The timing was perfect. Four years ago, Mills High School science teacher Art Fortgang was lecturing to his honor students about the physics of sound when, suddenly, the walls of his classroom began to shake. Directly overhead, a jet was making its final, screeching descent into San Francisco International Airport, just a mile and a half away. Normally, incoming planes don’t make much of a racket at Mills High: The school lies west of the airport in the suburb of Millbrae, and air traffic generally approaches from the east, over the San Francisco Bay. But on certain days of the year, particularly when the wind patterns change in May and October, incoming jets swoop directly over the school, rattling students, teachers, desks, and everything else in the flight path.
—David Kidd |
The periodic flyovers are a pain for Mills teachers and students. But that day, Fortgang vowed to design a project that would turn the distraction into a learning opportunity. When, in 1998, the airport announced that it was seeking public input on a planned runway expansion, the teacher’s idea took shape. “Nobody wants planes coming directly over them. The airport already knows that,” Fortgang says. “So instead of attacking the problem on an emotional level, I thought it might be useful to really study the sound levels of these airplanes in various pockets around the city. It’s possible that in some areas, the sound levels from these jets are higher than what the airport believes.”
Fortgang and Mills mathematics teacher Nils Headley raised $27,000 from the Toyota, GTE, and San Francisco Peninsula Community foundations to purchase sound meters, wind gauges, a radio scanner for listening to control tower communications, a Global Positioning System unit, three new personal computers, and a state-of-the-art weather station. Then Fortgang sent his students outside. First, they learned about sound absorption and reflection by honking their car horns at points around the city and calculating the impact of nearby trees and buildings on the sound readings. As the students became familiar with the equipment, Fortgang sent them out in three groups—one to a busy thoroughfare, one to the foothills, and another close to the bay—to take synchronized sound readings of airplanes passing overhead.
“It was interesting to see the difference between what we thought we were hearing and what the actual sound levels were,” says senior Suzan Muhamedcani, one of Fortgang’s students last year. “One of the most important things we learned is that experiments don’t always run perfectly. Sometimes we’d be out taking a sound reading, and cars would drive by or people would talk, and that would throw everything off.”
Although the students didn’t find any reason for the airport to change its flight patterns, they’ll continue to track noise pollution this fall. While Fortgang spends the school year in England through the Fulbright international teacher ex-change program, Tony Wilde, a British teacher, will monitor the project.
Whatever his students discover, Fortgang says, he expects they will get a better understanding of what it takes to conduct a good experiment. “Most projects at the high school and college level are cookbook experiments where the students can guess what the outcomes will be,” he says. “This is a prime example of a real-world experiment where all the participants, including the teacher, do not know what’s going to come out.”
