Space Station

Although the space station components supplied by the Russians have complied with most safety standards, two Russian-built modules still fall short in meeting some important requirements. These modules are the Zarya, which provides the initial propulsion and guidance functions for the space station, and the Service Module, which will provide living quarters, life support systems, and guidance functions after docking with Zarya. Significant areas of noncompliance on one or both of the modules include (1) inadequate shielding from orbital debris, (2) an inability to operate after losing cabin pressure, (3) a lack of verification for the design and service life of windows, and (4) excessive noise levels. NASA officials said that shortfalls in Russian funding, designs based on existing Russian hardware, and technical disagreements with Russian engineers are the main reasons the modules do not comply with safety requirements. NASA waived compliance with safety requirements after determining that the risks were acceptable, allowing Zarya to be launched. It has yet to approve all instances of noncompliance for the Service Module. The four most significant instances in which Zarya failed to meet safety requirements or had performance problems did not warrant compensation from the contractor, according to NASA.

GAO noted that: (1) Russian elements have complied with the majority of space station safety requirements, but Zarya and the Service Module still do not meet some important requirements; (2) according to NASA safety officials, significant areas of noncompliance include: (a) inadequate shielding from orbital debris on the Service Module; (b) inability of Zarya and the Service Module to operate after losing cabin pressure; (c) lack of verification for the design and service life of the Service Module windows; and (d) excessive noise levels in Zarya and the Service Module; (3) NASA officials said that shortfalls in Russian funding, designs based on existing Russian hardware, and technical disagreements with Russian engineers are the main reasons these modules do not comply with safety requirements; (4) NASA approved noncompliance with safety requirements after determining the risks were acceptable, allowing Zarya to be launched, but it has not yet approved all noncompliance cases for the Service Module; (5) NASA approved noncompliance with requirements for ability to operate after loss of pressure and noise levels on Zarya; (6) NASA approved noncompliance with requirements for debris shielding on the Service Module but has not yet approved noncompliance with requirements for ability to operate after loss of pressure, noise levels, and window design and service life; (7) NASA approves noncompliance with safety requirements when it determines that the risks are acceptable because plans are in place to mitigate risk or the deficiencies will last only a limited time; (8) NASA and the Russian space agency plan to correct safety deficiencies in orbit with future space station assembly and logistics flights; (9) however, the period of higher risk to the crews and the modules may increase if corrections are delayed for any reason; (10) correcting deficiencies in orbit may also be more difficult than on the ground and may take up time that the crews could spend on other activities such as research; (11) according to NASA, the four most significant cases in which Zarya did not meet safety requirements or had performance problems did not warrant compensation from the contractor; (12) two of the cases--inability to operate after loss of pressure and excessive noise--involved noncompliance with safety requirements; (13) the other two cases--defective batteries and poor air quality--involved performance problems in orbit; (14) the contractor agreed to reduce noise levels and replace the batteries at no charge to NASA; and (15) the two other problems did not result from failure to meet contractual requirements.