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RWD RWD-5 DWL RWD-5
 The RWD 5 was constructed by the RWD team of Stanisław Rogalski, Stanisław Wigura and Jerzy Drzewiecki (their designs were named RWD after their initial letters). It was a further development of earlier RWD aircraft series, especially of its direct predecessor, the RWD 4. It shared the same wing shape and construction, while the fuselage was totally new, constructed of steel frame, unlike its wooden predecessors. The fuselage had a modern shape and a closed canopy with panoramic windows.
Mixed construction (steel and wood) high-wing cantilever monoplane, conventional in layout. The fuselage of a steel cro-mo tubeframe, covered with canvas on a wooden frame (with duralumin in engine section). Trapezoid one-part wing, canvas covered (plywood in front), two-spar, with no mechanization, fastened to the fuselage framework with four clamps. Elastic trailing edge connecting rib ends extended from the fuselage to the ailerons. After the coating was tightened there were characteristic bogging. Ailerons - cantilever, differential +10 deg/-25deg. The wing was designed in accordance with technical documentation of the yet unbuilt wing to the PZL-3 bomber by engineer Władysław Zalewski. 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 stabilizers were cantlever, wooden construction, covered with plywood. Control surfaces without balancing surfaces and trimming tabs, covered with cloth. Horizontal stabilizer adjustable during flight with a handwheel placed on the left-hand side of a pilot's cabin. Fin and tailplane were ply-covered, and rudder and elevators were fabric-covered, in later models a taller fin and rudder was employed. A crew of two, sitting in tandem in a glazed cockpit, with dual controls and individual doors on the right (one in RWD-5bis). Control stick from the back seat could be removed.The baggage holder was behind the back seat.Control panel was equipped with speedometer, altimeter, compass, time clock, engine-speed indicator, oil manometer and fuel indicator.A noise muffler installed on the exhaust gas pipe, and cabin heating was with hot air taken from a heater installed on the exhaust gas pipe (it was removed on RWD-5bis). Conventional fixed landing gear, with a rear skid, wheels in teardrop covers on serial aircraft.Fixed, two wheels, with tail landing skid, three-legs, oil-air shock absorbtion. Tail landing skid half-springing, not controllable. Wheels with low-pressure tyres suspended on forked rocker arm supported on shock-absorbing angle strut and shielded with alluminium fairings. 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).Some models of RWD-5 were equipped with wheel brakes. SP-AGJ prototype had high-pressure tyres and three-legs with shock-absorber supporten on lower fuselage section. The shape of wheel fairings differed on different models. Fuel tanks of capacity 110 liters in center of wing section.
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.
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. 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. 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.
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 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. Engine in front, with tractor two-blade wooden propeller of a fixed pitch. A variety of 4-cylinder air-cooled inverted straight engines were used, most typically Cirrus Hermes IIB (105 hp (78 kW) nominal power and 115 hp (86 kW) take-off power). Used also were 130 hp Hermes IV or de Havilland Gipsy III, or 120 hp Walter Junior 4. The RWD 5bis and RWD 5 SP-LOT had a 130 hp (97 kW) de Havilland Gipsy Major. The first prototype (registration SP-AGJ) was flown on 7 August 1931 by its designer Jerzy Drzewiecki. It was built in new workshops of Warsaw University of Technology near Okęcie airport, from 1933 converted to Doświadczalne Warsztaty Lotnicze (DWL) company.
After successes of the prototype in air competitions, a small-scale series production was set up, mostly for the Polish Aero Club. Series aircraft had improved landing gear. Two were built in 1932 (registration SP-AJA and AJB), five in 1933 (including the single-seater RWD 5bis), eleven in 1934 (including one in Aero Club workshops in Lublin) and one more in 1937 (SP-BGX), for a total of 20 aircraft. In 1932, the RWD 5 was shown at the International Air Show in Paris.
The prototype, SP-AGJ, underwent various modifications; in 1933 it was re-engined with a Cirrus-Hermes IV, and later was fitted 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.
 SP-AGJ c/n 34
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.
RWD-5bis, in the place of the back seat had additional fuel tank of capacity 300 liters, the doors and windows for back seat were removed. RWD-5bis had more comfortable pilot's seat, designed for long flights, with rubber pneumatic pillows, armrests, footrests and lighting for night flights.On RWD-5bis an additional tank of capacity 300 liters was installed in place of the back seat, and two additional wing tanks, each 113 liters were installed. Oil tank of capacity 35 liters was placed just in front of the pilot's seat, under the cabin's floor.
RWD 5s were mostly used as trainers and sport planes by Polish regional aero clubs. They scored good results in local competitions, starting from 1931, when the prototype won the 3rd South-Western Poland Flight (pilot M. Pronaszko) and the 4th Touring Aircraft Contest (pilot Franciszek Żwirko). As sport and touring planes, they were later superseded by the RWD 13, and were relegated mostly for training. Three were written off before 1939.
In March 1933 a special single-seater variant was built, called RWD 5bis (registration SP-AJU), powered with 130 hp Gipsy Major engine. The rear cabin was replaced with an additional 300 l (79 US gal) fuel tank, and the windows were removed. Additional fuel tanks were added in wings, the fuel capacity reached 752 l (199 US gal) in total and a range increased to 5,000 km (3,100 mi). Stanisław Skarżyński flew this plane from Warsaw to Rio de Janeiro from 27 April to 24 June 1933, on a path of 17,885 km (11,113 mi).
 RWD 5bis SP-AJU
During his travel, on 7 May/8 May, Skarżynski flew the RWD 5bis across the southern Atlantic, from Saint-Louis, Senegal to Maceio in Brazil. The flight took 20 hours 30 minutes (17 hours above the ocean). He crossed 3,582 km (2,226 mi), establishing a distance record in the FAI light tourist plane class. The RWD 5bis was at that time the smallest plane that has ever flown across the Atlantic — its empty weight was below 450 kg (1000 lb), loaded 1100 kg (2425 lb). The plane had no radio nor safety equipment, due to weight. It returned to Europe on a ship. After its record-breaking flight, the RWD 5bis was converted to a two-seater variant without additional tanks, and used by Skarżyński.
One aircraft was used by LOT Polish Airlines in 1933–1936 for taxi flights (registration SP-LOT), one by LOPP organization (SP-LOP). After the outbreak of World War II, during the Polish September Campaign, at least one RWD 5 was utilized as liaison aircraft. Also, Maj. E. Wyrwicki flew RWD 5 from Romania to besieged Warsaw. None of the RWD 5s survived the war.
One RWD 5 was sold to Brazil in 1938 (former SP-LO, removed from the Polish registry on 4 December 1936) and registered there as PP-TDX in 1939. Its airworthiness expired in 1943.
In late 1990s, a flying replica of the RWD 5, named RWD 5R, was built in Poland by EEA991 association. It flew first on 26 August 2000, and is powered with 140 hp LOM Praha Avia M-332 engine.
Modern RWD 5 replica, 2005
RWD 5
Engine: 1 × Cirrus Hermes IIB, 115 hp (86 kW), Hermes IV, 130 hp / Gipsy III, 120 hp / Walter Junior, 120 hp
Wingspan: 10.2 m (33 ft 5 in)
Length: 7.2 m (23 ft 7 in)
Height: 2.05 m (6 ft 9 in)
Wing area: 15.50 m² (166.8 ft²)
Wing chord: 1.75 m
Wing profile: Bartel 37 IIA
Empty weight: 430 kg (950 lb)
Loaded weight: 760 kg (1,675 lb)
Useful load: 330 kg
Fuel consumption: 22 l/h
Maximum speed: 202 km/h (109 knots, 126 mph)
Cruise speed: 170 km/h
Stall speed: 75 km/h
Range: 1,080 km (583 nm, 670 mi)
Endurance: 6 hr
Service ceiling: 4,700 m (15,400 ft)
Take-off run: 110 m
Rate of climb: 4.6 m/s, 276 m/min (905 ft/min)
Wing loading: 49 kg/m² (10.0 lb/ft²)
CX min: 0.035
CZ max: 1.35
Crew: One, pilot
Capacity: One, passenger / trainee or second pilot
RWD-5bis
Engine: DH Gipsy Major, 130 hp
Wingspan: 10.2 m
Wing Area: 15.5 sq.m
Wing profile: Bartel 37 IIA
Wing Chord: 1.75 m
Length: 7.2 m
Height: 2.05 m
Max Take-Off weight: 1100 Kg
Empty weight: 447 Kg
Max Wing Load: 71 Kg/sq.m
Max Speed: 210 Km/H
Cruise Speed: 175 Km/H
Landing Speed (With Max Load): 90 Km/H
Flight Endurance: 29 hr
Theoretical Max Range: 5000 Km
Fuel Consumption: 26 Lt/Hr
Cx Min: 0.035
Cz Max: 1.35
Crew: 1 Pilot
 RWD-5
 RWD-5bis
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