What a noise contour is
The Defense Department's AICUZ program (Air Installations Compatible Use Zones) has military airfields publish studies that map aircraft noise around the base. The noise zones are drawn as contours of average sound over a day, measured in DNL decibels, usually from 65 dB up. Many studies also map accident potential zones off the ends of the runways: areas where an accident is more likely if one happens, not a prediction that one will.
Defense guidance treats homes at 65 dB DNL and above as generally incompatible with the noise. It discourages new housing at 65 to 69 dB and strongly discourages it at 70 to 74 dB. Where homes are allowed, it recommends construction that cuts outdoor noise by at least 25 to 30 dB indoors.
Why it matters before you offer
- An average isn't a flyover. Jets training at night or on weekends can sound very different from a Saturday open house.
- County overlays can limit building. Around Andrews, Prince George's County's Military Installation Overlay Zone can limit structure heights, require sound-reducing construction for new homes and additions inside the noise contours, and bar some uses near the runways. St. Mary's County's AICUZ overlay around Pax River has sound-reduction rules too, and limits new homes in the loudest zones.
- The contract won't tell you. Most Maryland home sale contracts must say the property “may be located near a military installation.” That sentence goes in nearly every contract, so it says nothing about this house in particular.
The bases Curbnote checks
In Maryland:
- Joint Base Andrews (Prince George's County). Official study: the 2017 AICUZ study.
- NAS Patuxent River (St. Mary's and Calvert). The Navy released a new AICUZ study in August 2026. Curbnote's outline still follows the 2009 contours used in county zoning, so check the new study for any house near Pax River, including parts of Calvert County.
- Aberdeen Proving Ground (Harford), from the APG Joint Land Use Study.
- Naval Support Facility Indian Head (Charles), whose explosives testing can be heard for miles; see the state's installation page.
In Virginia: NAS Oceana and NALF Fentress, Naval Station Norfolk, Joint Base Langley-Eustis, Marine Corps Base Quantico and Fort Belvoir's Davison Army Airfield.
The outlines Curbnote uses are approximate, traced from the published studies. Near the edge of a contour, open the study itself, or ask the county planning office, before you rely on it.
Check it yourself
- Type the address above. If it falls inside a contour, the result names the base and links the study.
- Visit the house on a weekday and in the evening, not only at an open house, and ask neighbors how often they hear flights.
- Ask the county planning office whether the lot is in a military overlay zone, and what that limits.
- Moving on orders? Your installation's housing office knows the neighborhoods under the flight paths. The records checklist covers the rest.