Foo fighters

Balls of light that Allied night fighter crews said followed their planes over Germany from November 1944.

TIME reported in January 1945 that American night fighter pilots flying from bases in France described fireballs trailing their aircraft at night over Germany for over a month. The pilots took it for some new weapon of psychological war and gave it the name foo-fighter. Wikipedia says the name came from an American night fighter squadron, and that the term was soon used for any UFO sighting of the period.

Air & Space / Smithsonian magazine retells one report from November 1944, by the crew of a Bristol Beaufighter: Edward Schlueter (pilot), Donald J. Meiers (radar observer) and Fred Ringwald (intelligence officer). They were flying north of Strasbourg along the Rhine when they saw eight to ten orange lights to their left, moving fast. Neither the plane's radar nor ground control picked anything up. The lights vanished when Schlueter turned toward them, then showed up farther off. Task & Purpose recounts how war reporter Robert C. Wilson spent the last day of 1944 with that squadron in southern France.

Gerald K. Haines's 1997 history for the CIA says the OSS, worried the lights were secret German or Japanese weapons, looked into such reports, found nothing concrete to show the enemy had built them, and often dismissed the reports as crank material. Brian Dunning, on the Skeptoid podcast in 2024, notes that pilots on the German, Japanese and Russian sides reported them too, and goes through the explanations people have offered.