The Vltavan 10 cc in-line alternate-firing glow-plug twin was not a product of the Vltavan factory in Prague, Czechia - rather, it was a well-conceived after-market combination of two 5 cc Vltavan racing engines. Beginning in 1960, examples of the twin were constructed by František Ježdík, M. Herber and possibly one or two others. I'm aware of only 5 surviving examples worldwide, although there are probably one or two others of which I have no knowledge.

Although the Vltavan Twin was designed along very practical lines from a functional standpoint, its construction required machining of the components to very high standards of accuracy. My own example is very capably constructed and would doubtless run just fine if I cared to give it a try. A contemporary test report published in a Czech modelling magazine claimed that the engine started and ran well, developing at least 0.500 BHP at a little over 12,000 RPM. The R/C throttle reportedly functioned quite effectively.

A full review of the Vltavan Twin may be found elsewhere on this website.