September 17 (cont)0217 first sound contacts are heard in ENE. We're heading NW so we already nearly have the interception course.
By 0300 ours it becomes evident that this is no single ship but a convoy! There are many different engine sounds, high and low revolutions. U-46 surfaces and speed to intercept them!
30 minutes before visual contact:
0419 visual contact!!! Looks like we failed to arrive before the convoy, but the first ships of the starboard-most column are in sight. 3 warships are heard: one is either in the middle or across the convoy, second is well ahead of it and the last seems to be guarding the rear. The one in the rear has a different engine sound and is probably possibly a frigate.
Above:the ships in sight seem to be mostly small cargo ships and merchies. Fine, we'll take what we're given. U-46 submerges and begins the approach. Maybe from closer range we'll see some juicier targets, or perhaps there are some in the closest column as well?
U-46 sneaks in. At a distance of 1000 meters, all 4 torpedoes are fired!!!
Targets are a large ship(he biggest one in sight) and a poor coastal freighter that just happened to be in the wrong place in the wrong time. Definitely not worth a torpedo let alone 2 if it were sailing alone, but if we are to shoot something in a convoy, then its better to fire everything at once, before the escorts are alerted. The speed of the convoy is estimated at 4 knots, which is very slow indeed! The firing solution is almost perfect: 1000m to first target, 2000m to second, 90 port AoB and dead ahead.
In the dark, there is no way they could have seen the bubble trails.
Below: torpedo impact!! The poor freighter receives 2 hits...
Seconds later, the large ship behind the first one is hit, and immediately sinks in less than 2 minutes!
U-46 now turns around to leave the convoy and to fire the 5th, stern, torpedo tube. This could have went better: the solution is hurried with the range simply estimated to be the same as the large merchant in the 2nd column had, AoB is left where it is and the tube is fired as the submarine is turning!! By waiting another 15 seconds it would have been possible to shoot at the closer targets. There were 4 ships aligned so that one of them would have been hit for sure, but now the stern torpedo went after the lone ship.
The Kaleun cursed himself as the torpedo sped away... (below, bubble trail arcs to starboard, notice the bearing indicator's reading...)
Nearly 4 minutes later, the Kaleun was still looking around for enemy escort warships through the periscope(below, a frigate!!).
Just as he pulled the lever to lower the periscope, the torpedo hit and went off!! 4 minutes and 12 seconds after being fired!
04.42 order was given to dive to 100 meters at a speed of 2 knots. U-46 disappeared into the darkness...