The helicopters, by Lockheed Martin and Kaman Aerospace, were to return to the United States next month but have proved so successful they will remain in Afghanistan until September.
"K-MAX has proven its value to us in-theater, enabling us to safely deliver cargo to forward areas," said Marine Corps Maj. Kyle O'Connor, who is overseeing the deployment. "We are moving cargo without putting any Marines, soldiers or airmen at risk.
"If we had a fleet of these things flying 24-7, we could move cargo around and not put people in jeopardy."
In less than four months, the two unmanned aircraft delivered more than 1 million pounds of cargo, from 4,299-pound sling loads to 28,800-pound sling loads in a day to combat zones.
"The record lift and readiness numbers we're seeing in-theater are a testament to the aircraft's rugged design and its capability to reliably perform repetitive lift autonomously," said Roger Il Grande, director of airborne systems for Lockheed Martin's Mission System & Systems business. "The more deliveries the unmanned K-MAX makes, the more we remove the opposition's ability to undermine our objectives with IED's, and threaten the lives of our ground forces."