Photo Courtesy of NASA
Space-station-bound rocket exploded after launch, but pad is intact.

The explosion of an unmanned rocket carrying cargo to the International Space Station (ISS) on Oct. 28 has once again put the National Aeronautics and Space Administration's privatization program in the spotlight.

Within seconds of liftoff, the first stage of Oribital Sciences Corp.'s Antares rocket self-destructed, scattering debris across the southern end of Wallops Island, Va. The Virginia Commercial Spaceflight Authority leases a flight facility from the National Aeronautical and Space Administration. Most of the debris fell within an 8,500-ft safety perimeter. According to NASA, no hazardous substances or obvious signs of water pollution resulting from the explosion have been detected.

Although an exact cause of the blast has not been determined, speculation has centered on the liquid-fueled rocket's two Aerojet Rocketdyne AJ-26, engines manufactured in the Soviet Union more than 40 years ago and subsequently refurbished with modern components. The engines, which have been used on the four previous successful Antares launches, had undergone hot-fire acceptance testing at a separate NASA facility before being integrated into the vehicle, according to Orbital Sciences documents.

In addition to the rocket booster, the explosion also destroyed Orbital Sciences' Cygnus spacecraft, which carried a 5,050-lb payload that included 26 mini-satellites that were to provide geospatial imagery to Dayton, Ohio-based Woolpert for a variety of land-use, environmental and energy projects.

Though NASA's six-year-old program of outsourcing launches to the private sector is expected to continue, the Antares explosion may lead to greater scrutiny of the agency's contracting. Congress wants to step down reliance on Russia to transport astronauts to and from the ISS. Funds for a new, more powerful Atlas rocket engine are included in the proposed FY2015 federal budget for the U.S. Air Force, which has overseen 50 successful launches of the current Atlas V by a Lockheed Martin-Boeing joint venture.

An initial assessment of the ocean-side launch complex found that the pad and its major infrastructure escaped severe damage, although a more thorough inspection will determine the full extent of the explosion's effects. Orbital Sciences officials say they are insured for the loss of the rocket and spacecraft, valued at $200 million, and any needed facility repairs.

Still, Orbital Sciences Executive Vice President Frank Culbertson told a conference call of investors and analysts on Oct. 29 that, due to "serious technical and supply challenges" with the AJ-26, the company began researching propulsion-system alternatives last year. A new system, developed by Alliant Techsystems, was to be used for launches in 2016. Culbertson said the process could be accelerated if the AJ26 is implicated in the failure. Orbital Sciences and ATK announced merger plans earlier this year.

The failed launch was to be Orbital Science's third of eight ISS resupply missions under it $1.9-billion Commercial Resupply Services (CRS) contract with NASA, initiated following the 2011 end of the space-shuttle program. NASA's other CRS contractor, Hawthorne, Cal.-based SpaceX, has used NASA facilities at Cape Canaveral, Fla., to successfully launch three missions to the ISS using its Falcon 9 v1.1 rocket, with the next one set for Dec. 9.

SpaceX also is experimenting with a modified, reusable version of its Falcon 9 rocket for two-way transport applications, although an August test launch at the company's McGregor, Texas, development facility ended in failure.

Culbertson told the investors that the Antares explosion has not derailed Orbital Sciences' plans to bid for a share of NASA's second CRS program; those flights would use the new propulsion system.

"When we look at all these events that occur flawlessly and go well, we need to recognize how difficult and demanding this business really is," said Bill Gerstenmeyer, associate administrator of NASA's Human Exploration and Operations directorate, at a press conference.