Apparently, the UAE (United Arab Emirates) is buying two, or possibly three, more Erieye AEW (airborne early warning) systems, to be carried by Saab 2000 aircraft. Both Erieye and the Saab 2000 are manufactured by the Swedish firm Saab. This latest sale is to an unnamed customer and the most likely buyer is the UAE, which already has four Erieye aircraft and has indicated a need for more to deal with the growing threat from Iran. The UAE also backs a wider program to link ground and air-based surveillance radars by GCC (Gulf Cooperation Council) states (Bahrain, Kuwait, Oman, Qatar, Saudi Arabia, and the UAE) into a cooperative surveillance network that would provide all GCC members with better information on that is going on in the skies over their nations and the Persian Gulf in general.
The UAE ordered their first two Erieye AEW systems in 2009 and one (later two) of the then new Globaleye systems in 2015. Globaleye was still in development when the UAE placed its order. Given the history of reliability Saab had earned, it seemed a good idea to be first in line. Globaleye completed development and testing in 2019 and the UAE received the first one in April 2020.
Globaleye uses the upgraded Erieye ER radar which can detect aircraft over 400 kilometers distant. Another new feature is the ability to detect ballistic missile launches as well. The first two UAE Erieye systems were carried in the 13 ton Saab 340 airliner, which had a cruising speed of 290 kilometers an hour and was able to stay in the air about five hours per sortie. The latest UAE order will carry Erieye/Globaleye in a larger version of the Saab 340 called the Saab 2000. The Saab 340 ended production in 1999 while the 2000 model is still being built. Most of the 500 or so 340s and 2000s are used by regional airlines.
Globaleye includes a maritime search radar as well as upgraded AEW radar. Since a combined AEW maritime search system is heavier and needs more space, as well as operating farther from land, Globaleye is carried in a larger aircraft. Initially, this was the Canadian Global 6000, a 42 ton twin-jet aircraft with a cruising speed of 900 kilometers an hour and an endurance of about ten hours. Like the basic Erieye system, Globaleye can be carried in any number of similar twin-engine jet or turboprop aircraft.
The Erieye system is built around an Active Electronically Scanned Array (AESA) radar which consists of thousands of tiny radars that can be independently aimed in different directions. This is similar to the AESA radar used on the American JSTARS aircraft, a system that could locate vehicles moving on the ground. The Swedish AESA is cheaper because it's built like a long bar, mounted on top of the aircraft. This means the radar can only see, in a 120-degree arc, off both sides of the aircraft. A 60-degree arc in the front and back is uncovered. The Erieye ER radar can spot large aircraft out to nearly 500 kilometers, and more common fighter-sized aircraft at about 400 kilometers.
The UAE uses these aircraft to manage air campaigns, including the one underway in Yemen since March 2015. The primary use for UAE AEW aircraft is to deter an attack by Iran.