Were Helicopters Used In WWII?
The Second World War usually doesn't evoke thoughts of helicopters. For the most part, aircraft associated with the war involves fighters and bombers. Most associate the Vietnam War with the use of helicopters. But did helicopters exist during WWII? In short, yes, there were quite a few used. In today's video we ask, were helicopters used in WWII?
At Premier History we want to take you on a journey through time and grow your knowledge to see what it was actually like to be in some of the pivotal points in World History.
Make sure to leave a Like 👍 and a Comment 📜 down below or share this video with your friends.
- - -
🔴 Subscribe to the channel: bit.ly/3pLtnXf
- - -
#PremierHistory #wwii #history
- - -
Follow Premier History on socials:
🐦 Twitter: / historypremier
📸Instagram: / premierhistory
- - -
Almost in F - Tranquillity by Kevin MacLeod is licensed under a Creative Commons Attribution 4.0 licence. creativecommons.org/licenses/...
Source: incompetech.com/music/royalty-...
Artist: incompetech.com/
Пікірлер: 554
What are your thoughts on the helicopters of World War Two? Did you know that helicopters were used during the war? Welcome back! If you are new here make sure to hit subscribe to expand your knowledge on Military History and join the growing Premier History Community!
@freedompodcast4518
10 ай бұрын
I did know they being used in World War 2, but I did not know in that amount of extensive uses. I thought they were just for bringing high-ranking officers From A to B.
@_Hotaru__
10 ай бұрын
2:04 7 thousand meters or 7km. Seven thousand kilometers is roughly 4349 thousand miles!
@croskerk
10 ай бұрын
Yes
@QuizmasterLaw
10 ай бұрын
Yes, existed and were used in combat for reconnaissance. most interesting heli was the flittner kite unpowered U-Boat foldable heli.
@tasjan9190
10 ай бұрын
"Where Eagles Dare"! The Germans are amazing, they have created absolute marvels of innovative engineering! ❤️💪🇩🇪
If you look closely at that second German production helicopter it does NOT have a single rotor. It has two interleaving rotors mounted side by side and offset by 90 degrees to each other.
@JanChvojka
10 ай бұрын
Same desing is stil in use - for example Kaman K-Max en.wikipedia.org/wiki/Kaman_K-MAX
@moosifer3321
10 ай бұрын
It also DIDN`T have a ceiling of 7000 Kilometres!!! 1st Helo in Space?
@steveyountz9184
10 ай бұрын
@@moosifer3321 Might have meant 7,000 meters, which would still be pretty high from what I have read.
@PJay-wy5fx
10 ай бұрын
@steveyountz9184 right, 7,000m is highly unlikely as that would have required a pressurised cabin. Which I highly doubt this aircraft has.
@juliane__
10 ай бұрын
For certain it never reached 7.000m altitude. This can only special purpose helis of today. The two engines would have been way too heavy to make this possible. I remember 10 years ago or something there was the first fly above the Mt. Everest.
7,000 kilometres ceiling ?? That’s higher than the SR 72!! Germans were really advanced, that’s around 23,000,000 feet, respect !!
@rongendron8705
10 ай бұрын
I hope the cabin was pressurized or the pilots had oxygen!
@mytinu
10 ай бұрын
More than the Space Shuttle 🫣
@richardbradley2335
10 ай бұрын
More of a voice'o' than a typo.
@hansvonmannschaft9062
10 ай бұрын
They already foretold they could eventually be used to resupply a future Space Station, which could be, say, at a 420 kms high orbit. Being choppers and thus able to stay put, they wouldn't have too much trouble in outer space with... holdonasec there... yeah has to have been a typo 😂🤣 Or a voice'o, as the previous commenter suggested 🙂.
@bavery6957
10 ай бұрын
7000 meters, of course... 😊
2:06 "Had an altitude of 7000 kilometer". That is very impressive. 🙂
@jeromewagschal9485
10 ай бұрын
Indeed...Not only did the Germans use helicopters during WW2, they were actually able to send them into space...They were good...
@sirbum1918
10 ай бұрын
This is how they built that secret Nazi base on the moon I saw in a documentary a few years back. Think it was called Iron Sky.
@viorelpopescu4990
10 ай бұрын
Cum sa crezi asemene idiotenie cind avioanele din cel ww altitudinea de lucru era cuprinsa inte 4500 m si rare ori depaseau 5500 - 6000 m altitudine, multe care se incumetau peste 6 000 m cadeau ca bolovanii ( mai ales cele cu carburator) 😅😅😅
@qdaniele97
10 ай бұрын
@@jeromewagschal9485I think he meant meters, which is still pretty impressive
@jeromewagschal9485
10 ай бұрын
@@qdaniele97 Yes, of course 🙂 That's still pretty high for a helicopter... Especially during WW2...
An altitude of 7000 kilometers is quite something....
@jonkelly7908
10 ай бұрын
Even Von Braun would have been impressed😂
@ronvanwegen
10 ай бұрын
Legend has it that it's still up there!
@alisdairmclean8605
10 ай бұрын
Yes, the Germans were the first to go into orbit.
@geoffreycarson2311
10 ай бұрын
??????? Metres 😂NOT Kilometres !!! lol g
@swarnamohanty3121
10 ай бұрын
7000 meters.
The FL 282 was still a 2 rotor design. They where both located at the top. They where angled outward slightly and timed at a 90 degree offset to prevent the blades from colliding
@martinsaunders2942
10 ай бұрын
This…it was a syncropter, like the later Kaman Husky and Kaman K Max
@ralphlorenz4260
10 ай бұрын
@@martinsaunders2942 Right, and not a coincidence. Anton Flettner came to the USA under Operation Paperclip (not just rocket engineers!) and became the chief designer at Kaman.... I talk about the history of helicopters a little in my book on Ingenuity and Dragonfly published last year by AIAA
@manifestman132
10 ай бұрын
@@martinsaunders2942 Also other Flettner designs Kaman also had a few others.
@darryldyke1264
10 ай бұрын
Did some work for Lufthansa in a small town called Raunheim a few years ago. There's a street called Anton Flettner Strasse there. He was a very clever guy in more than just the field of helicopters.
The 1st combat rescue mission was carried out by a Sikorsky YR-4 in Burma in April 1944. This mission was a great adventure for the distance to be covered and for only being able to take one survivor at a time, there were 4 in total, I believe that deserves a video, do you agree?
@dukecraig2402
10 ай бұрын
Absolutely, but The History Guy already covered it.
@mandernachluca3774
10 ай бұрын
I think the first ever combat rescue under war conditions was actually carried out by an FA 223 Dragon. They rescued a downed BF109G pilot.
@lucianoandrade5007
10 ай бұрын
@@mandernachluca3774 I don't know about the rescue of a BF-109 pilot, what I've read is about transporting a downed fighter without a pilot. If you can provide the source of this information, I would appreciate it.
@lucianoandrade5007
10 ай бұрын
@@dukecraig2402 Thanks.
@runlarryrun77
10 ай бұрын
I DO!
I always wished they would get more representation in gaming. They're incredibly underrated for what it's worth.
@Cookiememes.
8 ай бұрын
introducing war thunder, a game where the vr people in helicopters will destroy your tank
@3:02 the Flettner FL-282 is a 'Synchrocopter' it uses 2 intermeshed counter rotating 2-bladed rotor heads, you see this on the Kaman HH-43 Husky and the Kaman K-Max. Helicopters require counter torque in order to not spin out of control. The Synchrocopter is a unique compact design that for smaller helicopters makes a lot of sense. It requires fewer parts over all meaning it can be built as a far cheaper cost than other helicopter types. Besides lower production cost, because there are fewer parts the maintenance and repair costs are greatly reduced. The Kaman K-Max is highly popular because it is so inexpensive to buy, operate, and maintain.
@galier2
10 ай бұрын
The Kaman helicopters are direct descendants of the Flettner helicopter. Anton Flettner worked for Kaman after the war and developed the K-Max for Kaman
Flettner helicopters had duel rotors intermeshed. It looks like one, but it is two. By using counter rotating rotors, it could be flown without a tail rotor and all the power could be used for lift.
Best video I've seen on the subject yet!
My mother worked after the war for the company which had build those old German Helicopters. As kids we often climbed around the exhibition helicopters in the front of the factory while waiting for our parents to finish work. They had several of them around their factory even up to the late 1980ths until the company was finally absorbed into Airbus and the local factory got closed.
I did know they being used in World War 2, but I did not know in that amount of extensive uses. I thought they were just for bringing high-ranking officers From A to B.
The R4 was also used for Operation Ivory Soap which was classified at the time. They were aircraft repair ships that went from island to island to repair bombers and fighters as they moved across the Pacific. The helicopter ferried parts and mechanics to the airstrip
Studied each and every one of the helicopters of ww2 ! Glad you reminded me of them !
WOW! "7000 kilo meters"! You get an astronaut badge for that.
Great video!! Learn something new every day!!!
The RAF had some Sikorsky R-4's from late 1944. They were used by 529 Squadron for radar calibration. Previously they used Avro Rota autogyros.
the 282 is a twin rota , 2 two blade rotas crossing each outher
What a great video, had no idea!!
Great video
Awsome footage :)
damn germany really had outer space helis in WW2 @ 2:06 "7000 kilometers" should be "7000 meters"
Very good video. I learned several new pointers about when helicopters started. The Germans were greatly ahead with their rotorcraft innovations, especially on the U-Boats. I mainly knew about Korean War helicopter development. Again..very good job..thank you. History reader..just visited Imperial War Museum in London. I highly recommend to visit. From Washinton State, USA.
@PremierHistory
10 ай бұрын
Thanks for the support Paul, glad you enjoyed the video
You learn something everyday.I'd seen photos of similar WW2 things and assumed that they were autogyros rather than helicopters.I always thought that exotic fare like helicopters and hovercraft were children of the 1950's.
Technically the Flettner is a Syncrote (intermeshing rotor helicopter). Great video always nice to see early helicopters.
I had no idea about the U-Boat rotor kite! That’s so cool. Fun fact: there is an ultra-light aircraft design today called the gyro plane which operates in a very similar way to the rotor kite. The main difference today being the aircraft is moved through the air by a propeller instead of a U-Boat!
@TheOriginalCoda
10 ай бұрын
There's one of those German gyro-kite/gyro-gliders in a museum near me. Fascinated me as a kid.
Very interesting video thank you.
The first helicopter crossing of the English Channel was made by a captured German helicopter being flown to an English base.
Great documentary.. i know helicopter but not the history.. i hope this channel grow. Keep it up!..
Flettner worked for the American Company Karman after WWII. The Karman helicopter still use to this day the double rotor system that Flettner introduced during war.
Great job thank you 👍
Kid: Mom, when do helicopters exist? Mom: it's a long story, a long story that cannot be tell the whole script
Interesting to see the smaller copters being thrown around the sky like stunt machines. The only thing not done was inverted!
The Flettner Kolibri is one of my favorite crafts, we need more synchrocoptors in this generation.
Dad (still alive) claims to have seen one of submarine based autogiros while an officer in the Merchant Marine in WW2. Before the war his professor at NYU did vibration analysis on Sikorsky's prototype helicopter prototype. The professor hired my dad to go take measurements on the prototype, so dad knew about helicopters before WW2
@kenrobba5831
10 ай бұрын
That is interesting to me. After working on helios in the Army ( mid sixties) I got to real dislike the beasts. Fast forward; years later I was working avionics - big boon in technology that made “radio” aids and communication real practical and “affordable.” By chance meet a couple mad scientist that used VIBRATIONS to rig, adjust and trim rotors and drivelines. It made maintenance a predictable endeavor instead of a hit and proposition. They knew Mr. Sikorsky and found him to be cantankerous (funny historical note).
@saltyroe3179
10 ай бұрын
@@kenrobba5831 Sikorsky was a genius, but, he had a hard time figuring out how to make vibration manageable. That is why Sikorsky hired my dad's professor. Sikorsky paid $10 an hour to the professor and the professor paid my dad 10 cents an hour to take measurements on the prototype. While dad was sitting in the prototype, a gust of wind caused the rotors to spin and the prototype to to take off. When the tie down chain's slack was gone the prototype came down hard. My dad thus claims to be one of the earliest people to fly in a helicopter:-)
@doubleT84
10 ай бұрын
If he could clearly see the helicopter, the submarine could have spotted his ship at the same distance without the use of the kite. So why would the submarine go through setting up the kite, which would stop it from quickly diving?
@viorelpopescu4990
10 ай бұрын
@@saltyroe3179 cred maidegraba era pus pe glume
@viorelpopescu4990
10 ай бұрын
@@doubleT84 se pare ca nu intelegi multe Inaltimea zmeului putea fi contolata si astfel se putea calcula cu usurinta distanta dintre nava observata si submarin si la fel se putea calcula timpul de scufundare si disparitie s-au a ramine mut in adincuri ptru o vreme Greu pune min a pe carte lasa bazagoniile
The U-Boat copter was completely powerless and basically a suicide plane. If the spotter marked a destroyer or any other U-Boat Hunter, they unlocked him, made an alarm dive and let him drown.
Look into German test pilot Hannah Reitsch. She was the first person to fly a helicopter indoors. This took place in Berlin before the war. She was also a test pilot for the Me163 Komet. Amazing woman, to say the least. Great video my friend!! Subscribed. 👍🏽
@clausbremen
10 ай бұрын
The name is „Reitsch“, Hanna Reitsch - with a „t“ in the middle.
@jerryjeromehawkins1712
10 ай бұрын
@clausbremen Ah, thank you, Claus. I must admit, a bit of time has gone past since I learned about her. Off to edit now... 🍻
@warpartyattheoutpost4987
10 ай бұрын
@@jerryjeromehawkins1712, that bird flew a lot of birds.
@c3aloha
10 ай бұрын
Unfortunately an unrepentant Nazi too though to her dying day. In Untergang she wanted to join him in the bunker and flew the last airplane out of Berlin.
@BagoPorkRinds
10 ай бұрын
It wasn't a helicopter that she flew indoors, it was a autogyro aka a gyrocopter.
First time I've seen, let alone even heard of helicopter use in WWII. Thumbs up!
In your Intro , you forgot to mention the Rolling Stones playing while the Hueys are flying over the jungle . I always hear " Painted Black " when i think about that
@jenniferkelly6931
10 ай бұрын
All that reminds me of the film "Apocalypse now", with the Stones singing "Satisfaction" ...
Hi, Technically the Flettner had two rotors, the were intermeshing and contra rotating to eliminate the torque effect. Sikorski used the tail rotor to achieve the same effect.
Very interesting.
i knew they used them ... well done video thanks
MURICA: HELI-copter! GERMANY: HEIL-copter! ...and that's why the war started, kids.
2:04 "Altitude of 7000km" it's a monster :D
Great video, but I miss a reference to Juan de la Cierva's work on gyroplanes.
That was a hell of a Typo, an extra zero there puts it in range of dance flight. But these prototypes were well built and opened the way for today's great helicopters.
Veery veery good.🙏
Excellent video, I knew about German chopera.
7000 kilometers ? that is almost geosynchronous orbit...
The Avro Rota, an autogyro, was used to calibrate costal radar system on the british coast. Another little interesting plane.
Neither the USSR, nor the UK or Japan had any helicopters in WW2. They all experimented with autogyros though. Autogyros were big before WW2, and if not for the early death of Juan de la Cierva, the inventor of the autogyro, the helicopter might be just a curiosity today.
2:08 7000 km ?????
Thank you
I had no idea choppers were used in WW2! That’s why I put the question into you tube search engine. So glad I did! I’ve been to Flying Legends Air Shows in England but never seen or heard mention of helicopters!
2:08 damn 7000km? The Germans left the planet with an early helicopter
My dad was in the 20th Army Air force and he hatted them called them old whirley birds. I think they had a few to transport officers around and medical duties. When they used them in Vietnam he just cursed and called them useless.
Wow...amazing
As noted by another viewer, the FL282 had 2 counter rotating rotors.
I found out about the American WW2 helicopters in 1972 because a friend had a collection of WW2 aviation magazines.
2:05 Altitude of 7000 kilometers would put it about 17 times higher than International Space Station. Helicopter rotors loose some efficiency up there so this is truly a remarkable aeronautical (or is it cosmonautical) achievement.
Altitude of 7,000km??? (22,965,879 Feet) Hahahahaha
@michaeltagg492
10 ай бұрын
Obviously narrator knew nothing about helicopters, even taking into account mixing up KM''s with mt's there is hardly any modern helicopter's can operate over 7000 mt's never mind a underpowered piston engined one. He also made the mistake of saying the 208 had one rotor when it had 2 contra rotating.
@hernerweisenberg7052
10 ай бұрын
@@michaeltagg492 there are actually a few with a service ceiling of 7000m, being pushed hard some of them can land on mount everests 8848m summit.
02:07 -- "...7,000 kilometers, or 23,000 feet." -- 7,000 kilometers = 2.29 million feet
3:06 The Flettner Fl 282 was NOT a single rotor helicopter. Instead, it had two different rotors mounted on separate shafts mounted at a slight angle to one another. This allowed the two rotors to "intermesh" with one another as they rotated in different directions. The torque generated by each rotor cancelled out the other, and made the more typical tail rotor unneccessary. Flettner later became the chief designer of the Kaman aerospace company, which manufactured intermeshing helicopters later including the HH-43 helicopter used by the U.S. Air Force in the 1950s. More recently Kaman built the K-MAX aircraft with the intermeshing rotor system, which was designed for use as an "aerial truck" for missions like logging. The U.S. Marine Corps experimented with two unmanned variants in Afghanistan to provide logistics support without the need for trucks to travel dangerous roadways.
the "fu*ker Ach gayless" caught me of guard
Very interesting. I am a retired Navy / civilian helicopter pilot, and I knew about the German designs. However, I did not know about the Sikorsky R-4 seeing use in WW-II. It happens that just last night, I met a young lady who told me that her grandfather had flown helos in that war, and later for the OSS - the forerunner of the CIA.
Hi, I'm sorry but the Flettener helicopter that is shown on the video seems to have two counter rotative rotors, not a single one. Great video!
I have read in Skorzeny's biography that German helicopters were a possible option for use in the rescue of Mussolini from Gran Sasso in 1943? However they were forced to opt for gliders, due to serviceability problems?
@jerryjeromehawkins1712
10 ай бұрын
Hi John... from what I've read a Major Mors (? Might have the spelling wrong) decided to go with gliders instead of helicopters. The technology was just too new for his liking... and the gliders could be released at a distance from Gran Sasso, keeping noise to a minimum. I've always been intrigued by this daring, brilliant and successful raid. Skorzeny was quite the soldier!!
@johnp8131
10 ай бұрын
@@jerryjeromehawkins1712 Correct spelling. Harald Mors was the main man to plan and lead the raid. Skorzeney, although there, was certainly prone to self-aggrandisement. Today, due to propaganda at the time and subsequently, due to his latter exploits, you would think it all down to Skorzeny?
3:10 the Fletner Kolibri had two intermeshing rotors - and no tail rotor. Just like the Kaman Huskie.
I knew about the German helicopter designs. I did not know that they had been used. I hadn't even heard of the 'powered kite' used by the U-Boats. I also did not know that the Sikorsky design had actually seen use in WWII. Thanks for this video. Much enjoyed.
@aussie6910
10 ай бұрын
Takom make a model of the FA 330 in 1/16 scale. Hanna Reitsch gave helicopter demo's inside the Deutschlandhalle in the late 1930's after she taught herself how to fly the thing (Fa 61).
The Flettner was not a single rotor machine. It had 2 rotors, intermeshing, like later Kaman designs. This required very careful synchronization. The FA-330 was an engineless autogyro. The aircraft shown at 6:21 is a Kellett KD-1B autogyro which, from June 1939 to June 1940, flew U.S. Mail between Camden, NJ and Philadelphia. Kellett later built a couple of experimental intermeshing helicopter designs.
7000 kilometer height ? It must be going to the moon
An example of the FL282, which I think is called the Kolibri, can be found in the Ottawa air Museum. They used to keep it in the back partly assembled. I don't know if they moved it to the front but it's a cool looking piece.
The Dragon had an altitude of 7000 KM?
@roykliffen9674
10 ай бұрын
It really was a secret prototype for the V2
I knew about the helicopters and autogyros or "kites". But I did not know that the US had helicopters in use "for real" during WW2. Always glad to learn.
At 3:07 the statement of "Unlike the previous designs, this featured a SINGLE rotor above the fuselage." Uh, no. It has two rotors right next to each other. Two. They're close by each other, but there are in fact two. They "intermesh" with each other so they don't hit each other, similar to the beaters of a common kitchen hand mixer (either electric or hand cranked ones).
1931 was the first successful Auto-Gyro, a precourser to Helicopters. 'Featured' in some early films.
One advantage of helicopters such as the Flettner and various US and Russian machines was the lack if a need for a tail rotor to compensate for rotor torque.
@shelbyseelbach9568
10 ай бұрын
Ehhhh, still have to drive a second main rotor. Not sure there's a great deal of advantage there or it would have become the standard instead of a tail rotor.
@johnhickman106
10 ай бұрын
@@shelbyseelbach9568It’s a huge advantage, but more complex to design and build. When I flew MH-53J/Ms, we lost over 1400 shaft horsepower to counter torque, verse all the power going to vertical lift, like an MH-47G. We had similar horsepower numbers, but the Chinook could hover at a higher gross weight than we could. The loss isn’t due to driving another gearbox, it’s the converting of power laterally instead of vertically.
@shelbyseelbach9568
10 ай бұрын
@@johnhickman106 My statement stands. If it was worth it, it would be the norm, which it isn't.
@johnhickman106
10 ай бұрын
@@shelbyseelbach9568 No, you said there wasn’t a great deal of advantage. It is, which is why some modern helicopters do have that design. But my retort still stands.
@shelbyseelbach9568
10 ай бұрын
@@johnhickman106 When did I say there isn't a great deal of advantage? I'll wait?
The Fa223 was a beast far far ahead of its time. Highly derated according to pilot and field reports.
Thank you I had no idea Chappers were used in WWII now can you do a story on Germans useing those experimental jey pacpacks in WWII
7000 km altitude is really high! Seems to be a part of the space program.
Interesting
i always wanted to believe helicopters were introduced in war earlier than 60's
Saw a Fletner 282 on display at the US Air & Space Museum in Washington DC many decades ago.
Glad you had the Faa330
Good video. The 330 was an autogiro, it was not a helicopter. Autogiros have an unpropelled rotor, which starts rotating giving lift when the machine is moved at sufficient speed through the air. The Japanese vehicle you showed clearly was an autogiro too.
The one Hannah Reich flew in the stadium I believe was an auto gyro
I ❤ Helicopters. Especially the tilt rotors and compound helicopters.
I've heard that the US Marines tested gyrocopters in the thirties, but I've never heard any details. I'm curious as to why they were not further developed.
@chamberlane2899
10 ай бұрын
From what I can gather it seems to be a combination of a couple of factors. The gyrocopters available at the time suffered from very low top speeds making them less than ideal as a front-line combat aircraft. Their payloads were also too small to be considered for transport roles. That left liaison, though there the increased mechanical complexity of the gyrocopter led to it being superseded by the simpler J-4 and J-5 whose simple construction made them more suitable for austere operating conditions.
02:08 Seven THOUSAND Kms. WHOAA!! o__o P.S: I know it's meant to be 7000 metres :) :)
Der "Focke Helikopter wurde von Hern HeinrichFocke entwickelt, eigentlich ein Mitinhaber der "Focke-Wulf-Flugzeugwerke". Eingesetzt wurden diese Helikopter auch für die Gebirgsjäger-Truppen, um die Geschütze und andere schwere Lasten in die Berge zu transportieren. Die Flugpionierin "Hanna Reitsch" veranstaltete auch Flugvorführungen in grossen Hallen.
Advances in aerospace engineering in both America and the Soviet Union after WW2 owed their designs thanks to the inevitable capture of these advanced flying machines and their engineers and designers. Nazi Germany vastly produced, tested and put into service warbirds, helicopters, guided air-to-surface missiles and anti-aircraft missiles that could only be dreamt of in England and the United States. They were indeed the far superior to anything the allies could produce with their immense resources. Now whether they came too late to turn the tide to win the war or not, it's another story.
3:12 Looks like the Fl-282 was a dual rotor aircraft. Single engined, but with a split transmission to allow the rotors to intermesh with opposite rotations. Kaman more fully developed the concept for the US military postwar.
The 1282 has 2 overlapping rotors, not a single rotor as stated
I would love to see a video with english/japanese/etc helicopters used durin the war!
Good question. Why isn’t this topic covered more?
The 2 rotors, side by side, aren’t used anymore. But the biggest helicopter used this configuration. The style of the 282 is the same of the K-Max. Not bad ! But clearly the R4 is the first of our modern and versatile helicopters. Well the add of the « fenestron » by the French is a good and elegant perfectionnement ;)
I cannot imagine if single rotor helicopters they build as attacks helicopter.
Actualy the Flettner design had two interlocking rotors.
The FL282 has twin intermeshing rotors, not a single rotor. Doh!