For the Blohm & Voss German concern of the World War 2 (1939-1945) period, it was only natural to interest potential buyers in their new Ha 139 seaplane mail-carrying, trans-Atlantic aircraft (then built under the "Hamburger Flugzeugbau" name) by evolving into a land-based form as the "Ha 142". The Ha 139 was not a success, with just three total examples being completed, but the design held inherently good endurance over water, reaching out some 4,000 kilometers with its four-engined arrangement. Like the Ha 139 before it, the Ha 142 was also originally developed to a Deutsche Luft Hansa mail-carrying requirement.
The Ha 142 more or less retained the form of its progenitor (stepped cockpit, "gull wing" mainplanes, split vertical tail planes along a shared, high-mounted horizontal plane) but added the all-important quality of a wheeled, retractable tail-dragger undercarriage to replace the original twin floats used in water landings. The same four-engined layout, encompassing two engines to a wing, was used. The inverted gull wing mainplanes were characterized by the inboard panels having anhedral (downward angle) and the outboard panels featuring dihedral (upward angle). The crew was increased from five to six.
The series ended up totaling only four aircraft, "Ha 142 V1" through "Ha 142 V4". Deutsche Luft Hansa operated the family for only a short time before World War 2 arrived and these undertook various mail-carrying / cargo transport roles as needed. As with other projects started near the beginning of the war (September 1st, 1939), the Ha 139's development was stunted and the type forced into military service largely as-is.
The Ha 142 was inducted into the German war machine as a long-endurance maritime patroller where its range could truly be of value. For the role, the aircraft (specifically the second prototype, Ha 142 V2) was reworked to include a lengthened, glazed nose section and carried the usual mix of Luftwaffe communications set and navigational equipment. To defend the aircraft, 7.92mm MG 15 machine guns were installed, one at the nose, a single gun to a dorsal turret (power-assisted), one gun at a rear-facing ventral gunner's position, and one gun each to the rear fuselage sides to help provide full coverage from intercepting enemy warplanes. The fuselage would be reserved for carrying conventional drop bombs, either 4 x 220lb bomb or 8 x 110lb bomb sizes.
To simplify the naming convention for Blohm & Voss aircraft, the Hamburger Flugzeugbau (Ha) designator was eventually dropped in favor of the "BV" designator for all future aircraft coming from the company. With V2 already being trialed for the maritime patrol role, it was decided to rework the V1 prototype in this same fashion, offering the Luftwaffe a pair of long-range, over-water patrol platforms early in the war. The pair went on to see short-lived wartime service while V3 and V4 were relegated to basic transport roles (cargo and troop carriers) during the early campaigns involving Denmark and Norway. As soon as 1942, however, the line was surpassed by better-performing types.
As completed, the Bv 142 V2/U1 operational model held a running length of 67.1 feet with a wingspan of 96.10 feet, and a height of 14.8 feet. Empty weight reached 24,430lb against a Maximum Take-Off Weight (MTOW) of 36,510lb. Power was from 4 x BMW 132H-1 9-cylinder air-cooled, radial piston engines developing 870 horsepower at take-off and providing for a maximum speed of 235 miles-per-hour, a cruising speed near 200 mph, a range out to 2,425 miles, a service ceiling of 30,000 feet, and a rate-of-climb equaling 1,315 feet-per-minute, all improvements over the original Ha 139.