When NASA launches new projects, contractors and subcontractors contribute the manufacturing know-how to do the job faster, better, and cheaper.
The Lunar Prospector is fully assembled and seated atop the Trans Lunar injection stage, which detached from the spacecraft approximately an hour after launch.
The Lunar Prospector, now in a polar orbit 63 miles above the Moon's surface, will conduct studies of the Moon for one year. It is gathering information on the presence of water ice on the moon, as well as mapping out surface elements and magnetic fields.
The Lunar Prospector is a small graphite-epoxy drum, 4 feet in diameter and 4.5 feet high, with surface-mounted solar cells and three 8-foot masts which carry and isolate instruments from the main body of the spacecraft. The craft is spin-stabilized and controlled by six hydrazine monopropellant 22-Newton thrusters. Communications are through two S-band transponders and a slotted, phased-array medium gain antenna and omnidirectional low-gain antenna. Prospector has no on-board computer, so ground command is through a 3.6 kbps telemetry link. Six scientific instruments are mounted on its booms: a neutron spectrometer, a gamma-ray spectrometer, an alpha particle experiment, a magnetometer and electron reflectometer, and a Doppler gravity experiment. These instruments will carry out a detailed orbit investigation of the Moon to help scientists better understand its origin, evolution, current state, and resources.
The Lunar Prospector's instrument masts were stowed inside the shroud, or nosecap, of the launch vehicle for take-off.
A test at Lockheed Martin's Sunnyvale Facility shows the magnetometer/electron reflectometer at the end of a fully deployed boom.
Since the end of the Cold War, the National Aeronautics and Space Administration has strived to streamline operations and slash costs while putting the best available technology into space. Fortunately for NASA, it has found a goldmine of manufacturing expertise in its contractors and subcontractors that has been gleaned from years of aerospace work, most of which has been for NASA. To these companies, the space agency's new goal of "Faster, Better, Cheaper" is simply going about their everyday business.
Recently, NASA launched the Lunar Prospector, the third flight in its Discovery Program of low-cost, highly focused planetary science missions. The Discovery Program uses off-the-shelf technology as much as possible to put missions into space in three years or less. Although the Lunar Prospector will not land on the Moon, it is expected to precisely map its surface, supply information about its magnetic fields and gravity, and prove whether or not there is water on the Moon.
NASA spent roughly $63 million on the Prospector — actually quite a bargain compared to the billions spent on the Apollo program. According to the space agency, it spent $34 million developing the Prospector and another $4 million on operations. The launch vehicle itself was a mere $25 million.
NASA holds the spacecraft's 22-month development period up as a model of cooperation between private industry and government, a growing trend.
The cost-cutting strategy
NASA's first return to the Moon in 25 years was spearheaded by its prime contractor, Lockheed Martin Missiles and Space, Sunnyvale, Calif. According to Thomas Dougherty, project manager at Lockheed, the company was chosen from a field of 26 contractors. "NASA based that decision on the amount of top-notch science and technology it could get for the least amount of money. For Discovery projects, NASA fixes the amount of money at the start, and companies must live within that budget or run the risk of a canceled project."
Whether farmed out or in-house, the goal was to use as many off-the-shelf parts as possible and keep both purchased and manufactured part designs standard and interchangeable for future projects.
Lockheed engaged the businesses that supplied engineering, testing, machining, and production services as well as off-the-shelf products such as coatings and plumbings. The company's Buddy Nelson says the contractor had no shortage of firms with aerospace experience in the Silicon Valley. "And by subcontracting work out to these experts, Lockheed doesn't rack up enormous overhead costs," he adds.
In fact, Lockheed routinely outsources jobs. Dougherty explains: "Sunnyvale Lockheed does about $4 billion a year building spacecraft. The company has always outsourced at least 50% of its work, so the Lunar Prospector project was nothing new." The company simply stud-ied the Prospector's complete design and decided to make some components in-house, purchase some, and subcontract some out.
What was new for Lockheed was the level of involvement NASA had with the project. "The difference between the Discovery projects and others Lockheed has done for NASA is there wasn't the usual major involvement of government agencies in what is purchased, how it's purchased, and how it's designed or tested," reports Dougherty. "This is more of a hands-off approach. NASA says this is our goal and it's up to you and your expertise to get us there. Lockheed in turn uses the same approach with its subcontractors."
Dougherty says that manufacturing expertise is the most important factor in selecting a company. "Lockheed goes to a sub-contractor that's been building flight hardware for 20 years because it doesn't have to explain the job in regards to producing a quality product at the lowest possible cost."
Lockheed is now attempting to take the contractor/sub-contractor relationship to a higher level by fostering project partnerships.
A subcontractor's story
Lockheed subcontracted with Evans Precision Machining, Inc., Santa Clara, Calif., to manufacture hardware and subassembly parts for the Lunar Prospector. The parts, mostly internal to the craft, were close tolerance (±0.0002 in.) and made from aluminum, magnesium, and titanium. According to William Evans, president and owner, "Lockheed gave us the prints, told us what they expected as an end result, and let us do it." The company was then able to manufacture accurate parts within a specific timeframe, and at the lowest cost.
Part of the reason his company got the business, believes Evans, was a longstanding relationship dating back to 1980. "Back then, it was difficult to get work from Lockheed, and, besides, it wasn't sending much out," recalls Evans. Starting out on R&D projects with Lockheed, the company gained a reputation for producing quality work. As a result, Lockheed gradually farmed out more production work to Evans.
"Relationships evolve between large firms and the jobshops they outsource work to," says Evans. "These shops are given more and more responsibilities and soon gain expertise in doing their part of an overall manufacturing process." He believes a shop has to pay its dues and establish a reputation by providing high-quality work.
He attributes much of his company's success to the expertise of its journeyman machinists. The company, a 7,100 ft 2 facility, employs just 16 people, but approximately 70% of its shop-floor personnel are journeymen. The company "grows" its machinists on challenging aerospace work, and, over the years, its people have developed the skills and expertise to handle jobs where the blueprint sheets outweigh the part they're for. For example, with the Prospector project, parts were difficult, says Evans, and the volume was low, so "just setting up a machine" and running production was not an option. However, because of the skilled journeymen, the company didn't have to do expensive trial runs.
In addition to its personnel, the company also has a fair amount of muscle locked up in its machinery. Its milling department uses three computer-controlled 3- axis Kitamura vertical machining centers, two 3- axis Bridgeport mills, two Fagor-Shizuoka vertical machines, a horizontal Niigata pallet loader, and nine conventional vertical mills with 2-axis CNCs. Among the equipment found in its lathe department are a number of Hardinge DSM-59s and HLVs, a few Hardinge HNCs with barfeeds, a Bridgeport EZ Path, a Harrison 390, and an Ikegai gap lathe. To top it off, the company also has well-equipped finishing, inspection, and design departments.
Providing support to handle and hold
Another subcontractor that worked on the Lunar Prospector is C.L. Hann Industries Inc. This San Jose, Calif., R&D fabricating shop provided ground-support equipment to handle, hold, and manipulate the spacecraft for assembly and testing. The company also worked on the craft's bus frame, a carbon-fiber-based structure that could be considered the chassis. It is thin-walled and lightweight.
Normally, Lockheed would custom design frames for each project, but for this mission, it decided to use an existing design. Hann served as the integrator, modifying the frame to accept offthe-shelf components.
Hann employs 26 people in its 30,000 ft 2 facility. In the words of its vice president, Peter Hann, the company has become Lockheed's small sub-manufacturing arm at a controlled cost.
Over the past 15 years, the company has also become expert at choosing the right cutting tools for carbon-fiber material and handling the dust problem involved in machining the stuff. This expertise is important, feels Hann, as the aerospace industry increases its use of the material over standard aluminum.
The shop's greatest challenge with the Prospector was programming and manufacturing in a shorter-than-usual timeframe. Here the company excelled, cutting the delivery time from 26 to 13 months. An integrated CAD system linked to Lockheed was the key.
The company downloaded DXF files directly from Lockheed and reverse-engineered then built parts from numbers in the CAD file. Fortunately, Hann usually works with just CAD files and no prints, so this step was a snap.
Peter Hann says that Lock-heed's old engineering style is changing. Instead of trying to engineer a complete project, it stage engineers. Lockheed starts with a rough idea and discusses it with Hann. The shop processes material, develops raw subassemblies, and handles detail engineering at the plant to eliminate redundancy and slash cycle time. Hann believes that Lockheed has realized that maybe some manufacturing is better farmed out, freeing it to do what it does best — software and hardware engineering of spacecraft.
A booming success
The Prospector carries five instruments mounted on three masts, or booms, projecting from its sides. These booms were designed and manufactured by AEC-Able Engineering in Goletta, Calif.
Able also made the canisters that hold the masts and the flat interface plate at the mast ends for mounting instruments and holding the mast in while stowed for launch. This plate must be strong enough to hold down the masts while withstanding earth-shaking vibrations of actual launch. However, they must also disengage easily for mast release.
Three 8-ft long coilable masts are designed to deploy once the craft is in orbit. On each mast, there are three unidirectional fiberglass coils that provide the force for deployment. The coils also allow the masts to be stowed in 9-in.-diameter cylinders bolted to the spacecraft bus or frame.
At the center of the craft is a damper and control mechanism. This device initiates simultaneous mast deployment and keeps them from shooting out too fast due to centrifugal force, which could damage attached instruments.
Able engineered the entire mast system. Engineers calculated strengths and loads, designed, analyzed, built, and tested the system.
As a result of NASA's and Lock-heed's trust in Able's expertise and experience, the mast system now uses a mechanism that accepts off-the-shelf parts to synchronize mast or boom deployment. In fact, the Prospector uses one control mechanism to synchronize all three masts. This device is a reel that usually incorporates metal tape.
For the project, Able wrapped three metal tapes around the reel, one for each mast. With each reel revolution, the masts move out-ward the same amount.
To be faster, better, and cheaper, says chief designer Jeff Harvey, Able developed a novel damper system. The damper is in the reel center. It basically controls the energy being released from the coiled masts. Dampers were the off-the-shelf part that Able wanted to adapt to its reel.
Typically, qualified rotary dampers are used in this type of application. But with designing, analyzing, and building, their cost can be anywhere from $40,000 to $60,000. In comparison, an off-the-shelf version would cost about $2,000. Therefore, Able designed its reel for an off-the-shelf damper without having NASA nor Lockheed specifically saying how to do it.
Able ended up CNC machining a zigzag track around the inside of the reel. An arm with a little wheel that rides in the track controls mast release speed with a back-and-forth motion during deployment.
Documentation: No formal reporting
According to Jeff Harvey working on NASA projects usually meant subcontractors had to write extensive formal reports on every part.
For the Lunar Prospector project, Able did all the required and standard testing, but saved project time by not writing a formal report for NASA or Lockheed every step of the way. Able was trusted, says Harvey, because of its vast experience in the field. Plus, the company submitted a certificate of compliance stating that all NASA and Lockheed requirements were met.
Harvey notes that small, subcontracted companies can't afford the loss of reputation due to failures in their part of an aerospace project, so they usually do more testing than is needed. A Lockheed engineer did observe test procedures at Able, but there was no mountain of paperwork from documenting every test.
As a result of Able's work on this project, NASA has already asked it to submit a proposal for another Discovery project already in the works.
Instruments on board the Lunar Prospector
The Lunar Prospector is designed for a low polar orbit investigation of the Moon, including mapping of surface composition and possible deposits of polar ice, measurements of magnetic and gravity fields, and study of lunar outgassing events. The spacecraft will carry six experiments:
| Gamma Ray Spectrometer (GRS) |
The GRS will analyze gamma rays emitted by elements on the Moon surface. This information will help in the understanding of lunar evolution.
| Neutron Spectrometer (NS) and Alpha Particle Spectrometer (APS) |
Information from the NS should help scientists locate any significant quantities of water ice which may exist in the permanently shadowed areas near the lunar poles. The APS instrument will be used to find releases of radon gas on the lunar surface. This information could point to low-level volcanic/tectonic activity on the Moon.
| Doppler Gravity Experiment (DGE) |
Scientists hope that the Doppler method will provide information about the lunar gravity field and estimates of the surface and internal structure of the Moon.
| Magnetometer (MAG) and Electron Reflectometer (ER) |
The MAG/ER experiments will map weak lunar magnetic fields and their possible origins, such as meteor impacts. In addition, they should provide information on the size of the lunar core.
NASA's credo "Faster, Better, Cheaper" has fostered a number of projects in the Discovery Program.
The first project, called NEAR (Near Earth Asteroid Rendezvous), will be the first spacecraft to orbit an asteroid. NEAR is scheduled to make contact with asteroid 433 Eros on February 6, 1999.
The second Discovery mission is perhaps the best known. The Mars Pathfinder landed on the red planet on July 4, 1997, deploying a microrover called Sojourner to check out the Martian soil.
The Lunar Prospector, launched January of this year, is now in a polar orbit 63 miles above the Moon's surface.
The Prospector will conduct studies of the Moon for one year and should yield evidence about the Moon's origin and resources.
Stardust, NASA's fourth Discovery mission is slated to launch in early 1999. The spacecraft will gather dust grains between stars and collect samples of material surrounding an active comet.
The next Discovery mission has not been determined. However, NASA did narrow its search to five potential missions: Messenger (a Mercury orbiter), Vesat (a Venus orbiter), Aladdin (sample return from Martian moons Phobos and Deimos), Contour (a comet fly-by), and Genesis (solar wind sample return). Genesis and Contour have been selected.
Testing, testing, and more testing
The Lunar Prospector does not carry backup components, which would drive up weight and cost. Therefore, ground testing was the only way to ensure that a fully operational craft was ready to launch. When it came to testing expertise, Lockheed Martin teamed with Hewlett-Packard Company, Santa Clara, Calif., to develop a system for integrating and testing the spacecraft bus and payload. The HP technology helped Lockheed launch a rigorously tested spacecraft on a relatively small budget and within an aggressive schedule.
According to Mark Triolo, solutions specialist, HP had two functions in the project — testing and supporting functional electronics. Although it was a joint-engineering project with Lockheed, HP built the LPETS system.
Part of HP's strategy for developing the Lunar Prospector Electrical Test Set (LPETS) system quickly and inexpensively was using commercial, off-the-shelf components as much as possible and keeping software costs to a minimum. An added benefit of this strategy is that, with minor modifications, the system can be re-used on forthcoming NASA missions.
The LPETS was designed to do three things. First, it handled stimulus/response testing of spacecraft electronics. What this boils down to is scientists stimulate the spacecraft with a signal and look for an expected response. This simulates ground interaction, as an Earth station would send the craft signals. The scientists also simulated aspects specific to the internal workings of the craft, which are things it does on its own while in orbit — for example, keeping itself in a upright position.
Because NASA decided to cut costs by eliminating an on-board computer, the Lunar Prospector is not completely self-sufficient. The spacecraft just collects information and sends it to Earth. Ground personnel interpret this data, make a decision, and send a command back up. Hence, signaling is important and must work, because once in orbit, repairs aren't possible.
The second function of the HP system was solar array simulation. This meant supplying power in place of actual solar power. There was no sun in the assembly room.
The system's third function was keeping the on-board batteries charged until lift-off. On-board batteries provide backup power when the craft is out of sun-shot, on the dark side of the moon — again there is no solar power.
Lockheed initially looked at its normal processes for ways to cut costs and tighten schedules. One big area was electronics test. Lockheed worked with HP to reinvent this part of the process. Instead of doing everything in-house and on its own (specifying electronics test, producing a design, and building), the aerospace firm decided to get HP's help.
Triolo says that Lockheed realized that it was an expert spacecraft maker and HP was an expert in test. He believes that together the two companies produced a better product than either could have on its own. Interactive engineering is what he calls it.
Lockheed operated the test equipment, but HP did the front-end work — figuring out the design of the equipment, building it, then training Lockheed to use it. Triolo says that his company contributed to the Discovery mindset by standardization. HP provided a reusable, redeployable test system that was intentionally designed upfront. That way, Lockheed could use it for future NASA-type jobs. Previously, the present system would have been scrapped after the mission, and all parties would start anew.
Triolo comments that the Discovery program fostered positive attitudes among everyone involved. Subcontractors felt they had a hand in critical aspects of the project because both NASA and Lockheed let them choose the best means to an end. NASA didn't tell Lockheed how to change the spacecraft-building process, nor did Lockheed tell HP how to accomplish its part of the project.
Goals and outcomes were voiced, and each company involved was trusted to figure out how to achieve them. This gave subcontractors free rein to try new things. In the past, everyone would have been guided and told exactly what to do. With this new way of doing things, companies had more freedom to get the job done, but the project was still well organized.