Douglas DC-2B

DC-2B was the designation given to Douglas DC-2 airliners fitted with British Bristol Pegasus VI radial engines of 750 hp (560 kW) in place of the standard Wright Cyclones. It is one of the rarest civil variants of the type: reference sources describe two DC-2s sold to the Polish carrier LOT Polish Airlines with this powerplant, although LOT itself operated three DC-2B aircraft between 1935 and 1939, because the two machines bought new were later joined by a third, second-hand example. Compared with the Wright Cyclones of 710 to 875 hp fitted to the 156 standard civil DC-2s, the Pegasus VI delivered, according to Polish sources, a rated output of 493 kW (670 hp) and a take-off output of 570 kW (775 hp).

The choice of British engines for an American airliner reflects the industrial and commercial context of Poland in the 1930s: the Pegasus was an engine familiar to the Polish aircraft industry, and LOT was at the time operating a mixed fleet of German, American and domestic designs. The DC-2 joined the LOT fleet in 1935, followed by the Lockheed Model 10A Electra in 1936 and the Lockheed 14H Super Electra in 1938. During this period the airline had ten Lockheed 10As, ten Lockheed 14s, three DC-2s and one Junkers Ju 52/3mge, and its network, which in the preceding years had been extended to Berlin, Athens, Helsinki and Budapest, reached Beirut, Rome and Copenhagen by 1939, for a total of 10,250 km of routes. With its cabin for 14 passengers, a crew of two or three, blind-flying equipment, an autopilot and a duplicated set of flight instruments, the DC-2 was then the most modern airliner in the Polish fleet.

The first two aircraft, purchased in 1935, received the registrations SP-ASK and SP-ASL. In February 1937 LOT bought from the German airline Lufthansa a third DC-2 in dismantled form, which the Germans had taken apart to study its structure; once assembled in Poland it was registered SP-ASJ. This aircraft, identified in the records as a DC-2-115D, had a very short life: on 23 November 1937 it crashed in the Pirin Mountains of Bulgaria during a scheduled flight between Thessaloniki and Sofia, killing all six people on board, among them captain Tadeusz Dmoszyński. According to Polish sources, the aircraft iced up after entering a storm zone at an altitude of about 3,300 metres, and the wreckage was found on 27 November 1937 at about 2,600 metres above sea level. Some sources describe the flight as a Thessaloniki–Bucharest service, while others place it on the Thessaloniki–Sofia route.

The Second World War ended the careers of the two surviving DC-2Bs. In September 1939 LOT evacuated its fleet out of Poland. SP-ASK was interned in Riga and, after the Soviet annexation of Latvia, passed to Soviet aviation; it was destroyed in 1941 during the German attack on the Soviet Union, according to the English Wikipedia on the ground at Spilve Airport by German fighters. SP-ASL was evacuated to Romania, where it was interned along with the other Polish aircraft that had reached the country. In an attempt to recover part of the fleet, LOT's management staged a fictitious sale of the DC-2, its Lockheed 14H and 10A aircraft and a Junkers Ju 52 to the British airline Imperial Airways, allocating them British registrations; pressure from the German embassy in Bucharest prevented their return and, after a few months, the DC-2 was taken over by Romanian commercial aviation.

As for technical data, Polish sources credit the DC-2 with a wingspan of 25.9 m, a length of 18.9 m, an empty weight of 5,590 kg, a useful load of 2,660 kg and an all-up weight of 8,250 kg, with a maximum speed of 330 km/h, a cruising speed of 264 km/h, a ceiling of 7,000 m and a range of 1,770 km, although other publications give slightly different values (5,400 kg empty, 8,400 kg all-up weight, 340 km/h maximum speed, a 6,840 m ceiling and a 1,745 km range). These figures apply to the DC-2 in general; no performance table specific to the Pegasus-engined DC-2B has been located, so this entry records no variant-specific figures. Nor is it documented whether the third aircraft, the ex-Lufthansa SP-ASJ, kept the Pegasus engines of its stablemates or was re-engined when assembled in Poland.