The satellite technology is held with the dev countries. The satellites are expensive devices and require continuous maintenance. However, UAVs due to their low cost and other obvious advantages have answered countries, which are without satellite technology.
9. Definitions. Unmanned aircraft is powered aerial vehicle that does not carry human operator. They use aerodynamic forces for lift and a propulsion system. The ground/airborne controller direct UAVs or they are pre-programmed. On the basis of their control system, UAVs are classified into two broad categories:-.
a. Drone. It is pilot less aircraft, which obeys the commands stored in the memory of its guidance system.
b. RPV. It is remotely piloted vehicle which remains under the command of a ground based pilot / controller.
c. UAV. Unmanned Air Vehicle is a common name given to drone / RPVs since the two guidance systems frequently overlap. An RPV on long distance flight becomes a drone as soon as it is out of radio contact with the ground station and operation on its preprogrammed automatic pilot, which will also guide it to the ground station. Many drones on the other hand are launched on a pre-programmed course but land under ground control.
d. RPH. Remotely piloted helicopter.
e. UMA. Unmanned aircraft.
10. UAV Classifications. Anx A. Another classification system used by the US is based on the gen caps of alt, range and endurance. This system emp three broad cats of Tier I, Tier II or Tier III, with sub-categories such as Tier II plus and Tier III Minus. UAVs/RPVs can also be classified according to range of operation as under:-.
a. Range of Op .
(1) Close Range. Up to 30 Kms and has 1 to 6 hrs flying endurance.
(2) Short Range. Up to 150 Kms and has 8 to 12 hrs flying endurance.
(3) Med Range. Up to 650 kms and has 12 to 16 hrs flying endurance.
(4) Tac UAVs. Having range of more than 650 kms.
(5) Strat UAVs. Having range of 3000 kms.