[Kapitän]

Thu., 4.1.40 - In front of the Channel

0600 - Qu. B F 1739 - Surfaced for venting the boat, replenishment of air supply and charging of batteries.

1131 - Qu. B F 1469 - Diving from a pair of French naval planes approaching from 90° true. Were sighted at E=7000 but because depth under keel is 23m, order to dive was not given until E=4000.
Boat cannot be leveled on an even keel and runs aground. Boat is taking damages. No bombs dropped by the airplanes.

1133 - At T=19, boat touching ground again. - 1136 - At periscope depth, boat running aground again.

Boat has taken the following damages: Water entry from the stern torpedo tube and in the NCO-quarters - fortunately, the rear battery is not discharging gases. Both electric motors and diesels, as well as, the compressor and the GHG, are temporarily put out of action. The L.I. informs me, that the pressure hull may have taken some damage as well.

All damages, except for the pressure hull, can be repaired before surfacing, by the Leak-Control-Groups I and II, the M-Group and E-Groups I and II.

1142 - Surfaced.

1200 - Qu. B F 1469 - Days Run: 74.8 sm - ↗ 47.9 sm - ↘ 26.9 sm
62 cbm. 1 Eto and 3 Ato. W7, Sea6, heavy swell from north, clear, >1000mb, good visibility, -2°C
Sunrise 1228 - Sunset 2041

1306 - Qu. B F 1466 - Smoke trail bearing 166°, E= 16000, coming up fast.

1308 - Seems to be a passenger liner traveling alone: Two funnels and two masts, one at the bow and one at the stern, speed about 13 kn, on northwesterly heading.
Changing course to 270° and GF, in order to intercept. Boat cannot go faster than 13 kn, as the sea is constantly washing over the bridge.

1345 - Qu. B F 1465 - Diving at E=8000. Turning in toward the passenger liner. Course 210° and AK.

1400 - S-Tiefe. Vessel is identified as an English mail steamer of about 5760 ts, painted in navy grey colors and traveling with dimmed lights on course 300°, however, without any apparent armament.

I decide to attack because the steamer
1) is coming from either England or France,
2) is painted in navy grey colors,
3) is traveling with dimmed lights and
4) is identified as a mail steamer and not a passenger liner.

The fact, that no armament is visible, is no guaranty, that the steamer is not armed anyways.

1403 - Single shot with tube I (G 7 e, Pi-1, K-b, magnetic fuse, running depth 10.0m):
E=550, inclination green 90°, enemy speed 15 knots, aim-off green 25°, own course 210°:
Torpedo hit after 37 Sec.!

I have estimated the enemy speed too fast, the torpedo just manages to hit the steamer at the bow.
The initial torpedo explosion is followed by several very strong secondary explosions along the entire length of the steamer. This is a very strong indicator, that this steamer was not merely carrying care packages and love letters.

The steamer sinks within 1 minute of the torpedo hit, accompanied by very violent explosions and an underwater boiler explosion. Through the periscope I can see 3-4 carley floats with survivors on them.
I decide not to surface, as I find it very doubtful, that I will be able the question the survivors with the prevailing wind and sea conditions. I also, don't want to subject the boat to another possible air attack, before performing a proper test dive. I retire to the west.

2245 - Qu. B F 1455 - Surfaced for venting the boat, replenishment of air supply and charging of batteries.

Continuing return cruise.

Gelhaar
Ob.Ltnt.z.S. & Cmdr.