PZInż. Major

Major
Type	Inline piston engine
National origin	Czechoslovakia
Manufacturer	Walter Aircraft Engines
First run	1934

Walter Major was a family of Czechoslovak aircraft inline engines developed by Walter Aircraft Engines in the 1930s. Available in either four or six cylinder configuration, with identical bore and stroke of 118 mm (4.6 in) and 140 mm (5.5 in), respectively, the Walter Majors were primarily used in light aircraft. License-built in Poland by the state-owned Państwowe Zakłady Inżynieryjne (as the PZInż. Major 4), the engine was used in, among others, Zlin Z-XIII, RWD-11 and one of the PWS-35 Ogar prototypes.

Data from [1]

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