No, it’s not about making it look nice for anyone who happens to set eyes on it. It’s actually part of important research to learn more about the stresses put on different parts of a rocket as it hurtles toward supersonic speeds.
And the paint isn’t your run-of-the-mill semi-gloss enamel that you might pick up from your local Home Depot, either.
Instead, it’s a high-tech substance known as “pressure-sensitive paint” (PSP) that reacts with oxygen to produce light in response to buffeting against the rocket structure. Pink in color, the paint is applied to a small-scale model rocket that’s then tested in a wind tunnel, with high-speed cameras recording images under ultraviolet light.
Gathered data provides researchers with vital information that should ultimately lead to improvements in the aerodynamic design and capabilities of space rockets.
NASA says the video (top) shows a “visualization of the full-coverage measurements of unsteady pressure affecting a rocket, taken during the simulated launch of a wind tunnel test,” adding, “Spacecraft must be designed to withstand these dynamic forces, called buffeting, or risk being shaken to pieces.”
The pressure data is visualized as colors, with red showing higher-than-average pressure and blue representing lower-than-average pressure in the moments before the rocket hits the speed of sound.
The paint has been used for several years, but only in small research tunnels. However, a test carried out by the Air Force persuaded the NASA researchers that it’d be possible to adapt the system for their larger wind tunnel environment.
“There’s a lot we don’t understand about unsteady flow that this paint will help us figure out,” NASA’s Jim Ross said.
Buffeting is also measured using data gathered from tiny microphones attached to a model rocket, and the researchers plan to combine data from both methods to better understand how rockets experience airflow and how future designs can reduce those impacts.
