The Discreet UFO Importance Of Operation Mainbrace

Marcus Lowth
Published Date
May 30, 2021
Last Updated
October 20, 2021
Estimated Reading Time
11 min read
Posted in
UFOs, Sightings

Perhaps one of the most important events in UFO history are those that are said to have occurred during Operation Mainbrace, a NATO training exercise involving multiple countries in September 1952.

The operation featured eight NATO countries (the United States, the United Kingdom, Canada, Denmark, Norway, France, the Netherlands, and Belgium), as well as the New Zealand military. In all 80,000 soldiers were involved, utilizing over 200 planes and around 1,000 ships, and took place somewhere off the coast of Denmark and Norway.

Picture of a UFO

Were UFOs watching the events of Operation Mainbrace?

As well the general training for their own respective militaries, the operation was a discreet but purposeful demonstration of the powers of NATO amid the nuclear fears of the Cold War should such nations as the Soviet Union contemplate such an attack.

The operation also saw several UFO sightings – one of which produced an intriguing picture – that were witnessed by multiple people. In fact, the sightings were so persistent during the operation that their presence can only be seen as purposeful in overlooking the activity in the North Atlantic. However, as we will see when we examine one of the ships involved in the operation, and more specifically, what might have been on board, the reasons for such a UFO presence might be even more alarming.

UFO Activity Starts Almost Straight Away!

Most records state that Operation Mainbrace began on the 14th of September 1952 and ran until the 25th. However, according to Richard Hall, operations began on 13th September, and Hall himself writes that “sources differ on the exact dates but agree on details”. And he tells of an intriguing encounter that was witnessed by several crew [1] on board the Danish destroyer, Willemoes on that evening.

According to Hall on the evening in question, the Danish vessel was “participating in the maneuvers” in the water near Bornholm Island. However, during these, along with several other members of the crew, Lieutenant Commander Schmidt Jensen noticed a triangular-shaped object that appeared to glow a bluish color and “moved at high speed”. Jenson would later estimate that the object was traveling around 900 miles per hour (once again, some sources differ, stating the speed was as fast as 1,500 miles per hour).

Still from the television series Project Bluebook examining the Maibrace encounters

Still from the television series Project Bluebook examining the Maibrace encounters

On the same day, another sighting of fast-moving objects was reported. This time, three objects were witnessed traveling in a triangular formation. According to the details of the report, [2] the craft each gave a “white light exhaust”.

Rather than being a one-off incident, these would prove to be just the first of several sightings of strange objects during the military maneuvers. That these craft – whatever they might have been – should show up during such an operation should perhaps alert us to the fact that the intelligence behind them seemingly has a definite interest in the goings-on of the world’s militaries.

The USS Franklin D. Roosevelt Sighting

Without a doubt, one of the most intriguing sightings occurred on the afternoon of 20th September when multiple crew onboard the USS Franklin D. Roosevelt witnessed a silvery, sphere-shaped object in the skies overhead. What’s more, it would remain visible for a considerable amount of time.

At first, those who witnessed the object thought it was a weather balloon. However, when it became clear that there had been no balloon launches that day, the crew realized they were watching something out of the ordinary.

A photographer on board the ship, Wallace Litwin, managed to take several shots of the strange objects. You can see one of those pictures below which, incidentally, would only be made public decades later.

Picture by Wallace Litwin

Picture by Wallace Litwin – is the round shape a UFO?

The project chief, Captain Ed Ruppelt would state in his report [3] that the object was “plenty large enough to show up on a photo”, which he would later describe as “excellent”, elaborating how the photographer had managed to capture the “superstructure of the carrier in each one and, judging from the size of the object” it was clear that “it was moving rapidly”.

Ruppelt would continue that “although it resembled a balloon in some ways it was far from being identical” to the many balloons he and the crew had witnessed during their careers.

It is perhaps worth examining a letter [4] Litwin would write to researcher Ole Henningsen. In it, he would state that he, along with several other journalists, had managed to find out the USS Roosevelt was “carrying an atom bomb, in a small room far below the decks”. He would further state that this was denied by the Navy themselves, but after plying “some of the navy people with charm, money, and booze”, they had their suspicions confirmed and wondered whether it “might relate to the white sphere”.

This is certainly an interesting question. After all, we know that UFOs – or their occupants – appear to have an interest in such powerful weaponry and what humans might do with it. Might this atom bomb – if the report is accurate – have been what attracted apparent extraterrestrial interest.

Captain Ruppelt would also state that it was only because of the many other incidents that would occur during the operation that they pushed so hard for answers. One of those incidents occurred around 24 hours earlier, this time over the North Sea.

The RAF Topcliffe Incident

The previous day on 19th September, another bizarre and intriguing incident had unfolded. At around 11 am on the morning in question, a British Meteor jet was returning to RAF Topcliffe in Yorkshire, England.

As they began their approach to land, however, Lieutenant John Kilburn, and several other personnel, witnessed a strange “silvery” object that appeared to “sway…like a pendulum”.

Author and researcher, Nick Redfern would write of the incident in his book A Covert Agenda: The British Governments UFO Top Secrets Exposed and would include a report prepared by Kilburn. [5] In it, the lieutenant would state that the object was at an estimated altitude of around 10,000 to 20,000 feet (by comparison to the jet’s altitude of around 5,000 feet) and was “silver in color and circular in shape”. It also appeared to be traveling slower than the Meteor jet.

A plane stationed at RAF Topcliffe in the 1950s

A plane stationed at RAF Topcliffe in the 1950s

Then things turned stranger.

The jet broke off its approach and circled back around. As soon as it did so, the object stopped its motion and instead, hovered and “rotated on its own axis”. It did this for several moments before suddenly “accelerating at tremendous speed” disappearing into the distance. Kilburn would estimate that the entire episode lasted no longer than 15 to 20 seconds. He would conclude his report by stating that:

The movements of the object were not identifiable with anything I have seen in the air and the rate of acceleration was unbelievable!

Redfern would reveal that several members of the public had also reported sighting the strange object. In fact, Redfern writes that the “Air Ministry was sufficiently concerned by the Topcliffe incident to forward a one-page report to the Commander-in-Chief Air/East Atlantic”, a subdivision of NATO. Documentation was also forwarded to several other government departments.

Other Strange Sightings

Sightings would continue following the Topcliffe and USS Roosevelt incidents. For example, at around 7:30 pm – on the same day as the USS Roosevelt incident – three Danish Air Force officers witnessed a metallic, silver disc fly over Karup Field in Denmark, disappearing into the clouds.

The following day, on 21st September, six British pilots witnessed a “shiny sphere” approaching them as they flew over the North Sea. The jets would actively pursue the object, but it was much too fast for them. When they returned to base, though, one of the pilots spotted the object again and turned his aircraft to approach it once more. When he did so, it simply vanished at breakneck speed.

A week later on the evening of 27th going into the 28th of September, a surge of UFO sightings were reported in Denmark and Sweden, as well as in western Germany. Many of these reports were of a bright object with a “comet-like tail”. What’s more, these strange objects often remained visible for a considerable amount of time. One report even spoke of a large, cigar-shaped object that had several smaller objects moving around it.

However, we might be well served to examine some of the UFO sightings that took place around the world at the same time as Operation Mainbrace was unfolding. After all, if we accept that these futuristic craft can traverse vast distances in an extremely short amount of time, then we should accept that sightings separated by distance may still share connections.

Sightings Right Across North America During The Operation

Perhaps one of the first sightings to highlight occurred on the evening of 14th September in El Paso in Texas, and was investigated under Project Blue Book. On the night in question, at around 11:30 pm, three local residents would report seeing six glowing spherical objects that appeared to be traveling in a Y-formation. They would claim the objects were moving an approximate distance of 4,000 miles per hour and were at an altitude of around 10 to 12 miles.

Several hours later between 11:30 pm and 1:20 am on the morning of the 15th September in Ciudad Jaurez in Mexico, a consulting engineer, R. Portis, along with three other people witnessed six separate groups of glowing spherical objects (some stated they could be discs), each group numbering between 12 and 15 objects, and flying in a Y-formation.

A depiction of a UFO

There were many UFO sightings during Operation Mainbrace

A little over 24 hours later, at just after 6 am on 16th September over Portland, Oregon, the crew of a US Navy P2V Neptune plane witnessed five glowing objects in a circular formation. They also noticed the object on their radar. The object was visible for approximately 20 minutes. Half a day later, at 7:30 pm, three United States Air Force servicemen, along with two local residents, witnessed several white, glowing objects moving through the skies over Warner-Robbins Air Force Base in Georgia. They remained visible for around 15 minutes.

On 23rd September at Gander Lake in Newfoundland in Canada, several Pepperrell AFC operators, along with seven campers, witnessed a brightly lit craft traveling overhead, so bright, that it lit up the waters below.

The following day, at around 3:15 pm, in Aurora, Colorado, Sergeant Hughes of the United States Air Force witnessed around six, white, circular objects in the skies overhead, remaining in sight for around five minutes. Only 15 minutes later, on the other side of the United States over Charleston, West Virginia, the crew of a USAF B-29 bomber plane witnessed a stream of bright lights pass their craft. They would estimate each was around three feet in length.

Although the date is unknown, an incident over Kirtland Air Force Base in Albuquerque, New Mexico unfolded at some time in September, when radar detected an unknown object moving at approximately 700 miles per hour before suddenly slowing to around 100 miles per hour. Jets were scrambled from the base, with one source stating they fired on the object. It is not known what happened following this.

Connections To Similar Sightings Before And After?

Whether or not there are connections to the UFO presence over Operation Mainbrace, there are several similar sightings that took place immediately before the mission and immediately after.

For example, just before 11 am on the morning of the 29th of August, two US Navy pilots in a P4Y-2 patrol plane reported seeing three white, glowing objects, either disc-shaped or spherical, hovering for several moments in the air before moving away from them at blistering speed.

Only the previous evening, a disc-shaped craft circled an airliner over Le Roy, New York. Only hours earlier, at around 9:30 pm at Chickasaw and Brookley Air Force Base in Mobile, Alabama, several stationery and moving red objects were witnessed by three local residents, who would report the incident to an officer at the base. An Air Force Office of Special Investigations officer was soon at the scene and also witnessed the strange objects overhead.

Other sightings are on record in the weeks following the completion of Operation Mainbrace. In early October, over Trenton, New Jersey, the crew of an Eastern Airlines Martin 404 witnessed an oval-shaped object that glowed a blue color before changing to yellow. It passed their plane before climbing into the sky and disappearing at speed. A similar object was observed only a few hours later over Marseille in France, and again around 90 minutes later over the Franche-Comte region of the country.

A depiction of two UFOs in a cloudy sky

Might there be connections to sightings further afield?

Given the number of descriptions of white, or bright oval, or disc-shaped objects during the Mainbrace period, it might also be worth our time examining an alleged UFO crash in the Lagen River in Norway. The incident in question occurred around 7 am one morning in early October and comes to us from the research files of Ole Jonny Braenne.

According to the account, a workman – Johannes Nordlien – was waiting for his co-workers near the river when he suddenly heard a piercing howling sound, similar to that of a jet. As he looked upward, he saw a “white as snow”, disc-shaped object go screeching overhead at great speed. He followed it, watching as it hit the water of the river with a “violent splash”.

The man’s co-workers would arrive shortly after and they made their way to the river. They would claim that the water was still boiling although the craft had seemingly slipped beneath the surface. Might this white disc-shaped craft have been one of those that had been seemingly tracking Operation Mainbrace in the previous weeks?

Was There A Cover-Up In Place?

If we turn our attention back to the weeks of the operation itself, the previously mentioned Nick Redfern also writes of the testimony of a former RAF serviceman, William Maguire, who was serving out of RAF Sandwich in Kent at the time of Operation Mainbrace.

Maguire would recall how “everything was a complete flap”. He would elaborate how everything in such military operations was usually “ordered, regular, and set out”. However, in this instance, it was clear that things were “plainly out of control” and that there were “mechanics flying all over the place”.

He would ultimately reveal that a huge UFO was being tracked moving along the English Channel. And as this tracking was taking place, something akin to blind panic was almost taking over. He would recall that higher-ranking officers were blaming the mechanics for not “calibrating the instruments properly” or for not “interpreting the readings correctly”. He would further recall how the object was approximately the size of a warship and appeared to be hovering at an extremely high altitude.

View from the ship looking out to sea

Was there a cover-up of events during Operation Mainbrace?

Was there a cover-up regarding the events of Operation Mainbrace? According to Redfern’s research, it would appear it is certainly a possibility when he writes, “It would appear there are many more papers concerning the Mainbrace sightings which the (UK) government has deemed unreleasable”.

He would point to a newspaper report from December 1952 (in the Sunday Dispatch) that stated that the six pilots of the encounter over the North Sea had each been extensively interviewed by members of RAF intelligence. However, despite the “30-year rule” (that means all such records should be made public), no records of these interviews have ever been released.

The Intriguing Claims Of Chet Grusinky

There are also some intriguing claims made by Chet Grusinsky, who served on the USS Roosevelt. He would state that he had witnessed a glowing cigar-shaped object while onboard the vessel. He would claim the object had a row of windows and that he could see “figures” inside. What’s more, he could tell that these figures were “not human beings”.

He would continue that after remaining alongside the craft for several moments, it suddenly took off with alarming speed. He was so close to it that he could “feel the heat on my skin”.

He would further claim that there appeared to be an intense extraterrestrial interest in the USS Roosevelt, even pointing out that when it was stationed at its homeport in Mayport, Florida, UFO activity in the area appeared to increase dramatically.

He would also point to the rumors that atomic weapons were on board the ship. And while he doesn’t state that this is the conclusive reason for why UFO activity appears to follow the vessel around, he does state it is an interesting detail given what we know of UFOs and their occupants’ interest in the nuclear capabilities of humanity.

Perhaps, then, it wasn’t so much the military operations taking place in the North Atlantic Ocean that these alleged extraterrestrial crafts were interested in, but perhaps more exclusively the USS Roosevelt.

Just How Important Were The UFO Sightings Of Operation Mainbrace?

So, why were the UFO incidents that occurred during Operation Mainbrace so important? Although the US government had already proceeded with such studies and investigations of UFOs as Project Blue Book, the UK government, at least officially, had refused to even recognize them.

According to the research of Nick Redfern, the sightings that unfolded during Operation Mainbrace changed the UK government’s stance on the issue, if only behind closed doors. We have mentioned above that the UK military and government were aware and concerned about the UFO sightings during the 1952 NATO proceedings. So concerned it appeared they kept a much closer eye on them in the years and decades that would follow.

And why did these strange aerial vehicles – or more specifically, the occupants of them – have such an interest in the activities taking place in the North Atlantic Ocean during that two-week period in September 1952? Might there have been, as some researchers have asserted, a nuclear bomb on board the USS Roosevelt? Might other ships have been carrying equally deadly loads? And if so, why?

As more and more information on the UFO and alien question enters the public arena, the sightings that took place during Operation Mainbrace will undoubtedly make more sense. Until that time, the events will continue to fascinate and frustrate researchers for the foreseeable future.

The video below looks at UFO sightings during Operation Mainbrace a little more closely.


1 Operation Mainbrace Sightings, In the vicinity of Denmark & Norway, September, 1952, Richard Hall, NICAP
2 UFOs & NATO: The Mainbrace Affair, Nick Redfern, Mysterious Universe, April 22nd 2014
3 The Mainbrace Sightings, Ed Ruppelt, NICAP
4 Wallace Litwin Letter, NICAP Documents
5 A Covert Agenda: The British Government’s UFO Top Secrets Exposed, Nick Redfern, ISBN 9781931 044707

Marcus Lowth

Marcus Lowth is a writer with a love for UFOs, aliens, and the Ancient Astronaut Theory, to the paranormal, general conspiracies, and unsolved mysteries. He has been writing and researching with over 20 years of experience.

Marcus has been Editor-in-Chief for several years due to his excellent knowledge in these fields. Marcus also regularly appears as an expert on radio talk shows including Troubled Minds and Unexplained Radio discussing these topics.

Read Marcus' full bio.

You can contact Marcus via email.

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  • Rob says:

    Great stuff have had incounters with ets faries elementals ect

  • Julio Mariano Barriere says:

    I’ll be going to the next contact in the desert ufo conference this June 24-28, 2021 at Indian Wells, Mohave desert, Southern California. I have convince for years some of those veteran celebrities of the history channel of ancient aliens of witnessing my full permanent disclosure. I had travel throughout the United States and Canada to many ufo conferences. Those ancient alien celebrities talked about me saying that I traveled the world and hovering ufos appear. I will be showing those presentators with their ufo conference guest my hovering ufos and triangular motherships those clear or partially clear nights skies at Indian Wells, Mohave desert that last weekend in June 2021. Anyone and everyone can see this full permanent disclosure which follows me around the world with their naked eyes in full view. I’ll give you celebrities of ancient alien names who has witness my full permanent disclosure for many years. admiral Richard Byrd told congress after he went to war up against reptillian nazi ufos in Antarctica that had attack admiral Richard Byrd battlefleet at that South Pole. Antarctica needed to be thermonuclear at those reptillian nazi ufos. Russia’s president Vladimir Putin gave orders to his Russian technicians to fire Russian nuclear warhead missile at a cavern within a hollow earth in the North Pole. Their were extraterrestrials at that cavern in that North Pole. Those extraterrestrials knew that Russian nuclear warhead was aim at them so they blew up that Russian nuclear warhead at the surface of that North Pole. Scandinavians were running around their country trying to find nuclear pills of august of 2019. The Cold War started with admiral Richard Byrd suggesting orders to U.S. congress after that war broke out in 1946-1947 in Antarctica with admiral Richard Byrd U.S. battlefleet up against reptillian ***** ufos that came out of that Antarctica ocean. Their were Russian spys on that U.S. battlefleet that took videos of that Antarctica ocean war. Admiral Richard Byrd had flown over that Arctic circle around the same time that Charles Lindbergh had flown from St. Louis to New York then to London, England then to Paris, France. Admiral Richard Byrd said he saw a wide opening at that North Pole and saw ufos there. Admiral Richard Byrd had flown over the South Pole and saw a wide opening there as well and saw ufos there. Admiral Richard Byrd said that ufos fly from pole to pole within a hollow earth within minutes from north to south or from south to north. This Cold War has been going on between human world’s militaries up against malevolent extraterrestrials with their ufos at the North Pole and also at the South Pole for three quarters of a century. Theirs too much exposure about the ruling class of extraterrestrials that are shapeshifting extraterrestrials which are known as reptillians. The reptillian shapeshifters where they meet at bohemian grove near San Francisco, California. All of our world leaders and extremely rich go there the last two weeks of July. They have pedoplies running around those redwood grove trees naked. They murdered those children and drink their blood. They don’t drink adult blood because of too much toxins in the blood. They sacrifice a baby at the altar of forty foot owl name molach which that ceremony been going on since ancient Babylonian times in the Middle East. So humans serve their blood to these blood sucking vampire shapeshifting vampires. Hillary Clinton snd german chancellor Angela Merkel have cannibalism symptoms with shaking. Headhunters in Borneo or whatever Indian Ocean island headhunters have shaking of their bodies after eating humans. So humans could possibly be cattle and also human blood is drank by those shapeshifting reptillian lizards. Princess Diana Spencer had witness the Queen of England, Queen Elizabeth and her royal family all had shapeshifted into reptillian lizards. They all told Princess Diana Spencer if you reveal this HUGE SECRET to the world we will have you murdered. Multibillionaire Mohammed Al-Fared told the world that prince Phillip Rothschild had his son Dodi Al-Fared murdered as well as Princess Diana Spencer murdered as well. A M-15 secret service agent on his deathbed told the world that he had murdered Princess Diana Spencer. Princess Stephanie told the world that her mother Princess Grace Kelly was murdered by the illuminati. Princess Grave Kelly wanted to reveal the illuminati that had hidden much wealth in Monte Carlo, Monoco from the world. Donald Trump wanted space force. I spoke to a military personnel and he told me that theirs extraterrestrials that cannot breathe oxygen. He said they created fires around the world. Three billion animals had died in fires in Australia. They were many fires throughout many South American countries. Their were fires in California, Oregon, Washington state and the western provinces of Canada. I put two and two together that Donald Donald Trump wanted the U.S. marines to go to Mars. End of that story which didn’t explain why spending many billions of American tax payers money to create a sixth military branch of American arm forces and not mention any reason why!!!??? So my putting two and two together that Donald Trump wanted to wage war up against those extraterrestrials that cannot breathe oxygen and those type of extraterrestrials would want to destroyed earth’s foliage so no one can breathe. Like out of a Indepedence day movie or war of the worlds. I’m just making a little conversation here as a ufo hunter.

  • Daniel E Martin says:

    I believe we have been visited for decades. I believe there are many alien civilizations in outer space. I believe we now have the capability to go to distant planets through back enginering of crashed UFO’s. I would give anything to be able to go to another planet!

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