AEROSPACE INDUSTRY
UPDATE
May 2011
McIlvaine Company
TABLE OF CONTENTS
RUAG Space, Switzerland’s leading space company, recently brought into operation an additional 400 square meters of cleanroom facilities for the production of satellite instruments and electro-optical systems at its location in Zurich-Seebach. This brings the site’s total cleanroom area to almost 1,300 square meters (13,988 sq. ft.).
“We invested around three million Swiss francs in these new cleanrooms, which provide us with an excellent infrastructure for both current and future projects,” said Axel Deich, Head of RUAG Space Switzerland, during the official inauguration ceremony on Wednesday, February 9. “Our extremely demanding assignments in the fields of laser communication and scientific instruments for satellites will be the primary beneficiaries of this outlay,” he continued.
From start to finish, it took just seven months to build the superb facilities, which are located in what was formerly the site’s raw materials store. They are designed so that each stage of production – from parts assembly to measurements in the vacuum chamber – can be completed without the components ever having to leave the cleanrooms. There are only one or two such facilities in the world.
The Zurich-Seebach facilities comprise one ISO Class 8 cleanroom that covers approximately 100 square meters, one similar-sized ISO Class 6.5 cleanroom, and four ISO Class 5 cleanrooms each roughly 40 square meters in area. The Class 5 rooms boast a maximum permissible particle count of 100 particles per cubic foot. For the sake of comparison, a human being produces around 300,000 particles a minute when sitting down, and as many as three million when walking slowly.
Ultra-modern Technology – Low Energy Consumption
Held in place by more than ten thousand cable ties, fourteen kilometers of power and network cables run under the floors and through the walls to their respective terminals. A kilometer of small pipes made of highest-grade chromium steel are supplied with ultra-pure nitrogen from huge canisters in the basement. And 500 meters of vacuum cleaner hose carry all traces of dust out of the rooms through suction pipes in the walls and into massive containers in the basement.
The new cleanrooms are equally impressive when it comes to energy consumption. Potentially, the need to continuously circulate vast quantities of air could result in very high energy requirements. But the sophisticated ventilation system – the first of its kind in Switzerland, and the absolute state of the art on the international stage – reduces consumption to a minimum.
Indeed, if the cleanrooms were a private home, they would qualify for a certificate from MINERGIE, the Swiss energy efficiency association. Yet their low energy consumption in no way detracts from their performance. Even the very first measurements produced optimal readings for air pressure, humidity and temperature. The quality of the cleanrooms has, furthermore, been confirmed by the relevant authorities – the facility has already been validated and certified.
The Spacecraft Assembly Facility of NASA's Jet Propulsion Laboratory in Pasadena, Calif., was constructed in 1961 to support NASA's Ranger and Mariner missions to the moon, Venus and Mars.
America had entered the Space Age just three years earlier, with the launch of the JPL-built Explorer 1 spacecraft.
The Spacecraft Assembly Facility, also known as JPL Building 179, originally had just one high bay, the large chamber now named High Bay 1. It is about 80 feet by 120 feet (about 24 by 36 meters). In contrast to the cleanliness standards for spacecraft assembly today, in the early days of the facility, personnel were even permitted to smoke inside this high bay.
All JPL-built spacecraft through the Viking Orbiters (launched to Mars in 1975) were built in High Bay 1. At times during the 1960s, as many as five different spacecraft were being assembled at the same time in the facility.
After the original construction of the high bay, the System Test Complex on the south side of the high bay's windows was added. A second high bay, about 70 feet by 70 feet (21 meters by 21 meters) was finished in 1976 to support the Voyager Project. Spacecraft assembled in High Bay 2 have included Voyager 1 and 2, Galileo and Cassini.
The project being assembled and tested in High Bay 1 in spring 2011 is the Mars Science Laboratory, including its rover, Curiosity. The mission is scheduled for launch in November 2011. Mars rovers Spirit and Opportunity were also built in High Bay 1.
Emblems on the wall of High Bay 1 represent all the missions (spacecraft and instruments) that were assembled in the Spacecraft Assembly Facility, regardless of which high bay was used. These include the first successful missions to Venus, Mars, Jupiter, Saturn, Uranus and Neptune, as well as Earth's moon. The facility has also built Earth-science instruments, plus Wide Field and Planetary Cameras that flew on the Hubble Space Telescope.
Both of the high bays are certified to a cleanliness level of Class 10,000, which means that there are less than 10,000 particles of 0.5 micron (half a millionth of a meter or yard) or larger in size per cubic foot of air volume. It is a great place to work if you have allergies. The filtration systems in the high bays are effective in reducing both particulates as well as hydrocarbons. The system maintained acceptable levels even when a brush fire raged near JPL in 2009.
Personnel working in the high bay wear protective clothing to minimize particles and bacteria reaching the spacecraft and the facility. All the equipment that enters the high bay is cleaned first with approved solvents (usually isopropyl alcohol). Both high bays are equipped with continuous remote monitoring for environmental conditions and cleanliness levels to ensure system safety and quick response to anomalous conditions.
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