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Canadian Unmanned Aerial
Vehicles – a Brief Historical Background |
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The CL-89 Midge and CL-289 – Canadair's Early Lead in Reconnaissance Drone
Technology
In the early 1960s, Canadair began design of a 'Surveillance Drone System' –
essentially a recoverable missile capable of performing reconnaissance missions. Its CL-89 Midge[1] was
adopted for service by 4 NATO countries including Canada. The first operational use would not occur for
20 years when British Army Midges were deployed in the 1991 Gulf War. In the meantime, Canadair had
introduced the improved CL-289 which serves Germany, France, and Italy. [2] The CL-289 was also intended
for the CF but this plan was scuttled by David Collinette's 1990 defence budget. The CL-289 has proven to
be highly successful in European service – the German and French CL-289s have flown 1400+ sorties over the
Balkans since late 1998. Launched from sites in Macedonia, thus far only four CL-289s have been lost.
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The Flying 'Peanut' – Canadair's Contra-rotating CL-227 Sentinel
Both CL-89 and CL-289 took a decade from design to deployment. In between, Canadair began working on an
even more radical concept. The result was the rotary-wing CL-227 Sentinel. The central
'stack'
(as Canadair called it) consists of the gearbox for the contra-rotating propellers, flanked by
upper and lower lobes containing powerplant, fuel, and sensors. Proof-of-concept prototypes (1977) were powered by
17kW Wankel piston engines but the technology-demonstrators (1981) were powered by 24kW (later increased to
38kW) turboprops. Sea Sentinel, first flown in 1988, would later be tested aboard US Army, Coast
Guard, and Navy vessels.
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Canadair Eclipsed – Bombardier and the Future for Canadian UAVs
The introduction of the CL-289s into Franco-German service had been handled by Aérospatiale and Dornier
GmbH – the latter company has also coordinated the recent upgrade package for the CL-289. Failure to
place CL-289s in CF service can be attributed to ideology – Canadair had been
'rescued' by a Liberal government and the Mulroney Tories would support it no further.
Bombardier, the new owners of Canadair, has had little more success marketing UAVs. No third-generation
Midge has appeared. Instead, Bombardier has placed all its eggs (or, rather, peanuts) in the rotary-wing
basket. The CL-327 is a very clever 'least mod' development of the CL-227 [3] but it is
a development – no new ground is being broken here. The CL-327 may still be able
to carve out a niche for itself. The Guardian distinguishes itself from the UAV pack by its
compact arrangement and vertical take-off/landing – particularly important for shipboard operations. The US Navy
has tested the CL-327 although without committing itself. Ultimately, the Guardian's success may depend
upon a domestic order.
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[1] The CL-89 was jointly funded by Canada and Britain with Germany joining the project in 1965. Designated
AN/USD-501, CL-89s began entering service in the early 1970s. As shown in the photos, the CL-89 was launched from
the back of a 5t truck. A British 2,065kg booster rocket fired the CL-89 along a short launch rail. Once
the vehicle achieved flying speed the booster was jettisoned and a tiny 57kg thrust Williams Research WR2-6 turbojet
took over propulsion. The CL-89 followed a pre-programmed flightpath, scanning its target area
with an infrared linescan camera before relaying data back to a ground station for processing. The IR camera
was turned on at the last moment to avoid detection of the relay signals. An optical camera was also fitted. When the
mission was complete, the CL-89 landed by parachute.
[2] The CL-289 is an enlarged, faster version of the Midge and operates in very much the same way. CL-289s
first became operational with Germany in 1990, and with France two years later. French CL-289s are called PIVER
(Programmation et Interprétation des Vols d'Engins de Reconnaissance)
although , properly, this refers only to the ground station. In 2002, Italy's Esercito replaced its
old CL-89s with CL-289s.
[3] The CL-327 was feasible, in part, due to advances in rotor blade technologies. To keep its development
costs managable, Bombardier needed to re-use the CL-227's central 'stack' unchanged. Rotor blades
were to be longer but mounted no further apart vertically. In order that the contra-rotating rotor 'discs'
not collide, each individual blade needed to be stiffer. Testing suggests that this evolution has been
successful. A CL-327 prototype was lost during US Navy tests but the 'fix' was simple and the
accident was unrelated to flight dynamics.
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