thank you Archie.....
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Since March 1942, the squadron, named "Sonderstaffel Buschmann" ("Special Squadron Buschmann"), made combat sorties with the tasks of patrolling the Gulf of Finland for the detection of Soviet submarines. The PTO-4 aircraft were not equipped with radio stations and did not have airborne weapons. During this period, the pilots did not have uniform uniforms - some wore the Luftwaffe uniform without insignia, others - the Estonian military uniform of the period until 1940, and still others - generally civilian clothes.
By the beginning of the summer of 1942, the "Special Squadron of Bushman" was armed with four RT-4s (SB + AA, SB + AB, SB + AC and SB + AD), one Miles "Magister" (SB + AF) , one De Havilland DH-89A Dragon Rapide (SB + AH) and one RWD-8 (SB + AJ). In addition to them, the Germans handed the squadron four more Stampe SV-5 - Belgian training biplanes, ten of which, at one time, were collected under license in Latvia. However, it soon became clear that the Stampe SV-5 was completely unsuitable for flights over the sea, and therefore they were replaced by German He-60s the same summer.