Construction of three Ju 252 prototypes began in July 1940, the design being a result of various studies to provide a Ju 52/3m follow-on for Deutsche Lufthansa. When it emerged, the Ju 252 V1 bore little resemblance to its illustrious forebear other than the trimotor layout. The Trapoklappe hydraulic rear loading ramp was an important feature, enabling the carriage of light vehicles and the dropping of para-retarded loads in flight. Power came from a three 1,340 hp (1000 kW) Junkers Jumo 211F liquid-cooled engines in annular cowlings and had accommodation for 21 passengers in a pressurised cabin.

The Ju 252 V1 (D-ADCC) first flew in October 1941, followed by the V2 and V3 in the winter months. Despite an order from DLH for 25 aircraft, the needs of the Luftwaffe were by now far greater than the airline, and Junkers was ordered to develop the aircraft for military needs. Consequently the first production prototype, the Ju 252 V4 (DF+BP), featured defensive armament of one 13 mm (0.51 in) MG 131 machine-gun in a EDL 131 dorsal turret and two 7.92 m (0.31 in) MG 15 machine-guns in the beam position. Maximum speed was 272 mph (438 km/h) with a maximum cruising speed of 242 mph (390 km/h). The service ceiling was 20,670 ft (6300 m). Range of 2,473 miles (3980 km) with maximum payload. With only 4,410 lbs (2000 kg) of payload range increased to 4,100 miles (6600 km). Empty the aircraft weighed 28,880 lbs (13100 kg), with a normal loadout it weighed 49,560 lbs (22480 kg) and with maximum overload it weighed 52,910 lbs (24000 kg). It had a span of 111 ft 10 in (34.09 m); length 82 ft 4 in (25.10 m); height 18 ft 10 1/4 in (5.75 m) and a wing area of 1,320 sq ft (122.3 sq m).

The Ju 252 V4 underwent acceptance trials at Rechlin, before being used for special transport tasks, these including the delivery of DB 606 engines to KG 40 at Bordeaux-Mérignac for its He 177s. Junkers proposed that the Ju 252 should replace the Ju 52/3m with transport units, but the transport situation was so desperate that it was felt imprudent to upset the production lines. Furthermore, the Ju 252 would place a greater strain on the supply of strategic materials.

Major assemblies for 11 further aircraft had been completed when work on the Ju 252 was called to a halt, although Junkers was allowed to complete them. Assigned prototype numbers V5 to V15, they were officially designated Ju 252A-l and were delivered during the latter part of 1942. The Trapoklappe installation, good range and high internal capacity made them naturals for covert missions. One was delivered to the viermotorigen Transportstaffel (later Lufttransportstaffel 290) to fly alongside the Ju 290, while others joined the Gruppe Gartenfeldt, which used them for special missions such as agent drops in North Africa on behalf of the Reichssicherheitshauptamt. By the time this unit was redesignated I./KG 200 in February 1944, two Ju 252s were still on charge.  

Specifications (Junkers Ju 252A-1)

Type: General Purpose Transport

Crew: Three or Four depending on loadout

Design: Junkers Flugzeug un Motorenwerke AG Design Team

Manufacturer: Junkers Flugzeug un Motorenwerke AG

Powerplant: Three 1,340 hp (1000 kW) Junkers Jumo 211F inverted Vee 12-cylinder engines.

Performance: Maximum speed 272 mph (438 km/h); maximum cruising speed 242 mph (390 km/h); service ceiling 20,670 ft (6300 m).

Range: Range of 2,473 miles (3980 km) with maximum payload. With only 4,410 lbs (2000 kg) of payload range increased to 4,100 miles (6600 km).

Weight: Empty 28,880 lbs (13100 kg) with an absolute maximum take-off weight of 52,910 lbs (24000 kg). Normal loadout it weighed 49,560 lbs (22480 kg).

Dimensions: Span 111 ft 10 in (34.09 m); length 82 ft 4 in (25.10 m); height 18 ft 10 1/4 in (5.75 m); wing area 1,320 sq ft (122.3 sq m).

Armament: One 13 mm (0.51 in) MG 131 machine-gun in a EDL 131 dorsal turret and two 7.92 m (0.31 in) MG 15 machine-guns in the beam positions.

Variants: Ju 252 V1-V15 (later all were designated Ju 252A-1) .

Avionics: None.

History: First flight (Ju 252 V1) October 1941.

Operators: Germany (Luftwaffe).

The transport glider DFS 331 was designed by engineer Hans Jacobs from DFS and built by the Gothaer Waggonfabrik. It was intended to be a larger and more useful version of the DFS 230 with the capacity to carry a cargo load of 2,500 kg (5,512 lbs). The glider had a length of 15.81 m (51 ft 10.5 in), a span of 23 m (75 ft 6.5 in) and an empty weight of 2,270 kg (5,005 lbs). Maximum speed on tow was 270 km/h (168 mph). Operated by one pilot who sat in a cockpit placed high on the left of the fuselage, the DFS 331 was fitted with a large loading door on the side, and skids for take-off and landing. Only one example was built, in 1941. There was a projected twin variant, the DFS 332, composed of two DFS 331 gliders joined together, with a middle wing section and tailplane.

The tremendous success of the pre-war Ju 52/3m airliner naturally led Junkers to look for a successor, and after several designs settled on the Ju 252. However, the Ju 252 was a metal aircraft and the raw materials were in short supply for transport aircraft, as were the Jumo 211F engines. In order to redress this, Junkers began design of a wooden version powered by three 1,000 hp (746 kW) BMW-Bramo 323R-2 radials in the spring of 1942. The resultant Ju 352 superficially resembled the Ju 252, but the wooden wing was mounted further back on the fuselage, which itself was a composite structure. It was marginally larger than the Ju 252 but easily distinguished by its squared tail fin rather than the rounded one of the Ju 252. Incorporated in the rear was the Trapoklappe, a hydraulically-powered loading ramp which allowed the rapid loading of bulky items, although vehicles were usually winched up the ramp rather than driven. A detachable tailcone could be replaced by a towing hook for gliders. Defensive armament consisted of a single 20 mm MG 151/20 cannon in a HD 151/2 power operated turret behind the cockpit. Provisions were made for two 13 mm (0.51 in) MG 131 machine-guns in the beam positions.

Dubbed the 'Herkules' by the manufacturer, the Ju 352 V1 made its first flight on 1 October 1943, from the satellite plant at Fritzlar. The V2 second prototype flew soon after, and an order for 10 pre-production Ju 352A-Os came quickly. Production Ju 352A-ls were delivered to the Luftwaffe from February 1944, but by the summer the worsening war situation led to the cancellation of transport aircraft production. A total of two prototypes, 10 Ju 352A-0s and 33 Ju 352A-ls were completed.

In service, the type showed itself a worthy successor to the Ju 52/3m, proving rugged and reliable. The wooden propellers featured reverse pitch, which was appreciated greatly by crews, considerably reducing the landing run by up to 60 percent. The aircraft were assigned to various transport units for special missions, with most going to the infamous I./KG 200 (commanded by Major Gunther Mauss). Most ended up with the Grossraum-Transportgruppe at Tutow, although only a few supply missions were flown towards the end of the war. On 25 April 1945, 23 were still on strength but most were destroyed as the Allies neared the airfield.

At least two escaped the destruction, one being captured by the British and ferried to RAF Farnborough for evaluation. The other surfaced after the war in Czechoslovakia, where it was restored and presented as a personal gift from the Czech government to Josef Stalin. Developments were planned, including the Ju 352B with 1,800 hp (1343 kW) BMW 801 radial engines, although none left the drawing board

The tremendous success of the pre-war Ju 52/3m airliner naturally led Junkers to look for a successor, and after several designs settled on the Ju 252. However, the Ju 252 was a metal aircraft and the raw materials were in short supply for transport aircraft, as were the Jumo 211F engines. In order to redress this, Junkers began design of a wooden version powered by three 1,000 hp (746 kW) BMW-Bramo 323R-2 radials in the spring of 1942. The resultant Ju 352 superficially resembled the Ju 252, but the wooden wing was mounted further back on the fuselage, which itself was a composite structure. It was marginally larger than the Ju 252 but easily distinguished by its squared tail fin rather than the rounded one of the Ju 252. Incorporated in the rear was the Trapoklappe, a hydraulically-powered loading ramp which allowed the rapid loading of bulky items, although vehicles were usually winched up the ramp rather than driven. A detachable tailcone could be replaced by a towing hook for gliders. Defensive armament consisted of a single 20 mm MG 151/20 cannon in a HD 151/2 power operated turret behind the cockpit. Provisions were made for two 13 mm (0.51 in) MG 131 machine-guns in the beam positions.

Dubbed the 'Herkules' by the manufacturer, the Ju 352 V1 made its first flight on 1 October 1943, from the satellite plant at Fritzlar. The V2 second prototype flew soon after, and an order for 10 pre-production Ju 352A-Os came quickly. Production Ju 352A-ls were delivered to the Luftwaffe from February 1944, but by the summer the worsening war situation led to the cancellation of transport aircraft production. A total of two prototypes, 10 Ju 352A-0s and 33 Ju 352A-ls were completed.

In service, the type showed itself a worthy successor to the Ju 52/3m, proving rugged and reliable. The wooden propellers featured reverse pitch, which was appreciated greatly by crews, considerably reducing the landing run by up to 60 percent. The aircraft were assigned to various transport units for special missions, with most going to the infamous I./KG 200 (commanded by Major Gunther Mauss). Most ended up with the Grossraum-Transportgruppe at Tutow, although only a few supply missions were flown towards the end of the war. On 25 April 1945, 23 were still on strength but most were destroyed as the Allies neared the airfield.

At least two escaped the destruction, one being captured by the British and ferried to RAF Farnborough for evaluation. The other surfaced after the war in Czechoslovakia, where it was restored and presented as a personal gift from the Czech government to Josef Stalin. Developments were planned, including the Ju 352B with 1,800 hp (1343 kW) BMW 801 radial engines, although none left the drawing board.

Specifications (Junkers Ju 352A-1 Herkules "Hercules")

Type: General Purpose Transport

Crew: Three or Four depending on loadout

Design: Junkers Flugzeug un Motorenwerke AG Design Team

Manufacturer: Junkers Flugzeug un Motorenwerke AG from a satellite plant at Fritzlar

Powerplant: Three BMW-Bramo 323R-2 Fafnir 9-cylinder air-cooled radial engines rated at 1,000 hp (746 kW) for take-off and 1,200 hp (895 kW) with water-methanol injection.

Performance: Maximum speed 230 mph (370 km/h); service ceiling 19,685 ft (6000 m).

Range: 1,860 miles (2995 km) with maximum payload.

Weight: Empty 28,150 lbs (12769 kg) with a maximum take-off weight of 43,200 lbs (19595 kg).

Dimensions: Span 112 ft 2 3/4 in (34.21 m); length 80 ft 8 1/2 in (24.60 m); height 18 ft 10 1/3 in (5.75 m); wing area 1,379.93 sq ft (128.19 sq m).

Armament: One 20 mm MG 151/20 cannon in a HD 151/2 power operated turret behind the cockpit with provisions for two 13 mm (0.51 in) MG 131 machine-guns in the beam positions.

Variants: Ju 352 V1, Ju 352 V2, Ju 352A-0 (10 pre-production aircraft), Ju 352A-1 (33 production aircraft).

Avionics: None.

History: First flight (Ju 352 V1) 1 October 1943.

Operators: Germany (Luftwaffe).