Senior Airmen Ryan Cassel, 407th Expeditionary Civil Engineer Squadron, flattens cement poured on the taxiway to repair cracks and pot holes, Sept. 22, 2008. Extreme heat conditions, along with normal wear and tear can cause cracks or pot holes on the runways, which makes it unsafe for aircraft. Airmen of the 407th ECES ensure the flight line is serviceable at all times by fixing any reported damage. Cassel is deployed from Pope Air Force Base, N.C.