poutre Z1

CONT: [...] l'élément de structure Z1 [est une] pièce unique en son genre. Il s'agit d'un élément de structure externe à l'intérieur duquel se trouvent des gyroscopes et du matériel de télécommunication et qui servira plus tard de plate-forme de montage des immenses panneaux solaires qui alimenteront la Station spatiale internationale en électricité.
CONT: Z1 est une plate-forme de communication [qui] supporte des systèmes de communication en bande Ku et S. Le système en bande Ku permet une transmission de données à haut-débit vers le sol, à la vitesse de 50 Mbps Mégabits par secondes). C'est suffisant pour transmettre 4 signaux vidéo en même temps. Ce système servira donc pour la liaison télévisée, mais aussi pour le fret à bord.
OBS: poutre Z1; segment de poutre intégrée Z1; Z1; ITS-Z1 : termes et abréviations uniformisés par le Groupe de travail de la terminologie de la Station spatiale internationale (GTTSSI).

CONT: The first segment to be launched into orbit, designated Z1, will not permanently attach to other truss segments. The Z1 segment is a 10 ft (3 m) cubelike truss made from six machined bulkheads that are bolted together. The truss houses four control moment gyroscopes that form part of the guidance, navigation, and control system. The location of Z1 is nearly in the middle of the station, which makes it an ideal location for the gyroscopes. A micrometeor shield composed of three sheets of 0.25 in. (6 mm) aluminum about 5 in. (127 mm) apart protects the sensitive gyroscopes from debris. The 18,300 lb (8,300 kg) Z1 segment is currently scheduled to be launched by the end of this year. The truss is a transitional structure that will connect to the pressurized Unity module already on orbit. Astronauts will tighten 16 motorized bolts on the circular coupling on the Unity module side into nuts on Z1 and connect the associated utility plug-ins. Pressurized units generally have circular couplings and nonpressurized unit connectors are rectangular.
CONT: The Z1 truss segment is equipped with several spacewalk aids: Two EVA tool stowage devices (ETSDs), 22 worksite interface (WIF) sockets, 1 flight-releasable grapple fixture (FRGF), 11 trusses, 2 tray launch restraints, numerous standard handholds and handrails, and several custom handles.
OBS: The first piece of truss structure - we refer to it as the Z1 Truss because it is the zenith or uppermost - will be on the uppermost part of the station or the top; the zenith.