Bulgarian Air Force MeBf 109G "Gustav", flying in formation, 1943/'44.  JR.

Bulgarian MeBf 109.

Unlike its (very obvious) biplane predecessor, the Avia B-534, the Avia B.135 was, it would appear, Czechoslovakia's proposed first generation fighter monoplane.  It came far too late to make any significant impact in WW2.  Most (if not all) of the tiny production run (the only one) appear to have been bought by the Bulgarian Air Force; which found that the purchase had been a bit premature, since the B.135 revealed serious engine reliability "issues" that were never resolved.  As a result, this fighter - which undoubtedly had great potential, was confined to a fairly gentle training role for the most part.  There is one account of a possible encounter with US bombers in 1944 - but I am not confident to confirm this.  Best regards, JR.