Military jets flying over Keene reportedly shook buildings and made a loud sound, but officials insisted they didn't cause a sonic boom.The Massachusetts Air National Guard said military jets doing practice exercises over Keene were responsible for the noise reported about 2:20 p.m. Wednesday. Officials said the jets were conducting low-level air defense training.Residents of Keene, Swanzey and nearby areas reported hearing the noise, describing it as sounding like an explosion and feeling like an earthquake.But the Massachusetts Air National Guard said the jets stayed at subsonic speeds the entire time. It said air traffic control officials and the pilots' on-board systems confirmed that the jets stayed at subsonic speeds.National Guard officials said the sound was caused by normal jet engine noise. They said the jets were flying at altitudes between 10,000 and 12,000 feet.12967056

Military jets flying over Keene reportedly shook buildings and made a loud sound, but officials insisted they didn't cause a sonic boom.

The Massachusetts Air National Guard said military jets doing practice exercises over Keene were responsible for the noise reported about 2:20 p.m. Wednesday. Officials said the jets were conducting low-level air defense training.


Residents of Keene, Swanzey and nearby areas reported hearing the noise, describing it as sounding like an explosion and feeling like an earthquake.

But the Massachusetts Air National Guard said the jets stayed at subsonic speeds the entire time. It said air traffic control officials and the pilots' on-board systems confirmed that the jets stayed at subsonic speeds.

National Guard officials said the sound was caused by normal jet engine noise. They said the jets were flying at altitudes between 10,000 and 12,000 feet.