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!

 

Getting a good look at the terminator

The first images from NASA’s Lunar Reconnaissance Orbiter, or LRO, are in. The images were taken along the moon’s terminator — that’s the dividing line between day and night — giving scientists a good look at the topography. It’s exciting times for the LRO scientists and the folks at NASA’s Constellation program because the close-up camera shots will help determine safe landing sites for future explorers, locate potential resources, describe the moon’s radiation environment and demonstrate new technologies. It means NASA is another step closer to returning humans to the moon.

The satellite also has started to activate its six other instruments. The Lunar Exploration Neutron Detector will look for regions with enriched hydrogen that potentially could have water ice deposits. The Cosmic Ray Telescope for the Effects of Radiation is designed to measure the moon’s radiation environment. Both were activated on June 19 and are functioning normally.

 

Instruments expected to be activated during the next week and calibrated are the Lunar Orbiter Laser Altimeter, designed to build 3-D topographic maps of the moon’s landscape; the Diviner Lunar Radiometer Experiment, which will make temperature maps of the lunar surface; and the Miniature Radio Frequency, or Mini-RF, an experimental radar and radio transmitter that will search for subsurface ice and create detailed images of permanently-shaded craters.

 

The final instrument, the Lyman Alpha Mapping Project, will be activated after the other instruments have completed their calibrations, allowing more time for residual contaminants from the manufacture and launch of LRO to escape into the vacuum of space.

This instrument is an ultraviolet-light imager that will use starlight to search for surface ice. It will take pictures of the permanently-shaded areas in deep craters at the lunar poles.

 

Can’t wait to see and learn more.

 

All eyes on LRO

Constellation has its eyes on the Lunar Reconnaissance Orbiter and is anticipating some great images. The spacecraft entered lunar orbit on the morning of June 23 and after that orbit is refined engineers will power up and calibrate LRO’s instruments. In a couple months, LRO will begin mapping the lunar surface to find future landing sites and searching for resources that would make possible a permanent human presence on the moon.

 

While the Apollo missions demonstrated that that it was possible to send humans to the moon, they did so for very short times – only three days, and at great risks. The LRO mission is paving the way for extended human habitation on the lunar surface and striving to reduce the risks to the astronauts travelling there.

 

LRO’s very high resolution cameras and laser altimeter will examine more than 50 potential landing and outpost sites on the lunar surface in enough detail to resolve an object the size of a beach ball. This will provide information to engineers currently designing the Altair lunar lander and allow them to build safe and effective landing systems, and will give mission planners the information they need to select safe landing sites.

 

Plus, the logistics resupply of a lunar outpost will be a challenge far exceeding that of the International Space Station. It will be necessary for lunar astronauts to learn to “live off the land” by utilizing the resources available on the moon. These may include water in permanently shadowed regions of the lunar poles, which could be invaluable for both consumables for the astronauts and propellant for their spacecraft. LRO instruments will map these regions of shadow and determine whether and where these resources are located. In addition, LRO will map the resources of the entire moon’s surface looking for deposits of other valuable resources, such as oxygen, locked in the lunar soil.

 

The availability of energy also will be the determining factor on how effective humans will be in accomplishing lunar science and exploration objectives. Because the moon’s axis is not tilted like the Earth’s, there are regions of the lunar poles that receive almost continuous sunlight, rather than the 28-day cycle of light and dark found in most regions. This will allow solar power systems to provide electricity to a lunar outpost with much greater efficiency. The LRO cameras will accurately determine these regions of perpetual sunlight by observing them over an entire year. 

 

See the LRO web site for additional info: http://lro.gsfc.nasa.gov/

Augustine Panel Video

We’ve received several requests for the video that was presented yesterday at the Augustine Panel meeting. It’s called “Constellation: Launching a Program” and you can click on the image below the view the video. You can also access it by visiting the Constellation page at https://www.nasa.gov/constellation and select “Multimedia” on the left menu. You can also copy the following code to embed the video from the NASA Telvision YouTube site:

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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/

Come Checkout Constellation on the Move in Las Cruces,N.M.

A mockup of NASA’s nearly 45-foot long launch abort system (LAS) for the crew exploration vehicle, Orion, will be on display from 5 p.m. – 8 p.m. CDT on Thursday, June 18 at New Mexico State University’s “horseshoe” area.

 

The Orion launch abort system on display in Nashville, TN. 

 

The system is being used to help NASA engineers prepare for the Pad Abort 1 test, which will take place in nearby White Sands Missile Range in November. When astronauts launch to the moon aboard the Orion crew exploration vehicle, the LAS will pull the crew and its module out of danger should a malfunction in the launch vehicle occur on the launch pad or during ascent atop the Ares I rocket. The 90-second Pad Abort 1 flight test will help gather information about how LAS operates in reality.

 

Other NASA exhibits include a large inflatable tent, handouts, a guest appearance by EVA, one of NASA’s inflatable astronauts, and models of its newest space vehicles, the Orion crew module and the Ares I and Ares V rockets. NASA’s Constellation Program is developing these vehicles, including the Altair lunar lander, to send humans to the International Space Station, moon and beyond after the shuttle retires in 2010.

 

A NASA inflatable tent exhibit on display in Austin, TX. 

 

Folks in the area are invited to catch a glimpse into NASA’s next steps in space exploration. We’ll have NASA employees there from Dryden Flight Research Center in California, Johnson Space Center in Texas, White Sands Test Facility and White Sands Missile Range in New Mexico. The public events are part of the Las Cruces community event held in conjunction with the June 19 groundbreaking of Spaceport America, the world’s first purpose-built commercial spaceport.

 

For more information about NASA’s next steps in space exploration, visit: https://www.nasa.gov/constellation. 

 

Orion Crew Modules from Coast to Coast

Here’s a look at just a few of the crew modules being developed around the country for Constellation’s Orion crew exploration vehicle.

Orion PA-1 flight test crew module at Dryden

Surrounded by work platforms at NASA’s Dryden Flight Research Center, the full-scale Orion crew module is undergoing preparations for the first flight test of Orion’s launch abort system, called Pad Abort 1 (PA-1), targeted for November at White Sands Missile Range, N.M. The test module has recently completed a series of high-intensity acoustic tests, simulating the noise made by the launch abort system motors, to evaluate how high frequency vibrations could affect the module’s structure or its electronics. Image credit: NASA/Tony Landis

 

The boilerplate Orion crew module for the PA-1 flight test is tilted on jacks during weight and balance testing at NASA Dryden in late 2008. This module is now at White Sands Missile Range, N.M. to help teams prepare for PA-1. Image credit: NASA/Tony Landis

 

Orion crew module at KSC

In the Operations and Checkout Building’s high bay at NASA Kennedy Space Center, Fla. technicians finished installing panels on the crew module mockup that simulate the spacecraft structure. The Orion crew module mockup at KSC is paving the way for Orion’s flights into space as teams simulate work to be done in the manufacturing and assembly processes. Image Credit: NASA/Kim Shiflett

 

Orion ground test article at Michoud

Orion prime contractor, Lockheed Martin, continues construction of the ground test article at the NASA Michoud Assembly Facility in New Orleans, La. This ground test article will serve as a production pathfinder to validate the flight vehicle production processes and tools. When completed, the module will be tested on the ground in flight-like environments, including static vibration, acoustics and water landing loads.  Image Credit: Lockheed Martin

 

Post-landing Orion Recovery Test crew module at KSC

After completing its at-sea testing in the Atlantic Ocean, the Post-landing Orion Recovery Test (PORT) module is at KSC awaiting preparations for the next step. The next round of tests involve installing seats and simulated hardware inside the module for astronauts to practice getting out while in a wave-simulating pool in Aberdeen, Md. Image Credit: NASA

 

Orion Exploration Development Lab crew module

Lockheed Martin engineers sit inside a full-scale, low fidelity mockup at the Exploration Development Lab in Houston where engineers and astronauts work together on human factors studies such as vehicle fit, form and function as well as emergency ingress and egress exercises. Image Credit: Lockheed Martin

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