Plane noise takes off in fall

• Portland International Airport served a record 15 million passengers in 2013, an increase of 4.4 percent from the year prior.

• The number of flights, however, decreased by 2.9 percent from 2012 to 2013. Last year, Portland International Airport recorded 209,909 operations (takeoffs or arrivals), compared with 216,195 the year before.

• When wind blows from the east, 45 percent of flights to and from PDX fly over Clark County. When wind blows from the west, that percentage dips to 25 percent.

• This summer, the airport served 4.7 million passengers — a 7.4 percent increase over last summer’s 4.38 million passengers.

• Military flight operations are on the rise. This summer saw 1,313 flights, an increase of 15.35 percent from summer 2013.

Learn more

• Have questions or comments about aircraft noise? Call the Noise Management Department at 1-800-938-6647 or visit www.portofportland.com/noise_mgmt_home.aspx

Get involved

• Next PDX Citizen Noise Advisory Committee meeting

• Where: Portland International Airport, St. Helens B Conference Room, 7000 N.E. Airport Way

• When: 5:30 to 8:30 p.m. Thursday, Nov. 13.

Fall — it’s the season when leaves change color, the weather gets cooler and more airplanes fly overhead. Wait, what? When wind direction shifts in autumn, air traffic from Portland International Airport also shifts, causing some people in Clark County, who didn’t hear a peep of aircraft noise in the summer, to get an earful.

Planes take off and land against the wind. In the cooler months, the Portland-metro area tends to get more east winds. During this time, about 45 percent of flights to and from the airport go over Clark County, and the rest fly over Oregon. During the summer, when west winds are common, about 25 percent of flights fly over Clark County.

“There’s not a lot that can be done about that because of where the runways are located and the approach,” said Craig Walker, one of three Clark County representatives on the PDX Citizen Noise Advisory Committee and a recreational pilot.

Walker lives in Camas near Lacamas Lake, where he gets noise from shuttle flights to and from Seattle. Those same flights rumble over the rural hills of Hockinson.

People living west of where Interstate 205 and Interstate 5 merge, in Salmon Creek or Felida, will hear more noise from flights arriving from the east coast, Walker said. The planes descend over Vancouver Lake and turn around to line up with the runway, facing against the wind.

“Yes, we do hear the noise of the airplanes. But, there has been no written or oral complaint to the North Salmon Creek Neighborhood Association in the past two years at least,” said the association’s co-president, Ann Foster.

She said the Port of Portland attended a neighborhood association meeting and explained the flight paths that go over Salmon Creek.

Although noise always plagues downtown Vancouver, it’s this seasonal shift that gets some people riled up.

Phil Stenstrom, noise program manager at the Port of Portland, chatted with local residents at the Vancouver Farmers Market this summer about noise management. People’s level of tolerance runs the gamut, he said; some people love the sights and sounds of aircraft, while others call the noise hotline a few times a day to complain.

As the economy improves, more people are flying through PDX, which saw record-breaking passenger traffic last year. So far, the increase in passengers hasn’t led to an increase in the number of flights. Airlines are filling more seats, Stenstrom said, and newer commercial planes are bigger.

How aircraft noise works

Around 5,000 feet and lower is where people can hear passenger airplanes, Walker said.

Military jet takeoffs can be the noisiest; although they quickly climb to 10,000 feet, people can still hear them at that altitude. This summer saw an uptick in military flight operations, which were heaviest in August. The military airbase, home of the 142nd Fighter Wing of the Oregon Air National Guard, is on the south runway.

Walker said that the Columbia River is a natural flight corridor that minimizes residents’ noise exposure. If the river were wider, he said there would be fewer complaints.

During a west wind, departing flights head over the river and climb several thousand feet before turning toward their destination, which eases the amount of noise in west Clark County. Arrivals are noisier because they’re gradually descending.

“You’re better off than if you were in Portland,” Walker said.

Northeast Airport Way gets plenty of noise, but it’s an industrial area that doesn’t impact many homeowners. In a west wind, arriving planes fly in over Gresham, Ore., at around 4,000 feet.

New technology, less noise?

Next Generation Air Transportation System, or NextGen, could change the noise situation. Using the old method of ground navigation, planes descend in a stair-step manner; they drop a thousand feet, fly for a while, then drop another thousand feet. With NextGen satellite navigation, planes use GPS to descend more smoothly and precisely — more of a sweeping motion, than a staircase.

“They’re coming in with less power on a curved approach,” Walker said, adding that the pre-programmed routes takes less fuel, less time and are less noisy.

Things aren’t so bad on this side of the river, or really, in this area of the country, Walker said.

He points toward San Diego International Airport, which has one of the steepest descents right over downtown. While landing, passengers are sometimes able to look into downtown buildings and be close enough to see the people inside them.