Why is my house shaking?
A series of sonic booms more than 1.5 miles north-northeast of Hammonton left windows rattling, homes shaking and people up and down the coast asking that very question.
Gavin Hayes, a research geophysicist with the United States Geological Survey, confirmed several booms were reported between 1:30 p.m. and 3 p.m. Thursday afternoon.
An F-35C Joint Strike Fighter jet from Naval Air Station Patuxent River in Maryland may have created a “number of sonic booms” during flight tests off the New Jersey coast Thursday, said Connie Hempel, public affairs officer with the air station . The jet was accompanied by an F/A-18 aircraft during the test exercise.
Did you feel what made South Jersey shake?
“Aircraft from Naval Test Wing Atlantic were conducting routine flight testing in the Atlantic Test Ranges this afternoon that included activities which may have resulted in sonic booms,” Hempel said in a statement. “Test aircraft from the naval air station execute supersonic flights almost daily in the test track, and most of these sonic booms are never felt on land. However, under certain atmospheric conditions, there is an increased potential to hear the sound.”
“At least nine sonic booms were recorded in the following hour and a half. Reported from southern New Jersey along the Eastern Seaboard to Long Island, New York,” according to a USGS report on the incident.
Rob Coyne said he felt two booms within a five-minute period at about 1:30 p.m. at his Absecon home.
“In my house, my patio doors started shaking, the floor started shaking a little bit, and I saw my neighbor’s patio door shaking,” he said. “I knew it wasn’t me.”
A sonic boom is produced by an aircraft or other object flying at a speed equal to or exceeding the speed of sound and that is heard on the ground as a sound like a clap of thunder.
There are several factors that can influence sonic booms — weight, size and shape of the aircraft or vehicle, plus its altitude and flight path, and weather or atmospheric conditions, according to NASA’s website.
The distance it travels depends on the altitude of the jets, which results in a “boom carpet” — equivalent to 1 mile for each 1,000 feet of altitude, NASA’s website says.
Meteorologists can perhaps explain why the sound and tremor reports were reported over such a large area. It’s a phenomenon known as a temperature inversion. Normally, the warmest air in the atmosphere is near the ground, and it gets colder with height above the ground. During an inversion, the air nearest the ground is cold, while a layer of warmer air sits higher up in the sky. Sound travels more readily through warm air, so if an inversion were in place Thursday afternoon, sound waves would travel greater distances.
At first, Xiomara Martinez, 30, of Atlantic City, thought there was something wrong with her 2008 Nissan Altima when she was stopped at a traffic light on New Road and felt it rocking.
“At first, I thought it was my car needing to go into the shop,” Martinez said. “I never thought it could be a sonic boom. All I kept trying to figure out was when I was going to get my car in the shop. Thankfully, it’s not my car.”
Tim Kroll, deputy airport director at Atlantic City International Airport, said the airport was inundated with calls about the incident. The sonic boom did not affect air travel, Kroll said. Services around the region were not affected.
“It felt like a strong wind and my whole house just shook,” said Annette Santiago, of Pleasantville. “The second time it felt like the ground was shaking. I heard the windows moving, too. I thought I was going crazy, that it was just me hearing stuff. “
At about 2:30 p.m., the last effects of the sonic boom could be felt rattling the Atlantic City Boardwalk. The shake caused many to stop in their tracks.
Marcus Stein, 31, who had been visiting Atlantic City from South Florida, said he was just stepping onto the Boardwalk when it felt as if the area began to vibrate.
“I just want to know what happened. I mean, was it an earthquake?” he asked.
Otto Graham, who had been transporting passengers in her cart on the Atlantic City Boardwalk when the shaking occurred reported feeling four “bangs.”
“I said you know anything is possible in Atlantic City.”
Staff Writers Nicholas Huba, Andrew Albert and Dan Skeldon contributed to this report.