Spacehab, which supplies the pressurised equipment-carrying module for the Space Shuttle, is working on a lightweight, unpressurised Integrated Cargo Carrier (ICC) unit designed to provide a commercial cargo service to the International Space Station (ISS).
The ICC will carry up to 5,400kg of cargo or hold external science equipment for the ISS, augmenting the single and double Spacehab modules, which are now being used to carry equipment and logistics to the Mir 1 space station.
The company has already awarded contracts to Germany's Daimler-Benz Aerospace (Dasa) and Russia's RSC Energia for the detailed design of the ICC.
RSC Energia will develop and produce the 3 x 4.5m Unpressurised Cargo Pallet (UCP) which bridges the Shuttle's payload bay above the tunnel leading from the Shuttle mid-deck to the Spacehab module. Dasa, a Spacehab shareholder, will design and produce the attachment hardware for the UCP and integrate the ICC into the Space Shuttle.
The ICC unit employs previously unusable volume in the Shuttle's payload bay, says Mike Lounge, a former Shuttle astronaut and now Spacehab vice-president of flight systems development. It will enable ISS supply and science experiments to be delivered on the same assembly missions simultaneously. While spacewalks will be required to unload ICC payloads, later versions could incorporate automated robotics to unload and transfer the cargo.
The Spacehab single modules have flown on four Shuttle missions over the past four years, carrying commercial and NASA-sponsored experiments, but the service was commercially disappointing.
A Spacehab single module was also used to support the third Shuttle Mir Mission (SMM), the STS76, in 1996, and the Spacehab double module was then introduced for the next five SMMs, also starting last year.
The Double module was flown on two SMMs this year, and another is due in September. The final SMM Double module flight will be the STS89 in 1998, after which there are no more firm bookings.
Use of the Spacehab Double module has proved invaluable for cargo-carrying on the SMM missions, and seems a logical choice for the ISS, but no contract has yet been signed. The ICC should strengthen Spacehab's case, although it will be competing with Italy's mini pressurised logistics modules, which are already manifested for ISS Shuttle missions 6A and UF 1, scheduled for June 1999 and January 2000.
The company has arranged up to $25 million financing to create the new ISS asset and to develop a special Spacehab Double module devoted to science, to be named the Science Double.
Should NASA sign a commercial service contract, ICC hardware production is expected to begin at the end of this year, with delivery to Spacehab's payload processing building at Cape Canaveral, Florida in mid-1999, in time to support the ISS Space Shuttle assembly mission 7A-1.
Source: Flight International