According to wiki the one I was thinking of was the Ka-50
> The single-seat configuration was considered undesirable by NATO. The first two Ka-50 prototypes had false windows painted on them.[19] The "windows" evidently worked, as the first western reports of the aircraft were wildly inaccurate, to the point of some analysts even concluding its primary mission was as an air superiority aircraft for hunting and killing NATO attack helicopters.[20]