic ways to do this: “de-tune” the vehicle stack or increase damping in the system. “De-tuning” is another way to say frequency separation — moving the natural frequencies of the Ares I vehicle and the Orion spacecraft away from 12.3 hz. Damping absorbs the extra energy in the system and can be targeted to specific frequencies. The goal of any mitigation system, or combination of systems, is to de-tune the vehicle approximately 1.5-2 Hz away from the vehicle’s natural resonance and avoid any problematic thrust oscillations with 99% certainty.

Since the Gemini era, NASA spacecraft designers used a limit of .25g peak as a safe threshold against these problematic longitudinal pressure oscillations. Based on increased fidelity gained through the crew situational awareness test series, the Constellation Program expects to set a new threshold, limiting the maximum peak to .7g, with a mean vibration level to not exceed .21g’s rms (root mean square) for any five second period during first stage flight.

Keeping these figures in mind, the team scrutinized proposed hardware solutions and how well each system, or combination of systems, will impact the integrated vehicle. Each thrust oscillation simulation includes over 10,000 analysis points including variations in forcing function, structural frequency response, and mode shape to provide an accurate assessment of how mitigation solutions will actually work in flight.

Design solutions under active development include passive single and multi-plane C-spring isolators, and mass absorbers called a Tuned Oscillation Array (or TOA). Work also continues on a LOX damper, which uses the slave mass of the Upper Stage liquid oxygen propellant to dampen out vibrations. Subscale hardware for two LOX damper designs — a bellows and diaphragm — have also been built and tested in the lab. All candidate solutions are being worked full force, and full steam ahead, to meet these updated parameters.

Initially, a dual plane C-spring isolator system was too heavy to incorporate into the overall vehicle design. The updated designs use titanium, not steel for the isolator springs, improving overall system performance while reducing the weight of the system. The weight reduction made a dual-plane C-spring isolator system much more attractive as a design solution and it is out-performing the other passive systems. The next step is to make a decision about how best to implement a dual plane solution into integrated designs. Nothing is off the table yet, as the team continues to refine which fix is most robust.

The team’s analysis during this session reemphasized that thrust oscillation is not just a first stage or Ares problem. It’s a technical challenge that impacts the entire vehicle and can be solved by an integrated team of Ares and Orion engineers. Because of this, final decisions about which solution is optimal will be incorporated as an issue into the Constellation Preliminary Design Review scheduled for late this year. The team also looks forward to capturing data from the upcoming five segment development motor test (DM-1) and Ares I-X flight which will further characterize how the in-line vehicle responds.

Reported by Jennifer Morcone, NASA MSFC public affairs