A case for a ‘sometimes’ UAV

 - June 14, 2007, 9:13 AM

Unmanned aerial vehicle (UAV) technology is arguably the fastest growing aspect of present-day aviation. Unmanned combat aerial vehicles are revolutionizing the conduct of military operations, and some law enforcement, border security and other civil activities are being undertaken by UAVs as well. Very small hand-launched models are aiding soldiers, while police and firemen will soon be able to search inside buildings where danger lurks.

Terrorists in Yemen have been attacked from the air by Hellfire missile-toting UAVs, while such aircraft will soon patrol parts of Australia’s extremely long coastline. Crime in South Africa has long been tackled by UAVs operating in civil airspace, while long lonely borders in many countries can be patrolled remotely.

However, to avoid deploying military and civilian UAVs to faraway places as cargo in transport aircraft, it would be easier if they could be flown there direct. But given the limited experience of flying UAVs along international airways, many countries are reluctant to approve such movements through their airspace. Consequently, there is a growing interest in optionally piloted UAVs (OPUAVs) that could be ferried by crews around the world with fewer clearance problems.

Fitting a cockpit and flight controls would seem to be defeating one of the key purposes of UAVs, namely to simplify the aircraft’s design, reduce its size and control one or more from the ground. But converting an aircraft designed to be piloted into an “occasional UAV” is a solution that is being actively promoted by Diamond Aircraft. This is one company that sees the potential of OPUAVs and it has been busy demonstrating a contender to potential customers in Europe and the Arabian Gulf.

The new Opale 42 platform is based on the Diamond DA42 all-composite aircraft powered by two economical Thielert Centurion 1.7 diesel engines and has been developed in consort with Rheinmetall, the German automotive and defense company, as well as some surveillance equipment suppliers. The Opale 42 carries a 1,100-pound sensor payload and has an endurance of some 30 hours. Carrying a safety pilot and a local military officer, the aircraft was demonstrated during the recent IDEX show in Abu Dhabi, transmitting live video scenes direct to Rheinmetall’s ground control station on the exhibition grounds.

The system makes use of the same antenna and ground station that supports the KZO UAV now being produced by Rheinmetall for the German army. Diamond is also working with Austria’s Scotty Group to facilitate the transmission of live video via satellite communications.

Other OPUAV Programs
The United Arab Emirates has long taken a keen interest in UAVs, and a few years ago Abu Dhabi-based Gamco Special Projects (then part of Gulf Air) proposed several different surveillance UAV designs, including the GRS 200 medium-altitude long-range model powered by a single ducted fan engine. This 49-foot wingspan OPUAV was to have been manned or unmanned, but the GRS 200 along with other innovative designs did not survive the contraction of Gulf Air after ownership of the airline was transferred to Bahrain and Oman.

Separately, the Eagle high-wing, single-engine light aircraft featuring a large canard was originally designed, certified and produced in Australia. The program was subsequently acquired by Composites Technology Research Malaysia (CTRM), which has worked with its Excelnet subsidiary and BAE Systems to develop
the Eagle ARV (airborne reconnaissance vehicle) system.

Each ARV system comprises three highly maneuverable Eagle 150B aircraft, a ground control station and a remote receiving station, with the aircraft being operated either manned or unmanned. One system has been acquired by the Malaysian government and CTRM is promoting it not only for military surveillance but also for such civilian operations as coastal and border patrol, aerial survey and for monitoring the environment.

In the U.S., Scaled Composites produced the piloted but optionally unmanned Proteus aircraft some years ago. And Boeing is said to have offered an optionally manned version of the Gulfstream G550 to meet the U.S. Navy’s Broad Area Maritime Surveillance UAV system. Boeing’s OPUAV contender is competing with the Global Hawk and a derivative of the General Atomics Predator-B UAV proposed by Lockheed Martin.

Meanwhile, the SkyRaider and SkyWatcher designed and built by Maryland-based Proxy Aviation Systems are intended for unmanned/occasionally manned operation, specifically to enable them to be flown through national airspace, rather than through restricted corridors, or delivered by a cargo aircraft. The Proxy designs have been flown with a safety pilot on board but also completely autonomously as UAVs.