On 26 April, he assumed command of the unit after Galland was wounded. Bär possibly flew his first operational sortie with JV 44 on 27 April 1945. Flying the Me 262 A-1/U5, a six MK 108 cannon prototype, he was accompanied by "Major" Wilhelm Herget and the non-commissioned officer NCO ("Unteroffizier") Franz Köster when the trio engaged American fighters over Riem; Bär claimed one aerial victory. While not flying operationally, Bär spent most of his time giving hasty instruction to the new pilots still being assigned to JV 44. With JV 44, he achieved his final four aerial victories (3 P-47s and 1 Mosquito) on 28 April, bringing his total to 220. All told, he had achieved 16 victories in the Me 262, making him the second most successful "Jet Expert" of the war, which he finished as a Lieutenant Colonel ("Oberstleutnant").