Strela (crane)

Strela (Russian Стрела for arrow or swing arm ) denotes two cranes of Russian design at the International Space Station ( ISS).


The Strela crane system is based on a similar crane the Russian space station Mir. The two identical cranes used on the ISS are designated according to the boot sequence as Strela -1 and Strela -2. In contrast to the robotic arm Canadarm2 and the planned European Robotic Arm already installed on the ISS, the Strela cranes provide far less complex systems dar. Thus, the movements of the crane arms on EVA operations are controlled directly by a spaceman by hand. A remote control of cranes, such as the interior of the station is not possible. In addition, the cranes are not able to independently perform robotic actions. Both cranes were initially mounted on mounting points near the exit gate of the Russian Pirs module and not intended to operate from other positions on the outer skin of the ISS. To prepare for the replacement of Pirs by the new research module Nauka in 2013, an outdoor intervention took place on 16 February 2012. With Strela -2 cosmonauts Oleg Kononenko and Anton Shkaplerov Strela -1 shifted to the opposite largely identical module Poisk. The next spacewalk to transfer the cranes took place with Gennady Padalka and Yuri Malenchenko on 20 August 2012. With Strela - 1 of Poisk offset from the two cosmonauts Strela -2 to the new location on the spherical coupling node Sarjas.

Start and Installation

Strela -1 was not delivered as a finished crane into orbit, but transported in pieces aboard two Space Shuttle and assembled in space. The first components of Strela came as part of the Space Shuttle mission STS -96 on the mounted in the payload bay Integrated Cargo Carrier ( ICC) to the ISS. On 30 May 1999, the base with a control unit and accessories in a nearly eight hours of lasting spacewalk was temporarily attached to the Russian segment. The next time you visit a Space Shuttle (STS -101) was supplied for Strela and also tentatively fixed on the coupling adapter PMA -1 in assembly work under a spacewalk in the payload bay of Atlantis the extension arm ( Main boom ). After the automatic docking of Pirs in September 2001, the already existing components of Strela -1 at a spacewalk of Expedition 3 were spent on 8 October at its permanent location near the exit hatch of the Pirs and assembled there. A test of the function and stability of the crane arm had to be omitted due to time constraints, however, initially. In a spacewalk on November 12, the assembly was completed and first motion tests performed. Since then Strela was ready to Pirs and served as a support astronaut at almost every begun by Pirs spacewalk.

Pirs himself led at the start in the interior with the components of Strela -2. As part of the spacewalk of Expedition 4 on 14 January 2002, the stand and the boom were spent by the exit airlock into space and mounted opposite of Strela -1 on the outer skin of Pirs. In addition, accessories are such as bringing a payload transport container for the Strela system into space and prepared for use.


The main task of the Strela cranes is to support astronauts during spacewalks, particularly in construction and maintenance of the space station. Mostly the cranes come in spacewalks, emanating from the Russian Pirs airlock at or Poisk, used. Among the equipment includes among other things a Kranarmverlängerung, with the radius of action when necessary can be expanded to about 4.6 meters, and a transport container for loading of payloads as well as a working platform stand support with the help of which the astronauts can attach to the end of the crane boom. By means of the extension of the crane system will be able to reach almost any point on the segment of the Russian ISS.

In addition to transporting smaller station components and outboard experiments Strela is used to bring the astronauts themselves to their destinations. Through several mounted on the crane boom handles the astronauts during spacewalks can move much faster on the Russian segment or can be transported using the work platform directly to the respective location. This saves valuable time during deployments, enabling more complex work in the mean duration of the spacesuits.

Sun, 15 Strela -2 crane including extension to install multiple meteorite shields ( Service Module Debris Panels) was used at the Zvezda module, for example, at an exit of the ISS Expedition. This 2.5 inch-thick aluminum plates were taken with the help of Strela the storage structure of the module PMA -3 and transported to the installation site. Even in zero gravity, such tasks can be carried out only partially by hand.


  • Stand Strela -1 with control unit (supplied with STS -96 on May 27, 1999)
  • Astronauts work platform (supplied with STS -96 on May 27, 1999)
  • Teleskopauslegearm Strela -1, 13.7 meters long (supplied with the STS -101 on May 19, 2000)
  • Extension, 4.6 meters long (supplied with the STS -101 on May 19, 2000)
  • Stand Strela -2 with control unit (supplied with Pirs on September 14, 2001)
  • Teleskopauslegearm Strela -2, 13.7 meters long (supplied with Pirs on September 14, 2001)
  • Transport container (supplied with Pirs on September 14, 2001)