The CL-327 "Guardian", an improved version of the CL-327 "Sentinel", benefits from a developmental history that dates as far back as 1964. The Sentinel participated in the Navy MAVUS programs in the mid 1990s, with several demonstration flights culminating in a final demo at sea, landing on the USS Vandegrift and making several automatic approaches. A modified Sentinel, known as the "Puma", was proposed to the US military for its TUAV program in 1996.
The Guardian entered low rate production in 1996, with one system currently on short-term lease to the Royal Australian Army.The Guardian was one of three UAV systems selected to participate in the Navy VTOL UAV demonstration program in 1998. More than 50 hours of successful flights were completed, despite an accident in June 1998 when a fuel tank separated from the aircraft, causing fuel starvation and subsequent loss of the aircraft. Further technical problems have since plagued the vehicle, delaying planned shipborne tests until late 1999. Concern over the Guardian’s ability to meet the speed, payload, and endurance criteria prompted Bombardier to withdraw from the Navy VTUAV competition in September 1999.
