In a report issued last week, NASA’s Inspector General warned of delays in the schedule for the agency’s Commercial Crew Program that will more than likely push the launch of the first routine flight taking NASA astronauts to the International Space Station (ISS) back into late 2018, more than three years later that projected.

The program, in which NASA will partner with commercial ventures such as SpaceX and Boeing, plans to carry astronauts back and forth to the ISS, and reduce the agency’s reliance on the Russian Soyuz spacecraft for the missions.

SpaceX has a $2.6 billion contract to use a modified version of its Dragon cargo ship atop the company’s Falcon 9 rocket to provide NASA with the ferrying service, and Boeing is in the process of designing its CST-100 craft, designed to land with parachutes and airbags in the western US.  Boeing’s contract is worth $4.2 billion.

Both commercial ventures have the capability of carrying seven astronauts at a time, although NASA’s vision is now based on four-person missions, and using the available space to haul cargo to the ISS.

The Inspector General’s report stated, “While past funding shortfalls have contributed to the delay, technical challenges with the contractors’ spacecraft designs are now driving the schedule slippages.”

The report also was critical of the space agency, saying delays in responding to and processing contractor concerns added to the delays as well.

The crafts provided by both companies must meed the safety requirements developed by NASA for space travel, and the IG’s report found that the agency created “significant delays” during their evaluation of hazard reports provided by the companies that led to costly re-designs that could be required later in the development of the spacecraft.

The agency has depended on the Russian Soyuz since the Space Shuttle was taken out of service in 2011, and they were hoping for a commercial crew launch in 2015, but under-funding by Congress to the tune of about $1.1 billion, forced contractors to delay design work, production and testing.

NASA has plans to continue to operate the ISS through at least 2024, but the delays and problems with funding have some concerned about the station’s operation over the next few years.