Latham Trimotor | |
---|---|
Role | Military trimotor flying boat |
National origin | France |
Manufacturer | Latham et Cie |
First flight | 1919 |
Primary user | Marine française (French Navy air service) |
Number built | 4 |
Developed into | Latham HB.5 |
The Latham Trimotor was a large French trimotor biplane built just after World War I and used in small numbers by the French Navy. It had three engines, the outer two in tractor configuration and the central one in pusher configuration. They could carry four "large" bombs and mounted forward and dorsal machine guns. Four aircraft were produced for service with the Marine française.
The Latham Trimotor (its Latham type number is not known) was a large biplane, with unequal span, blunted rectangular plan wings with high aspect ratio for the time. The wings were built around a pair of spars constructed from spruce and poplar plywood. They were fabric covered and in three parts, a central section attached to the upper hull and two outer sections divided into two bays with three vertical pairs of parallel interplane struts, the innermost at the junction with the central section. The upper wing centre section was supported over the fuselage by a transverse inverted V-strut to the forward longeron and by two vertical struts to the rear longeron. Outboard, the overhangs of the upper wing were supported by outward leaning pairs of struts from the feet of the outer interplane pairs; below these points small, flat bottomed floats which provided lateral stability on water were mounted. Its ailerons were balanced and mounted only on the upper wing; they were short, reaching outwards from the outer interplane struts. [1] [2]
All three 250 kW (340 hp) Panhard-Levassor 12Cb V-12 engines were mounted midway between the wings in the central section on steel frames. The outer two were in tractor configuration and the central one, mounted above the fuselage, was a pusher. They had rectangular radiators in front of them. Each drove a four blade propeller. In order for the central propeller to clear the fuselage the central engine was mounted higher than the others and the chord of the upper wing reduced to provide a trailing edge cut-away for propeller clearance. Their three 530 L (120 imp gal; 140 US gal) fuel tanks were in the fuselage forward and aft of the space for bombs, passengers or cargo; fuel was pumped from these to a feeder tank in the upper wing so that the engines could be gravity fed. [1] [2]
The hull of the Trimotor was ash framed and covered with poplar or birch plywood. The forward planing hull had soft chine, ending at a single, shallow step under the wings. Ii was divided internally into seven inter-accessible compartments. The first held a machine gunner's post in the extreme nose and the second a side-by-side open pilot's cockpit with dual controls midway between the nose and the leading edge of the wing. The flight engineer shared the third compartment with the two forward fuel tanks, with access through a dorsal hatch and lit by a porthole in the roof. The fourth and fifth compartments housed useful load and fuel respectively. In the more slender fuselage aft of the step the sixth compartment was empty but in the seventh housed the dorsal gunner's cockpit and the radio operator's cabin, lit by side portholes. [1]
The hull became slender towards the rear and curved upwards to support a biplane, constant chord horizontal tail with balanced elevators on its upper and lower planes. The lower elevator was in two parts with a central V-shaped cut-out. Between the planes were three fins, each carrying a rudder; the outer pair were trapezoidal in shape to allow elevator movement but the central one was rounded and deeper, moving in the elevator cut-out. [1]
The date of the Trimotor's first flight is not known. Though a contemporary report in August 1920 [3] noting the satisfactory completion of tests at the Latham factory at Caudebec-en-Caux and describing it as the new "High Seas" flying boat suggests a date around the spring of 1920, a modern account gives 1919. [2]
Four Trimotors were ordered by the Marine française. [1] [2] When the first was tested the Navy complained that alighting contact was very hard and so Latham revised the planing surface, giving it harder chine (a steeper V) and used this on the other three Naval Trimotors, giving then gentle landing characteristics. They could carry four "large" bombs". [1]
The Latham HB.5 of 1921 was intended as a civil development, similar but not identical in detail and powered by four, rather than three, slightly less powerful engines whilst maintaining the total power of 750 kW (1,000 hp). [1] No civil sales were made but ten were bought for military use. [4]
Data from L'Aéronautique, November 1920 [1]
General characteristics
Performance
Armament
The Latécoère 4 was a three-engined, 15-passenger biplane built in France in the early 1920s. It proved difficult to fly and was discontinued, though a second machine was completed as the Latécoère 5 bomber.
The Caudron C.251 Et-2 was a French tandem seat, open cockpit biplane designed as an intermediate trainer and built in 1931. It did not go into production.
The Caudron C.140 was a French tandem cockpit sesquiplane designed in 1928 as a combination of liaison aircraft and observer and gunnery trainer.
The Caudron C.91 was a French single engine biplane with an enclosed passenger cabin seating four. It first flew in 1923.
The Caudron C.43 was the first French five-engined aircraft, a biplane intended for passenger transport or military use and multi-engined for safety. A development of the three-engined Caudron C.39, it had one tractor configuration engine in the nose and two push-pull pairs between the wings. It was capable of carrying eight passengers but was not developed.
The Caudron C.37 was a French three-engined biplane passenger transport, built in 1920. It could carry six passengers.
The Caudron C.33 "Landaulet Monsieur-Madame" was a French twin engined biplane with four seats, two in open cockpits and two in an enclosed cabin.
The Caudron C.25 was a large, three-engined, biplane airliner, designed and built in France soon after the end of World War I. Its enclosed cabin could accommodate up to eighteen passengers.
The Heinkel HD 20 was a twin engine, three seat German biplane built in 1926 for civil survey work.
The Latham HB.5 was a French biplane flying boat with four engines in push-pull configuration pairs. Ten were used by the French Navy.
The Latham E-5 was a large French Naval four engine biplane flying boat, flown in 1925. It was successfully tested but only one was built.
The CAMS 52 was a twin-engined floatplane torpedo-bomber. It was not ordered by the French Navy and only one CAMS 52 was completed. It first flew in the summer of 1930.
The Dornier Do S was a 22-passenger flying boat airliner flown in Germany in 1930.
The Latham L.1 was a French competitor in the 1923 Schneider Trophy race. It was a twin engine, biplane flying boat, built by Société Latham.
The Caproni Ca.61 was an Italian heavy day bomber aircraft of 1922. It was the final development of the Caproni three engine, twin boom biplane types developed during World War I, but it was not put into production.
The Potez 24 A.2 was a mid-1920s French biplane intended to replace the Potez 15 as an army observation aircraft. The further improved and larger Potez 25 was preferred for production.
The CAMS 54 was a strengthened and more powerful version of the French CAMS 51 civil transport and naval reconnaissance flying boat, developed for transatlantic flights. It is sometimes referred to as the 54 GR.
The Cañete Pirata, also known as Hidro Antonio Cañete de Reconocimiento (HACR), was a Spanish military parasol wing, single-engined flying boat flown in the late 1920s. Only one was built.
The LFG V 8 Bärbel (Barbel) in English) was a small, single-engined, biplane flying boat which carried two passengers. The sole example was built in Germany shortly after World War I but was exported and used for Baltic flights.
The Zeppelin-Lindau Gs.I, often known post-WWI as the Dornier Gs.I after its designer Claude Dornier, was a civil flying boat developed immediate post-war from a military prototype. Its passenger cabin seated six. Only one was completed, and that was eventually scuttled to keep it out of Allied hands. Another of the military prototypes was intended to have a bigger, nine seat cabin and other refinements but the Gs.II was incomplete when discovered by Allied inspectors.