In 1929 three of the Sekcja Lotnicza's most active and promising light aircraft designers, Stanislaw Rogalski, Stanislaw Wigura and Jerzy Drzewiecki, who formed the RWD team, managed to obtain the exclusive rights to the use of the Sekcja Lotnicza workshop at Warsaw-Okecie. The facility, at first known as Warsztaty Lotnicze, was used to built light aircraft and gliders. In April 1931, the D.W.L. was formed, and the RWD team formally separated from the Sekcja Lotnicza.
D.W.L. set itself the task of designing and developing light aircraft as a prime concern. Small-scale production of the selected types, in batches of 10 to 20, was envisaged to cover the cost of experimental and development work, and in the case of large orders license rights were to be offered to other Polish factories. D.W.L. successfully resisted all attempts by the Department of Aeronautics to nationalize the company and was the only privately-owned aircraft factory in existence in Poland in the late 'thirties.
In the final years before the war, D.W.L. employed on average about 300 people, and the total number of airframes completed at the D.W.L.'s Okecie establishment exceeded 300. When war came in September 1939, D.W.L. evacuated its Okecie factory, and nine of its airworthy aircraft reached Rumania on September 14. Eventually D.W.L. ceased operations, Rogalski, Wigura, Drzewiecki and many staff members went separate ways, about 25 ending up in Turkey, organizing and running the Türk Hava Kurumu-Uçak Fabrikasi (Turkish Air League-Uçak Factory).
In 1930 the RWD design team conceived a new two-seat high-wing cantilever light tourer monoplane, designated RWD 5, which represented a further evolution and refinement of earlier models. The aircraft was of composite construction and embodied a completely new fuselage with a rectangular-section structure of welded steel-tubes covered with fabric. Two fully-enclosed amply-glazed tandem cockpits, with provision for dual controls, were situated below the wing. Aft of the rear seat was a large baggage locker. Doors to both cockpits were on the starboard side of the fuselage, and cabin windows were made to hinge outwards from the bottom for ventilation.
The undivided tapered wing, a two-spar structure of wood with plywood D leading edge, was covered with fabric and bolted direct to the top of the fuselage. On the standard production aircraft the wing aspect ratio was slightly reduced, the overall span being cut from 34 ft 5.5 in (10.5 m) to 33 ft 10 in (10,3 m), and wing area increased from 161.5 sq.ft (15 sq.m) to 166.8 sq.ft (15.5 sq.m). The tail unit, with a cantilever tailplane, was constructed of wood. Fin and tailplane were ply-covered, and rudder and elevators were fabric-covered, in later models a taller fin and rudder was employed. The tailplane was adjustable in flight.
The undercarriage of the production model was of the divided type and consisted of two D.W.L. rubber-in-compression legs, running from the sides of the fuselage, with the lower ends hinged to the bottom of the fuselage by short axles and radius rods. The compression legs were enclosed in streamlined fairings, and the medium-pressure Dunlop wheels were often fitted with large spats. A semi-leaf spring tailskid was used. The wheel track was 5 ft 11 in (1.8 m).
Alternative powerplants included the 105-115 hp Cirrus-Hermes IIB, 120-130 hp Cirrus-Hermes IV, 130 hp de Havilland Gipsy-Major, or 110 hp Walter Junior four-cylinder inverted in-line air-cooled engines, driving a Szomanski two-blade wooden airscrew. Other in-line engines of similar output could be installed. Two fuel tanks, with a total capacity of 58.12 gal (220 l) were mounted side by side in the wing above the cabin. The oil tank was carried externally at the bottom of the fuselage on the port side.
Work on the machine was delayed by the move from the University's primitive workshop to the new establishment at Warsaw-Okecie. Construction of the prototype began at the new factory in September 1930, but due to extreme financial difficulties and other problems arising from the move, the aircraft was not finished until July 1931. Powered by the Cirrus-Hermes IIB the RWD 5 flew for the first time on August 7, 1931, proving eminently successful. Registered SP-AGJ (c/n 34) the aircraft was flown a week later to victory in the 3rd Tour of Southwestern Poland by Mieczyslaw Pronaszko, and less than two months after its first flight it came first in the 4th National Lightplane Contest, piloted by Franciszek Zwirko.
The first year of D.W.L.'s existence was a critical one, and, apart from the RWD 5 prototype, only one other aeroplane, the record-breaking RWD 7, was completed in 1931. Soon, however, the prospects began to improve, and in addition to a Government contract for a new Challenge tourer, the RWD 6, orders for the RWD 5 were mounting. In the spring of 1932 work on the first batch of ten RWD 5s began, and this was followed by another batch of ten in 1933.
The production model differed from the prototype in having a redesigned undercarriage with medium-pressure wheels and a more efficient windscreen and improved cabin windows. The first two production machines, the Cirrus-Hermes IIB powered SP-AJA and SP-AJB, c/ns 58 and 59, named Kolejarz I (Railwayman) and Kolejarz II, were financed by the Railwaymen's Union, and officially presented to the Warsaw Aeroclub on November 13, 1932.
The prototype, SP-AGJ, underwent various modifications; in 1933 it was re-engined with a Cirrus-Hermes IV, and later was fitted (site files) with a production-type wind screen and Dunlop medium-pressure wheels in place of the earlier Palmer wheels. Several RWD 5s were re-engined during their life, including SP-AJA, which was fitted with a Gipsy Major in 1936. In addition to the twenty RWD 5s produced by D.W.L., one monoplane of this type was completed before the end of 1933 by the Central Aeroclubs' Workshops in Lublin.
The RWD 5s played a prominent role in the development of Polish popular flying and, in addition to extensive touring and sporting activities, some of the machines, such as SP-ARP (c/n 68), owned by the Central Board of the Aeroclub of the Polish Republic, and SP-LOP (c/n 84), owned by the Central Board of Aviation League, were operated as executive aircraft. The RWD 5s achieved a number of victories in national and regional rallies and meetings, most outstanding among them being the success in the 5th National Lightplane Contest; the competition was won by Cirrus-Hermes IV powered SP-AGJ, piloted by Pronaszko, and two Cirrus-Hermes IIB powered RWD 5s qualified for the fourth and fifth places.
The RWD 5 participated also in several international events, and gained considerable fame in the Tour of Algeria and Morocco, staged in April 1933, in the course of which SP-AJB, flown by Robert Hirszbandt, with Bohdan Kwiecinski as passenger, covered a route of 7,077 mls (11,389 km) without a hitch. Flying in greatly varying climatic conditions over difficult terrain, the monoplane won the 'Foreigners' Prize' at the Casablanca Meeting. However, all these successes were overshadowed by one of the greatest epics in the annals of Polish flying, Skarzynski's Atlantic flight.
Span: 34 ft 5.5 in (10.5 m)
Length: 23 ft 7.5 in (7.2 m)
Height: 8 ft 10.5 in (2.7 m)
Wing area: 161.5 sq.ft (15.0 sq.m)
Empty weight: 981 lb (445 kg)
Loaded weight: 1,656 lb (760 kg)
Wing loading: 10.4 lb/sq.ft (50.7 kg/sq.m)
Power loading: 14.6 lb/hp (6.6 kg/hp)
Max speed: 130.4 mph (210 kmh) at sea level
Cruise speed: 114.9 mph (185 kmh)
Landing speed: 46.6 mph (75 kmh)
Climb: to 3,280 ft (1,000 m) 4 min 20 sec
Service ceiling: 16,404 ft (5,000 m)
Range: 745 mls (1,200 km)
Consulting the RWD designers, Stanislaw Skarzynski selected for his record-breaking Atlantic flight a specially converted RWD 5, which became known as the RWD 5bis. To ensure greater comfort during long flights, the pilot's seat was provided with rubber cushions, which could be inflated in case of an emergency alighting on water, and arm rests and foot supports close to the rudder bar were fitted. By comparison with the standard model, overall span of the RWD 5bis was reduced to 33 ft 6 in (10.2 m), and empty and maximum loaded weights were 993 lb (446 kg) and 2,425 lb (1,100 kg).
Tankage was increased to a total of 198.7 gal (752 l) of fuel and 9.5 gal (36 l) of oil, which gave the machine a maximum range of up to 3,107 mls (5,000 km). A 79.25 gal (300 l) tank was fitted in the fuselage in place of the second cockpit (the door and windows of which were omitted), the balance of the fuel was carried in four tanks mounted side by side in the reinforced wing. The monoplane, conforming to the FAI Category 2 requirements (single-seaters weighing less than 992 lb, 450 kg), was powered by a 130 hp de Havilland Gipsy Major engine.
The aircraft was completed at the end of March 1933, and and a week later received the civil registration SP-AJU (c/n 67). Skarzynski intended to start his flight on 7 April, but the Aviation Technical Research Institute requested additional trials before clearing the aircraft for the attempt. These included a 10 hr endurance flight over Poland, which was made on April 15 and covered 1,025 mls (1,650 km). Clearance for the Atlantic flight was given five days later, and on April 27 the diminutive silver monoplane left Warsaw to begin its spectacular journey.
SP-AJU reached St. Louis-du-Sénégal in West Africa on May 4, and, according to an official statement, was to make an attempt on the International Distance Record for Light Aircraft in Category 2 from St. Louis in the direction of Western Europe. Skarzynski's true intention of making the South Atlantic crossing with Brazil as his destination was a well-guarded secret, revealed only when the machine was already on its way to the American continent.
The RWD 5 bis took-off for the South Atlantic flight from St. Louis on May 7, 1933, at 23.00 hr, and, after remaining airborne for 20 hr 30 min, the task was successfully completed when it landed the following day at 19.30 hr at Maceió, Brazil. By so doing the aircraft raised the International Distance Record in the FAI Category 2 to 3,582 km (2,224 miles). When, immediately after landing at Maceió, Skarzynski, bareheaded and wearing a grey suit, was approached by the chief of the aerodrome's radio station and in answer to his questions said: "I am Captain Skarzynski of the Polish Air Force. My last take-off was from St. Louis-du-Sénégal", the bewildered fellow glanced at the tiny monoplane and then at the casual-looking little man in front of him and, convinced that it was a hoax, shrugged his shoulders and walked away.
The Maceió control had been warned about the attempted crossing (the RWD 5bis did not carry any radio equipment), but expected to see an impressive, large transatlantic machine, especially so as Skarzynski by-passed Natal, the nearest Brazilian airport on his route. In fact, on arrival at Maceió, he still had ample fuel reserves for several more hours flying, but decided not to extend the flight so as to avoid a risky landing in darkness on an unknown aerodrome. Only when the registration of the aeroplane had been checked against the aerodrome's records did Maceió burst into enthusiasm.
The history of flying is punctuated with great events which mark new peaks in the excellence of a machine and in the endurance of its crew, and Skarzynski's brilliant flight was just such an event in the light aircraft field, an achievement which remains unique to this day; with its empty weight of less than 992 lb (450 kg), the RWD 5bis was the lightest machine ever to cross the Atlantic, and, because of the later abolition of the Category 2 class by the FAI, its distance record was never officially beaten.
After a triumphal tour of Brazil, including several demonstration flights, Skarzynski and his famous SP-AJU left Rio de Janeiro on board the liner Avila Star on July 11, arriving at Boulogne on 27 July. Assembled at Boulogne, the aircraft was flown to Lódi, and then, on August 2, to Warsaw, covering during the entire tour 11,375 mls (18,305 km) in 104 hr 40 min flying time, giving an average speed of 108.7 mph (174.9 kmh). On return home Skarzynski received a hero's welcome and was decorated with the Order of Polonia Restituta. SP-AJU, known as Amerykanka (American), was presented to him by the Aeroclub of the Polish Republic, and was subsequently converted to a standard two-seat configuration.