| Potez 40 | |
|---|---|
 | |
| Role | Colonial policing andtransport aircraft Type of aircraft |
| National origin | France |
| Manufacturer | Societe des Avions Henri Potez |
| First flight | Late February - March 1931 |
| Number built | 1 |
ThePotez 40 was a French three-engine, bracedhigh-wingmonoplane designed and built in response to a French government programme for colonial transport and policing aircraft duties.[1]
The Potez 40 was an all-metal aircraft covered withduralumin, longitudinally corrugated at approximately 100 mm (4 in) pitch throughout.[2] The wing was rectangular in plan apart from its rounded tips and was built around two I-sectionspars. On each side a parallel pair ofairfoil sectionstruts braced the wing from the forward and rear spars to the lowerfuselagelongeron.[1]
The fuselage was in three demountable parts.[3] The nose region forward of the pilot was smooth and slightly rounded but merged into a corrugated, flat sided and rectangular cross-section fuselage. The centralSalmson 9Ab 172 kW (230 hp) nine cylinderradial engine was mounted on the extreme nose, completely uncowled and driving a two bladedpropeller. The pilot's compartment had a shallow, framed and angled pair of plane windscreens just ahead of the wingleading edge with an internal door to the main cabin, which was lit by long, shallow side windows and accessed by a large triangular door defined by the lattice fuselage structure.[1] Just behind the wingtrailing edge there was an open dorsal gunner's position, which at some point in the Type 40's development housed a pair ofmachine guns on a standard rotatable mounting[1][4] The detachable rear section carried theempennage, which was constructed in a similar way to the wings. In early drawings thefin was triangular and the rudderunbalanced[1] though this was modified by the time the Potez 40 was displayed, unflown, at the 1930 Paris Salon into a taller vertical tail with a clearly extended tip.[4] The horizontal tail was mounted near the base of the fin and was semi-elliptical, with straight leading edges and recessedelevators. It was braced from below with a pair of struts on both sides[1]
The two outer Salmson engines were mounted, uncowled, on the forward wing bracing struts, with extended streamlined bodies behind them which connected to the rear bracing strut; the forward struts were reinforced by jury struts to the wing roots and the rear bracing struts by vertical jury struts to the rear spar.[1][4] The Potez 40 had atailwheel undercarriage with its main legs with rubbershock absorbers mounted vertically below the outer engine extensions; the mainwheels were hinged on widely spaced V-Struts from the lower fuselage[1] and were sometimes enclosed underspats.[4]
The Potez 40 made it first flight atMéaulte around the end of February 1931[5] and after satisfactory initial trials[6] was flown to the military test centre atVillacoublay at the end of May 1931.[7] After a long period of modification, it returned to Villacoublay for competitive tests in late 1932.[8] In the interval it was tested with two other makes of engines and proposed as a commercial transport.[9] It was Potez's last three-engine design. By 1935, the development of the Potez 40 had been abandoned, and the airframe was offered for sale.[10]
Data from Les Ailes (2 April 1931)[1]
General characteristics
Performance
