The use of 'exclusive economic zones' (EEZ) has become fashionable in recent years. Countries have started to understand the many threats on their maritime natural treasures, and wanted to draw a line that will make it easier to protect them.
In order to protect something that belongs to a country, but is located a good distance from the shore, you need surveillance - persistent surveillance.
Maritime surveillance requirements are demanding specific capabilities and performance, such as mission endurance and flight profiles.
Until recently such missions were performed exclusively by aircraft - some dedicated to the maritime surveillance mission, while others used off-the-shelf transport planes modified for the job.
These missions typically demand coverage of very wide areas, monitoring extensive maritime traffic, as well as deployment in unexpected conditions in response to emergencies or on search and rescue tasks.
Therefore, the need for efficient development of a maritime situational picture is critical, enabling the deployment of the few available aerial assets to cover only those areas or targets of significance.
The introduction of unmanned air systems (UAS) is changing this paradigm, removing the limitations that have restricted manned missions while introducing new capabilities which significantly enhance operational flexibility and efficiency of maritime control.
This capability has become specifically important in recent years, as countries are required to cover growing maritime areas claimed by EEZ.
These can be located up to 200 nautical miles from a country's coastline or furthest-away island. In the case of India, for example, such an area covers a huge expanse of the Indian Ocean, bordering Indonesia in the east to Somalia in the west.
A country cannot cover such vast space from its coastal radar stations, nor can it commit manned patrol flights to cover the entire area.
At Aero-India 2013, Israel's Elbit Systems is introducing its newest and largest UAS, the Hermes-900, in a configuration adapted for maritime missions. This UAS can carry payloads of up to 350kg.
In the maritime configuration the payload suite includes maritime surveillance radar, an electro-optical multi-sensor payload and electronic surveillance systems. It has the endurance to cover vast ocean areas, redundant line-of-sight and satellite communications links and radio relays - enabling the operator to 'talk through' to vessels at sea.
The Israeli company says that the aerodynamic efficiency of the Hermes-900 enables frequent changes in flight profiles, along with visual identification of vessels at sea in addition to the inverse synthetic aperture radar capability.
Satellite communication enables it to fly to mission areas at extended ranges as far as 1,000 nautical miles from shore.
Elbit also says that a unique capability supported by its command and control systems is the ability to control two UAS simultaneously from a single ground control station, using the redundant data-links.
This has a significant effect on the assets, manpower and operating cost required, as well as in improving the efficient utilisation of UAS, that can cover a wider area or run dense surveillance patterns.
There are strong indications that UAS are going to replace many of the manned platforms currently used for all types of maritime patrol missions.