June 2009 – Constellation

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:

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

Welcome to Our New Pad…

Check out the news release:

RELEASE: 09-127

NASA’S SHUTTLE PROGRAM HANDS OVER LAUNCH PAD TO CONSTELLATION

CAPE CANAVERAL, Fla. — The May 31 transfer of Launch Pad 39B at NASA’s Kennedy Space Center in Florida from the Space Shuttle Program to the Constellation Program is the next step in preparing the first flight test of the agency’s next-generation spacecraft and launch system. The Constellation Program is developing new spacecraft — including the Ares I and Ares V launch vehicles, the Orion crew capsule, and the Altair lunar lander — to carry humans to the International Space Station, the moon and beyond.

Since the late 1960s, pad B has been instrumental in human spaceflight programs, such as Apollo, Skylab and the space shuttle. The pad originally was built for the Saturn V rockets to launch the Apollo capsules to the moon. In July 1975, the pad was modified to support space shuttle operations. The first space shuttle to lift off from pad B was Challenger in January 1986.

The handover took place Sunday after space shuttle Endeavour was moved to Launch Pad 39A. The ground operations team will finish modifying pad B for the Ares I-X rocket launch. Modifications will include removing the orbiter access arm and a section of the gaseous oxygen vent arm and installing access platforms and a vehicle stabilization system.