Foo Fighters

by Brian Dunning
February 20, 2024

World War II saw more more aircraft and flyers take to the air than any other time in history. And so, consequently, it also brought more of all the other things that go along with that. New airplane types were introduced faster than ever before. We had more plane crashes. More midair collisions. More speed records. More hotshot pilots. More airborne weaponry and technology, and more anti-aircraft weaponry and technology. Everything there is to say about aeronautica, World War II saw it happen at a level unprecedented in history; and so by definition, that includes pilot reports of UFOs.

The term "UFO" didn't exist yet — that didn't come into use until the 1950s, when it became clear that "flying saucer" didn't always apply. And even "flying saucer" didn't come around until 1947, two years after the war. With no term yet in existence, but an unprecedented number of aerial encounters, what did the pilots call them? Well, many of them used the term "foo fighter". The origin of that term doesn't matter too much; that's a whole separate subject. The leading candidates are that it was borrowed from Bill Holman's pre-war comic book series Smokey Stover (1935-1972) about firemen, which used the term Foo Fighter a lot; and that it was a shortened version of FUBAR, an acronym for something Skeptoid's non-explicit tag in the RSS feed prohibits me from elucidating.

Most histories credit the American 415th Night Fighter Squadron with being the first to popularize the term, and it soon caught on as a catch-all phrase for anything weird that any Allied pilots saw in the sky. The 415th flew heavy twin-engine attack aircraft, mostly at night, so they were well positioned to be among the first to report multiple weird lights in the sky as they flew. And weird lights in the sky is what the majority of foo fighters were, at least earlier in the war, until distant objects began to be reported during the daylight as well.

Some of the more famous reports involved whole groups of white, yellow, orange, or red fireballs, often keeping pace with an aircraft, sometimes maneuvering around it or outpacing it. Pilots who tried found it impossible to chase them without being outmaneuvered. Sometimes they would disappear as quickly as they'd appeared. The foo fighters never hurt anyone or presented a danger, but that didn't keep some pilots from being pretty alarmed by them.

Far from being purely a phenomenon reported by Allied forces over Europe, it turns out that foo fighters were also reported by German, Russian, and Japanese pilots during the war. Whatever they were, they seemed to be everywhere. So now we're going to go through a list of a number of possible explanations that have been put forward, starting with:

1. St. Elmo's Fire

St. Elmo's Fire was the most commonly offered explanation for foo fighters. First of all, it's a real thing, and it is "lights in the night sky," so it's not surprising that armchair experts back in the States suggested it as an explanation.

The problem is it's not a very good one. While the pilots were reporting anything ranging from points of distant light that moved around to flaming balls of light that followed their planes, St. Elmo's Fire manifests very differently. You can go to YouTube and watch videos of it. What you'll see, whether it's coming from the nose of an aircraft or the mast of a sailboat, are periodic flashes of what look like little purple lightning bolts. They're not static; they're not round balls; they're not warm colors; they don't fly around and follow your airplane. They're cold, instantaneous, little purple lightning flashes that immediately disappear. No cogent person would witness St. Elmo's Fire and describe a flaming ball of light flying around your airplane.

I'll acknowledge that of all the foo fighter reports from WWII, a very few may well have been St. Elmo's Fire. But as far as it being a decent match for any significant number of the reports, no.

2. Flares

I do believe that flares likely were behind some number of foo fighter reports. Illumination flares would indeed look a lot like what the pilot reports describe. Planes are always pitching, yawing, and rolling; and when a static object like a battlefield parachute flare is in your field of view, it will appear to be moving around. This is called the autokinetic effect, and it's a very common (and very compelling) optical illusion. I've experienced it myself, when I was standing on the deck of a ship at sea and I insisted to my friends that a light on the horizon was darting around in a seemingly impossible way, because my brain simply could not accept that it was me who was moving on the rolling ship deck, and that distant star (or lighthouse, or whatever it was) was actually static. The autokinetic effect undoubtedly explained some percentage of foo fighter reports, as during wartime there would have been lots of lights in the air as well as on the ground.

3. Battle Fatigue

This was kind of a lame attempt by the grayheads back in the States to rationalize the foo fighter reports. But, the fact is that people do sometimes fall asleep at the wheel, and pilots do sometimes fall asleep at the stick. A quick microsleep, a quick dream, and yeah sure why not: you might well think you saw something out there. It's a sufficiently reasonable explanation that probably did apply to a small number of reports, but can hardly stand as the solution to the whole phenomenon.

4. Actual Nazi Weapons

Many authors have put forward the suggestion — as did people at the time — that Nazi weapon systems like the V-2 ballistic missile and the rocket-powered Me-163 Komet fighter plane were the foo fighters. If seen at night, these would indeed have presented as speeding fireballs zooming past. It's possible that such rockets were seen and not correctly identified by pilots some number of times. However, the Komet is not known to have ever flown at night, and the V-2 flight profile would have made it hard to spot. It launched at an angle of 47º on its way up to a 300,000-foot apogee; its engine cut off after only one minute, and most of its flight was completed unpowered.

5. Speculative Nazi Weapons

The most interesting proposal, and also the least plausible, was suggested by Renato Vesco, an Italian UFO writer. His claimed background is that he was an aeronautical engineer before the war, and during the war he worked with the Nazis in Italy developing secret weapons; and further claims that after the war he was a secret agent for the Italian Air Force. As Vesco was born in 1924, I found that highly dubious. He would have been 15 years old when Italy entered the war. And luckily, I'm not the only skeptic to feel that way. Writing on the Danish Skeptica website in 2004, Kevin McClure contacted some Italian colleagues who knew Vesco personally (he is since deceased). Vesco was simply an Italian aeronautical engineer with an interest in UFOs. He wrote several books about them, a few of which have been translated in English.

In his books (published after WWII as he would have been too young during the war to know much about the subject), he asserted that the foo fighters were Nazi secret weapons called the Fireball (Feuerball) and the Kugelblitz. Since he wrote about them, a certain population of conspiracy theorists and UFOlogists have embraced them as unassailable fact, despite the fact that the only person in history to have known about them was a young man who is known to have falsified his background and was too young at the time to have possibly had any knowledge of them. But, since some believe they are the explanation for foo fighters, I will include them today.

His descriptions of the Fireball were light on specifics, but he said it was "enormous looking." It was circular and armored and looked like a tortoise shell. It was powered by a turbojet engine. It spun around, spewing "a great halo of luminous flames" — thus being a match for the reported foo fighters. It was pilotless and when launched (he did not say how) it would home in on the heat signatures of enemy aircraft (he did not explain how it discriminated friend from foe) and fly close to them, but not close enough to hit them (he did not explain how). And then it would attack the radars of the enemy planes (despite very few planes being equipped with radar in that day):

The fiery halo around its perimeter — caused by a very rich fuel mixture — and the chemical additives that interrupted the flow of electricity by overionising the atmosphere in the vicinity of the plane, generally around the wing tips or tail surfaces, subjected the H2S radar on the plane to the action of powerful electrostatic fields and electromagnetic impulses (the latter generated by large klystron radio tubes protected with special antishock and antiheat armor).

A neat feature is that it was double-hulled, and if a bullet penetrated its outer hull and made contact with the inner hull, that would complete an electrical circuit which would trigger the Fireball to escape the vicinity by shooting straight up in the air.

Of the Kugelblitz, Vesco said less. It seemed to be broadly similar to the Fireball; however it may be telling that Kugelblitz translates to "lightning bullet". Kugelblitz was also the name given by the Germans to an actual weapon, a self-propelled anti-aircraft artillery vehicle built on the chassis of a Panzer tank. However, none of this really matters, since the Fireball and Vesco's version of the Kugelblitz were unquestionably fictional. We can be assured that neither is the explanation for any foo fighter sightings.

6. The Same Things that Explain Today's UFO Sightings

In all probability, foo fighters were the same things that fool pilots today. Most of these are celestial objects, most often the planet Venus. I hate how incredibly dismissive this explanation sounds, and it has never sat well with me; but the fact remains that when investigators do manage to track down exactly what a pilot saw, it turns out to be Venus more often than anything else. And then we have the other celestial objects: stars, shooting stars, other planets, you name it.

After that we have aerial clutter — all the other things in the sky, and during WWII there would have been plenty of these. Other aircraft, artillery shells, tracer bullets, flak explosions, blimps and balloons, the list goes on. Distant lights on the ground also continue to fool pilots today. Given apparent motion by the autokinetic effect, the motion parallax illusion, and other effects, any and all of these do fool pilots into thinking lights in the sky are chasing them and maneuvering around them. The UFO literature is full of such cases. And these were mostly very young pilots, pioneers in what was still a very new field that nobody had much experience with yet.

The takeaway from a story such as this is that there was certainly not "one single explanation" for the foo fighters. Many pilots in many places in many circumstances saw weird things they didn't immediately identify; and although we have insufficient data to make a good identification for any specific case, they probably all have multiple possible explanations. Our error would be to look for a single explanation for all of them. Some were probably celestial objects, some were airborne clutter, some were lights on the ground, some were probably nothing more than optical illusions.

The big question that many will want answered is whether any of the foo fighters required an extraordinary explanation: were they something truly exotic? And the answer is that we have no reason to suspect that. Unidentified doesn't mean positively identified as anything. So for now, we're going to leave the foo fighters where we found them — as aerial footnotes to history's biggest war, minor mysteries and nothing more. "We don't know" rarely means we've eliminated every possible prosaic explanation; more often, it means we haven't eliminated any of them.

By Brian Dunning
Follow @BrianDunning