Friday 1 October The submarine hunt in Kanholmsfjärden continued until 09.00. The naval base war diary states that there were some signs of submarine activity in the morning.1 At lunchtime, two conscript soldiers in a transport boat made a visual sighting of a submarine periscope. The surface was calm. According to Commander Rolf Blomquist, Chief of Section 1 (Operations) at Naval Base East, these soldiers were travelling in a small boat in northern Hårsfjärden when suddenly they had a clear view of a periscope at a distance of a few metres. The entry for 12.55 in the naval base war diary records the instruction: ‘Tpb 457 stay where you are, observe and report.’ At 13.05, Tpb 457 was asked to report its position DQ 0904.2

The Naval Analysis Group Report states that two observers, L and J, were travelling in a boat from Märsgarn-Furuholmen to Vitså at 12.50 (when they observed a periscope entering Hårsfjärden at the northern entrance at Alvsta Långholmar):

200-300 metres from Furuholmen, L and J saw a 0.2-0.3-metre-high wave making a V going towards Berganäs. J saw two dark pipes (0.3 metres high, flat top, 0.1 metres in diameter, and distance from each other about 1-1.5 metres) going towards Berganäs. J observed them for about one minute. After this, the two pipes [periscopes] turned towards Käringholmen [in the south]. Both L and J estimated the speed at 5 knots. W[hiskey], Z[ulu], Q[uebec], R[omeo], and F[oxtrot] all have two periscopes with flat tops. For the W[hiskey], Z[ulu] and Q[uebec] the internal distance is 1-1.5 metres).3