Staff Writer (Updated: 4/4/2016):
Design of the Ju 88 fell to W.H. Evers and Alfred Gassner and was developed along the lines of a bomber flying fast enough to evade enemy interceptors and ground-based fire. Junkers engineers had interested the German Air Ministry with their Ju 85 prototype, a conventional twin-engine form with a twin vertical tail fin arrangement. From this was evolved a new Ministry requirement of August 1935 which called for a three-crew fast bomber capable of up to 2,200lb payloads and a prototype contract was handed to Junkers for the work in June of 1936. Five prototypes - V1 to V5 - then followed, differing mainly in proposed armament fittings and V6 then followed with a revised undercarriage design. A formal first flight ensued on December 21st, 1936 and this was prototype V1 with civilian markings to hide the aircraft's true military bombing role from the world.
Development continued and the design evolved into a heavier form with reinforced wings, a four-man crew, and a lengthened fuselage. The aircraft now proved stronger for the rigors of dive bombing and the extra crewmember aided in general operation of the aircraft and its defense. The type proved an operational range of 620 miles and could reach speeds of 320 miles per hour while under the stresses of a 4,400lb war load. While Luftwaffe authorities pursued the design with a certain level of vigor - even as its pursued competing designs from Dornier and Heinkel - developmental issues delayed finalization of the product which was initially intended for service during 1938. The type was formally adopted in 1939 and on call in limited numbers during the German invasion of Poland to begin World War 2 (September 1st).
The Ju 88 sported a rather ungainly appearance but was consistent with the German bomber design trend of the period. The heavily-framed cockpit was held in a stepped arrangement overlooking a short, glazed nose section. The fuselage was expectedly tubular and terminated in a single rounded vertical tail fin at rear. The wing mainplanes were low-mounted along the forward section of the aircraft with the engine nacelles installed at each wing leading edge. The engines sported large spinners and drove three-bladed propeller units. Most Ju 88 versions held a belly gondola for a defensive machine gun position. The undercarriage arrangement was of the typical tail-dragger configuration featuring two main legs.
Primary bomber models were designated collectively as "Ju 88A" and came with 2 x Junkers Jumo 211 series engines while including six subvariants. Ju 88A-0 marked pre-production aircraft which led to the A-1 model and its Junkers Jumo 211B-1 series engines of 1,200 horsepower output each. A-2 models followed with Jumo 211G-1 engines while A-3 served as dual control trainer platforms. Ju 88A-4 was an improved A-model form and introduced rounded wingtips at the ends of extended wing mainplanes. A-5 models were earlier A-model marks no brought up to the A-4 model standard complete with its changes.
A-4 models featured a crew of four made up of the pilot, a bombardier who doubled as the nose gunner, a radio operator also serving as the rear gunner, and a navigator doubling as the ventral gunner. Dimensions included a length of 15.3 meters with a wingspan of 20 meters and a height of 5 meters. Maximum Take-Off Weight (MTOW) neared 30,870lb while power was served through 2 x Junkers Jumo 211J series liquid-cooled inverted V12 engines of 1,400 horsepower each unit. Maximum speed reached 317 miles per hour with a range out to 1,430 miles, a service ceiling of 29,500 feet, and a rate-of-climb in the 770 feet-per-minute range. Armament was centered on six 7.92mm MG81 machine guns - one at the nose, another at the cockpit windscreen, two set at the rear of the cockpit flightdeck, and the pair fitted to the ventral gondola facing rear. Bomb load capacity reached 3,100lb through in the internal bomb bay though up to 6,600lb could be fielded along external hardpoints at the expense of drag and increased weight.