From FGB-2 to MLM: Origin of the Nauka module
The MLM multi-purpose module (a.k.a. FGB-2 or 77KML No. 17901) originated as a backup copy to the first element of the International Space Station -- the Zarya control module, which was launched in November 1998.
An isolated view of the MLM module in deployed position. Copyright © 2012 Anatoly Zak
The evolution of the MLM's specifications:
A sibling of the first station piece
The first of two sibling spacecraft -- Zarya FGB control module -- was built during the 1990s by Moscow-based GKNPTs Khrunichev under a contract with the Boeing company. Although the agreement funded only a single vehicle, Khrunichev used available spare parts and its own funds to build a backup module, in case the original spacecraft was destroyed or rendered unusable in a launch accident.
By the time the original Zarya FGB-1 had docked successfully to the Zvezda service module in July 2000, its backup module was about 65 percent ready, according to GKNPTs Khrunichev. At that point, Russian space officials considered several potential new roles for the remaining spacecraft in the ISS program, including its use as a heavy supply ship for the Russian segment of the station.
In mid-2000, Boeing announced that it had partnered with Khrunichev to "commercialize" the FGB-2. The move put Khrunichev/Boeing team on a collision course with RKK Energia and Spacehab, who at the end of 1999 claimed the same docking port on the ISS (nadir or Earth-facing docking port on the Zarya module) for their commercial Enterprise module. In the end, none of the two projects had materialized.
A new role for FGB-2
Published: 2001 August 10
During 2001, in an effort to save money on the virtually stalled development of the Russian segment of the International Space Station, GKNPTs Khrunichev proposed to use the FGB-2 spacecraft as a base for the Universal Docking Module, USM. The USM would serve as a hub for up to three Russian research modules; however, work on the USM module all but stopped due to lack of funds.
The concept of using the FGB-2 as a Universal Docking Module had been considered in previous years, however the amount of work required for modifying the module for the task would have not justify the effort. For example, the transfer compartment on FGB-2 had to be repositioned and equipped with three additional docking ports to receive future science modules. However by 2001, Khrunichev officials argued that in light of the financial situation at the time, Russia had no chance of building any of its science modules during the station lifetime.
According to Khrunichev, it would be enough to add a single docking port to the FGB-2 in order for it to serve as the Universal Docking Module. In August 2001, Khrunichev and RKK Energia -- the main Russian contractor on the ISS -- reportedly agreed on the use of the FGB-2 as the Universal Docking Module.
According to that plan, the FGB-2 module would dock to the Earth-facing (nadir) port on the Zvezda service module, i.e. the same port where the UDM module was expected to reside. Such a configuration would leave the "nadir" port on the Zarya module for the RKK Energia's proposed Enterprise module.
In addition to the new docking port, the FGB-2's solar panels and a number of other systems would have to be modified, in order for the spacecraft to serve as a replacement for the UDM.
Khrunichev representatives said that the FGB-2 could be prepared for launch within two years after a decision on its mission had been made. From around 2001 and until 2004, the launch of the FGB-2 module to the ISS was scheduled for 2007.
Multipurpose Laboratory Module, MLM
Around 2004, it was proposed to convert the FGB-2 module into the Multi-Purpose Laboratory Module, MLM, or 77KML, according to its industrial designation. At the time, it was expected to dock the spacecraft to the nadir port of the Zarya FGB module. In order to have enough clearance during berthing with the Zarya, the front active docking port of the MLM was to be installed on a special extension adapter. According to the same plan, the MLM module would be followed to the ISS by a research module, which would be docked at the nadir port of the Zvezda Service Module. However this plan was eventually re-worked.
On July 31, 2006, the Federal space agency, Roskosmos issued a Decision No. AP-99 "On the clarification of the technical design and the work order of the multi-purpose module (MLM)."
On November 3, 2006, RKK Energia and the Russian space agency, Roskosmos, signed a contract calling for the development of the Multipurpose Laboratory Module, MLM. At the time, work on the module was expected to start in 2007, and its launch was targeted for 2009.
In the new configuration, the MLM module would accommodate service systems for the Russian Segment of the ISS and scientific payloads. The European-built ERA manipulator and the DMS-R multi-function computer would also be installed onboard. A special automated airlock for moving payloads from the interior of the station to the vacuum of space would be installed on the lower section of MLM.
To be delivered into space by the Proton rocket, the module would have an initial mass of 20,700 kilograms and provide 70 cubic meters of pressurized volume. Around eight cubic meters would be available for cargo storage and the same volume would be left for the installation of the scientific payloads. The module would sport a total of 12 workstations for various instruments and experiments. Special incubators and vibration-protected platforms for sensitive material-science research would be available.
Prior to the MLM launch, the Docking Compartment-1, which had occupied the nadir (Earth-facing) docking port of the Zvezda service module, was to be discarded along with a departing Progress cargo ship. It would then be directed to the Earth atmosphere to burn up. The MLM would then use its own engines to rendezvous with the station and dock to the freed nadir port on Zvezda.
Around a year or two after the MLM arrival at the station, a 4,000-kilogram ball-shaped Node Module would be docked to the outer end of the MLM, enabling the addition of as many as five spacecraft to the Russian segment of the ISS.
On November 9, 2007, the Collegium of the Federal space agency issued an order No. 22p "On the implementation of the Russian Segment program for the International space station in 2008-2015." The document called for a two-phase construction of the Russian Segment, where the first phase would be concluded with the addition and outfitting of the MLM module. The second phase would include the addition of the Node Module and the Science and Power Module, NEM.
By the beginning of 2008, the launch date of the MLM slipped from 2009 to 2011. Until May 2009, the MLM was promised to take off in December 2011. During the May 29 press-conference at the mission control in Korolev, Aleksei Krasnov, the head of manned space flight at Roskosmos said that launch was expected in the first quarter of 2012. However in the October 2009 NASA schedule, the mission was still marked for launch in December 2011.
In August 2011, the Director General of GKNPTs Khrunichev, Vladimir Nesterov, said that a prototype of the MLM module designed for electrical tests would be delivered to RKK Energia before the end of the month, despite technical issues associated with changes in the module's design documentation. (503) Around the same time, industry sources said that an integrated prototype of the MLM module had already been delivered to RKK Energia and was in process of being hooked up to the integrated prototype of the Russian segment.
By the Fall of 2011, the launch of the module was postponed from December 2012 to June 2013, as the earliest. By 2012, the launch slipped further to 2014.
Key contractors in the MLM module development:
The FGB-2 module, minus its solar panels, sits in the assembly shop at Khrunichev enterprise in Moscow in August 2001. Protective red boxes cover attitude control engines. Copyright © 2001 Anatoly Zak
The FGB-2's docking adapter in its original configuration. Additional docking ports would have to be installed on the section to adapt the module for the new role of the Universal Docking Module, UDM. By 2008, developers decided to add a special Node module to that section to enable further expansion of the Russian segment. Copyright © 2001 Anatoly Zak
The interior of the FGB-2 module viewed from the docking adapter section toward the front docking port. Copyright © 2001 Anatoly Zak