Cika wannan jumla: Farawa a 06:45 a kan 6 Afrilu, da "Luftwaffe" kaddamar
Operation Retribution, jerin hare-haren bama-bamai da aka shirya a kan Belgrade wanda ya yi daidai da hare-haren iska da na kasa a duk faɗin ƙasar. Yawancin raƙuman jiragen saman Jamus sun kusanci Belgrade a cikin yini, da farko Junkers Ju 87 "Stuka" masu jefa bama-bamai masu nutsewa tare da mayakan. Dukkanin Bf 109E-3s na 51st Fighter Group sun yi tsere don saduwa da hare-haren farko, kuma ba da daɗewa ba Messerschmitts na 32nd Fighter Group suka shiga. Matuka jirgin sama na 102 na 51st Fighter Group sun yi da'awar bakwai, sun rasa jiragen sama guda biyar a dawo. Kungiyar 32nd Fighter Group Messerschmitts ta yi ikirarin wasu bama-bamai guda hudu don asarar biyu daga cikin nasu, kodayake wasu mayakan Yugoslav da yawa sun sami rauni kuma sun lalace. A lokacin tashin hankali na farko, bindigogin anti-aircraft na Yugoslav sun harbe kan Yugoslav Messerschmitts da na Jamusawa, ba tare da iya bambance su ba.