At daybreak, the Allies and Germans exchanged signal lamp messages, with the Germans repeatedly requesting to be taken off as they were unable to stay afloat, and the British refusing to evacuate them until the Germans secured the submarine and stopped it from sinking—the British were concerned that the Germans would deliberately leave behind them a sinking U-boat if they were evacuated. The situation became more confused when a small float-plane, (a Northrop N-3PB of 330 (Norwegian) Squadron), appeared. Unaware of the surrender, it attacked "U-570" with small bombs and fired on "Northern Chief", which fired back. No damage was done and "Burwell" ordered the aircraft away by radio.