Frequently Asked Questions
Why are some days worse for noise than others?
Reagan National Airport has two operating patterns: North Flow and South Flow. On North Flow days, aircraft begin their descent over Southern Maryland before reaching the river, and then often use a "visual approach" to complete their landing procedures at Reagan National airport. On South Flow days, aircraft take off over the river in the direction of Southern Maryland, but veer west over Virginia before reaching us.
Aircraft noise seems to be worse than it was a couple of years ago. Why is this?
It is worse, for many neighbors. (For other neighbors, it has actually improved.)
There are multiple factors:
1) There are now many more North Flow days than there are South Flow days. According to MWAA and FAA officials, the airport used to operate approximately 50% of the time in North Flow, and 50% of the time in South Flow, but "in the past couple of years" the ratio has been closer to 65% North and 35% South. According to unscientific logs we have taken, the numbers may be even worse than that - 75% or more! MWAA attributed this to changing weather patterns.
2) The NextGen aircraft guidance system was rolled out to Reagan National Airport around 2014. This system guides aircraft by GPS rather than by radar, as older systems did. The effect of this is to make "highways in the sky" - more precise paths which aircraft follow, rather than the more dispersed paths that were followed before. If you happen to live under one of these "highways", the effect is that you will have aircraft going over your house every few minutes on bad days.
3) DCA is busier than ever, with more flights serving more passengers. Airlines are meeting market demands to the extent that they can, given the relatively small size of the airport. Congress is a big fan of having a convenient airport that takes them to and from their districts, and over time has relaxed restrictions around the perimiter rule, meaning that flights can serve a wider area of the US. If DCA air traffic bothers you, consider voting with your dollar and using IAD instead.
How can I complain?
We wrote an article which goes into detail on how to file a good complaint. Click on the link and follow the guidance there.
How can I see how low aircraft are?
Use the Webtrak system, which shows a visualization of arriving and departing flights on an hour delay.
Why did the FAA Implement NextGen?
The stated goals of NextGen are to improve efficiency of airports (more flights per hour) and to save fuel (by reducing flight times, and making descents more efficient.) FAA state anticipated savings of $160 billion by 2030.
How low are planes allowed to be?
Pilots flying planes descending on a visual approach to the airport may control their own altitude. Depending on weather (e.g. cloud cover) this may mean that they fly lower on some days rather than others.
The recommended angle of descent, according to an FAA official we spoke to, is between 2.2 and 3 degrees. To figure out what that means for you, you can right click on google maps to "measure distance" from your house to the airport, and then plug those numbers into a Right Angle Triangle Calculator (fill in "side b" and "Angle A or B").
For example, Accokeek is between 53,000 and 68,000 feet from Reagan National. At 60,000 feet out, on a descent angle of 2.2 degrees aircraft should not be much lower than 2,300 feet. At a descent angle of 3 degree, aircraft should be at around 3,140 feet.
What do you hope to accomplish?
We realize that planes need to fly somewhere, and that we'll never be completely free of aircraft noise. However, we do believe that the situation has become inequitable in recent years, and that there are realistic incremental improvements that were within reach.
a) Restore the North Flow / South Flow ratio to close to 50/50. We don't believe there are any good reasons for Southern Maryland to bear the brunt of the loudest aircraft traffic. FAA defaults to North Flow on calm weather days.
b) Use the river to approach. There's a mile wide river immediately to our west. There's no good reason that aircraft shouldn't use it.
c) Failing that, consider a "Fan In" approach. Computer guided approaches shouldn't reduce flexibility; if anything, flexibility can be improved. Instead of bringing all planes in through a narrow corridor, stagger the approaches by 100 yards over a few miles wide. A couple of planes an hour is very different from a plane every 2 or 3 minutes.
d) Fix the noise monitor locations. The location of the noise monitor on W Tantallon Drive is under-representing noise pollution in Fort Washington; far more air traffic passes over Hatton Point, 3500 feet to the west; a monitor should be added there. Add noise monitors in Accokeek, which currently has none.
How can I help?
We seek volunteers to help with research, writing, getting the word out, and political action. If you're interested in helping, please join our volunteers email list. If you'd like to be notified when we have face to face meetings, and when new research is published, join our announcements email list.
