radar picket

A radar picket is a radar-equipped ship, submarine, aircraft, or vehicle used to increase the radar detection range around a force to protect it from surprise attack. Often several detached radar units encircle a force to provide increased cover in all directions. Radar picket ships first came into being during the second world war to aid in the advance to Japan. As they were the nearest ships to the Japanese airfields, and hence the first seen, they were often heavily attacked by kamikaze aircraft. Formerly, the United States Navy employed radar picket ships such as the USS Hissem (DER-400) to extend the DEW Line seaward. The designation DER indicated "Destroyer Escort Radar picket ship." DERs carried no armaments, but the cannon were left in place to retain their appearances as warships. The British Royal Navy built a specialised class of radar picket frigate; the Type 61 or Salisbury class.
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Any ship, aircraft, or vehicle, stationed at a distance from the force protected, for the purpose of increasing the radar detection range. 1/11/68

Navire, aéronef ou véhicule stationnant à une certaine distance de la force à protéger, dans le but d'augmenter la portée de la détection radar. 1/11/68