Potez 506
{{short description|Potez 501 modified to set altitude records in the 1930s}}
| {{Infobox aircraft begin
| name=Potez 506 | image=Potez 506.png | caption= }}{{Infobox aircraft type | type=Altitude record holder | national origin=France | manufacturer=Henry Potez | designer= | first flight= | introduced= | retired= | status= | primary user= | more users= | produced= | number built= | program cost= | unit cost= | developed from= Potez 50 | variants with their own articles= }} |
The Potez 506 was a version of the Potez 501 French single engine observation aircraft, specially modified to capture the World absolute altitude record. In September 1933 it set a new record at {{convert|13661|m|ft|abbr=on|0}}.
Design and development
The Potez 506 was a modification of the Potez 501 observation/bomber aircraft, itself derived via the Potez 50 from the widely used Potez 25, first flown in 1926. In 1932 Cyril Uwins set a world altitude record of {{convert|13404|m|ft|abbr=on|0}} in a Vickers Vespa VII, which the Potez 506 was designed to better. Flown by Gustave Lemoine, it reached {{convert|13661|m|ft|abbr=on|0}} on 28 September 1933, an altitude limited by icing of the pilot's eyes as he sat in his open cockpit. 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 {{convert|700|hp|kW|abbr=on|order=flip}} Lorraine 12Fd Courlis replaced by a {{convert|700|hp|kW|abbr=on|order=flip}} Gnome-Rhone 14Kbrs Mistral Major radial engine. The Potez 506 had a similar 14-cylinder. two row radial engine, the Gnome-Rhone 14Kdrs Mistral Major, which had its power increased to {{convert|800|hp|kW|abbr=on|order=flip}} at sea level by an increase in compression ratio from 5.5 to 7.25 and an improved supercharger which could maintain this output to {{convert|6000|m|ft|abbr=on|0}}. It drove a three blade propeller. In addition, the upper wing span was increased by 26% to {{convert|18.6|m|ftin|abbr=on|0}} and its area by a little more. {{convert|100|kg|lb|abbr=on|0}} 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 sesquiplane with shorter, narrower chord lower wings and outward leaning interplane struts.
Lemoine later reached {{convert|47400|ft|m|abbr=on|order=flip}} in the 506. On 11 April 1934 the Italian Renato Donati raised the altitude record to {{convert|14433|m|ft|abbr=on|0}} in a much modified Caproni Ca.113 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 {{convert|14843|m|ft|abbr=on}}. The same aircraft was flown by Maryse Hilsz to set a new women's fixed-wing aircraft altitude record of {{convert|14310|m|ft|abbr=on}} on 7 July 1937 which still stood in 1948.
Specifications (for record flight)
{{Aircraft specs
|ref=Flight 19 October 1933 p.1043
|prime units?=met
|genhide=
|crew=One
|length m=9.40
|length ft=
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|length note=
|upper span m=18.60
|upper span ft=
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|height m=3.63
|height ft=
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|wing area sqm=54
|wing area sqft=
|wing area note=
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|airfoil=
|empty weight kg=1522
|empty weight note= with instruments, fuel and oil
|gross weight kg=1883
|gross weight note=at record take-off
|max takeoff weight kg=
|max takeoff weight lb=
|max takeoff weight note=
|fuel capacity={{convert|198|kg|lb|abbr=on|0}}
|more general=
|eng1 number=1
|eng1 name=Gnome-Rhone 14Kdrs Mistral Major
|eng1 type= 14-cylinder double row radial
|eng1 hp=800
|eng1 note=at sea level. A supercharger turning at 10.92×engine speed maintained this power to {{convert|6000|m|ft|abbr=on|0}}. Output geared down 3:2. Compression ratio 7.25.
|power original=
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|prop blade number=3
|prop name=Gnome-Rhone
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|ceiling m=13661
|ceiling note=record
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References
{{reflist|2|refs=
{{cite magazine |date=19 October 1933 |title= The new altitude record|magazine= Flight|volume=XXV |issue=42 |page=414 |url= http://www.flightglobal.com/pdfarchive/view/1933/1933%20-%200797.html }}
{{cite magazine |date=26 April 1934 |title= Higher still|magazine= Flight|volume=XXVI |issue=1332 |page=844 |url= http://www.flightglobal.com/pdfarchive/view/1934/1934%20-%200414.html }}
{{cite journal |date=29 August 1948|title=Women's Records (Class C)|journal= Flight|volume=LIII |issue=2040 |pages=114 |url= https://www.flightglobal.com/pdfarchive/view/1948/1948%20-%200134.html }}
}}
Bibliography
- {{cite journal |last1=Détré|first1=Georges|title=J'ai piloté le Potez 506 à 15.000 m.|journal=Le Album de Fanatique de l'Aviation |date=March 1971 |issue=20|pages=23–28|issn=0757-4169|language=fr|trans-title=I Flew the Potez 506 to 15,000 Meters}}
- {{cite journal |last1=Roux|first1=Robert|title=De 1933 à 1936, il permit de battre trois records d'altitude|journal=Le Album de Fanatique de l'Aviation |date=March 1971 |issue=20 |pages=23–25 |issn=0757-4169 |language=fr|trans-title=From 1933 to 1936, It Broke Three Altitude Records}}
{{Potez aircraft}}