Chizhevski BOK-1

BOK-1
Role High-Altitude research aircraft
National origin Soviet Union
Designer Vladimir Chizhevsky
First flight summer 1936
Number built 1
Developed from Tupolev RD

The BOK-1 (Byuro Osobykh Konstrooktsiy - bureau of special design), (a.k.a. SS (Stratosfernii Samolyet – stratospheric aircraft)), was an experimental high-altitude aircraft designed and built in the USSR from 1934.