The Junkers F 13 was the world's first all-metal transport aircraft, developed in Germany at the end of World War I. It was an advanced cantilever-wing monoplane, with enclosed accommodation for four passengers, and a two seat open-air cockpit. 322 planes of the type were manufactured, which was exceptionally large number for a commercial airliner of the era, and were operated all over the globe. It accounted for over a third of air traffic in the early 1920s. It was in production for thirteen years and in commercial service for more than thirty. There were many versions including floatplanes for water landing, skis, mailplane, and different engines. Several survived in various states of repair in museums, and a replica of the type was put back in production in the 2010s;taking flight once again nearly a century after it first flew. The F 13 was a very advanced aircraft when built, an aerodynamically clean all-metal low-wing cantilever (without external bracing) monoplane. Even later in the 1920s, it and other Junkers types were unusual as unbraced monoplanes in a biplane age, with only Fokker's designs of comparable modernity. It was the world's first all-metal passenger aircraft and Junkers' first commercial aircraft. The designation letter F stood for Flugzeug, aircraft; it was the first Junkers aeroplane to use this system. Earlier Junkers notation labelled it J 13. Russian-built aircraft used the designation Ju 13. Like all Junkers duralumin-structured designs, from the 1918 J 7 to the 1932 Ju 46, (some 35 models), it used an aluminium alloy (duralumin) structure entirely covered with Junkers' characteristic corrugated and stressed duralumin skin. Internally, the wing was built up on nine circular cross-section duralumin spars with transverse bracing. All control surfaces were horn balanced. Behind the single engine was a semi-enclosed cockpit for the crew, roofed but without side glazing. There was an enclosed and heated cabin for four passengers with windows and doors in the fuselage sides. Passenger seats were fitted with seat belts, unusual for the time. The F 13 used a fixed conventional split landing gear with a rear skid, though some variants landed on floats or on skis. The F 13 first flew on 25 June 1919, powered by a 127 kW (170 hp) Mercedes D IIIa inline upright water-cooled engine. The first production machines had a wing of greater span and area and had the more powerful 140 kW (185 hp) BMW IIIa upright inline water-cooled motor. For more details of the development and design, operational history, variants and replicas under construction, click here. Three examples came to this region. An F 13ke VH-UTS (c/n 2074 – ex SE-AEC) was operated by the Lutheran Mission from 27 February 1935, later going to the Rheinische Mission in Dutch New Guinea in September 1939. The second aircraft, an F 13L, VH-UKW (c/n 2044), was imported by Eyre Peninsula Airways Ltd, arriving in Melbourne, VIC on 19 June 1929 from Hamburg. It was used on passenger services for a period, including a service to Broken Hill, NSW, which commenced on 15 January 1930. It was then used by Goldfields Air Navigation Ltd of Kalgoorlie, WA. In December 1931 VH-UKW was obtained by Guinea Airways for passenger and mail services between the Goldfields and Port Moresby, PNG. At about this time the 287 kw (385 hp) Junkers L-5 engine was replaced by a 336 kw (450 hp) Bristol Jupiter engine for fleet standardisation. It continued in service in New Guinea but was not evacuated at the time of the Japanese attacks, being destroyed by enemy action in March 1942. The third aircraft, also an F 13L, VH-UPL (c/n 2075), was imported by Bishop & O’Sullivan Aircraft Service which operated as Sky Travel (Australia) Pty Ltd. It arrived on board the ‘SS Tancred’ on 28 October 1930 and was assembled at Essendon, VIC. It was the first aircraft in Australia equipped for night flying. It was test flown on 1 November 1930 by Captains W Roethe and T R Young at Point Cook, VIC and, named ‘Glorious Queensland’, was flown to Brisbane, QLD, arriving on 1 November 1930. VH-UPL was flown to Sydney, NSW, then back to Eagle Farm, QLD, and commenced a weekly passenger service from Brisbane to St George, QLD and twice weekly services to a number of other centres, at Goondiwindi, QLD using a salt pan for a landing strip. It also made joyflights to promote the service. However, services were suspended on 15 February 1931 due to lack of patronage and the aircraft was flown to Melbourne. Whilst flying in bad weather over the Bethungra Ranges on 28 August 1931 the magneto drive on the engine failed and a forced landing was made at Illabo, NSW, where repairs were effected. After arrival in Melbourne it was dismantled and shipped to South Africa, where it became ZS-ADR in June 1932 with Union Airways.
