Ryan ChartrandYesterday afternoon Cal Poly students and county residents felt shaking from sonic booms caused by military aircraft, local officials said.
Sheriff’s Sergeant and Public Information Officer Brian Hascall said that the shaking began a little after 1 p.m. and that the Sheriff’s Department was inundated with calls from people wondering if the shaking was an earthquake.
Edwards Air Force Base personnel are doing sonic testing and training exercises in the area, Hascall said.
NASA Dryden Flight Research Center is conducting the sonic boom tests July 18 to July 20 from 8 a.m. to 3 p.m. to research how modern housing construction responds structurally to sonic booms.
The LA Daily News said that similar testing was done last year using an older home, and that data from the two separate tests will be compared.
“That was a rickety house that was to be demolished,” said Ed Haering, a Dryden sonic-boom researcher. “This is a modern house. We expect it will be a lot quieter.”
The research is called the Housing Structural Response to Sonic Booms Test, and will study how both normal and low-amplitude booms affect the house.
A total of four low-boom and two normal-intensity boom missions are scheduled, with up to six sonic booms on each mission. Although booms may occur six minutes apart, no more than two missions will be flown on one day.
Haering said that the difference between a normal and low-amplitude boom is the pounds per square foot of air pressure. Normal booms have one to two pounds per square foot, while low-amplitude booms have one-tenth of a pound per square foot of pressure.
NASA officials said that sonic booms are the result of supersonic aircraft pushing aside air molecules with great force, resulting in a shock wave.
This wave transmits a cone of pressurized air molecules that extend to the ground and move outward in all directions. When the cone spreads across the landscape along the flight path, a continuous sonic boom occurs along the entire width of the cone’s base.
NASA Dryden will record data with more than 100 sensors that are located inside and outside the house, as well as with mounted microphones on a 35-foot tower in a nearby field.
An Air Force Test Pilot School L-23 Blanik sailplane containing NASA Dryden microphone equipment will collect airborne sonic boom data.