SpaceX Starship’s Sonic Boom Creates Risk of Structural Damage, Test Finds

According to new data, SpaceX’s new Starship rocket produces a sonic boom so strong that it could cause property damage in the heavily populated residential area close to its launch site in South Texas, significantly above the estimated maximum noise levels.

The most thorough publicly available measurements to date for Elon Musk’s Starship, the biggest and most potent rocket ever built, are of the actual sound and air pressure produced by the rocket during its fifth test flight last month.

According to the new research, the 30-story-tall Starship makes ten times as much noise as SpaceX’s current Falcon 9 rocket, which company employs to launch astronauts and cargo into orbit. This week, SpaceX has another test planned.

According to Kent L. Gee, an independent acoustics engineer who carried out the monitoring, the noise during the October test flight was comparable to being 200 feet away from a Boeing 747 plane during takeoff for residents of South Padre Island and Port Isabel, which are roughly six miles from SpaceX’s launch site in South Texas.

In addition to being a researcher assisting NASA in its investigation of strategies to lessen the noise consequences caused by supersonic aircraft, Dr. Gee is the chairman of the physics and astronomy department at Brigham Young University in Provo, Utah. The Journal of the Acoustical Society of America released the test results on Friday.

Requests for comments from SpaceX and the Federal Aviation Administration were not answered.

According to NASA, the United States prohibited supersonic Concorde jets from flying over domestic territory while they were still in operation “so their resulting sonic booms won’t startle the public below or concern them about potential property damage.”

According to test results, the October Starship flying test was around 1.5 times as loud on the ground as the Concorde sonic boom.

The test’s biggest sound did not occur during the Starship’s liftoff, when the enormous rocket with 33 engines shot into the air. Instead, the test results showed that the sonic boom produced the highest noise approximately 6.5 minutes after liftoff, when the first-stage booster returned to the launchpad to self-land.

According to the statistics, the sound effect in the city of Port Isabel peaked at 105 dB during liftoff. That is about the same amount of noise produced by a typical rock concert or chainsaw operation. The highest perceived noise level in Port Isabel and South Padre Island as the first-stage booster returned was roughly 125 dB, or the sound of a gunshot at close range.

In contrast to the maximum of eight pounds per square foot that the F.A.A. had predicted for South Padre Island in October, the sound that struck the community momentarily produced an overpressure event that exceeded 11 pounds per square foot.

City authorities in Port Isabel engaged Terracon, a sound consultant from Houston, to perform separate testing last month. There, officials have grown more worried that the SpaceX launches could cause damage to residences in the about 5,000-person city.

According to municipal manager Jared Hockema, Terracon discovered a peak sound pressure level of 144.6 dB as the rocket dropped, which is also higher than Port Isabel had anticipated.

According to Mr. Hockema, “we are all for economic development and the work SpaceX is doing.” “All we want is economic development that complies with the law and doesn’t harm the environment or current residents.”

The F.A.A. states that when the pressurization level reaches 10 pounds per square foot, it might cause mild property damage, such as plaster cracks or fractures in “older and weakened, or poorly mounted windows,” especially if this level happens frequently during launches. According to the organization, this is unlikely to happen until the amount reaches roughly 20 pounds per square foot.

Car alarms went off on the streets where the technicians were performing the sound monitoring during the October flying test. Additionally, Mr. Hockema stated that while no information has been gathered regarding the overall number of small damage claims, the city has received a number of reports from locals regarding the SpaceX launches.

Dr. Gee and his group installed testing equipment at eight different places, ranging from a private residence in Brownsville, the next big city, which is 22 miles away, to the rooftop of the Margaritaville Hotel in South Padre Island, a tourist enclave, which is six miles away.

Although there are dozens of homes in Boca Chica hamlet, which is less than two miles from the launchpad, and in neighboring rural regions, no testing were carried out closer to the launch site. The state park and national wildlife refuge that encircle the area are home to a number of rare or endangered birds and turtles, which could be negatively impacted by the noise.