That rumbling you heard Thursday morning was caused by two fighter jets from Edwards Air Force Base on a practice flight over what is part of a huge offshore area used for various military activities.
The two jets an F-22 and an F-16 both broke the sound barrier as part of a test flight on a component of the F-22, said John Haire, an Edwards Air Force Base spokesman.
The flight test was being monitored by about 40 technicians in a control room there, he said.
Test flights and maneuvers along the coast occur almost every week, Haire said.
The 36,000-square-mile test range, called the Sea Test Range, is the Department of Defenses largest over-water range. Miles off the coast, it stretches from San Nicolas Island in the south to the San Simeon area in the north.
The Navy restricts access to the sea and airspace when using the range, said Kimberly Gearhart, a public affairs officer at the Naval Base Ventura County.
Vandenberg Air Force Base, which is always kept abreast of military exercises off the coast, believed the rattling Thursday was from an earthquake.
This isnt the first time sonic booms have prompted Central Coast residents to think theyd felt an earthquake, Haire said. Whenever it is cold and damp, supersonic sound waves travel farther than under other weather conditions, and thats what generated the rattling Thursday, he said.
According to the Navy, which oversees the range, activities there include carrier strike-group exercises; high-energy laser weapons testing; ICBM, missile defense and satellite launch support; and submarine, surface and air-launched cruise weapons. For more information, go to www.navair.navy.mil/ranges/SEA/index.htm.