Squadron Leader Slade was a Flight Commander (A Flight IIRC).
S/LDR Slade, FRASER BURSTOCK DSO ... KIA - 43416 - Wednesday, 18th August 1943 - Age 31 - Peenemunde
The London Gazette of Friday 24 September 1943 contains the following from his DSO citation:
'This officer has displayed outstanding ability and unswerving devotion in the execution of operational tasks. He completed very many sorties in the Middle East theatre, achieving much success. Since his return to this country, Squadron Leader Slade has undertaken numerous sorties against various targets in Germany and Italy. His ideal leadership and unconquerable spirit have set an example worthy of the highest praise.'
He was well on the way through his 2nd tour. I am not sure if your father was part of his regular crew, but hopefully the Wickenby Memorial will have further details. I know of (not personally) one of the Navigators on 12 Squadron that night and I believe he is still alive.