the "luftwaffe" was also engaged in applying pressure to soviet naval forces. on 18 june the cruiser "kharkov" was severely damaged. attacks on 19 june by kg 51 destroyed the anti-aircraft platform in severnaya bay, allowing air operations to continue unopposed. the lack of anti-aircraft cover made it impossible for the minelayer "komintern" to enter the harbour with reinforcements. the lack of supplies resulted in soviet ammunition and fuel supplies slipping to critical levels on 20 june. the luftwaffe was experiencing shortages of its own. the daily average of sorties was now reduced by 40 percent. due to the shortages of bombs, all ordnance had to be dropped individually to minimise wastage. some experienced crews had to conduct dive-bombing attacks 25–30 times a day. kg 51's ju 88 crews in particular had felt the strain.