You can’t launch a rocket without breaking a few sound barriers, and NASA’s new Space Launch System (SLS) — which will be the most powerful rocket the agency has ever built — is no exception.
Motherboard reports the space agency conducted a sound test with a reduced scale SLS in June to get an idea of how loud the real deal will be when it launches astronauts deeper into space than ever sometime in the next decade. The answer? REALLY loud.
The sound generated by a rocket and its corresponding force and pressure go far beyond the sound barriers that are broken as the rocket accelerates to a velocity capable of escaping Earth’s gravitational pull. From the roar of the enormous engines to the exhaust generated by the rocket’s thrust, every sonic consideration must be taken into account to ensure the acoustic vibrations generated during liftoff don’t damage nearby facilities or the launch vehicle itself.
According to engineers at NASA’s Stennis Space Center rocket engine test site in Mississippi, the frequencies generated at launch are focused in the low and mid range — the same ranges capable of destroying standing structures like buildings.
The record for the loudest test ever conducted at Stennis still belongs to the Saturn V rocket’s first-stage, which featured five engines capable of generating 7.5 million pounds of thrust and powered NASA’s Apollo program to the moon. That test rang in at 204 decibles.
Saturn V could carry about 130 tons into Earth orbit, whereas the SLS will max out at an “unprecedented lift capability” of 143 tons, according to NASA, and have 10 to 20 percent more power than the Saturn V at a maximum of 9.2 million pounds of thrust. (RELATED: NASA Gives The ‘Go’ To Start Building Its Deep-Space Mars Rocket)
Typical contemporary rockets generate around 100,000 to 650,000 pounds of thrust for an average decibel rating of about 195 at launch.
“The noise the engines and boosters generate is so great that it can impact the rocket, and the crew, during liftoff,” NASA Marshall Space Flight Center acoustic engineer Jeremy Kenny said in the report. “We have to ensure we have the proper suppression system to basically turn that noise down to a safe level.”