1939/40 Patrols on the east coast of England, I have several times, reported convoys then dived to engage,
The Luftwaffe usually shows up after half an hour or so in random numbers and proceeds to bomb the convoy / get shot down.
Just wish the fly boys would get the idea that if there are sinking wrecks and oil slicks behind the convoy, then it indicates that I am in the area and if they take out the remaining escorts then I can deal with the rest with the deck gun.
But Noo they have to go for the biggest merchants they can find