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Blohm and Voss Bv 138 Seedrache (Sea Dragon)

Reconnaissance Flying Boat Aircraft

The Blohm und Voss Bv 138 was a pivotal floatplane in service with Germany, operating as a maritime reconnaissance aircraft.
Authored By: Staff Writer | Edited: 6/23/2019
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Year: 1940
Status: Retired, Out-of-Service
Manufacturer(s): Blohm and Voss - Nazi Germany
Production: 272
Capabilities: Navy/Maritime; Reconnaissance (RECCE);
Crew: 5
Length: 65.12 ft (19.85 m)
Width: 88.39 ft (26.94 m)
Height: 19.36 ft (5.9 m)
Weight (MTOW): 38,912 lb (17,650 kg)
Power: 3 x Junkers Jumo 205D 12-cylinder diesel-fueled engines developing 1,000 horsepower each.
Speed: 177 mph (285 kph; 154 kts)
Ceiling: 16,404 feet (5,000 m; 3.11 miles)
Range: 2,672 miles (4,300 km; 2,322 nm)
Operators: Nazi Germany (retired)
The Blohm and Voss (also written as "Blohm und Voss" or "Blohm & Voss") Bv 138 was a German flying boat that saw quantitative production during World War 2. Initially conceived of as early as 1936, the aircraft would enter service by 1940 and play the most pivotal role of maritime reconnaissance and patrol for The Reich, working on occasion in conjunction with the feared and lethal U-boat submarine crews prowling Atlantic and Mediterranean waters. Flying boats held unique performance qualities unequaled by other aircraft types of their time - they could operate at farther ranges and loiter for extended periods of time while being able to take-off and land from virtually any water source. Conversely, flying boats were traditionally slow and plodding machines, become machine gun fodder for engaging enemy aircraft and depended upon escorts or their own machine gun/cannon network for point defense.

The Bv 138 was of a most unique design. The wings were high-mounted monoplanes with pontoons mounted to either side of the aircraft. A pair of engines were mounted on the main wings and extended out onto tailbooms towards twin-fins at the tail assembly. A third engine was mounted on the upper fuselage, above and behind the flight deck.

The Bv 138 was developed from three operational prototypes, thought these early systems were fitted with under-powered Junkers Jumo powerplants and circular-type tail boom assemblies. With some revision, the Bv 138A - in prototype form - was now distinct enough to warrant the all-new designation of Bv 138A-1. These systems now featured the Junkers Jumo 205D engines of 700 horsepower.

The definitive Bv 138 system became the Bv 138C-1 model of which some 227 examples were produced. These versions would feature 1,000 horsepower Junkers Jumo engines and an impressive defensive array of both cannon and machine guns of various caliber. A single 20mm cannon was usually mounted in a bow-positioned turret while still another was manned in a rear turret emplacement. A trainable, rear-firing 13mm (0.50 caliber) heavy machine gun was fitted in the middle of the upper fuselage, just behind the mid-set engine nacelle. A single trainable 7.92mm machine gun was added to the right-fuselage side as well. Accommodations amounted to five crewmembers and an internal payload capacity of 661lb was listed and could include bombs and depth charges.

The Blohm und Voss Bv 138 was unofficially called "The Flying Cog" ("die fliegende Holzschuh") thanks to its most distinct appearance.


1 x 20mm cannon in bow-mounted turret.
1 x 20mm cannon in rear turret.
1 x 13mm machine gun in rear-facing trainable gun position.
1 x 7.92mm machine gun on trainable mount in right-side hull position.

Internal bomb load (conventional drop bombs) maximized at 661 lb.

Graphical image of an aircraft medium machine gun
Graphical image of an aircrat automatic cannon
Graphical image of an aircraft conventional drop bomb munition

Variants / Models

• Bv 138A - Planned Initial Production Model Designation; distinct tail surface design.
• Bv 138A-1 - Initial Production Model fitted with Jumo 205D powerplants of 700hp each; redesigned tail surface and new hull design.
• Bv 138B-0 - Second Production Models of which only six examples were produced.
• Bv 138B-1 - Fourteen examples produced.
• Bv 138C-1 - Definitive Bv 138 Model of which some 227 examples were produced.
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