A NATO AWACS surveillance plane is parked at the Romanian Air Force 90th Airlift Base, in Otopeni, Ilfov, Romania, Jan 17, 2023. (PHOTO / INQUAM / FILE / GEORGE CALIN VIA REUTERS)

BRUSSELS - NATO will place its ageing fleet of AWACS surveillance planes, in serrevice since the Cold War in the 1980s, with a militarized version of the Boeing 737 commercial jet, the alliance said on Wednesday, in a deal likely worth billions of euros.

Acting like a flying radar tower, the AWACS (Airborne Warning and Control System) jets with the distinctive, nine-meter wide radomes on their backs have been NATO's eyes in the sky since 1982.

With their rotating radar, the current modified Boeing 707 jets can detect aircraft at a distance of more than 400 kilometers.

They are capable of monitoring an area of some 300,000 square kilometers, a territory the size of Poland, according to NATO, and can also detect ground targets such as ships.

To replace the old AWACS jets, NATO aims to purchase six Boeing E-7 A Wedgetail planes, with the contract to be signed in 2024 and the first jet ready for operational duty by 2031.

Surveillance and control aircraft are crucial for NATO's collective defense and I welcome allies' commitment to investing in high-end capabilities. This investment in state-of-the-art technology shows the strength of transatlantic defense cooperation as we continue to adapt to a more unstable world.

Jens Stoltenberg, NATO secretary-general

"Surveillance and control aircraft are crucial for NATO's collective defense and I welcome allies' commitment to investing in high-end capabilities," NATO Secretary-General Jens Stoltenberg said.

"This investment in state-of-the-art technology shows the strength of transatlantic defense cooperation as we continue to adapt to a more unstable world."

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The alliance did not specify why it chose to replace its fleet of 14 AWACS planes with only six Wedgetail jets, but it said the new aircraft would have better capabilities and be more expensive than their predecessors.

The United States, Britain and Türkiye also either fly the Wedgetail or plan to operate it.

Based at Geilenkirchen airbase in Germany, the AWACS fleet has been widely used for NATO surveillance missions along the alliance's eastern flank in the wake of Russia's special military operation in Ukraine.

In the past, the aircraft supported NATO missions in the Balkans, Afghanistan and Iraq, but also events such as the 2006 World Cup in Germany and summit meetings.

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In a conflict, the AWACS planes can not only provide a radar picture for allied fighter jets, ships and control centers, but also direct NATO combat jets to their targets.

The aircraft, one of the few assets NATO actually owns, are staffed with multinational crews from 19 of the 31 allied nations.