Tim Furniss/KENNEDY SPACE CENTER
With six International Space Station (ISS) assembly missions scheduled for 1999, and 18 more due to take place between 2000 and 2002, NASA's Space Station Processing Facility (SSPF) at the Kennedy Space Center, Florida, is soon going to be a hive of activity.
The Photovoltaic Module P6 Integrated Equipment Assembly (IEA) for the ISS arrived in Florida on 12 January. The 4.8m-long, 7,640kg, IEA joins the Node 1 and Pressurised Mating Adaptors (PMAs) 1 and 2 at the SSPF. The Node 1 and the PMAs are scheduled to be launched on the first US assembly mission for the ISS, the STS88/Endeavour in July, while the IEA is due to be launched in April 1999.
The Node will provide access to other ISS elements which will be connected eventually to six PMAs. The PMA 1 will be the docking port for the Russian Control Module, to be launched on the first ISS mission aboard a Russian Proton booster in June (Flight International, 28 January-3 February). The Shuttle's remote-manipulator-system robot arm will grapple the Control Module and draw it into the PMA 1's port.
The PMA 2 will provide future Shuttles with a docking port. Later PMAs will support the attachment of an airlock, cupola, mini-pressurised logistics modules and the US laboratory and habitation modules.
The IEA, which will accommodate one of several planned sets of solar arrays, power-storage batteries, power-control units and a thermal-control system, will be launched on the fourth NASA assembly mission, the STS97/ Discovery in April 1999 (Flight International, 11-17 June, 1997). Preparations for the intervening ISS missions are also being made in the SSPF. The STS96/Endeavour mission, due for launch in December, will be a logistics flight using a Spacehab Double Module which will not arrive at the SSPF until October after a non-ISS mission in 1998. Work on the STS97/Discovery mission payloads, including the Z1 truss, to be launched in January 1999, will begin this month.
"Our job basically is to make sure everything fits," says Mary Poulin, NASA customer-support manager for the SSPF. Poulin works with payload contractors, as well as ISS prime contractor Boeing. The SSPF was designed for the ultimate user by the former McDonnell Douglas Space Systems (now part of Boeing).
Poulin says that the SSPF will also support payloads for some of the other non-ISS Shuttle missions scheduled in this period. "The first payload processed in the SSPF when it was opened in 1994 was the Docking Module," she adds. This was linked to the Mir space station in 1995, to support further Space Shuttle Mir missions. Other processed payloads include pallet-mounted payloads for Shuttle missions.
FLOW SCHEDULES
Processing flow schedules have already been produced for the SSPF, allocating each mission's payload one of the eight "cells" or "footprints" in the high bay at Kennedy. An SSPF team has produced a 1998 "time-slice" programme, which consists of a two-dimensional computer-generated plan and isometric layouts of how the SSPF will be laid out each month, showing the location of every piece of equipment during the year's ISS payload processing programme.
Each of the eight footprints' Launch Package Integration Stands can be moved on air-bearing supports on the floor. Each footprint is equipped with services such as electricity and air conditioning through stub-ups on the floor.
An intermediate bay will be used to process payloads for utilisation missions, such as payload racks to be fitted into the Italian Mini-Pressurised Logistics Module, due for a 1999 launch.
The processing team in the SSPF consists of NASA and Boeing payload managers. The former McDonnell Douglas was contractor for the Payload Ground Operations work, with Boeing as the Space Station prime contractor. NASA provides a customer-services responsibility to Boeing and to contractors for international payloads such as the Japanese Experiment Module.
The Node 1/PMA processing schedule to support the first mission in June is typical of the SSPF's work. This consists of:
acceptance testing; cargo-element integration test; communications end-to-end test with mission control; air-leak check; installation of survey and optical targets; toxicology test, where samples of air inside the Node will be collected; payload/orbiter interface verification test, carried out on the launch pad after the completed payload has been delivered in a canister from the SSPF to the payload change-out room.The SSPF is also engaged in post-mission processing of returned payloads, which means a doubly difficult planning job to meet the ISS assembly schedule.
Source: Flight International
