A year ago the U.S. Marine Corps began shopping for a UAV to deliver supplies, at least half a ton per trip, in order to get essential items (ammo, water, food) to combat troops in remote locations. The marines wanted the UAV in action within six months, but no one was able to come up with anything in time. Last month, the marines successfully tested a transport helicopter UAV. Some firms told the marines they were working on it, and one of these outfits, Kaman, modified its K-MAX manned helicopter to meet marine requirements. This month, another contender, Boeing, successfully met marine requirements as well, using its smaller A160T.
The first to meet the requirement was the Kaman K-MAX. This is a 5.4 ton helicopter with a cruising speed of 148 kilometers an hour and an endurance of over six hours. It can carry up to 2.7 tons slung underneath. This made the K-MAX an ideal candidate for the marine resupply UAV. When tested, it was able to carry a 680 kg (1,500 pound) sling load to 12,000 feet (3,900 meters), and hover. It was able to deliver 2.7 tons of cargo, to a point 270 kilometers distant, within six hours (two round trips). The K-MAX UAV can also carry up to four separate sling loads (totaling 1,568 kg, or 3,450 pounds).
The A160T carried 1.1 tons of cargo to a spot 135 kilometers distant, within six hours. The A160T did this by making two round trips carrying 568 kg (1,250 pound) sling loads. The A160T was also able to hover at 3,900 meters. The A160T does not have the carrying capacity of the K-MAX, but does hold the world record of unrefueled flight (18.7 hours.) The A160T was built mainly for reconnaissance, while the K-MAX is built for hauling stuff.
The A160T is a two ton helicopter, able to fly under remote control or under its own pre-programmed control. It has a top speed of 255 kilometers an hour, and was originally designed to operate for up to 40 hours carrying a payload of 136 kg (300 pounds).
The marines were confident enough in the K-MAX UAV to pay Kaman $860,000 last August to fund the conversion of the manned version of a Kaman helicopter to a UAV. Now the marines have to decide if they want to buy the K-MAX UAV, how many and how soon, or go for the smaller A160T.
Whichever helicopter UAV is used, it will use existing flight control software, which allows such aircraft to be moved from its base to its destination with minimal operator effort. Then, once the operator selects a landing area, the flight control software automatically lands the UAV. Once unloaded, the operator uses a few mouse clicks to order the UAV to take off, return to base and automatically land.