The FAA has granted a 333 exemption to the Yamaha R-MAX, a remote-controlled crop dusting unmanned helicopter that tips the scales at over 200lbs fully-loaded. The R-MAX was developed in Japan in the 90’s and is a great tool for “precision agriculture”, which allows farmers to precisely target areas in a more efficient and cost-effective manner. From the FAA pdf:
The Yamaha RMAX is a remotely-piloted rotorcraft. It is 9 feet long and 3 feet 6 inches tall, has an empty weight of 141 lbs. and a load capacity of about 61 pounds for both liquid and
granular applications. The main rotor is about 10 feet in diameter and extends 4 feet from either side of the RMAX and less than 3 feet from its front. The RMAX usually flies at a speed of no more than 12 mph (with a maximum speed of 45 mph). It is powered by a 2- cylinder, 246 cc engine that uses regular unleaded fuel with 2-stroke engine oil with a maximum output of 21 horsepower.
This version of the R-MAX isn’t capable of flying autonomously, so only line-of-site commercial use is permitted, but there is a varient called the R-BAT which was developed jointly by Northrop Grumman and Yamaha, and is inteded for military and civil use.