The United Launch Alliance (ULA) joint venture between Lockheed Martin and Boeing Company has unveiled a new aerodynamic configuration for its Atlas V rocket, which will take Boeing’s CST-100 Starliner capsule to the international Space Station (ISS) on behalf of Nasa.

The older version of CST-100 Starliner was facing issues with its aerodynamic stability and loads.

Featuring an aeroskirt aft of the spacecraft, the configuration helps to extend the Starliner service module cylindrical surface.

The configuration has also improved the aerodynamic characteristics of the integrated launch configuration and brings loads margins back to acceptable flight levels.

"The collective team of Nasa, Boeing and ULA completed three wind tunnel tests in six months to investigate the aerodynamic stability of various configurations and to anchor our analytical predictions."

ULA human and commercial services vice-president Gary Wentz said: “Through incredible coordination and continued innovative thinking, the collective team of Nasa, Boeing and ULA completed three wind tunnel tests in six months to investigate the aerodynamic stability of various configurations and to anchor our analytical predictions.

“Based on that information, we updated the configuration for the Atlas V Starliner integrated vehicle stack.

“This configuration is unique because it combines the Atlas V launch vehicle without a payload fairing with Boeing’s Starliner capsule, resulting in different aerodynamic interactions.” 

The company will start manufacturing the aeroskirt at its factory in Decatur, Alabama, US, in this month.

Designed to be jettisoned for better performance, the aeroskirt will smooth the airflow around the vehicle during ascent and ensure crew safety.

Earlier this month, ULA concluded the preliminary design review of the structure.

Nasa is planning to test an unmanned mission with Starliner aboard Atlas V by 2018, which will be followed by other operational missions.


Image: A United Launch Alliance (ULA) Atlas V rocket with the CST-100 Starliner capsule. Photo: courtesy of ULA/Boeing.