Walter Mikron

Mikron
Walter Mikron III
Type	Inline piston engine
National origin	Czechoslovakia
Manufacturer	Walter Aircraft Engines / Parma Technik
First run	1938

The Walter Mikron is a four-cylinder, air-cooled, inverted straight engine for aircraft.

Developed in Czechoslovakia in the early 1930s. The engine saw limited use in late 1930s and early 1950s. In 1980s initial batch of engines was rebuilt by Aerotechnik Moravska Trebova for use on L-13 Vivat motorgliders. Production of new engines followed. The company Aerotechnik was later bought by Parma Technik and the production continues since 1999 under new name in the same factory. The engine is mostly used on ultralight, LSA and experimental aircraft. The production is about 20-30 engines annually. (2014)

Initial production engines producing 37 kW (50 hp). 16 engines produced in 1935.

The Mikron II, released in 1936, had a bore of 88 mm (3.46 in) and displacement of 2.336 l (142.55 cu in), delivering 45 kW (60 hp) at 2,600 rpm max continuous and 46 kW (62 hp) at 2,800 rpm for short periods. After a hiatus in production during the Second World War, production resumed till 1948, when the Micron III went into production. In total 421 Mikron II engines were produced.

With a displacement of 2.44 l (148.90 cu in), compression ratio 6:1, it produces 48.5 kW (65.0 hp) at 2,600 rpm. Introduced in 1945, 103 engines made between 1948-1950. The engines were used on Praga E-114 Air Baby.

In 1980s company Aerotechnik in Moravska Trebova had collected 56(!) engines of the post war production. The engines have been rebuilt, new pistons and carburetor JIKOV SOP 40L installed. Used on L-13 Vivat motorgliders.

Engines produced by Aerotechnik in 1980s-90s. Updated cylinder head with one more cooling rib, updated connection rod lower end, otherwise identical with IIIS.

Improved version of the Mikron IIIA 56 kW (75 hp) at 2,750rpm for 5 minutes, max continuous power of 51 kW (69 hp) from 2.44 l (148.90 cu in), compression ratio 7.2:1, bore 90 mm (3.54 in), stroke 96 mm (3.78 in), dry weight 69 kg (152.12 lb) Almost identical with IIIA except the compression ratio. The engine initially used lowered A heads. After some problems with cracking, new B heads were developed by Parma Technik.

Engines equipped with electric starter and alternator.

60 kW (80 hp) at 2,800rpm from 2.7 l (164.76 cu in), bore 93.3 mm (3.67 in), stroke 96 mm (3.78 in). Version developed by Parma Technik for ULL and experimental aeroplanes.

Data from Jane's All the World's Aircraft 1938

A Walter Mikron II, in the Deutsches Museum Flugwerft Schleissheim

...
Wikipedia