Cloaking...

[BuddyB309]

hhhmmmm.... i dont know. sounds fishy.

[KenWittlief]

during WW2 American aircraft that hunted submarines had an effective cloaking system.

It would measure the brightness (and maybe color?) of the sky behind the aircraft, and lights on the front of the plane matched the sky.

From a distance it made the planes very difficult to spot visually. By the time the plane was close enough for a submarine to spot it, they did not have enough time to dive and escape.