F.d.U./B.d.U.'S War Log

1 - 15 December 1940

PG30278

     
 
 
 
Date
Position, Wind, Weather
 
and
Sea State, Illumination,
Events
Time
Air Pressure, Moonlight etc.
 
 
 
 
1.12.
  Positions of our own boats at 0800.
1)  In the operations area W of the North Channel:
 
U 140
AM 18;
U 94
AL 37
 
104
19;
43
55
(Weather boat)
103
41;
101
58
 
99
47;
95
65
 
52
68
 
  Italian U-boats:
  J 13 - AL 39
  J 26 - AL 68
  2)  West of Spain and Portugal:  U 37, 65, (Freetown).
  3)  On return passage home:  U 29
                "            "          to Lorient:  U 47 (still in the                                                                        operations area)
                 also J 2, 18 and J 14 (still in the operations area)
  4)  In Lorient:  U 38, 96, 100, 123, 124.
          " Kiel:  UA, U 46, 48, 96.
          " Bordeaux:  J 1, 3, 4, 6, 7, 8, 9, 10, 12, 15, 16, 17, 20, 22, 25.
  Ready for operations by December 15:  U 96, 100, 124 and several Italian U-boats.
   
  In order to strengthen the disposition in the direction SW of the North Channel U 104 moved further south at midday and U 140 to a position directly off the North Channel (into the area which U 137 reported as a scene of considerable activity).  On the same day U 101 made contact at 1800 with an inward-bound convoy in square AL 5883.  The positions of all the boats are very favorable as regards this convoy.  U 101 was the boat furthest west, and made contact and all other boats are within range.  Some of them have the chance to reach it the same night, while all the others should be there at latest by the following night, provided, of course, that contact is maintained.
  U 101 was ordered not to attack herself until the other boats had arrived.  She shadowed the convoy until the following morning, then reports "All torpedoes used" Diesel breakdown.  There must have already been other boats at the convoy.  U 101 was ordered to shadow until other boats had taken over.  All boats were ordered to report if they were in a position to attack so as to clarify the situation.
   
2.12.
  U 52 and 47 reported: yes.  It was to be assumed however that U 95 was also in the vicinity, as she had requested beacon signals.  U 99 also came up.  She reported at 0940.  An auxiliary cruiser sunk.  According to radio Intelligence, this was "Caledonia".  Contact was nevertheless lost for the day.  Apparently there were strong A/S and escort forces with the enemy.  The great thing was to establish contact.  This couldn't be done:
 
a) by the boats themselves.  For this it was necessary to know approximately their present position.  Only U 47 and 43 however replied to the order to give their position.  U 94 was still some
  
     
 
 
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Date
Position, Wind, Weather
 
and
Sea State, Illumination,
Events
Time
Air Pressure, Moonlight etc.
 
 
 
 
    distance off.  U 47 and 43 S and NW respectively astern of the convoy.
  b)  Or by a/c of which unfortunately only a very few were available:
            One FW 200 from KG/40 Bordeaux
            Two BV 138 from Brest, Group 406.
    They did not make contact.
    The situation therefore remained obscure during the day.  This operation shows up the gaps which inevitably result from warfare with so few U-boats.  It is necessary to concentrate these few available U-boats against the enemy formation, once it has been detected, if any major success is to be achieved.  There are not sufficient boats to make at all sure that the enemy will be held.  The U-boats slow speed and small visual range make things difficult anyhow.  But is is equally clear that these gaps can be very effectively filled, as far as making contact goes, by using a/c.  Even a few isolated reports would be of greatest value.  But there are only 2 BV 138 from GAF Coastal Group 406 available for this task and one FW 200 from KG 40, which is used for this purpose by arrangement with the Group.  Success is correspondingly small:  they did not make contact.
    At 1644, U 94 sighted the convoy.  All boats were ordered to operate, even U 101, who has no torpedoes left.  It is vital to shadow until night fall.
    U 43 sighted several Outward-bound ships while still 60 miles away from the convoy.  She pursued them and was drawn away to the west.  She sank 2 totaling 20,000 tons.
    At 2348 U 94 reported:  convoy dispersed.
    From all reports received by morning it was seen that the following were sunk on December 2:
   
By
U 94
- 3 ships
totaling
21,000
GRT
 
101
- 5 ships
"
41,000
"
 
95
- 2 ships
"
12,000
"
 
99
- 3 ships
"
29,698
"
 
52
- 3 ships
"
?
 
47
- 2 ships
"
17,000
"
 
   
6 boats
  18 ships  
120,698     GRT
 
   
    Including the auxiliary cruiser sunk by U 99, but excluding the tonnage of the 3 ships sunk by U 52.
  Damaged:  U 101 - 2 ships totaling 10,000 tons.  One of these may have been sunk by U 99.
  A Radio Intelligence report suggests that another steamer was torpedoed near the North Channel.  The name of the ship is not known.  She can only have been torpedoed by U 140.
  U 103 was operating against the convoy, apparently without contact her behavior will have to be explained when she returns - also U 104, whose long silence despite orders to report, gives cause for concern.
   
      U 100 sailed for the operations area.
   
13.2.
  The attack on the convoy must be regarded as ended.  U 47, 95, 101 are returning (torpedoes used or lack of fuel).
  U 43, 103, 104 must be expected to return soon.
 
U 99, 52 and 94 can remain in the operations area for some time.
 
  I am assuming that the enemy will for the next few days avoid the area in which the last attack took place.
 
 
   
 
 
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Date
Position, Wind, Weather
 
and
Sea State, Illumination,
Events
Time
Air Pressure, Moonlight etc.
 
 
 
 
  My assumption was confirmed by an opportune Radio Intelligence (X) report, which stated that 2 inward-bound convoys are being re-routed, one of them hauling out far to the north, the other SC 13, evading to the south along a route about 70 - 120 miles S of the route taken by the scattered convoy.  Here we have an enemy report which is reliable, judging from all previous experience, but unfortunately does not give any details of time.  I decided nevertheless to operate the 5 boats still in the operations area, realizing that they may have to wait for several days.  The boats are disposed in deep formation along the convoy's route.  In the west are 2 boats on the same longitude so as to have a better chance of intercepting the convoy.  There are only 5 boats including the weather boat, 2 of them will probably have to return soon and only one other U 101 is on outward passage to the operations area.  So that the regular Radio message from the weather boat will not give away the disposition, the weather reports are temporarily to be taken over by an Italian boat.  
 
  Air reconnaissance detected a convoy inward-bound immediately off the North Channel.  There was no question of U-boats operating as it would be in the North Channel, long before they reached it.  When a/c returned the convoy's position was shown to be 50 miles out.  This is an example of the various difficulties which still arise in cooperation between a/c and U-boats.  They can probably only be overcome by maintaining close contact and by a training directed to achieve the common aim.
   
4.12.
  U 96 left Kiel for the operations area.
   
  U 103 reported 6 steamers totaling 31,470 GRT sunk (at sea since November 9).
   
  No report from U 104, but there has been a U-boat warning for the area in which she may be.  
   
  As no weather reports have been received from the Italian boats, I find myself forced to detail one of our boats for this.  It will have to be one of the 5 in the attacking positions ready for the convoy, announced by Radio Intelligence.  This is very undesirable, but I have no alternative.  I do not think any danger need be feared from the probably very inaccurate bearings of the undivided short weather reports, but when there are many regular reports made from approximately the same area, the enemy is likely in the end to discover this boat's ops. area.  This, new very modest attempt to cooperate with the Italians has failed.  Two of them were ordered to make the weather reports.  Neither of them produced messages which were any use.  
  This is unfortunately not the only disappointment  I did not expect that the Italians would at once sink a lot of shipping.  They are still too unaccustomed to this theatre of operations.  They have never yet operated in similar waters under similar weather conditions.  They are not adequately equipped for it.  But I did at least hope that they would contribute to a better reconnaissance of the operations area.  In actual fact during the whole time I have not received one single enemy report from them on which I could take action.  All they have produced are several very delayed, mainly incomplete or inaccurate sighting reports.  They have never managed to maintain contact even for a very short time.
  During the period in which the German boats sank 26,000 GRT in the same operations area, the Italian successes amounted to 12,800 tons at the best (8,000 of these doubtful) and one destroyer.
  
             
     
 
 
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Date
Position, Wind, Weather
 
and
Sea State, Illumination,
Events
Time
Air Pressure, Moonlight etc.
 
 
 
 
  I am not at all sure that their presence in the operations area of the German boats, the way they let themselves be sighted, their radio traffic, their clumsy attacks do not do us more harm than good.
The main reasons for their failure are:
 
1. They do not know how to attack unnoticed or to remain unseen.
2. They do not understand how to haul ahead of a slower enemy.
3. They have no idea of night surface attack.
4. They understand nothing of shadowing and reporting.
  The attitude of the Navy Department in Rome put paid to my intention to give them the opportunity to learn the basic principles of procedure in sight of the enemy, under guidance of German Officers.
  My attempts to make use of them for warfare off the North Channel have proved in vain.  They do not serve any practical purpose.  From the point of view of the war, as a whole this can only be regretted.  I think that in the end the real reasons for their failure lies with the personnel.  They are not sufficiently hard and determined for this type of warfare.  Their way of thinking is too long-winded and lacking in initiative to allow them to adapt themselves readily and simply to the changing conditions of war.  Their personal conduct lacks discipline and they cannot keep calm in face of the enemy.
  In view of all this, I am forced to detail and operate the German boats without regard for the Italians.  It is to be hoped that the Italians will benefit with time to an increasing extent from opportunities arising for them out of this.
   
5.12.
  U 99 reported wind 10 and 11 from the operations area.
   
6.12.
  Weather continues very bad in the operations area.  Use of armament cannot be expected.
   
  U 47 and 95 entered port.
  Both boats had bad weather for the whole time they were in the operations area and were able to achieve only little success, Lieut (s.g.) Schreiber C.O. of U 95 on the whole carried out his first patrol well.  He acted with decision and tenacity but unfortunately also made several mistakes.
   
  U 100 has been allocated to ops. area within the disposition for the expected convoy.
   
  There have been a great number of SOS reports from Merchant Ships in the area west of England, which gives some indication of the routes at present in use.  It is interesting to note that there is still traffic far to the north, about 59 to 600 N.
   
7.12.
  Air reconnaissance W of Ireland was not flown as the a/c could not take off owing to weather conditions.
 
      U 140 reported:  no use of armament because of weather.
       
 
8.12.
  A Radio Intelligence (X) report shows beyond doubt that a radio message from a U-boat (U 99) from about 200 W was D/F'd.
        
      
                 
 
 
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Date
Position, Wind, Weather
 
and
Sea State, Illumination,
Events
Time
Air Pressure, Moonlight etc.
 
 
 
 
  The bearing was 70 - 100 miles out.
 
  According to Radio Intelligence S.S. "Farmsum" has been torpedoed.
   
  A U-boat warning for square CF 5159 point to activity by U 37.
   
9.12.
  U 99 reported that she was returning because of engine damage.  U 103 is returning having sunk 3 steamers totaling about 46,000 tons.  The C.O. has now passed the 100,000 ton mark.  It is possible that after all the expected convoy has got through.  The disposition of the 4 U-boats remaining in this area has therefore been loosened and they are to patrol N-S in the area in which they are at present concentrating.  Air reconnaissance by a/c of Group 406 (BV 138's) has had to be abandoned for the present because of technical defects in this type of a/c (probably for about 2 months).
   
10.12.
  U 93 was slightly damaged in dock in Lorient by several bombs which fell in her vicinity.  Pressure hull penetrated at several points by shrapnel.  Her date of operational readiness will be delayed for about 3 weeks.  Otherwise nothing to report.
   
11.12.
  U 96 has been detailed as weather boat, as the G.A.F. cannot do without weather reports from U-boats.
   
  U 100, 43 and 52 reported no traffic and U 94 slight traffic only but U 96 made contact at 1620 with an inward-bound convoy in square 2379 pursued it to square AM 3914 and scattered it.  She sank 4 ships totaling 30,000 GRT.  This is an excellent performance for this new boat.  The only other boat in the vicinity was U 140 and U 96 was ordered to bring her up.
   
12.12.
  U 140 is returning to Bergen having sunk 3 ships totaling 15,700 GRT.
   
  U 99 and 103 entered Lorient.  Otherwise nothing to report.
   
  U 100 temporarily acting as weather boat for U 96.
 
 
13.12.
  U 43 started on her return passage.  She has sunk another 6,000 GRT and altogether 3 steamers totaling 26,000 GRT.  
       
      The Italian U-boat ARGO is the first Italian U-boat to complete a really satisfactory patrol in the area W of the North Channel.  She severely damaged the Canadian destroyer Saguenay and sank one 12,000 GRT steamer.
       
      Reports from both the Commanding Officers who have returned show that U-boat operations in the North Atlantic at this time of year are very severely hampered by weather conditions.  Nevertheless U 103 sank 8 ships totaling 46,000 GRT in barely 5 weeks and U 99 4 ships totaling 34,900 GRT in 16 days.  I am always reconsidering whether it would not be more profitable in winter to transfer the theatre of operations further south into calmer areas and I always come to the conclusion that in spite of the bad weather in the north, as enemy traffic is more concentrated there, more can be sunk within a given time than in the south.  Only the amount of tonnage is of real importance for the final outcome of the war and I have therefore stuck to the north as the main center 
   
  
       
 
 
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Date
Position, Wind, Weather
 
and
Sea State, Illumination,
Events
Time
Air Pressure, Moonlight etc.
 
 
 
 
  of U-boat operations.  It is of course desirable to worry the enemy in other areas and achieve a diversionary effect.  This would relieve pressure in the main theatre of war, but it is no way to defeat the enemy.  The forces required for this should in the first place consist of those which are less suitable for the main task, i.e. the annihilation of enemy merchant shipping.  However, the central Atlantic operations area must not be neglected altogether and experience of this area for U-boat operations must be obtained and information as to the success which can be achieved there.  U 37 and 65 will be quite sufficient for this purpose at present.  All the other boats will go to the north for the time being.
 
14.12.
  U 43 hit S.S. "Orari", 10,300 GRT with her last torpedo on her return passage in square BE 2442.  The steamer did not sink however and proceeded on at slow speed.  There are none of our boats in the vicinity, but the steamer is within range of the G.A.F. (Condor a/c).  Apart from the desirability of sinking this damaged, valuable steamer, I am anxious to consolidate cooperation with the G.A.F. by a success to which the U-boats have contributed and to test the practicability of bring up aircraft by means of U-boat reports.  U 43 was ordered to shadow as far as her fuel stocks would permit and also to make beacon signals from dawn onwards and make a weather report immediately.  KG 40 promised to send out an aircraft.  The take off was delayed however, until 1100 and the aircraft could not reach the target before 1400 - 1500.  U 43 reported that she was forced to continue her return passage because of lack of lubricating oil.  I very much regret this failure of my plan, especially as every individual success attracts the attention of the authorities which would be concerned in the organization of a large-scale cooperation and proves its practicability better than theoretical exposition can.
  Cooperation is necessary
  The war has shown that the tactics of operating several U-boats together against a convoy are correct and lead to great success.  In all cases however the first contact with the convoy was a matter of chance.  The convoy approached a U-boat.  In other cases, when this did not come off, the boats were at sea for days to no purpose.  Time was wasted in the operations area.  Full use of the U-boats against the enemy is not being made because of the lack of any form of reconnaissance.
  B.d.U. is aware that Naval War Staff has been advocating the necessary reconnaissance with the G.A.F. Ops. Staff for a long time.  B.d.U.'s views on cooperation with the G.A.F. are as follows:
 
a) The U-boat is not suitable for reconnaissance.  Its height of sight is too low.  It is too slow to be able to cover a large sea area in a short time.  We have not got the necessary number of U-boats.  To use them for this purpose also means wasting their striking power.  The U-boat can achieve much more if it does not have to hang around for weeks waiting for its prey to turn up, but, by means of previous reconnaissance, can be directed to the area where the enemy actually is.  Every arm, except the U-boat arm, has its own means of reconnaissance.
b) By extensive reconnaissance the G.A.F. can provide us with definite information as to the whereabouts of the enemy, and can thus provide Ops. Control with data on which to base the disposition of the U-boats.
c) It can also support the immediate operations of the U-boats by flying exhaustive reconnaissance of the area where the boats are disposed, by reporting the valuable targets immediately and thus ensuring that enemy units within range are actually attacked and
  
                         
     
 
 
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Date
Position, Wind, Weather
 
and
Sea State, Illumination,
Events
Time
Air Pressure, Moonlight etc.
 
 
 
 
   
  that no enemy formations pass through the area occupied by U-boats without their even detecting them because of their small visual range.
d) But cooperation between a/c and U-boats does not end with pure reconnaissance.  The a/c should shadow by day until the boats reach the enemy, they should bring up the boats by making beacon signals, they should regain contact after first light of the next day, etc,.  It is therefore a question of closest tactical cooperation for a single operation.
e) The a/c's own attack on Merchant Shipping traffic is in no way hampered by fulfillment of these requirements.  It can only be an advantage to the U-boats if these a/c attack and sink and damage ships, worry, divert and scatter the enemy.
  The areas in which the U-boats are stationed are definitely promising for a/c attacks, because the boats occupy the busiest areas.  The a/c attack is not affected even if the U-boats are in the immediate vicinity.  The only thing which the a/c may not do is to attack S/M's.  Experience has shown that the danger of mistaking enemy S/M's for our own U-boats is too great to permit the a/c to attack even if it is certain that it is dealing with an enemy S/M.
f) The best thing would be to discuss this form of cooperation directly with the G.A.F. units concerned and try it out in practice.  Put in order to make cooperation really effective it is necessary
  1) to have sufficient forces.
  2)  to have a clear ruling as to authority and subordination.
  As soon as a convoy has been sighted from the cooperation, such as shadowing by the a/c making beacon signals, must be controlled by the man who is controlling convoy operation without encroaching upon the tactical leadership of the G.A.F. Officer Commanding.  This means that B.d.U. must decide where reconnaissance is to be flown and how many a/c are to be used in each case and have the available means at his disposal if a unified and rational method of cooperation is to be achieved.  Close cooperation has so far been carried out with the following units:
 
  a) Coastal G.A.F. Group 406 Brest, which is tactically subordinate to Group Command West.  Their long-range a/c type BV 138 are however grounded for about 2 months because of technical defects.
  b) KG 40 Bordeaux - in no way dependent.  Cooperation by personal agreement.  Type FW 200.  At the present generally only one a/c out by day.
  c) Luftflotte 5 flies reconnaissance of a certain area on special request in each case.  So far only carried out once.  Recently requested again but refused because of lack of forces.
     
15.12.
  Nothing to report.
     
     
                                    (Signed):  DÖNITZ
     
     
     
  
  
 
                   
     
 
 
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