NASA does not have a complete plan to assure manned access to space through 2017, say Government Accountability Office (GAO) officials. The assessment came during a 28 March hearing before the House Committee on Science, Space and Technology covering the 'significant challenges' NASA faces in utilizing the International Space Station (ISS), where officials described risks associated with the commercial resupply effort even as preparations for the first commercial launch to ISS are well underway.

"If the international partner agreements and commercial service provider contracts do not materialize as NASA plans for the years beyond 2016, this could lead to a potential cargo shortfall," says GAO.

Of the 51 cargo resupply flights scheduled between 2012 and 2020, 40 are to use commercial launch providers. The first two commercial flights by SpaceX and Orbital Sciences are scheduled for 2012. The first, a SpaceX Falcon 9 rocket with a Dragon cargo capsule, is scheduled for launch on 30 April, with ISS docking shortly thereafter. Contracts with the two companies expire in 2016.

The organization also notes that funding levels for the related commercial crew development (CCDev) programme, conceived to develop human-rated commercial systems for transferring crew to the ISS, have consistently been lower than requested. A third round of CCDev, dubbed the commercial crew integrated capability (CCiCap), was conceived to partly offset those losses. Commercial crew launches are currently scheduled to begin in 2017. Test flights of human-rated commercial vehicles are not set to begin until 2014, and spacecraft programmes often suffer frequent delays and occasional failures.

The 2011 retirement of the Space Shuttle left NASA without an organic way to launch crew and cargo to the ISS. To fulfill its requirements, NASA has been purchasing cargo and crew flights from Russia.

Source: Flight International