Flight, June 1924

THE THIRD INTERNATIONAL AERO SHOW AT PRAGUE
THE FRENCH EXHIBITS

HENRY POTEZ.

   THIS firm, although but comparatively recently established - having succeeded the "S.E.A." Company of the War period - has produced quite a number of successful machines of various types. They are exhibiting at Prague a reconnaissance machine, type XV.A.2, fitted with a 370 h.p. Lorraine-Dietrich engine. In general design, this machine is of the orthodox fuselage tractor biplane type. Upper and lower planes are of equal span, the top plane being in three sections - two outer ones attached to a smaller centre section. The lower plane is in two sections, each attached direct to the lower longerons of the fuselage. Upper and lower planes are separated by four pairs of duralumin struts, and the external bracing is by streamline "wires."
   The main spars of the double-T type, in spruce, and the ribs are built up of plywood webs and flanges of grisard. The whole wing-frame is braced by spruce cross members and steel wire. Ailerons are fitted to upper and lower planes, and are balanced by small extensions projecting outwards. The control acts on the lower ailerons, and is transmitted to the upper ailerons by streamlined struts. The ailerons are hinged to auxiliary spars behind the rear main spars.
   The fuselage is of rectangular-section girder construction. The forward or engine portion is built up of four solid ash longerons, struts and cross members and four transverse members forming the engine housing ; the front and rear transverse members are of sheet steel, and the intermediary ones of plywood. The central part of the fuselage, containing the pilots and observer's posts, is formed by continuations of the ash longerons, but in this case the latter are channeled and the sides of the fuselage strengthened with plywood. The remainder of the fuselage, which is fabric covered, is built up of spruce. The usual steel wire bracing is employed in the fuselage. Two ash bearers, mounted on the four transverse frames referred to above, carry the engine.
   Provision is made for adjusting the incidence of the horizontal stabilising surface, but not during flight. It is of rectangular plan-form, built up of spruce spars and plywood ribs. The elevators and rudder are balanced by means of triangular extensions, for which portions of the tail plane and vertical fin respectively are cut away. Dual control is fitted.
   The landing gear is of the V-type, the V’s being built up of glued wood laminations. The lower extremities of the V's are connected by two cross members, one in front and one behind the steel axle, over which is a fairing. Front and rear chassis members are cross-braced by steel wires, as are the two cross members. The tail skid is of ash, and is pivoted. Cooling is by two Lamblin radiators, mounted on the landing chassis.
   The main dimensions, etc., are :- Span. 12.700 m. (41 ft. 11 ins.); o.a. length. 8-640 m. (28 ft. 6 ins.); wing area, 45 sq. m. (481.5 sq. ft.); weight, empty, 1,250 kgs. (2,756 lb.); useful load, including fuel, 615 kgs. (1,356 lb.); total weight, 1,865 kgs. (4,112 lb.); wing loading, 41 kgs./sq. m. (8-4 lb./sq. ft.); power loading, 4-650 kgs. (10-25 10.)/h.p.; speed, 200_km.p.h. (124 m.p.h.); ceiling, 6,200 m. (20,400 f t ).