WASHINGTON - NASA and SpaceX are targeting a 3:25 p.m. EDT launch on Friday, April 18, of SpaceX's third cargo resupply mission to the International Space Station from Cape Canaveral Air Force Station in Florida. NASA Television coverage will begin at 2:15 p.m. The company's April 14 launch to the orbiting laboratory was scrubbed due to a helium leak in the Falcon 9 rocket that will launch the Dragon spacecraft to the space station.

Dragon is carrying to the space station almost 5,000 pounds of science and research, crew supplies, vehicle hardware and spacewalk tools -- all to support the crew and more than 150 scientific investigations planned for Expeditions 39 and 40. If needed, another launch attempt will take place at 3:02 p.m. Saturday, April 19.

An April 18 launch will allow the space station program to plan for a spacewalk on Wednesday, April 23, to replace a failed multiplexer-demultiplexer (MDM) relay system. The prime MDM, which is operating normally, and the failed backup computer provide commands to some space station systems, including the external cooling system, Solar Alpha Rotary joints and Mobile Transporter rail car.

With development completed under the Commercial Orbital Transportation Services (COTS) program, Dragon has begun operational flights. SpaceX has completed two operational flights and one test flight.

NASA contracts are the primary source of income for SpaceX's Dragon. The company, however, has additional plans for the vehicle. SpaceX has signed a marketing agreement with Bigelow Aerospace. The companies will jointly market flights to Bigelow's space habitats orbiting in low Earth orbit on board Dragon space vehicles. Bigelow says it can transport astronauts to its inflatable space stations using Dragon capsules and Falcon 9 launch vehicles for about $26 million per astronaut.

Dragon production is expected to remain steady until 2014, after which it will continue at a much slower pace. Because the Dragon is reusable, new spacecraft will not need to be manufactured for each mission. Instead, spacecraft that return from one mission will be sent on another.

However, over time, spacecraft will need to be replaced. In addition, SpaceX markets the Dragon for both government and commercial missions. With time, the company may need to expand its fleet of vehicles. Forecast International expects a new spacecraft to be produced periodically after SpaceX builds up an initial fleet of eight vehicles.

Source: NASA
Associated URL: http://www.nasa.gov/press/2014/april/spacex-launch-of-nasa-cargo-to-space-station-set-for-friday-spacewalk-wednesday/#.U0_Lk6JARF8
Author: B. Ostrove, Analyst