Several projects present challenges to busy airfield Published Nov. 19, 2009 By Howdy Stout Tinker Public Affairs TINKER AIR FORCE BASE, Okla. -- X usually marks the spot. At Tinker, X means "don't use this runway." The large yellow X at either end of runway 12/30 indicates the runway is temporarily closed as construction crews work to improve and strengthen one of Tinker's two runways. The work is just one of several projects underway around the airfield, explains Marc Bradley, Airfield Operations manager for the 72nd Operational Support Squadron. Nearly $12 million in federal funding is being used to revamp the runways, taxiways and engine trim pads. In addition, there is a MILCON project to build a new three-bay hangar for the air logistics center. All while keeping the airfield open for business. "It's a logistics issue for us because we have to keep the airfield operational and still allow construction for airfield upgrades," Mr. Bradley said. The new funding is allowing the completion of work started in 2004 to strengthen and widen the keel -- or center section -- of Runway 12/30 with high-strength, load-bearing concrete while the runway's outer edges are reinforced with additional asphalt. Work done in 2004 and 2005 removed and replaced 520 feet of runway while the current work will replace a further 480 feet at the runway's northern end. "Runway 12/30 is an older runway, but a completely usable runway," Mr. Bradley explains, the work will increase the strength and durability of the runway, along with keeping the runway within standards. Ground-up concrete from the runway is mixed with lime and fly-ash to form a stable base to the runway. "It's almost like cement," explains Troy Merit, construction superintendent for the work on Runway 12/30. Next is a layer of asphalt that acts as a moisture-draining sub-base to the main concrete layer on top. "So any water trapped underneath the concrete is drained away," Mr. Merit says. "It's a good system. Once that's in place, it's pretty much waterproof until the job is done." The final layer is a two-foot-thick layer of concrete. Engineers monitor the concrete as it cures, with full strength achieved within several weeks of pouring. It will be fully cured within 28 days. Good weather and the ability to completely close the runway means construction is moving quickly, with work starting at the end of October and expected to be complete by February. But the closed runway means that routine maintenance work on Runway 17/35 involves coordination with flying units and the ability to work outside of flying hours to keep Tinker's only operational runway open. Twice a year crews use high-pressure water jets to remove the rubber marks left by aircraft tires on Runway 17/35. As Tinker's main runway, the accumulation of rubber quickly obscures the runway's paint markings. Once the rubber is removed, workers repaint the runway's centerline marking, touchdown zone markings and taxiway lead-in lines. "We get so much traffic on Runway 17/35 as our primary runway that we do rubber removal on Runway 17/35 twice a year," Mr. Bradley says. "It's amazing how fast the rubber deposits build back up." Most of the work is done at night when flying operations are slower. Routine maintenance and new construction work are also coordinated among the airfield's users, control tower, base engineers and the construction crews, Mr. Bradley explains. "Not only do you have to coordinate with the flying community, we have to coordinate with the contractors," he says. During construction, airfield operations personnel regularly monitor areas under construction to make sure construction crews are only where they need to be and that aircraft movements don't pose a danger to themselves or the crews. A case in point is the ongoing work to Taxiway Golf from Foxtrot to Echo in front of the Romeo ramp. Portions of the Taxiway Golf were upgraded earlier this year while another portion is scheduled to be improved early next year. During the construction, when aircraft were taxiing on taxiway echo near the construction site, coordination was crucial between the aircraft, construction crews, and ATC to ensure safety for everyone. "It's an operational and safety issue for us," Mr. Bradley says. "When this portion of the taxiway was under construction, the adjacent Romeo ramp area was not available for operating aircraft. Although operational aircraft can't use it, the ramp can be used for parking aircraft undergoing depot maintenance. But even then, aircraft will have to be towed as the jet blast could injure nearby construction crews. During all construction projects airfield management must determine how to allow aircraft and maintenance crews to operate safely until the project is completed. "Those are some of the considerations when we're working on an airfield construction project," Mr. Bradley says. Engineers are currently surveying the area near Bldg. 2280 for the construction of a new three-bay hangar for the ALC. Once construction begins, Airfield Operations will coordinate the revised aircraft parking plan at the ALC ramp. As with all new construction, the placement of a new hangar must meet strict guidelines. "Any new construction on this base has to meet new standards," Mr. Bradley said, "which is a bit of a challenge because most of this base was built before there were any criteria." However, Mr. Bradley adds, it is encouraging to see construction work at Tinker. Planning alone can take years before any signs of construction are visible. "It's such a long process that it's neat to see them actually pouring concrete," he said.