SZD

The abbreviation stands for SZD:

Sowetskije schelesnyje dorogi, the state railway company of the Soviet Union
Glider type of the Polish manufacturer PZL Bielsko ( Szybowcowy Zakad Doświadczalny ), PZL Bielsko SZD- for example, 50, see List of types of aircraft / N S # PZL Bielsko

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