Many of the greatest air battles in history took place during World War II. There are also numerous unexplained sightings of anything from Foo Fighters to UFO’s that are still being debated. The story of the B-17 “Ghost Bomber” however, is inarguably unique.
The investigators, who were dying to finally board the inexplicable self-landing bomber, did not find the answers they were looking for onboard but found something they were not prepared for. You’ve never seen anything like this before!
On November 23, 1944, in an allied base in Cortonburg, Belgium, an event occurred which has not been completely understood to this day. An American B-17G appeared in the sky over the base and seemed to be heading right into three allied anti-aircraft gun positions. The crash seemed inevitable.
From the ground, the soldiers observed that the bomber’s landing gear was down and due to its erratic flying patterns, they assumed that the plane had suffered damage or that the crew had been injured. It was coming in hot, and all they could see was 35,000 pounds of metal heading right towards them. They fell to the ground and prepared for impact, all the while cursing the plane’s pilot.
A Rocky Landing
The bomber cleared the gun positions by inches and hit the ground with a tremendous thud. The incredible force of the impact made the enormous bomber begin bouncing. The bouncing disrupted its balance and one of the plane’s wings smashed into the ground. The propeller broke apart and pieces began flying through the air creating a shower of dangerous shrapnel.
The bomber began to slow down and ultimately stopped one hundred feet from the guns. Some of the engines were still operational and they kept running while the witnesses waited with bated breath. They stood there for long minutes and waited for something to happen, but no one came out of the Flying Fortress. The soldiers on the ground began muttering to each other, all wanting to know why the crew was not emerging.
No Signs of Life
The people on the ground were dumbfounded and had no idea how to proceed. The plane had just come out of nowhere with no distress call to precede its arrival. The men in charge of the guns were getting more nervous by the second. Time went by slowly. At first, five minutes, and then ten and fifteen, and no signs of life came from the plane.
There was good reason for concern, after all, this was war and underhanded tactics by both sides were far from unheard of. The bomber was just sitting there with its three remaining engines working and its propellers spinning. A British major by the name of John V. Crisp finally decided to take action after twenty minutes had gone by, but he was determined to conduct his investigation carefully.
Looking for a Way In
You could feel the tension in the air as the soldiers continued to stand around the plane with its spinning propellers. There was still nothing moving inside or any sign of the crew. Major Crisp, knowing that time was short, began to search the outside of the bomber. He wasn’t actually hoping to discover anything new but was in fact trying to figure out how to enter because he had no knowledge of aircraft.
Major Crisp, who was serving as an officer in the British Army at the time, was stationed at the base with the rest of his unit. He was not an airman, so it took him a while to figure out where the entry hatch for the plane was located. He eventually found it just below the fuselage and opened it. He entered the plane alone and was about to discover something unbelievable.
The Plane Was Empty
Major Crisp was concerned about finding seriously injured or deceased crewmen on the aircraft. What other reason could there be for no one trying to exit? He made his way through the thin fuselage to the belly of the plane which usually contained the majority of a B-17G’s ten crew members.
Crisp discovered some chocolate bars which had been nibbled on inside, and later concluded that “evidence of fairly recent occupation was everywhere.” He thoroughly looked around the cramped space of the fuselage, but there was no one to be found. He did locate twelve packed parachutes that had not been used. Which was pretty strange, considering he could not find anyone on board.
“The Phantom Fortress”
The Major remained all alone on the plane while continuing his search for clues as to the fate of the crew. He looked around the cockpit but didn’t see anything suspicious about the yoke. This means that in some inexplicable way, the plane not only somehow flew itself but also magically landed itself as well.
After several attempts, Major Crisp successfully turned off the aircraft’s engines. He also took a look at the plane’s log and observed several words scribbled inside, but so far nothing new had been uncovered regarding the location of the crew. This was the start of an investigation which would confound the allied forces and also the beginning of the rumors regarding the “The Phantom Fortress”, the nickname given to the plane by Stars and Stripes magazine.
Where Did it Come From?
News of the alarming incident quickly reached the chain of command who called for a hasty investigation, fearing for the crew’s safety. The inquiry was hampered right from the start by the fact that the B-17G, which had crash-landed, did not even have a name. Major Crisp reported the event to his commanders, who sent a team to investigate the matter.
Investigators arrived on the scene and located the aircraft’s serial number, which allowed commanders in the 8th Air Force to identify the plane as part of the 91st Bomber Group. This was a contingent of B-17G’s that operated out of East Anglia, England. Inquiries revealed that the bomber and its crew had taken off from there, but no one knew where they were now.
The Crew Was Found
After the plane and squadron were identified, the big question remained: what had happened to the crew? There was plenty of evidence of their time on board, so, where were they? The inquiry revealed that the cover to the Sperry bombsite had been removed, but that was the standard operating procedure for a bombardier on a run.
The packed parachutes remained a bigger question, especially when the entire crew was eventually found. The ten soldiers who had been on board were perfectly fine and spending their time at an airbase in Belgium. This left investigators even more confused and determined to discover exactly what happened.
Over Enemy Territory
The investigation revealed that the B-17G’s mission had been to bomb the Leuna oil refinery in Merseburg, Germany. The plant was in eastern Germany, which made it a dangerous target. The allies were bombing German targets relentlessly by this stage of the war.
The way it worked was that the British would bomb German targets during the night, while the Americans, who were set up in Italy and England, bombed them during the day, The accuracy of the strikes was a big issue, which is why the American strategists insisted on daytime missions for greater accuracy. This meant that the American bombers were much more vulnerable to attack. When Crisp was searching the plane, he discovered the log in the navigator’s station with the words “Bad Flak.”
The Plane Had Been Hit by Enemy Fire
Lt. Harold R. DeBolt, who was flying the new B-17G bomber, was an inexperienced pilot. At first, the trip to Germany was going smoothly but something went wrong as they were starting their bombing run. For unknown reasons, DeBolt’s plane wasn’t able to maintain the same altitude as the rest of the group.
At that moment, the Germans began to fire anti-aircraft weapons at the low flying aircraft. They scored two direct hits, one on the bomb bay which miraculously did not set off the bombs. “We had been hit in the bomb bay,” said Lt. DeBolt. “I’ll be darned if I know why the bombs didn’t explode.”
They Were Forced to Retreat
A direct flak hit also reportedly damaged one of the engines although all four were still functioning when the plane came in for its surprise landing. The crew quickly realized that they were flying alone in a damaged aircraft in low altitude over enemy territory.
The plane was facing another challenge in the form of the weather. Conditions were rough as it flew through towering white clouds. Like most everything else in 1944, the weather that year was terrible. Lt. DeBolt took the weather, the faulty bomb bay and the damaged engine into account and decided to cut their losses and return to base in East Anglia, England.
The Second Engine Gives Out
Despite Lt. DeBolt’s efforts to divert more power to the engines, the plane continued to steadily lose altitude. His next move was to order the crewmembers to throw out anything not bolted down but even after they got rid of all the loose equipment, the bomber continued to descend.
Although everyone was hoping that they would be able to make it back to base, they could plainly see that the situation was deteriorating by the minute. When a second engine stopped working, Lt. DeBolt knew he was out of options and was going to have to evacuate the plane. He set a course for Brussels and gave the order for the crew to prepare their parachutes and get ready to jump.
The Crew Evacuates
After the plane was hit, maintaining their altitude became impossible and pilot Harold R. DeBolt made the tough decision to turn the plane around and head back to England. When the second engine gave out and the propeller stopped spinning, DeBolt realized that the bomber had no chance of successfully crossing the English Channel.
It was at that point that he decided to set course for the headquarters of the 8th Air Force, which was located in Brussels, Belgium. The crew ditched the aircraft with DeBolt the final one to leave. He put the plane on autopilot and bailed out. Pilot and crew believed that the plane would continue to lose altitude and come crashing down.
A Self-flying Plane?
Although not a common occurrence, a plane continuing to fly on its own was not unheard of during WWII, but it was highly unlikely that a B-17G bomber with only two working engines would stay in the air. The crew watched the plane fly away, but the thick clouds made them lose sight of the aircraft. Little did they know that the plane was still flying when they reached the ground.
It is hard to believe that the bomber with only half of its engine capacity continued to fly through the air unmanned for several miles, but there is no other explanation. According to the captain’s report, he and his crew bailed out near Brussels, Belgium. Investigators were less than happy with this strange account. There were still many things that were unexplained or simply did not add up.
The Greatest Mystery
They were left with a crew that somehow evacuated without parachutes, a plane that flew miles on its own with damaged engines and a report full of discrepancies. However, all of these are nothing compared to the most incredible part of the ghost bomber’s story.
How did the plane land itself? The odds of an unmanned plane flying that far and then somehow landing are infinitesimal. Especially when you take into account the angle of the approach and the location of the landing. An allied base instead of, for example, the middle of the English Channel. There is pretty much no way that a plane can land like that without human involvement, which any pilot will happily tell you.
The Stories Didn’t Match
Another aspect of the mystery are the stories that don’t match up between the soldiers on the ground who saw the bomber’s landing and the crew’s account of what went down before they decided to turn back. The pilot and the crew stated that one of their engines was destroyed by the blast and another soon stopped working.
The soldiers on the ground, however, all reported that all four engines were intact and operational until one was damaged when the plane began bouncing during its rocky landing. Both versions were included in the official report, but their discrepancy was never resolved. Was there something missing in the crew’s account of the events?
The Soldiers Who Recovered the Aircraft Were Untrained
Another part of the story that didn’t match up and was never resolved, was the crewmember’s report that they were hit by enemy fire, which was the whole reason they were compelled to turn back. Major Crisp and other soldiers on the scene claimed that they did not observe any physical damage to the aircraft which would substantiate the claim of direct hits from the enemy.
This can fairly easily be explained, however, due to the rocky, bouncy landing of the plane which caused extensive damage. It is more than possible that Crisp and the other soldiers were not trained to know the difference between aircraft damage which occurred from enemy fire and damage caused by an unpiloted landing.
How Did They Jump Without Parachutes?
If we believe the crew’s version of events, it is extremely strange that Major Crisp found all of the parachutes on board the aircraft. Although it makes sense to abandon a plane if you believe it was too badly damaged by enemy fire to stay in the air, it is quite difficult to do so without using parachutes.
Sadly, we may never know why the parachutes were left behind because the official report offers no resolution this discrepancy. There doesn’t seem to be any way in which a crew could evacuate a plane except for parachutes. They would clearly not survive the fall. The only slightly plausible answer is that maybe Major Crisp in his inexperience regarding airplanes saw empty parachute packs that had already been used and believed they were full. Unfortunately, the report does not make this official, so the question remains.
The Flying Fortress Was One Tough Plane
It doesn’t really matter who had the right version of events or even if both sides got it wrong, the fact remains that the B-17G bomber miraculously landed itself. It was an extremely tough aircraft and could take a lot of hits and keep flying. Lt. DeBolt may have believed that he knew the plane’s limitations and what he had to do to keep everybody safe, but his plane had a different idea and wouldn’t quit until it got them home safe.
The B-17 seen above would also not quit before its crew got back home. You can see the damage to its left engine clearly. Despite that and with only a wing and a half, it successfully landed. That plane, however, still had a pilot and crew to help bring it in. Planes may have the ability to fly on autopilot, but not the ability to land.
A Happy Ending
This amazing story could have ended in many less fortunate ways, but this seems like the best-case scenario. The crew was found alive and well and the self-landing plane didn’t cause any more damage or injure people when it made its own emergency landing on the base.
Sadly, but unsurprisingly, many stories during the war didn’t have such a happy ending. This one was a real morale boost for the Allies during the height of the war and maybe it helped them feel a little like fate was on their side. That is no small thing at a time when it seems like all hope is lost. This is not the only unexplained incidence that took place during World War II. Keep reading to find out what happened to several other aircrews.
Mysterious Sightings During World War II
The sheer amount of action and devastation that took place in World War II was so enormous and horrific that it was impossible to properly investigate what happened in every incident or to every person. When the war finally ended, most of the efforts were focused on rebuilding and not explaining. More often than not, the aftermath of war is not filled with easy answers.
Although inexplicable, the story of the ghost bomber was only one of the strange incidents which took place during the war. There were a variety of other sightings, some of which were seen by large groups of people and others that haven’t been explained to this day. There were recurring stories about mysterious flying orbs, which were sighted by a number of pilots on both sides.
The Night Fighters
Many sightings of the unidentified flying aircraft in World War II were reported by night fighter aircraft. Night fighters, as made clear by the name, were planes that were specially modified to be able to have dog fights in darkness at night. They often had twin engines and were heavier than the planes used during the day. Two examples of such planes are the American P-51 Mustang and the British Supermarine Spitfire
These were pretty much the only planes in the war that were equipped with radar. This allowed them to identify bogeys using their equipment instead of having to actually see an enemy aircraft or rely on ground radar installations that were hundreds of miles away.
Lights in the Sky
In the same month the mysterious ghost bomber landing took place, an American aircrew which was operating a night fighter witnessed something they couldn’t explain. They were flying a British plane called the Bristol Beaufighter which was equipped with advanced radar and according to their equipment, everything seemed normal. The radar wasn’t showing any foreign objects within range, but they could definitely see something up ahead.
The crew was made up of three extremely experienced and highly trained soldiers: pilot Edward Schlueter, radar observer Donald J. Meiers, and intelligence officer Fred Ringwald. They described what they saw as, “eight to 10 bright orange lights off the left wing… flying through the air at high speed.”
Meiers contacted the ground control units to make sure that his radar was not malfunctioning. They confirmed that there was nothing to see on the equipment. The team was on a combat mission over Germany, so Schlueter decided not to take any chances and moved in for a closer look at the objects which they had been seeing in the sky for the past several minutes.
Suddenly, all at once, the lights went off. The crew didn’t know what to think, especially when they reappeared soon after, but further away from the plane and then disappeared for good. Meiers named the mysterious objects that night and his name would be used often in the years 1944 and 1945. He dubbed them Foo Fighters.
Where There’s Foo, There’s Fire
Meiers came up with the name because he was a big fan of the “Smokey Stover” cartoon, and “foo” was a nonsense word Smokey Stover liked to use. One of his favorite expressions was, “where there’s foo, there’s fire.” It seemed fitting because where there was a Foo Fighter, the light resembled fire. This was the first known use of the term to describe an unidentified flying object. The name also got new life when former Nirvana member Dave Grohl got inspired and used it for his band.
There have been many attempts at explaining the truth behind these mysterious sighting, but none of them have fully convinced Meier, his crew or the other men who served with them in the 415th Special Operations Squadron. That unit recorded more foo fighter sightings than any other in World War II.
They Appeared in Official Records
The 415th squadron’s official war diary describes numerous encounters with the unknown. There were reports of unidentified flying objects as far back as September 1941, but the sightings increased in volume drastically in December 1944. Many of them were documented in the official records.
An entry from the diary written on December 15th, 1944 reads: “Saw a brilliant red light at 2,000 feet going [east] at 200 MPH in the vicinity of Erstein. Due to [alternative interrogator] failure could not pick up contact but followed it by sight until it went out. Could not get close enough to identify the object before it went out.”
The Lights Followed the Planes
The log reports a similar occurrence on December 18th, but in this instance, more than one light appeared. The entry reads: “In Rastatt area sighted five or six red and green lights in a ‘T’ shape which followed [aircraft] thru turns and closed to 1000 feet.” The fact that the lights interacted with the plane and followed it, caused them to wonder if they were related to a secret German project, or were something else completely.
“Lights followed for several miles then went out. Our pilots have named these mysterious [Illegible] which they encounter over Germany at night ‘Foo-Fighters.’” After the event, one of the pilots was asked how it felt to witness the strange lights which were following his plane, he replied that he was, “scared shitless.”
The Lights Appear on Radar and Chase a Plane
An especially dangerous incident took place on December 23rd in which a Beau pilot and his crew felt actively threatened by the lights. At first, the pilot observed “two orange glows” heading towards them at a fast pace from the ground. He called it in and in this case, ground radar was able to spot the objects.
The so-called “glows” became level with the plane and began to pursue it. The pilot maneuvered the aircraft to try and evade them, making sharp left and right turns and even going into a steep dive, but he was unable to shake them. After two minutes, the mysterious lights, still totally under control, simply flew away and soon disappeared into the night.
The Lights Had Superior Capabilities
One of the most worrying facts about the foo fighters was that they seemed to be able to fly much faster than the planes the British were using. Additionally, whenever a pilot tried to get closer to them, they simply flew away and seemed to easily outrun them. Most importantly, these strange lights could execute maneuvers that were still impossible for the aircraft of the day.
An entry from the war diary of the 415th Squadron from Christmas Eve night in 1944 read, “Observed a glowing red object shooting straight up. It changed suddenly to a plan [sic] view of a [aircraft] doing a wing-over and going into a dive and disappearing.”
They Made the News
The lights were clearly intriguing; therefore, it was not surprising when the crews of the planes began to talk, and the information reached the public. Some heavily redacted reports were published in several newspapers. They mentioned the objects but did not have all the details which the aircrews had observed. For example, an incident report from a radar operator describes their speed:
“I had frequently picked up a target on the radar screen that appeared to be a conventional aircraft. But… upon being tracked [it] would accelerate to a fantastic speed, which made it impossible to set a rate on and even more difficult to identify. So, we referred to them as ‘ghosts’”
Investigations but No Definite Explanations
The incidents were investigated by the US military, but the conclusions they arrived at could still not fully explain the behavior of the objects. The pilot of a B-17 aircraft who was pursued by a Foo Fighter, which he referred to as “a small disc”, for over 250 miles talked about the incident with an intelligence officer and recounted his experience.
“It was a new German fighter, but [he] could not explain why it did not fire at us, or if it was reporting our heading, altitude, and airspeed, why we did not receive anti-aircraft fire.” Interestingly, although the mysterious lights were observed by many, they did not actually attack or damage any of the aircraft they encountered or followed.
Possible Explanation #1: St. Elmo’s Fire
One of the possible explanations for the orbs that were observed is a weather phenomenon known as St. Elmo’s fire. St. Elmo’s fire is typically bright blue or purple and occurs on pointed objects when there is a strong electric field in the atmosphere. This occurrence was first spotted on ships when the mast produced a fire-like trail during lightning storms.
The phenomenon also takes place on planes in similar conditions, creating the effect of a trail of fire on the tips of their wings. Pilots, however, rejected this explanation, pointing out that the lights were able to maneuver in impossible ways. If what they had seen was St. Elmo’s fire, that meant it came from an aircraft, but no typical plane could fly as fast or turn as quickly as the foo fighters had.
Possible Explanation #2: Ball Lightning
Another issue with the St. Elmo’s fire theory is that it generally appears like a meteor or a tracer and is not sphere shaped like what was seen by the aircrews. Although, there is another weather phenomenon called “ball lightning” which does present in spheres and looks more like what the pilots saw.
Ball lighting occurrences in history are astonishing. There are many descriptions of enormous flashes of light that lead up to an explosion, some of which even caused fatal injuries. However, although ball lightning strikes are longer than typical lightning strikes, they are still quite short, and they would never behave like the lights which were observed by the pilots. This explanation for foo fighters was also rejected.
Possible Explanation #3: Silver Balls
So, the pilots had considered and rejected weather phenomena as the cause of the lights. They then turned their attention to the next natural suspect, their opponents on the battlefield: the Germans. A news report from December 1944 refers to the Germans’ efforts to disrupt the Allied radar and electronic warfare systems.
The Germans would reportedly release balls into the skies which were “silver in color” and of a “metallic nature”. This was following their attempts to disrupt radar by releasing tiny foil strips into the air. The sightings were around the same time as when the Germans were using the silver balls, but none of the pilots from the 415th squadron ever believed that this is what they saw.
Possible Explanation #4: Feuerball/Kugelblitz
Everybody knows, that while World War II was taking place, the Germans concentrated enormous resources on the development of “wonder weapons”. One German Army Major described a couple of such weapons after the war. Major Rudolf Lusar maintained that the Germans had created Feuerball and Kugelblitz, tiny remote-controlled jet aircraft.
They were allegedly equipped with klystron tubes whose function was to send out an electrical current through the air which would disrupt the engines of the Allied bombers. That could explain why the orbs had trailed the planes, but the klystron tube was never actually operational. Making it likely that the Germans would equip the small aircraft with a different, working weapon.
Possible Explanation #5: Battle Fatigue
The idea of wonder weapons didn’t make sense, because the lights never even tried to attack or inflict damage on the planes and the pilots quickly dismissed them as a probable explanation. Another theory came up, which suggested that the pilots and the rest of their crew were suffering from battle fatigue, caused by the pressure of flying continuous combat missions in a stressful environment.
It is not unheard of for battle fatigue to induce hallucinations, but it seemed highly unlikely that several different crews would all describe such similar experiences and in essence, share the same hallucination. When you take into account that the lights were all seen in the same limited area, this explanation simply did not hold water with the aircrews.
Possible Explanation #6: Pilot Vertigo
Scientists and psychologists rely on hard proof and quantifiable claims and do not hold much stock in unverified date. The Navy carried out project X-148-AV-4-3 soon after the end of the war and its focus was on “pilot vertigo,” also known as spatial disorientation.
Dr. Edgar Vinacke, the lead physiologist on the project, concluded in his findings that, “Since aviators are not skilled observers of human behavior, they usually have only the vaguest understanding of their own feelings. Like other naive persons, therefore, they have simply adopted a term to cover a multitude of otherwise inexplicable events.” That convenient explanation still does not clarify why entire crews in different locations shared the same sightings.
A Sighting From the Ground
From all the possible explanations offered, the most likely seems to be that the lights were some kind of German secret weapon, but even that theory doesn’t resolve everything. Especially when you take into account that the foo fighter sightings were not limited to the European theater of operations.
In September 1941, a Polish ship was transferring British soldiers, when two men suddenly noticed a “strange globe glowing with greenish light, about half the size of the full moon as it appears to us.” They informed one of the officers and he came over and observed the phenomenon alongside them for over an hour. These men were obviously neither pilots, nor in the air, so they could not be suffering from “pilot vertigo.”
Foo Fighters in Japan
Foo fighters were not only seen by American pilots, German and Japanese pilots reportedly also observed them during their missions. This is one of the most well-known photographs which refers to foo fighters and it originally appeared in the 1975 photo history by G. De Turris & S. Fusco, titled “Obiettivo sugli UFO.”
There has been much discussion about the authenticity of this photograph, but experts agree that it would be a strange choice to go to the trouble of altering due to its poor quality. What cannot be explained, is the light in the background. It was captured by a Japanese photographer and matches the profile of other foo fighter sightings.
The CIA Investigates
In the end, there were just too many reports of the incidents seen above for the U.S. government to simply dismiss. They convened the Robertson Panel in 1953 to formally investigate reports of unidentified flying objects. Since other sightings which took place after the war had come to light, the previous explanations were not holding up and the public was eager for answers.
At first, the Robertson Panel’s mission was to investigate the occurrence of unidentified flying objects that had been reported flying over the area of Washington DC. The CIA was in charge of the investigation and they were supposed to decide if the mysterious sightings were a threat to national security.
Nothing New to Offer
The Panel’s original findings were classified because they contained sensitive information about ongoing military operations, which could not be revealed without posing a risk to national security. Since then, however, they have been declassified and the public gained access to some extremely unsurprising conclusions.
Caltech physicist Howard P. Robertson and several other top scientists who were familiar with “experimental aviation technology” came to no official conclusion but decided that most of the sightings were caused by the pilots’ misidentification of flying objects. The occurrences which did not correspond with this finding were determined as something which is similar to misidentification, but which needed further study.
Many explanations have been offered, but none of them have completely convinced the public or the aircrews who observed the phenomena with their own eyes. Does that mean that these unidentified flying objects are actually from another world? No one knows, and all the circumstantial and quantifiable data on the planet has not been able to provide the answer.
There is one more theory about foo fighters that we still haven’t discussed. Richard Ziebart, the historian for the nearby 417th squadron, heard many of the stories directly from the pilots of the 415th. After which he came to this conclusion: “I think the foo fighters didn’t show up on the radar because they were plain light. Radar had to have a solid object. If there was any bogey out there, the pilots would absolutely be able to tell.”
Pilots are the best witnesses for sightings of unidentified flying objects. To the untrained eye, a weather balloon or zeppelin may seem like something from another world, but pilots have expert knowledge of the shape and aerodynamics of aircraft and understand the physics behind their maneuvering capabilities.
Pilot sightings of UFO’s are not limited to the second World War. In 2004, an F-18 flying out of San Diego managed to capture incredible footage of a “tic-tac” shaped object flying rapidly. “It accelerated like nothing I’ve ever seen,” the pilot explained to The New York Times. “I have no idea what I saw.” Theories that the pilot glimpsed an American superweapon seem farfetched, meaning that he was essentially tricked by his own government. What we do know, is that UFO’s in various shapes and sizes are out there and since no one has been able to make contact with them (as far as we know) their sightings during WWII and more recently are still a mystery.