The following day, one IK-2 force landed due to engine failure, reducing the number of serviceable IK-2s to five. Despite deteriorating weather conditions and revolts within the Yugoslav forces, combat patrols continued. At 12:00 on 11 April, all aircraft were grounded by the weather. On 12 April, aircraft of the 4th Fighter Regiment took to the air again, chasing German reconnaissance aircraft, but the IK-2s did not record any victories. The following day, the 4th Fighter Regiment continued carrying out sorties, but around 12:00 the commander of the 2nd Mixed Air Brigade ordered the remaining aircraft of the 4th Fighter Regiment to be destroyed, and all personnel to withdraw via road to Sarajevo.