The Junkers Ju 60 was a single engine airliner built in prototype form in Germany in the early 1930s.
It was designed to meet a requirement issued by the Reich Transport Ministry for a German-built equivalent to the Lockheed Vega with which to equip Deutsche Luft Hansa.
The result was a sleek, cantilever monoplane of conventional configuration, with wings skinned in the corrugated duralumin that had been a hallmark of Junkers designs up to this time, although this would be the last Junkers aircraft to have this feature.
The main units of the tailwheel undercarriage were retractable.
The Ju 60 was evaluated by Deutsche Luft Hansa against the Heinkel He 70.
With the latter able to demonstrate a top speed 75 km/h (47 mph) better than the Ju 60, development of the Junkers design was halted before the third prototype had been completed.
The two examples that had already been constructed eventually saw service with the Luftwaffe as liaison aircraft until 1942.
The work done on the design would later form the basis of the Ju 160.
Junkers Ju 160
The Junkers Ju 160 was a German single engine, low-wing six-seat passenger transport aircraft developed from the Ju 60 and targeted at the same fast airliner market as the Heinkel He 70 and the Lockheed Model 9 Orion.
The Deutsche Lufthansa fleet of 21 aircraft began operations in 1935 and continued until the start of World War II.
The earlier Ju 60 from which the Ju 160 was developed was not fast enough to compete with the Heinkel He 70 and only about three were used by Lufthansa in the period 1933-6.
The Ju 160 was cleaned up aerodynamically and had a more powerful engine, that combination making it about 72 km/h (45 mph) faster.
Like the Ju 60 and in the Junkers’ tradition, the Ju 160 was a low-wing cantilever design, the wings being built around twin duralumin spars and covered in sheet duralumin.
For the first time, though, a Junkers aircraft used entirely smooth skinning; the Ju 60 had a smooth-skinned fuselage but the traditional corrugated flying surfaces.
The improved performance of the Ju 160 was in part due to this change of skinning.
The wing planform was also revised to have taper only on the leading edge.
The trailing edge carried the usual Junkers “double wing”, a full-width adjustable flap cum aileron arrangement.
Other aerodynamic improvements included a cockpit enclosure better faired into the fuselage and a seriously revised undercarriage which now retracted inwards into the underside of the wing where the wheels were completely enclosed.
The Ju 60 undercarriage left the wheels partially protruding in Douglas DC-3 fashion on retraction.
Finally, the power was increased by 10% with a 490 kW (660 hp) BMW 132E radial engine.
Seating was for six passengers in two forward-facing and one rear-facing pairs.
The crew, pilot and radio operator sat in tandem in an enclosed cockpit with rudder pedals, folding control column and seat for a second pilot to starboard.
The first prototype Ju 160 V1, D-UNOR, was taken from the Ju 60 construction line and first flew in January 1934.
Lufthansa used it in trials and a number of changes were made to the final prototype (V3), including a wider chord, less deep rudder and a faired tailwheel plus minor door modification.
The first civil production series were designated Ju 160 A-0.
The second prototype V2 was for a military version.