The second and permanent roundel of the
Czech-Moravian-Silesian Republic from
my Sparrow Avengers timeline.
In the mid-1930s, the process of selecting a new CMSR roundel had started anew. Both the higher ups and the regular personnel of the CMSR air force eventually grew tired of the original roundel. The main argument against keeping the pentagon was the existence of the blue field - according to many "it just didn't mesh that well with the other national colours as part of the whole combination".
Then again, decades later, some of the former air force staff and CMSR citizens claimed that the ditching of the blue field was also a covert political move : After the Silesian Falangists took control of the Kingdom of Silesia in the mid 1930s and started to openly express their irredentist agenda towards Czech Silesia, the CMSR government might have decided to remove the blue field, in order to avoid provoking a response from the falangists (since Upper Silesia's and, by extension, the Kingdom of Silesia's heraldic colours are blue/azure and golden/or). Over time, these claims have become a fairly popular (if minor) conspiracy theory. Amusingly, recent research seems to indicate that the roots of the theory might have originated in false flag rumours secretly spread by falangist agents in Czech Silesia during the latter half of the 1930s.
As an interesting "tip of the hat" to the original roundel, the outline separating the outer frame of the roundel from its inner, coloured core, was changed from white to blue. This was because the roundel's authors realized at the last minute that the white of one of the fields and the white of the line clash together, creating an undesirable visual impression. After a debate with government experts, their idea of symbolically keeping the blue colour from the original roundel in the form of the outline was approved. Still, even this last minute change has become entrenched in the whole "government changed the roundel due to fear of falangists" conspiracy theory.
Whether the official explanation for the change or the rumours surrounding it are true, the replacement roundel - called colloquially
čtyřuhelník ("tetragon") - was adopted without much fuss. Pilots, air force personnel and the general public grew almost instantly fond of it. Even today, it is remembered as "the better of the two interwar era roundels".