Polish Advanced Trainers
When Poland became an independent nation, one of the important needs was the creation of an effective air force. In the beginning the core was composed of veterans serving with the Germans and Austrians during the First World War. Soon aviators from many nations joined them to create a formidable fighting force. Still more aviators were needed to defend the promise of independence for this fledgling nation. To meet this need flight schools were created to swell the ranks of combat pilots who would defend their country and eventually fight for freedom during the Second World War.
The Morane-Saulnier A-1 had very modern lines and was very streamlined. Even though 1,210 were produced it never made a big impact at the front during the Great War. By mid-May 1918 it was withdrawn to serve as an advanced trainer, designated MoS 30. When France began aiding Poland in their efforts for independence the Morane-Saulnier A-1 was a perfect fit for use in the Polish Advanced Flying Schools.
When the MS A1 was deployed in Poland many of them retained their French markings. I am not sure if they retained the roundels on the wing or if they carried Polish markings.
This is another example of the standard French camouflage pattern. Notable it the lack of wheel covers and color change of the MS logo on the cowling.
In ths profile you see the French camouflage scheme still in use but there is a the shift to use of Polish national insignias.
This example has the dark green color we associate with interwar aircraft. One obvious change is the wide pale blue area on the fuselage. This is fairly atypical. Most late Polish aircraft use gray on the lower surfaces.