The Potez 506 was a version of the Potez 501

French French (french: français(e), link=no) may refer to: * Something of, from, or related to France ** French language, which originated in France, and its various dialects and accents ** French people, a nation and ethnic group identified with Franc ...

single engine observation aircraft, specially modified to capture the World absolute altitude record. In September 1933 it set a new record at .

Design and development

The Potez 506 was a modification of the Potez 501 observation/bomber aircraft, itself derived via the

Potez 50 The Potez 50 or Potez 50 A2 was a French two seat military multi-rôle aircraft, first flown in 1931. It did not go into service but seven variants using five different engines were produced, one of them setting several speed with useful load re ...

from the widely used

Potez 25 Potez 25 (also written as Potez XXV) was a French twin-seat, single-engine biplane designed during the 1920s. A multi-purpose fighter-bomber, it was designed as a line aircraft and used in a variety of roles, including fighter and escort mission ...

, first flown in 1926. In 1932 Cyril Uwins set a world altitude record of in a Vickers Vespa VII, which the Potez 506 was designed to better. Flown by

Gustave Lemoine Gustav, Gustaf or Gustave may refer to: *Gustav (name), a male given name of Old Swedish origin Art, entertainment, and media * ''Primeval'' (film), a 2007 American horror film * ''Gustav'' (film series), a Hungarian series of animated short cart ...

, it reached on 28 September 1933, an altitude limited by icing of the pilot's eyes as he sat in his open

cockpit A cockpit or flight deck is the area, usually near the front of an aircraft or spacecraft, from which a Pilot in command, pilot controls the aircraft. The cockpit of an aircraft contains flight instruments on an instrument panel, and the ...

. He used oxygen but had no pressure suit. The flight, made from Villacoublay, lasted 2 hrs 5min. The record breaking airframe began as a Potez 501, which was the Potez 50 with its inline, water-cooled

Lorraine 12Fd Courlis The Lorraine 12F Courlis was a W-12 (broad arrow) aero engine introduced in France in 1929. It was not widely used. Design and development In 1926 Lorraine introduced a series of V-12 and W-12 engines with steel cylinders screwed into alumi ...

replaced by a Gnome-Rhone 14Kbrs Mistral Major

radial engine The radial engine is a reciprocating type internal combustion engine configuration in which the cylinders "radiate" outward from a central crankcase like the spokes of a wheel. It resembles a stylized star when viewed from the front, and is ca ...

. The Potez 506 had a similar 14-cylinder. two row radial engine, the Gnome-Rhone 14Kdrs Mistral Major, which had its power increased to at sea level by an increase in

compression ratio The compression ratio is the ratio between the volume of the cylinder and combustion chamber in an internal combustion engine at their maximum and minimum values. A fundamental specification for such engines, it is measured two ways: the stati ...

from 5.5 to 7.25 and an improved

supercharger In an internal combustion engine, a supercharger compresses the intake gas, forcing more air into the engine in order to produce more power for a given displacement. The current categorisation is that a supercharger is a form of forced induct ...

which could maintain this output to . It drove a three blade

propeller A propeller (colloquially often called a screw if on a ship or an airscrew if on an aircraft) is a device with a rotating hub and radiating blades that are set at a pitch to form a helical spiral which, when rotated, exerts linear thrust upon ...

. In addition, the upper wing span was increased by 26% to and its area by a little more. of empty weight savings were made. The pilot sat in the rear cockpit, rather than from his usual forward position which was covered over and used to house the barographs and batteries. Like all of the Potez 25 derived aircraft, the 506 had an all wood structure with fabric covering apart from around the engine and was a

single bay A biplane is a fixed-wing aircraft with two main wings stacked one above the other. The first powered, controlled aeroplane to fly, the Wright Flyer, used a biplane wing arrangement, as did many aircraft in the early years of aviation. While ...

sesquiplane A biplane is a fixed-wing aircraft with two main wings stacked one above the other. The first powered, controlled aeroplane to fly, the Wright Flyer, used a biplane wing arrangement, as did many aircraft in the early years of aviation. While a ...

with shorter, narrower chord lower wings and outward leaning interplane struts. Lemoine later reached in the 506. On 11 April 1934 the Italian

Renato Donati Renatus is a first name of Latin origin which means " born again" (natus = born). In Italian, Portuguese and Spanish it exists in masculine and feminine forms: Renato and Renata. In French they have been translated to René and Renée. Renata is ...

raised the altitude record to in a much modified

Caproni Ca.113 The Caproni Ca.113 was an advanced training biplane produced in Italy and Bulgaria in the early 1930s. Designed as a follow-on to the Ca.100, it was a more powerful and robust aircraft capable of aerobatics. It was a conventional design with two ...

aircraft, wearing a pressure suit. Both pilots considered further records attempts and Dorati also experimented with pressure suits. On 14 August 1936 Détré flew the 506 to . The same aircraft was flown by

Maryse Hilsz Maryse Hilsz (7 March 1903 – 30 January 1946) was a French aviator known for high altitude and endurance flights. She served with the French Resistance during World War II and died in an air crash in 1946. Life In 1933 she shared the Fédér ...

to set a new women's fixed-wing aircraft altitude record of on 7 July 1937 which still stood in 1948.

Specifications (for record flight)

References

Bibliography

* * {{Potez aircraft 050 1930s French experimental aircraft Sesquiplanes