Performance, Stability & Control Wind Tunnel Tests
SPACE ACCESS VEHICLES
AERODYNAMIC FORCES ON SPACE ACCESS VEHICLES
The Performance, Stability & Control test technique is utilized to understand the unique aerodynamic forces that a Space Access Vehicle is subjected to during flight. During these wind tunnel tests, Calspan configures the capsule and/or the lifting body for evaluation by an aerodynamicist to evaluate the efficiency of the following control surfaces:
- Aerodynamic fairings which are typically used on capsules for control.
- Lifting surfaces (short wings) that are on the lifting bodies to allow landing on a conventional runway.
Control of these vehicles utilizing aerodynamic forces is limited to the re-entry phase of flight or during an abort event during liftoff.
In order to support the space access vehicle development, the following are typical test objectives:
- Validate overall re-entry and abort performance of the vehicle.
- Determine the contribution of components (nozzles, fairings, and blended wing/body) to the total aircraft aerodynamic characteristics.
- Determine basic/combined control effectiveness and sizing for fairings/stabilizers at high AOA.
- Pressure distributions for loads analysis and CFD validation.
- Measure loads on the control surfaces.
During the wind tunnel test, a customer may wish to study a number of aerodynamic configurations and components to determine their effect on the overall performance through a range of model incidences, roll angles and Mach numbers. Overall loads on the model is measured by a precision internal strain gauge balance and converted to aerodynamic coefficients (e.g., Lift, drag, pitching moment, etc.). Calspan applies industry standard data corrections to offset tunnel effects (i.e., remove effects of the test not representative to a full-scale aircraft).