Dream Chaser Scale Model
Technicians in the Aerospace Composite Model Develop Section are preparing a Dream Chaser® model for a buffet test in the Transonic Dynamics Tunnel at NASA Langley. The scale model of the Sierra Nevada Corporation's (www.sncspace.com) Dream Chaser® lifting body spacecraft, based on the Langley HL-20, will be mated to a scale version of United Launch Alliance Atlas V rocket for the test.
With the help of hundreds of transducers, engineers will look at the pressure fluctuations the model and stack experience during launch and ascent to orbit, especially at transonic speeds.
Predicting buffet forces on launch vehicles as they approach the speed of sound can be challenging due to the way shock waves form on the surface of the vehicle. These shock waves and the resulting large pressure changes can cause unstable conditions and large buffet forces that affect the vehicle as it accelerates through the speed of sound. This kind of data is important because the Dream Chaser® is a blunt-nosed winged body, a potentially complex spacecraft shape to fly on the tip of a rocket.
Credit: NASA/Sean Smith