Tucsonans flooded social media sites Wednesday night speculating on what caused a loud boom heard - and felt - over a chunk of the city.

Tweet messages started about 7:45 p.m., many from west-side and midtown residents, saying a large explosion rattled windows and shook the ground.

Tucson police received reports of two jets flying over about 7:40 p.m., just before the boom was heard, said spokesman Sgt. Chris Widmer. But it still isn't known whether it was a sonic boom.

The Pima County Sheriff's Department contacted and ruled out Davis-Monthan Air Force Base, Pinal Army National Guard, Tucson International Airport, the area's copper mines, Southwest Gas, El Paso Gas and Tucson Electric Power as sources, said sheriff's spokesman Deputy Tom Peine.

No one could be reached for comment at Luke Air Force Base near Phoenix, nor at Nellis Air Force Base near Las Vegas on Wednesday night. However, Nellis is conducting Red Flag training missions, including night flying, the base said in a recent news release. That training, attended by Air Force personnel from across the nation, began Monday and runs through March 15. More than 125 aircraft were scheduled to depart Nellis twice a day around noon and again around 6 p.m. Aircraft may remain in the air for up to five hours, the base said in the news release.

Nonetheless, Airman Christine Griffiths, of the 355th Fighter Wing at D-M, said all Red Flag exercises are conducted in Nevada, and no planes "are flying fast enough to make a sonic boom."

In Tucson, the city's 911 communications center received about 100 calls in a 45-minute period, said Capt. Adam Goldberg, a Northwest Fire District spokesman.

The U.S. Geological Survey Earthquake Center did not register any movement on its systems Wednesday regarding the noise over Tucson, said Jerald Meadows, a National Weather Service spokesman in Tucson. "They did not even register a bleep," Meadows said.

"We heard and felt out near Tucson Estates" on the far west side, Kathy Nelson Ricker posted on the Arizona Daily Star's Facebook page.

One resident at East River Road and North Campbell Avenue said she even looked outside to see if a car had slammed a house.

And workers at a call center at West River Road and North La Cholla Boulevard said the boom seemed to shake their building.


A Thunderbird pilot from Davis-Monthan Air Force Base, who was practicing for a weekend air show over Tucson last April 13, created a sonic boom that shattered windows when he surpassed the speed of sound for several seconds.

Damage to Tucson homes and businesses came to more than $22,000. The Air Force settled about 47 claims ranging from $30 to several thousand dollars apiece.

An investigation attributed the boom to pilot error.

Sources: Arizona Daily Star and Air Force Times archives

Contact reporter Carmen Duarte at cduarte@azstarnet.com or 573-4104.