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Dornier Do 635 (Zwilling) / (He 635 / Ju 635)

Nazi Germany (1946)
Picture of Dornier Do 635 (Zwilling) / (He 635 / Ju 635) Long-Range Reconnaissance Aircraft Proposal

The Dornier Do 635 was a proposed long-range reconnaissance platform centered around the joining of two Do 335 heavy fighter aircraft.


Detailing the development and operational history of the Dornier Do 635 (Zwilling) / (He 635 / Ju 635) Long-Range Reconnaissance Aircraft Proposal.  Entry last updated on 6/16/2018. Authored by Staff Writer. Content ©www.MilitaryFactory.com

Several German aircraft makers of World War 2 were convinced of the merits inherent in joining two aircraft by way of a common center wing section. This was most famously attempted by Heinkel with their He 111 medium bomber to produce the He 111Z "Zwilling" ("Twin") and the idea found even more success in America with the post-war North American F-82 "Twin Mustang" which saw combat service in the Korean War. The Dornier Do 635 existed as another short-lived attempt by German engineers to create a new "super aircraft" from an existing design.

The Do 635 was proposed during 1944 and the idea was simple enough on paper - join two examples of the promising Do 335 heavy fighter with a common center wing section while retaining all other original aspects of the high-performance fighter. The Do 335 was a unique fighter design in the grand scope of World War 2 as it showcased a pair of engines seated in line across a well-streamlined, cylindrical airframe. One engine was installed at the nose in a traditional "puller" arrangement and the other was fitted in the aft section of the fuselage in a "pusher" arrangement (behind the pilot's position). This combination of power made the Do 335 the fastest German prop-driven aircraft of the war but delays in acquiring the necessary engines led to fewer than forty examples delivered before the end of the conflict in Europe in May of 1945.

In the Do 335 "Zwilling" design, designated as Do 635, the aircraft was to retain the services of all four engines in their respective locations about the airframes. Each engine outputted 1,777 horsepower for a combined output of 7,108 horsepower. A crew of two was natural as each airframe was designed to hold one under their respective framed canopies. The combined fuselages generated a wingspan of 90 feet but more or less retained the same overall length (45.4 feet) and height (16.4 feet) of the original heavy fighter. Gross weight was estimated to be 72,532 pounds and performance specs included a top speed of 447 miles per hour with an impressive range out to 4,722 miles.

The unique arrangement of the aircraft provided generous operational ranges as output power and fuel stores were shared across both airframes. This played well into the intended role of long-range reconnaissance platform and onboard would be 2 x Rb 50 series cameras fitted to the portside fuselage. In addition to this, five target marker bombs would be carried to designate targets of opportunity. Due to the hefty weight of the aircraft, it was proposed to fit it with 2 x Walter rocket units for Rocket Assisted Take-Off (RATO). Landing would be conventionally accomplished as each airframe would retain its respective tricycle undercarriage.

Beyond a wind tunnel model, nothing else came of the Do 635 initiative as it was cancelled in February of 1945 amidst the worsening war situation for Germany. It is unknown what value this large aircraft would have had considering the Germans were embroiled in what was largely a defensive-minded war by this point and fighters /interceptors / night-fighters were the call of the day.

Any available statistics for the Dornier Do 635 (Zwilling) / (He 635 / Ju 635) Long-Range Reconnaissance Aircraft Proposal are showcased in the areas immediately below. Categories include basic specifications covering country-of-origin, operational status, manufacture(s) and total quantitative production. Other qualities showcased are related to structural values (namely dimensions), installed power and standard day performance figures, installed or proposed armament and mission equipment (if any), global users (from A-to-Z) and series model variants (if any).




General Assessment (BETA)
Firepower  
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Performance  
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Survivability  
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Versatility  
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Impact  
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Rating: 44 (of 100)
The rating is an internal assessment derived from forty factors pertaining to this entry.
Relative Maximum Speed Rating
Hi: 500mph
Lo: 250mph
    This entry's maximum listed speed (447mph).

    Graph average of 375 miles-per-hour.
City-to-City Ranges
NYC
 
  LON
LON
 
  PAR
PAR
 
  BER
BER
 
  MOS
MOS
 
  TOK
TOK
 
  SYD
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  LAX
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  NYC
Graph showcases the Junkers Ju 635's operational range (on internal fuel) when compared to distances between major cities.
Aviation Era
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Pie graph section
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Pie graph section
Useful in showcasing the era cross-over of particular aircraft/aerospace designs.
Unit Production Comparison
Comm. Market HI*: 44,000 units
Military Market HI**: 36,183 units
0
0


  * Commercial Market High belongs to Cessna 172.

  ** Military Market High belongs to Ilyushin Il-2.


Altitude Visualization
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  Compare this entry against other aircraft using our Comparison Tool  
National Flag Graphic
Origin: Nazi Germany
Year: 1946
Type: Long-Range Reconnaissance Aircraft Proposal
Manufacturer(s): Dornier Flugzeugwerke / Junkers Flugzeug / Heinkel Flugzeugwerke - Nazi Germany
Production: 0
Status: Cancelled
Global Operators:
Nazi Germany (cancelled)
Historical Commitments / Honors:

Military lapel ribbon for Operation Allied Force
Military lapel ribbon for the Arab-Israeli War
Military lapel ribbon for the Battle of Britain
Military lapel ribbon for the Battle of Midway
Military lapel ribbon for the Berlin Airlift
Military lapel ribbon for the Chaco War
Military lapel ribbon for the Cold War
Military lapel ribbon for the Cuban Missile Crisis
Military lapel ribbon for the Falklands War
Military lapel ribbon for the French-Indochina War
Military lapel ribbon for the Golden Age of Flight
Military lapel ribbon for the 1991 Gulf War
Military lapel ribbon for the Indo-Pak Wars
Military lapel ribbon for the Iran-Iraq War
Military lapel ribbon for the Korean War
Military lapel ribbon for the 1982 Lebanon War
Military lapel ribbon for the Malayan Emergency
Military lapel ribbon for the attack on Pearl Harbor
Military lapel ribbon for the Six Day War
Military lapel ribbon for the Soviet-Afghan War
Military lapel ribbon for the Spanish Civil War
Military lapel ribbon for the Suez Crisis
Military lapel ribbon for the Vietnam War
Military lapel ribbon for Warsaw Pact of the Cold War-era
Military lapel ribbon for the WASP (WW2)
Military lapel ribbon for the World War 1
Military lapel ribbon for the World War 2
Military lapel ribbon for the Yom Kippur
* Ribbons not necessarily indicative of actual historical campaign ribbons. Ribbons are clickable to their respective campaigns/operations.
Measurements and Weights icon
Structural - Crew, Dimensions, and Weights:
Unless otherwise noted the presented statistics below pertain to the Junkers Ju 635 model. Common measurements, and their respective conversions, are shown when possible.

Operational
CREW


Personnel
4


Dimension
LENGTH


Feet
45.44 ft


Meters
13.85 m


Dimension
WIDTH


Feet
90.06 ft


Meters
27.45 m


Dimension
HEIGHT


Feet
16.40 ft


Meters
5 m


Weight
EMPTY


Pounds
49,604 lb


Kilograms
22,500 kg


Weight
LOADED


Pounds
72,532 lb


Kilograms
32,900 kg

Engine icon
Installed Power - Standard Day Performance:
4 x Daimler-Benz DB603E V12 inverted liquid-cooled piston engines developing 1,777 horsepower each (two arranged in "puller" and two arranged in "pusher" configuration).

Performance
SPEED


Miles-per-Hour
447 mph


Kilometers-per-Hour
720 kph


Knots
389 kts


Performance
RANGE


Miles
4,722 mi


Kilometers
7,600 km


Nautical Miles
4,104 nm


Performance
CEILING


Feet
36,089 ft


Meters
11,000 m


Miles
6.84 mi


Performance
CLIMB RATE


Feet-per-Minute
1,700 ft/min


Meters-per-Minute
518 m/min

Armament - Hardpoints (0):

None. Assumed photographic camera equipment carried for the reconnaissance role. Up to 5 x target marker bombs held in starboard side fuselage bay.
Variants: Series Model Variants
• Do 635 - Base Project Designation
• Do 635 V-1 - Assumed first prototype