In Thailand, the NRDO (Naval Research and Development Office) recently revealed it had developed Narai 3.0, a small quadcopter UAV for use on coastal patrol boats as well as on land. Equipped with day or night-vision vidcam, Narai 3.0 has a max payload of one kg (2.2 pounds), can stay in the air for 30 minutes at a time and operate 2,000 meters from the operator. Top speed is 60 kilometers an hour The UAV itself, costs $6,500. The UAV with controller and day vidcam costs $11,400, and with night-vision camera $14,700. This UAV is being used for coastal and border patrol to detect smugglers (people, drugs and other contraband) and illegal logging. Narai has GPS for flying pre-programmed patterns but the controller can take over at any time. The military has bought over 80 of the Narai 3.0. What is most unusual about the Narai 3.0 is that similar commercial quadcopters can be bought for under two thousand dollars. Moreover, there are quadcopter component suppliers that sell airframes, batteries and control electronics that enable anyone to mix and match components and built their own UAV. Components for one of these with the same performance as Narai 3.0 cost less than a thousand dollars and some of the airframes available look much like the Narai 3.0.
Why does the Narai 3.0 cost three times what a commercial model goes for? Part of it is prestige. Thailand has been buying commercial UAVs since the 1990s and used them a lot. The latest Thai acquisition is four Israeli Hermès 450 UAVs that arrived in 2018. These were ordered in 2017 as part of a deal that cost $30 million and included training, tech support and some high-end sensors. Thailand has been using Israeli UAVs since the 1990s when Searcher UAVs were ordered specifically for border patrol. These were eventually retired and replaced by Searcher 2 and Aerostar UAVs. Searcher 2s were ordered about a decade after the first Searcher 1s. The new model entered service in the late 1990s and was basically an upgrade of the original Searcher. Searcher 2 is a half-ton aircraft with an endurance of 20 hours, max altitude of 7,500 meters (23,000 feet), and can operate up to 300 kilometers from the operator. It can carry a 120 kg (264 pound) payload. Thailand has also purchased and used the American Raven micro-UAV for use by the army and border patrol. At the same time, Thailand had been developing its own UAVs.
Narai is the first quadcopter for Thailand but armed forces worldwide have been using commercial quadcopters for nearly a decade. Thailand is also developing a VTOL (Vertical Take Off and Landing) model that is similar to one the Chinese navy was seen using this year. In early 2019 a Chinese destroyer in the South China Sea was seen using a new VTOL UAV off its helicopter deck. That VTOL UAV was easily identified as the Chinese made SD40, a UAV offered for sale to commercial users for operating over land or sea. The SD40 is small, only 40 kg (88 pounds) and apparently intended for naval use on smaller ships (corvettes and patrol boats) because Chinese destroyers used larger manned and unmanned helicopters due to their larger payloads, longer flight time and better stability in high winds (as are frequently encountered at sea). But the SD40 is a hybrid quadcopter/fixed-wing propeller-driven UAVs. The SD40 is a triple fuselage battery-powered quadcopter (for takeoff and landing) that switches to a gasoline-powered rear propeller (in the larger main fuselage) driven fixed-wing aircraft once aloft. The two smaller outer fuselages each contain two of the quadcopter rotors and batteries for takeoff, landing or hovering. The 3.7 meter (11.8 feet) fixed-wing provides plenty of lift and stability for level flight and a max speed of 180 kilometers an hour. Cruising speed is 100-140 kilometers an hour. Max payload is 6 kg (13 pounds) which will handle a wide range of day/night vidcams or even a lightweight radar (SAR or lidar). SD40 has an endurance of up to six hours (depending on how much hovering is done). Max altitude is 5,000 meters (16,000 feet) although normal operating altitudes are 1,000-3,000 meters.
These VTOL designs are becoming more popular because they can operate off smaller ships and patrol boats and have better endurance and stability (in high winds) than heavier helicopter UAVs. The U.S. Navy gained practical experience in this when they used (and still use) the 1.4 ton MQ-8B Fire Scout helicopter UAV. The MQ-8B lacked the stability in bad weather and other conditions that larger helicopters can handle. The Navy bought 29 MQ-8Bs after 2009 and accumulated over 12,000 flight hours with it. The basic design was good, but it was too small.
In 2013 the navy transferred the control hardware and software of the MQ-8B to a larger helicopter (a navalized Bell 407) to become the 2.7 ton MQ-8C. This provided the greater stability, endurance and triple the payload of the 8B version. The 8C model entered service in mid-2019 and 38 are being procured to complement about 24 MQ-8Bs in service. The U.S. Navy is using both models on the 3,200 ton LCS type ships and other smaller vessels.
China has more options when it comes to different types of UAVs because it has the largest number of UAV developers/manufacturers in the world and dominates the quadcopter market. The Chinese Navy has been seen testing a large variety of these commercial designs, including some similar to the MQ-8B. China also has a larger number of small warships and patrol boats than the United States and many of these can accommodate a smaller VTOL UAV. The Thai navy could call on China to share its knowledge of naval UAVs and recommend which Chinese UAVs to purchase. Instead, the Thai Navy choose a more expensive approach, which the navy has done before.