An unused $500,000 grant from the federal government to Laughlin/Bullhead International Airport is expected to expire on Tuesday. The grant was awarded to the airport by the U.S. Department of Transportation to help it secure scheduled airline service. The Mohave Valley Daily News reports that airport officials intend to apply for a new grant in April 2014. Airport director David Gaines declined to reveal which airline the Mohave County Airport Authority is negotiating with, but noted that the discussions are continuing. The grant had been extended a couple of times in the past.