Sonic Booms are rare and hard to miss. But when the president is in town the event can become a national incident as it did on Tuesday.

Kirkland recreational-pilot Lee Dailey and his passenger Laura Joseph were returning from a trip to Lake Chelan Tuesday, when they landed on Lake Washington in Kenmore in his private Cessna floatplane, reports said.

But the average approach and landing caused a not so average response as the plane violated President Barack Obama’s airspace. The president was in town for Democratic fundraisers and to talk with local business owners.

Two F-15 jets were launched from the 142nd Air National Guard unit based in Portland, Ore., rattling buildings and fraying nerves as they exceeded the sound barrier. The shock waves were reportedly heard and felt from Portland to North Seattle.

Dailey and Joseph were met at the dock by federal agents who informed them that they had violated the president’s air space. The two were interviewed by the Secret Service agents, who also inspected the plane.

Dailey and Joseph will have to wait for a few weeks for the investigation to conclude and find out if and what penalties they may face.

The speed for breaking the sound barrier is called Mach 1, attained once an aircraft reaches 761 mph at sea level. Sonic booms result from pressurized sound energy. They can range from building-shaking booms caused by a fighter jet, or a crack from a whip. Click here to learn more about sonic booms.

Immediately after the booms, customers and workers exited businesses at South 324th Street and Pacific Highway South in downtown Federal Way to inquire about the cause of the two window-shaking booms, which took place just seconds apart. People circled the building shared by The Mirror, Comcast and Main Japanese Buffet, searching for the source of the booms.