In mid-2003 the U.S. Congress asked the General Accounting Office (GAO) to assess the effects of shuttle launch delays on the ISS. The GAO is an investigatory agency of the Congress. In September 2003 the GAO released a report titled Space Station: Impact of the Grounding of the Shuttle Fleet.

The GAO report noted that the delay caused a number of operational problems. Before the Columbia disaster a multi-purpose logistics module (MPLM) named Rafaello had been packed and readied for a March 2003 launch at Kennedy Space Center. This module had to be unpacked to provide preventative maintenance to some of the equipment inside. Repacking the MPLM for a future shuttle flight will take at least two months. The module will also have to be retested for flight prior to launch.

A giant solar array wing attached to a truss segment was to have launched in May 2003. The long launch delay pushed the wing past its storage time limit. NASA had to remove the wing and send it to a contractor to be retested and recertified. Batteries on truss sections waiting to be launched in 2003 had to be recharged. Prolonged storage had shortened their available life span. All of these problems resulted in unexpected costs in NASA's ISS program.

Grounding the shuttle also has negative effects on ISS research projects. NASA had planned to launch three major research facilities to the station during 2003. On-board experiments must be conducted using existing facilities. However some of this equipment needs to be replaced or repaired, particularly refrigeration and freezer units in the science section. These units have suffered some failures. NASA had planned to replace them during 2003 with the launch of a new and larger cold-temperature facility. One of the largest drawbacks to ISS science is the presence of only two crewmembers. The number of new and continuing experiments conducted during Expeditions 7 and 8 had to be reduced so the crews could devote more time to station maintenance and operation.

The GAO also found that shuttle delays affect the safety of the ISS. NASA had planned to transport a new on-orbit gyro to the station in March 2003 to replace a broken unit. The station includes four gyros that maintain the structure's orbital stability and permit navigational control. NASA scientists fear that problems could arise in the station's three remaining working gyros during a prolonged delay in shuttle flights. NASA had also planned to finish installing shielding on the Russian module Zvezda during 2003. Zvezda houses the ISS expedition crews. The module is supposed to be covered with twenty-three shielded panels to protect it from impacts by space debris. Only six panels have been installed so far. Every day that goes by without the additional shielding increases the risk that the module could be struck and damaged by debris.

Shuttle delays also affect America's ISS partners. The original cost-sharing plan was worked out in the 1998 Agreement among the Government of Canada, Governments of Member States of the European Space Agency, the Government of Japan, the Government of the Russian Federation, and the Government of the United Sates of

TABLE 5.6
International Space Station assembly as of February 2004

America Concerning Cooperation on the Civil International Space Station. This plan calls for NASA to pay the entire cost for ground operations and common supplies for the station. NASA is then reimbursed by the partner countries for their shares depending on their level of participation. Partner countries also fund operations and maintenance for any elements they contribute to the ISS, any research activities they conduct, and a share of common operating expenses. These costs will have to be adjusted as the shuttle fleet remains grounded and planned activities are cancelled.

In addition there is a political problem with relying on Russia to transport crews to the station and to launch extra Progress supply ships while the shuttle fleet is out of commission. The cash-strapped Russian Space Agency is expected to ask for money from NASA to make such flights. Under the Iran Nonproliferation Act of 2000 NASA is prohibited from making large payments to Russia unless it can be shown that Russia is not sharing sensitive technical information with Iran. The GAO notes that it is unclear how this issue would be resolved. The United States might have to ask its European partners to pay for such flights.

The GAO estimates that the United States spent $32 billion on the ISS between 1985 and 2002. At the time of GAO's report in 2003, NASA had received another $1.85 billion for fiscal year 2003 and was requesting $1.70 billion for fiscal year 2004.

In January 2004 U.S. President George Bush announced a new plan for America's space program. This plan calls for retirement of the space shuttle fleet by 2010. Bush also wants to end ISS assembly as soon as the core-complete configuration is obtained and eliminate all ISS research projects that do not support the new plans for space travel. In February 2004 NASA released its 2005 budget request which included $1.9 billion for the ISS program.

NASA had originally hoped to finish the core-complete station during 2004. NASA told the GAO that each month's delay in the shuttle program equals one month's delay in ISS assembly. As of July 2004 the shuttle's return to flight is not expected until fall or winter 2004, eighteen to twenty-two months after the Columbia disaster. Assuming that NASA's time estimate is correct, the delay would push ISS core completion well into 2005 and possibly 2006.