McNary Airfield, located in Oregon’s capital city of Salem, is home to the Oregon Department of Aviation (ODA) and boasts two general aviation runways (5,811 and 5,145 feet) that support over 50,000 aircraft operations annually. McNary’s runways are unique in their design and pose a special kind of challenge for any pavement preservation technology. Both primary and secondary runways contain ¼-inch by ¼-inch breaking grooves that shorten stopping distances and allow McNary Airfield the ability to service larger jet aircraft.
The primary challenge when sealing this type of runway, and the main concern for ODA, is achieving a uniform coating on the pavement without filling in the breaking grooves. To make this happen, the application rate would either have to be extremely low (thus requiring several coats) or the material would need to display a gelatinous behavior that allows the material to ‘stand up’ on the pavement during heavier spread rate applications.
With high air traffic count throughout the day, McNary Airfield doesn’t have the luxury to shut down for extended periods while numerous “fly coats” are applied. ODA needed an expedited application of a tough material that would stand up on the pavement and give McNary runways the required protection while maintaining the surface breaking resistance, selecting CarbonSeal-FR. Weather conditions were sunny and clear with temperatures into the 70s. Due to the unusually high concern about maintaining the integrity of the breaking grooves ODA officials were on hand to closely watch the completion of the first runway installation. Airport officials were pleased and expectations were met as the CarbonSeal-FR uniformly coated the runway grooves without flooding the individual channels.
Once again McNary’s runway intersection proved to be one of the more intense moments of an airport installation as RLC crews were afforded a short window and only one shot to get it right before air traffic landing gears would re-deploy onto the capital. The ‘V’ shaped relation between the two runways created an abnormally larger intersection so there was more ground to cover in the allotted time, but RLC completed the application in time.
Additional information and technical data on CarbonSeal-FR can be found at www.coepolymer.com.