Although not very known, twins have been flying since 1915. The
first was a design, named Fokker M9 or K1
(Kampfflugzeug), by the Dutchman Anthony Fokker. He lived
at that time in Germany.
Fokker used two M7 fuselages and mounted them together to form the
M9. The M7 was a biplane. On the outsides he placed the original
wings and between both fuselages he placed a new wingsection as
upperwing. The lowerwing was a combination of a wingsection and a
short fuselage. This new fuselage had the original engines of both
M7's. One was mounted in the front and one in the back driving a
Fokker placed in each M7 fuselage a gunner in the front (where now
no longer the engine was mounted). Those gunners could now shoot
next to the propeller. At those times you couldn't shoot through
the propeller. Later Fokker designed a system that could.
The first flight was done without the gunners. The plane was very
tailheavy and hard to control. This means that the CG (center of
gravity) wasn't placed on its designed place, but more backwards.
This isn't hard to believe when you know that the gunners were
placed before the designed CG. So... flying without them shifted
the CG backwards. Another problem during the first flight was that
the fuselages rotated in relation to each other. The structure
wasn't stiff enough to keep the fuselages nicely lined up.
Another flight was made with mechanics sitting in the
gunnersplace. Flight behavior still wasn't good and the whole
project was cancelled and the testplane scrapped.
Twins aren't always a failure.
In World War II the Germans made a huge glider, the Messerschmidt
Me 321 (see Giants). It was so large and heavy that 3 twin-engine
Bf 110 fighters had to be used together to tow the glider in the
air. These triple tows or "Troika-Schlepps" were very dangerous to
all planes involved.
Generaloberst Ernst Udet, who did support several weird designs
during WW II, came with the idea of making a twin, the He
111 Z (Zwilling), out of two Heinkel He 111's. This way he
hoped to create a heavy transport that had the necessary power to
tow the Me 321. Early in 1941 work began on two prototypes. They
used He 111 h_6 fuselages and created a new wing section between
the two inner engines. In this section they placed a fifth engines.
Controls were divided between the fuselages. I quote one of my
resources ("The Warplanes of the Third Reich" by William Green;
Publisher: Doubleday and Co.): "Two completed undercarriages
retained and the pilot was situated in the portside fuselage with
five throttles, full instrumentation, controls for the port
undercarriage members and the radiator flaps for the portside pair
of engines. The second pilot, situated in the starboard fuselage,
was provided with dual flying controls but no throttles and
operated the starboard undercarriage members and the radiator flaps
of the center engine and starboard pair of engines. A mechanic,
radio-operator ang gunner were accommodated in the port fuselage
and a mechanic and gunner in the starboard fuselage, the second
pilot acting as navigator." I surely hope that the pilot with the
throttles never got shot. Flying this twin from the other fuselage
without using the throttles must be hard... let's even say
impossible to land safe (personal finding).
Sometimes the five engines were not enough to tow the heavy loaded
Me 321 and they needed to use a 502 kg (1 100 lb) thrust rocket
beneath each fuselage and two 1507 kg (3 307 lb) thrust rocket
beneath the centerwing, one on each side of the central
Towing the Me 321 was done with a cable which was attached to a
cable which was fixed to both inner wing-fuselage intersections.
But each fuselage could have its own cable when smaller gliders
were towed. There were succesful trials where 3 Gotha Go 242 were
towed by a single He 111 Z.
The He 111 Z was operational since the summer of 1942, but all the
planned operations were cancelled due to not obtained strategic
goals like necessary captured airstrips. Their first operation was
to deliver Me 321's filled with supplies to the troops in
Stalingrad. Bad weather and in-between landings on overcrowded
airfields delayed the flights and when they reached Makeyevka it
was too late.
I would have liked to see the faces of the pilots, who were
standing on these overcrowded airfields, when they saw these
huuuuuge gliders coming in for landing. I bet most made a quick
prayer to protect their parked airplane.
The first real operational use of the He 111 Z - Me 321
combination was getting casualties out of the Kuban bridgehead. He
111 Z's took off with 30 casualties aboard while towing a Me 321,
which carried more than 100 casualties.
Many other operations were planned, but all were
cancelled...again. This was not due to the airplanes, but due to
the bad situation the Germans were near the end of the war.
Of the 12 delivered H 111 Z 4 remained at the end of the war. The
rest was shot down or damaged during Allied bombing.
Heinkel He 111 Z
||115 ft 6 in
||54 ft 8 in
||32 ft 10 in
||62 500 l
|Max. speed at 4880 m (16 000 ft)
5 x Junkers Jumo 211 F 12-cylinder liquid-cooled engines, each
rated at 1300 hp (1768 kW) at 3810 m (12 500 ft)
Fuel capacity 4270 liter 940
Another German twin was the Messerschmidt Me 609. It was formed by
two Me 309-fighters. The Me 309 was intended as a replacement for
the Me 109, which had no longer a superior performance in relation
to the Allied fighters like the Supermarine Spitfire. It also
lacked the necessary range. But the Me 309 development did progress
Only nine Me 309's were planned. The tests with the first Me 309
showed several teething problems such as overheating engines,
wobbling and snaking groundhandling, high control forces. At the
time when the 3th Me 309 was made, the Me 262 was already in
production. The Germans saw no future in the further development of
the "obsolete" piston-engine fighter.
But somehow there was a proposal of making a Me 609 out of Me
Why they made this proposal, what advantage it would have had ...
I don't know. Could this Me 609 be related with the F-82 Twin
Mustang (a Allied proposal which did start at the end of WW II)?
Can anyone give me more details?
I would like to thank a person with callname "NiteWolf" for giving
me the data on the Me 309.
On 03-06-2001 I got a remark from Erik Bakker: " I read your page
on twin aircraft, but I missed a section on the Messerschmitt Bf
109Z version. I noticed your questions of where the origin was for
building the Bf 309Z. Perhaps this info is the 'missing link'. *
Somewhere during 1941 work began on a experimental heavy fighter/
bomber version of the Bf 109 F. Two airframes were connected to a
parallel chord center wing section to form a Bf 109Z. It was
equipped with two 1.350 hp DB 601E-1 engines and had a span of 43ft
61/3in (13.27 m). The sole prototype was damaged before first
flight in an allied attack. Perhaps this project got a second
chance with the development of the Bf 309. Further (and much more
detailed) info on the Bf 109Z can be found at http://world.std.com/~Ted7/bf1092.pdf. Some
info in these article point in opposite directions but I'll not be
the judge to that.
* 'Combat Aircraft of world war Two' written by Elke C. Weal, John
A Weal and Richard F. Barker. with Editorial Consultant J. M. Bruce
and written in co-operation with the RAF Museum in Hendon."
P51+P51=F82. Maths by a mad teacher? No no, just a description of
another twin. During WW II the Mustang or P51 was known for its
longer range. It could escort bombers to Berlin. But these flights
were very long and a fighterpilot couldn't count on a co-pilot to
prevent fatique. A tired pilot could make wrong and lethal
decisions when encountering a enemy.
Now, what to do if the range of the bombers becomes even longer?
This question became active when Consolidated Vultee B-24's
(English version got callname "Liberator") and Boeing B-29
"Superfortresses" entered service in the Far East.
Range bombers European and Far East theather
B 17 Normal at 352 km/h (220 mph) at 7625 m (25
000 ft) 1760 km 1 100
B 24 Normal at 379 km/h (237 mph) at 7625 m (25
000 ft) 2462 km 1 540
B 29 Longest range 6560 km
4 100 miles
North American Aviation did propose a simple solution. A
twin-version of the Mustang. Why not? It could be constructed in
limited time because the P-52 tools could be used. Some changes had
to be made. The original wings had to be reinforced, a new
tailplane and a new undercarriage was made. The port cockpit had
all flight and engine controls, while the other cockpit only had
enough controls to land the plane in a emergency or to let the
co-pilot fly while the pilot takes a rest (or nap).
The F-82 came too late to play a role in WW II. Only 20 of the
proposed serie of 500 F-82's were completed before VJ-Day (day of
Japanese surrender). Even thought all production of non-jet powered
aircraft stopped, some types were important enough to be used in
the post-war plans of the USAF. The F-82 was one of them.
When the North Korean Army crossed the 38th Parallel into South
Korea, the Korean War began. The only fighter to be able to depart
from the American bases in Japan and have sufficient range to make
sorties over Korea was the Twin Mustang. It was a F-82 who shot
down the first enemy airplane, a Yak 11, a trainer who tried to get
a shot at another F-82.
The F-82 could carry a pod under the midsection. This pod could
house a additional six guns (never used in operations) or a radar.
The black painted F-82G with its huge central radar pod was the
most known version of the F-82.
Its operational career ended in 1953.
The reason for the very long pod can be found in the interference
of the props. To keep the radar free of this interference it had to
placed before the props. A very long pod was the solution.
If there is one airplane that could deserve the name Chameleon it
would be the Piper Cub. The Cub has been changed in its history to
many new needs. I have no idea what need did lead to the next
variant of the Cub.
If you say to yourself: "Hey, those props are too close to each
other!", well, I did too. But if you look at the picture closely
you will see that there is more shadow to the left of the right
prop. I think that the right prop is placed a bit further forward
than the other. This way they can turn without tearing each other
Can somebody tell me why they did make this twin. Were they in
need of a larger cargospace? Did they want a 4-seater? Did they
want 2 pilots in the front? You tell me.
This site, http://www.fiddlersgreen.net/models/aircraft/Piper-TwinCub.html
, has good extra info about the Piper TwinCub.
Another twin I found was the Fouga C.M. 88-R "Gemeaux" (Twin).
It is a twin version of the Fouga C.M. 8 Cyclope. It uses its
fuselages, its typical V-shaped tails and the outer wings. They
made a new wing section between both fuselages and made a
connection under the tails (it is just visible on the frontal
picture). This twin was a testbed for the light Turboméca jet
I was searching info about a very simple glider, the LAK-16, when
I ran into this picture. I was amazed. A recent development of a
twin! The origin is the known Blanik-glider. All I had was a
picture, no data. Christophe Meunier (better known as the writer X.
toff for his books about twin-boom aviation) was so helpful to give
me his data. I called this one the "twin-Blanik".
Christophe Meunier gave me: "Name : SSAKTB SL-2P (SSAKTB =
Specialus Sportives Aviacijos Konstravimo Technologinis Buras =
Special bureau of sport aviation design and technology)
Source : Jane's All the World Aircraft 1988-89 page 643
History : Soviet glider (lithuanian) for aérodynamic studies, used
to carry wing profiles under test. First flight : June 25th 1987.
Manufactured by linking 2 Czechoslovakian gliders L-13 Blanik. One
prototype has been made, probably one only (enough for the required
testing). Two-seater : tandem cockpits in the port fuselage. Span
18.8m - Length 8.4m - Weight 0.79t empty and 0.95t maximum."
I got a mail from "Rusty" (Donald Fulford,
firstname.lastname@example.org), he mentions the existence of another type
of twin. But he likes more data. Can anybody help him?: "Years ago
I saw a picture of a twin Air Coupe, in FLYING MAGAZINE. It was
built by an air show pilot. It was joined with a new center section
main wing, and one of the twin vertical tails was removed and the
horizontal tails attached. This gave it a triple tail similar to a
constellation. The left wing and fuselage was painted in one
stripped pattern and the other wing and fuselage were painted in a
contrasting stripped pattern. This made the twin look like two
aircraft in very close formation. The aircraft was used for
aerobatics. I am thinking of building a 1/4 scale R/C version. I
wonder if I could find two real air coupes, cheap enough to build a
replica? If you already know about this aircraft and have pictures
could you email copies to me?"
I got mail from Christophe Meunier (Better known as X. Toff, a
writer). He listed for me A LOT of twins. Man, I didn't know there
were that many twins around!
X. Toff wrote some books about twins. He mentioned me on the 4th
August 2003 that he finished a new book about twins. Go see
http://cmeunier.chez.tiscali.fr/index.htm. Sure is good stuff. The
English version of his Asymmetric-twins page can be found at
« As reference data, here is an adding from Christophe Meunier (X.
Toff as a writer), international expert for twin-boom aviation at
the Air Britain association of aeronautic historians : * In my
(French) book "Fantômes Fourchus" published in 1998/2000 ("Forked
Ghosts, the twin-boom projects designed between 1939 and 1945" (see
http://www.la-plume-du-temps.fr/2-12.htm) are illustrated the
twin-planes of WW2 : - Twinning projects, like the He 111Z : North
American Twin-P-51G / XP-82 Twin-Mustang, Reggiane Re 2005
Bifusoliera, Macchi C205 Bifusoliera, Fiat G-58 (G-55 Bifusoliera),
Messerschmitt Bf 109Z / Me 409 (209Z) / Me 609 (309Z) / Me 509Z / E
2-26 (209Z'), Dornier Do 335Z / Do 435Z, Junkers Ju 635 (Do 335Z'),
Heinkel He 111Z-4m/3m, Klemm/DFS Kl 25Z, Blohm und Voss P.167 (Bv
250Z), DFS 203 (230Z), General Aircraft Twin-Hotspur, Slingsby T-27
Black Widow (Twin-Cadet) ; and fake ones : Boeing/Nomura
Twin-Fortress (Twin-B-29), Blohm und Voss/Nomura Bv 426 (Bv 226Z).
- Twin-fuselage projects without twinning, like the Ar P.530 (or E
530) : Savoia-Marchetti SM-92, Lockheed Recon P-38,
Pemberton-Billing PB-43/47 Venturi, Kaiser Flying Cargo Ship,
Kaiser-Hughes HK-1 Liberty, Blohm und Voss P.123/125, Snead XLRH-1,
North American RD-1120, Caproni Ca 380 Corsaro, PWS 46, Renard R
42, Tachikawa Dai-Ni-An/Dai-San-An, Bréguet Br 850/500t/1000t,
SSSR-123, DFS 332. * In my forthcoming book "Supplement #1 to
'Forked Ghosts'" (publishing scheduled for February 2003) are
illustrated further twin-planes of WW2 : - Twinning projects, like
the He 111Z : CAPRA R90 (Double R80), Junkers Ju 290Z,
Messerschmitt Me 323Z, Winkler Doppelrumpf ; and many fake ones :
F+W D-3805 (Double D-3801), Republic/Gifford P-47 Doublebolt,
Curtiss/Nomura P-40 Twin-Tigerhawk, Hawker/Lloyd Hurri-Twin,
Caudron/Pug C714 TE, Heinkel/Tucker He 162Z Volkszwilling,
Messerschmitt/Meunier Me 163Z,
Focke-Wulf/Baker Fw 190Z, Focke-Wulf/Bagnall Ta 152Z,
Focke-Wulf/Mumford Ta 183Z,
Messerschmitt/Shestakov-Brooks-Zuijdwegt Me 262Z, Gloster/Higgs
Twin-Meteor, Douglas/Winthrop C-53 Walla-Walla (Twin-Skytrooper),
Avro/Bagnall Warrior (Twin-Lancaster), Junkers/Wearmouth Ju 52Z,
Dornier/Meunier Do 18Z, Dornier Do 417 (217Z), Heikel He 219Z,
Dornier/Fordham P.256Z, Blohm und Voss/Nomura Bv 238Z,
Consolidated/Nomura Twin-Model-36 (Twin-Peacemaker),
Mitsubishi/Miura Twin-Zero A6M3-Z/A8M1, Kawanishi/Ishiduka
Twin-Shiden. - Twin-fuselage projects without twinning, like the Ar
P.530 : Blohm und Voss P.166, British unknown asymmetric, Rosatelli
CR.50 (no picture for this one, does anybody know it ?) ; and fake
ones : Blohm und Voss/Shestakov Bv 241, Lockheed/Winthrop Kiwi,
Tupolev/Nomura Gigantskii,. - That does not include Mistels like
the Me262/262, that has been featured as a plastic model in the MPM
catalogue. * In my private twin-fuselage database, I have also
recorded : - Twinning projects, like the He 111Z : Fokker M9/K I
(Twin M8, 1915) Blackburn TB (Twin L, 1915), Voisin Type O (double
M, 1915), Khioni/Anatra 4 (Twin Anade/Anasal, 1916), Boeing
Twin-Boom 747, Lockheed Twin B007 (Twin-C-5), TsAGI Twin
(Twin-An-225), Fouga CM.88R (Double CM.8), Vickers Two-fuselage
VC-10, SSAKTB SL-2P (Twin-Blanik), Wagner Twin-Cub, Twin-Ercoupe,
Schweizer SA 2-38 Condor (Twin SA 2-37), Dassault Twin-Ouragan ;
and fake ones : Lockheed Twin-C-141, Douglas Twin-Skyhawk, BAe
Twin-Harrier, McDonnell Twin-Phantom, Convair Twin-Hustler, BAC
Twin-Lightning, Lockheed Twin-Starfighter, Hanger Twin-Guppy. -
Twin-fuselage projects without twinning, like the Ar P.530 : Wight
Twin-Seaplane (1916), Avro 721 Slip-Plane, Bestetti-Nardi BN.1,
Rutan 202-11 Boomerang, La Bourdette-Halbron HT.1, Mc
Donnell-Douglas Cryoplane, Avia LE P-3.4, Tupolev ANT-22/MK 1,
Blériot 77/350/370, Zschach R, Adlershof R, Devoize bifuselage,
Letov S 41/56, Martin Twin-Hull Ocean Plane, LAF Desmons, DTD
Twin-fuselage, Schmued-Beeman-Balfour Twin-fuselage fighter, Albert
bifuselage, Lockheed 1937, Belyayev DB-LK, Payen
Pa.445/P.360TP/361/362/370, Molniya-1000, Hamburger P.13, Custer ?,
Blohm und Voss Patent 685480, NASA Ames, CLST LP-901, Clarkson
Golden Flight, Junkers J-1000/Junkerissime, Avicraft model, Martin
1938, Komet 1953, Saalfeld Möwe, Boeing 320, Horkey
Twin-Mustang-Racer, Pennypacker & Patterson 1931, Super Stik
60, Martin Spacemaster booster, Sarpolus Twin Cut, Myassichchev
MGS-6/8, Leduc 030, WIG S-90-200 ; and fake ones : Mc Donnell S2B
Kestrel, Pulverizer, Trench Art Biplane T123, Dollarkönigs,
Winthrop Dual-fuselage triplane. - Focused on twin-boomers,
carrying a tailpane (or foreplane), I have not recorded the
twin-pod flying wings (Fauvel binacelles, Khai-3, etc), sorry...
This is all, as far as I know - you understand why I needed to
focus on 1939-45 years for writing and illustrating a book on such
Help requirement : apart of twin-planes and twin-fuselage
aircraft, I am interested in twin-boomers with a central pod, and
for this, I am desperately looking for one source : Flying review
August 1945 (a Mr Kotuba article about the ideal post-war aircraft,
called Airsedan). Does anyone have it ? Thanks a lot."»
I could add this next twin, the Twin-Ercoupe, thanks to the hard
work of Sam Berliner III. He contacted the owner of this picture,
Grady Thrasher III, and could give me his permission to use this
picture. Sadly the site of Sam Berliner III filled with weird
airplanes is down. If you know where it can be found today, please,
I was happy to see the Pipistrel Taurus 4. A modern electric
airplane. And yes ...it uses the fuselage of the Pipistrel
Taurus...twice. If you wonder why it was designed this way, just go
see the video. It tells it all.
Thanks to Taja Boscarol, public relation manager of Pipistrel, i
was able to get some pictures of the project. Info at: www.pipistrel.si
My opinion about twin:
hmmm....seeing these examples I think that twins were only used as
hasty solutions for a typical temporary problem. Assembling a twin
was done much faster than designing a completely new airplane and
making the necessary tools and rigs.
But they also had some disadvantages.
The F-82 had two single cockpits. The co-pilot couldn't help the
pilot if he got shot. He could only fly the F-82 to the nearest
base. Once there the first aid could be done... maybe too
The He 111Z had twice the internal volume of the H111. But I bet
that a new freighter with the same total volume could carry larger
parts. Just look at the Super Guppy (see "Giants"). A wider
fuselage gives the possibility to load larger parts.
Imagine if they would even have used the He 111Z as a bomber. It
would be a BIG problem if one fuselage had a release problem during
the bombing. The asymetrical load would flip the airplane on its
One thing still puzzles me. Fauvel, a French airplane manufacturer
specialised in unswepted flying wings (go see the Fauvel section in
the Nurflugel site), did propose some military airplanes. I found
some pictures of them in the book "Les Ailes Volantes" by Alain
Pelletier (ISBN 2-7268-8444-X). It mostly are twins. But he didn't
use existing fuselages. Every project had a new fuselage (actually
two of the same design). Why????? Did he attempt to reduce the side
area to prevent being hit by fighters? I have no clue. Can anyone
help me clear this one out?
Another similar project was the Arado P530 (go see www.luft46.com)
. It enhances two newly designed fuselages. But this project got
cancelled because it had no advantages when compared to the H 111
Z. It even had disadvantages, due to the fact that the H 111 Z had
very few new parts, most were stock H 111 parts. I guess that this
would have killed all the Fauvel asymmetrical proposals before they
left the drawingboard.
A few related sites:
The site of Christophe Meunier:
A page about the French "Gemeaux" (In French):