Canadair CL-227 Sentinel
The CL-227 Sentinel is a remote-controlled unmanned aerial vehicle (UAV) made by Canadair.
It displays a distinctively unusual bulbous hourglass profile. Lift is provided by a set of coaxial rotors emanating from the waist of the system. The engine air is exhausted upwards to minimize the infrared signature. The blades are made of composite materials as well as all the external skin and legs, in an attempt to reduce the radar signature. The main structure is made mostly of aluminium.
The prototype of the CL-227 was designed in 1977, and was made available to NATO allied clients in the early 1980s. In the late 1990s it was replaced by an updated version, the CL-327.
Bombardier Aerospace CL-327 Guardian
The CL-327 was developed as an ungraded and advance version of the CL-227. The new UAV production line began in 1996 under Bombardier Aerospace, which acquired the assets of Canadair, the original developer of the CL-227.