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Summary

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SensorCraft UAVs

At the turn of the millennium, the U.S. Air Force Research Laboratory AFRL (Air Force Research Laboratory) located at Wright-Patterson base in Ohio began exploring the idea innovative approach in building reconnaissance aircraft. Basically it was a completely opposite approach than previously used: instead of the proposed aircraft were installed in it and all necessary sensors, first had to choose a mix of sensors and the plane itself, so to speak vyskladan� be around him. A similar approach has already been successfully applied in earlier U.S. program AX, which was fighter A-10 Warthog built around a 30 mm cannon GAU-8 / A. In this case, the philosophy went even further. Sensors not only be useful load, but should become an integral part of the hull directly. This would give the machine is built big, heavy and bulky radar antenna with the enormous power without unduly increase the overall machine weight, drag, or the total range. The same time that the antenna while the hull is built into the structure given, so that was basically unrestricted 360 degree view of the researched area. This would replace the conventional disc or pritrupov� trucks, machines used in the current AWACS and JSTARS category. The largest aircraft manufacturers were invited to submit their proposals. Lockheed Martin to promote his concept of the beginning of a relatively conventional solutions in the form of large aircraft, gliders with wing span up to 60 meters. The radar antenna should be mounted on the sides of the fuselage.

Later, however, showed that the conventional concept has several weaknesses, and so was replaced over time flying wing with high aspect ratio and a similar range, with a maximum takeoff weight fluctuated at around 40 tons. At that time the company received Northrop Grumman, Boeing and Lockheed Martin initial contracts worth several million dollars to demonstrate the sub-critical technology in the period 2001 to 2003. Lockheed Martin to work with others also benefit from ongoing technological activities, such as the project UMAC (Ultralight Multifunction Airframe Concepts), who participated at Bell Helicopter, Raytheon and Southwest Research Institute. Smaller contracts were the engine manufacturers to work on advanced solutions, particularly on magnetic bearings, eliminating the need for lubricants or integrated starter. The resulting engine should be compared with the kinds of time available to 35 percent less fuel to achieve the projected range and takeoff weight.

Closest to the topic seemed to company Northrop Grumman, which has already worked on a flexible Conformal radar antenna under LOBSTAR (Low-Band Structural Array). This should form a sort of flat panel (with the possibility of shaping the airfoil), the radar waves to rely solely on the front of the open edges. The fact that it was a low-frequency system itself can be relatively easy radar beam directed to the sides and cover the very large area of \u200b\u200bground and aerial targets. Similarly, the incorporation of electronics into a sandwich composite structures allow the antenna used alone as the wing surface and thus save a significant part of parasitic weight. Although first draft based on quite logically developed by means of RQ-4 Global Hawk, will soon also move the development process to the final form of a flying wing.

The resultant design wing span of 62.5 meters with a maximum take-off weight at 57 tons is quite similar to the initial study, B-2 bomber, but with less duration. Drive procured two jet engines that allow life in the air up to two days without refueling in the operating height of 18 km. Due to the large margin should be even in this case the wing maximum flexibility, while its outer part is also located high-frequency radar to detect aerial targets at great distances. Conformal X-band radar, serving primarily the accurate detection of targets located closer to the body leading and trailing edge. Considerable bending wings and thus substantially change the whole shape of the radar antenna must be compensated by a very powerful computer software with the capacity of the order of teraflops. The award of contract by Northrop Grumman built the scale model of the wing and fuselage central part of the overall bending tests and structural integrity.

Although at first glance it may seem that Boeing study is another step project development Diamond is not true. It took a similar study of the wing joint, named EX , developed by Boeing engineers before the merger with McDonnell Douglas company. At that time it was envisaged as a potential successor to the naval aircraft Grumman E-2C Hawkeye. Radar should be placed, or should form front and rear wing, but leaving room for mechanization and maneuvering areas. Originally formed a central part of the aircraft fuselage with twin engine nacelles, located on the outer sides.

Boeing named his concept AASS (Autonomous Airborne Surveillance System) and its final form is the model 1076-410E. He has only one central torso extension, which also contains a fuel system. From it extends backwards and upwards relatively thin hull girder that holds the inner end of the rear wing. Size of the aircraft is approaching B-2 bomber with a range of 50 meters, but compared to the competition has a slightly higher maximum takeoff weight at 61 tons. Most of it is fuel. Unlike the competition, the concept of joint wing chosen mainly because the sensors can be placed away from other interfering elements such as onboard navigation and control electronics or engine.

Development of sub-technologies for this type of aircraft for which the general term SensorCraft caught on, now underway. AFRL aim here is to tighten the necessary technology to the point where it will be possible to start developing the actual flight demonstrator and subsequently operational weapon system. It was originally envisaged potential starting work on a prototype for the period 2009 to 2013, the serial version could come into service sometime after a row in 2017. Their skills and ultimately the size and nature is too close to the philosophy and Aars, albeit using different approaches and solutions. Maybe so still we get the “perfect” national reconnaissance and surveillance system, but the final decision to initiate the development of sharp yet been taken. Interestingly, the study of aircraft SensorCraft in principle not subject to any special degree of confidentiality and so are the eyes of the general public, which was twenty years ago absolutely unthinkable.

Sources

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