NASA Docking System

The NASA Docking System (NDS) is a spacecraft docking and berthing mechanism being developed for future US human spaceflight vehicles, such as the Orion Multi-Purpose Crew Vehicle and the Commercial Crew vehicles. The NDS is NASA’s implementation of the International Docking System Standard (IDSS), an attempt by the International Space Station Multilateral Coordination Board (MCB) to create an international spacecraft docking standard. The international Low Impact Docking System (iLIDS). is the precursor to the NDS. The NDS did not implement the "low impact" design goal of the iLIDS. The NDS Block 1, was designed and built by The Boeing Company in Houston TX, to meet the IDSS standards. It is currently (January 2017)being tested to complete it design qualification.

Two International Docking Adapters (IDA) will be attached to the ISS' Pressurized Mating Adapters (PMA), one at Node-2 forward, the other at Node-2 zenith. These will convert the Androgynous Peripheral Attach System-95 (APAS-95) to the NASA Docking System. The IDAs were scheduled to be delivered to ISS by the Dragon spacecraft on separate Commercial Resupply Services missions in 2015. IDA-1 was lost when CRS-7 was destroyed during launch in June 2015.

The NDS docking mechanism is androgynous, the first system to use low impact technology and the first system to allow both docking and berthing. It supports both autonomous and piloted dockings and features pyrotechnics for contingency undocking. Once mated the NDS interface can transfer power, data, commands, air, communication and in future implementations will be able to transfer water, fuel, oxidizer and pressurant as well. The passage for crew and cargo transfer has a diameter of 800 millimetres (31 in).

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