U-boat Archive - BDU KTB PG30261

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

Appendix 1 to B.d.U's War Log

1 - 31 March 1940

(Weseruebung)

Invasion of Denmark and Norway

PG30261

Appendix 1 to B.d.U.'s War Log

1 - 31 March 1940

S.O. Only

By hand of officer.

WESERUEBUNG

4.3

The following order concerning U-boats was received from Naval War Staff in Naval War Staff (1st Division)'s Operations S.O. only 226/40:

Further U-boat sailings are to be stopped. U-boats which have already sailed are not to operate off the Norwegian coast.

All Naval forces to be ready for operations as quickly as possible. No special degree of readiness.

U-boat Situation when this order was received:

In the Atlantic:

U 28, U 29, U 32 - carrying out minelaying operations on the south and west coasts of England.

U 38 - West of Ireland, war against merchant shipping.

In the North Sea:

U 7 NW of the declared area.

U 56 in the Bight. Both boats on their way to their operations areas off the Norwegian coast.

U 14 in her operations area at the northern approach to the Channel, war against merchant shipping.

U 52 central North Sea, on her way out to the Atlantic. On her first patrol.

Ready for operations: (Atlantic boats underlined):

5.3:		U 21, 24, 58, 59, 34, 43, 46, 47
6.3:		U 30
7.3:		U 9, U 51
8.3:		U 49
9.3:		U 22
13.3:		(uncertain) U 31, 44

The following measures were taken when the order was received:

U 7 held back in the position she had reached, until the situation becomes clear.

U 56, which was at most 12 hours out of Wilhelmshaven, recalled.

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		c)	U 14 left in her operations area. U 52 continuing on her passage.
		d)	The flotillas were ordered to make all boats ready for operations as quickly as possible, disregarding all previous intentions (discharge of U-boats to U-boat school, large-scale repairs) and to report completion dates.
		e)	The boats of the U-boat school received the same order.

5.3	B.d.U. took part in the conferences with Chief of Staff Naval War Staff in Berlin.
		Subject of conference:
		Preparations for the occupation of Norway and Denmark by the German Armed Forces.
		A)	Intention: Surprise, simultaneous landing of troops in Narvik, Trondheim, Bergen, Egersund, Kristiansand and Oslo. Troops to be transported to the first 4 places by Naval forces, to the last 2 by Naval forces and transports. Air-borne troops to be transported by air (T.N.: SIC)
		B)	Situation:
			a)	Norway is actually neutral, but her sympathies lie with the enemy powers rather than with Germany. Nevertheless, once a successful surprise landing has been made, no stiff resistance is expected.
			b)	A restricted area has been declared in Scotland northeast of the Caledonian Canal which appears to have some connection with the massing of troops in that area, and English surface forces are beginning to return to Scapa from the west coast. These and other indications make it appear possible that the enemy is preparing an attack on Norway to support Finland. This possibility must be reckoned with until our own plans have been carried out.
			c)	When the operation has succeeded, strong reaction from the enemy is expected. It may be directed against our own newly-captured bases, or towards securing bases of his own. In both cases it is assumed that he will try to cut off communications by sea between Norway and Germany.
		C)	Basic Outline of Execution: (insofar as it concerns B.d.U.):
			a)	Surprise is essential. No incidents violating Norway's territorial rights, or which could be interpreted as doing so, must occur until the time of execution. Military measures which could cause premature uneasiness in Norway are to be avoided.
			b)	The following steps are to be taken to screen our operation:
				1)	Operations to prevent the enemy obtaining bases which could be used for counter-action

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				2)	Screening against surprise attacks if the enemy should start a similar operation at the same time or shortly beforehand.
				3)	Early attack on the enemy's naval forces and transport ships, if he should start an action against Norway.
				4)	Extensive screening of our own shipping from enemy surface forces.
				5)	Screening our own surface forces, once they have entered inshore waters, against pursuing enemy forces.
			c)	Advantage to be taken of opportunities of attack which may arise in the course of enemy counter-operations.
		D)	The operation is to be carried out in 4 days. Preparations are to be completed by the 10th March. Delays must be expected until the codeword is given.

6.3	B.d.U.'s Situation review:
	B.d.U.'s part in the operation planned is very extensive.
	1)	It consists chiefly in protecting our own Naval forces and landing troops once they have penetrated into Norwegian territorial waters, taking the Norwegians by surprise. The geographic structure of the Norwegian coast makes it necessary to have a large number of boats for this. Narvik must be considered as particularly endangered as the position and importance of this place will make it appear valuable in the eyes of the enemy both from a strategic and an economic point of view, and defense against enemy counter-measures will be most difficult there.
	2)	This operation will be a great challenge to the enemy and our own surface forces will be moving beyond the Shetlands-Norway line, so that enemy operations in the direction of the Norwegian coast are to be expected, which should offer numerous opportunities of attack. The aim of such operations maybe:
		a)	Counterlandings by the enemy.
			These are to be expected: In the area of Westfjord - partly because of the importance of Narvik, partly because the remote situation will give the enemy the chance to make use of his superior sea power.
			In the area of the Shetlands-Norway narrows - in order to control those narrows and as a starting position for action against German troops.
		b)	Operations by Naval forces against the German-Norway sea route, aimed to cut off the German Naval forces taking part in the landing from home and to make supply through the North Sea impossible.
			Such operations may be expected to take place in the area Shetlands-Norway-western approach to Skagerrak.

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Conclusion for our boats:
To a.		It will not be possible to prevent landings by disposing boats in deep formation off the possible landing places, because such places and the approaches to them are too numerous and there are not enough boats. One would only run the risk of being in the wrong place or having too few forces. It is better to have groups of U-boats in the open sea area, within reach of the endangered positions, which can press on and cut off when the direction of the enemy advance is known. The disposition of these groups can be so chosen that they have some prospect of intercepting the approaching enemy.
To b.		Disposition of attacking groups in areas which the enemy is most likely to use for his operations.
To a and b.			Disposition of boats along the approach routes which the enemy is expected to take, as close as possible to his bases.

3)	The most likely bases for the enemy to use are:
	Scapa-Kirkwall in the first place. Invergorden, Cromarty and Rosyth in the second.
	In the present state of their defenses, only minelaying operations can be carried out against these bases.
	This is possible for all 3.
	i.e.: off the wide Firth near Kirkwall inside Moray Firth, at approach to the Firth of Forth.
	It would take so long however, that the boats in question would probably not be available for the operation proper. In view of the few boats available no minelaying can be considered sufficiently important and urgent as to warrant this.
4)	Preliminary decisions:
	I have therefore decided to keep all boats back. In addition, B.d.U.'s responsibilities require that all boats within reach be made ready, if necessary postponing the less important repairs and trials.
	Flotillas have been given orders accordingly. Boats in the Atlantic and on outward passage, U 38 and U 52, have been kept back in the positions they have reached. U 7 has been ordered to return.
	U 14 has been left in her operations area, but she is expected to return very soon in any case. Boats of the U-boat school have been ordered to proceed to Kiel and fit out. They have only a small radius of action and nothing much can be expected from the training which their commanding officers have had, but in these circumstances they should nevertheless be able to take part. U 64 and U 65, still on trials, have been ordered to speed up their operational readiness with every available means. Everything has thus been done to make use of all boats which are able to proceed. It is expected that the following will be able to take part in the operation.

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	12	Atlantic boats
	10	small operational boats
	6	school boats
Total	28	U-boats

There are also 3 further boats in view for case "GELB".

U 38 has been ordered to return to the sea area north of the Shetlands. Here she will be together with U 52. Both these boats can be operated from here in time in connection with the operation planned.

C-in-C Group West is in control of the whole operation west of the line Ryvingen-Hanstholm. He gives the following instructions in his Most Secret S.O. only 531/40 to B.d.U.:

To screen the ports occupied against penetration by enemy forces.

To attack and damage forces approaching from enemy ports or operational areas.

Before the undertaking starts:

To lay mines off the convoy and fuel bases in the Orkneys and Shetlands and attack and damage enemy naval forces and convoys in this area.

If possible, and if Supreme Command of the Navy approves, to ascertain what enemy traffic there is in the area Stadtlandet-North Shetlands, and to damage it and enemy naval forces.

My view of these 3 requirements is:

Points 1 and 2 cover the period after the operation has begun. U-boats can carry out these tasks within the framework of the whole operation.

Point 3 covers the period before the operation begins. The minelaying required has only direct connection with the operation planned in so far as it is directed against those enemy bases from which countermeasures may be expected which would endanger the execution of "Weseruebung" proper, i.e. the surprise landing. These are places at which enemy landing troops could be embarked or from which part of the English battle fleet and its accompanying escort forces might be expected to sail. In my opinion the minelaying does not cover the bases of patrol forces and other usable anchorages, which would only be resorted to possibly later in the operation.

The main aim must be to ensure the success of the landings. The situation after that will have to be considered as it develops. Minelays in places which are desirable in themselves and had already been planned (U 56 had already sailed with a load of mines, but was ordered back) must be abandoned in favor of the main aim. As regards minelaying operations against the main bases, I do not consider these

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opportune either, in view of the few boats available, for the reasons set out on 6.3 in the War Log Appendix 1 para 3. A boat which lays a few mines and is not available for the main operation has not the same value as a boat equipped with torpedoes for this operation.

The attack on enemy merchant shipping and convoy bases has no connection with the operation planned. It would mean splitting up the forces and would lead to the danger that boats would use up all their torpedoes and draw anti-S/M forces into an area in which their presence is undesirable for the operation.

Reconnaissance of enemy traffic between Stadlandet and the Shetlands would be only partly in the interests of the operation proper. There would be a danger that the boats used for this would be out of action for the actual operation as they would have to turn back when they had used their supplies if the final date should be postponed. At present there is no guarantee that this will not happen.

9.3

B.d.U.'s Operations Plan:

Preliminary considerations.

The following ports are to be screened:

Narvik	distance	roughly	1000	miles
Trondheim	"	"	750	"
Bergen	"	"	450	"
Stavanger	"	"	400	"
Egeroe	"	"	300	"

Narvik must be considered particularly important and particularly endangered.

Range and endurance of the different types of boats are limited as follows by supplies of fuel and provisions:

Boats of the U-boat school:

As far as the western approach to Skagerrak.

southwest Norway

Endurance in operations area 7-8 days.

Type Weddingen:

As far as 62⁰ N (Bergen)

Endurance in operations area about 18 days.

Atlantic boats:

Whole Norwegian coast.

Endurance off Narvik about 30 days.

This is assuming that there will be no opportunity to supply away from home. There is of course the chance that they may be able to supply in several ports after the operation has succeeded, but this cannot yet be taken for certain. That would be counting your chickens before they were hatched. So far the operation has not been carried out, the supply vessels have not yet reached their ports of destination unharmed. The number of torpedoes which they can carry

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		must be considered when determining the distance at which the boats can be used. The small boats only carry 4 or 5 torpedoes. They might use them all in a very short time. A long outward passage would be out of all proportion to their fighting power. Finally, their cruising speed would not permit them to go beyond the latitude of 63⁰ in 4 days. This time is very short even for the large boats to reach Narvik. It cannot be certain that it will suffice. If the boats are sent out before the codeword is given, they may use up their supplies too soon and not be able to remain in their positions for long enough after the operation has started. If any boats are sent out before time It must be the large ones.
2)	Operations Plan:
	I intend to carry out my task as follows:
	a)	To screen the landing places north of the latitude of 63⁰ by large boats, south of this by small boats.
		To form a concentration off Narvik by disposing 4 boats in deep formation. To cut off Trondheim with 2 boats in deep formation inside the approach.
		To close Bergen with 5 boats, 2 each in deep formation off both the main approaches, the 5th immediately off the harbor.
		To close Stavanger with 2 boats, of which one will lie immediately off the harbor approach, the the second outside the harbor entrance. The latter will patrol the Haugesund at the same time.
	b)	To form two attacking groups. The northern group will consist of 6 large boats and will be in waiting positions in the area northeast of the Shetlands, while the southern group, consisting of 3 small boats, will be held in readiness east of the Orkneys, along the supposed approach route of the enemy forces in the Shetlands-Norway area. Both groups will be disposed in such a way as to make quick operation in the Shetlands-Norway narrows possible, but they will also be sufficiently far away from the narrows that they can still operate with some prospect of success against enemy forces which may approach west of the Shetlands to the northeast or through the Fair Passage to the southeast.
	c)	A group of 2 boats will be disposed off Pentland Firth to cover the eastern approach to Scapa. I do not intend to dispose boats off other enemy jumping-off bases, as this would mean weakening other groups, which would have serious consequences. Also, boats off jumping-off harbors only have a chance to attack in the short time that enemy forces are entering or leaving. If these movements take place at night at high speed prospects of success are small. I think it more profitable to have boats in area in which the enemy will have to operate.
	d)	The distance at which the U-boat school boats can operate is very limited and the low standard of training of the crews has to be taken into consideration. 2 of them will

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			be in positions off Stavanger, which are likely to be less important than other inshore positions.1 boat will be west of the northern gap in the minefield planned in the Skagerrak. The remaining 3 boats will form an attacking group southwest of Norway against enemy forces which may penetrate as far as the central North Sea, and will at the same time cover the western approach to the Skagerrak. (the boat's approach passage will be short and they may reach their positions as much as 2 days before the others. They are to make use of this period to hunt the S/M's which have often been reported south of Norway and so reduce the S/M danger to our own surface forces. They will accordingly be allocated temporary operations areas which they are to leave when the landings start.
		e)	The following points must be remembered:
			1)	Boats must approach unnoticed and remain undetected until the day of the landings.
			2)	The entrances must be closed as quickly as possible after our own forces have passed.
			3)	Encounters between our own surface forces and U-boats must be avoided.
			4)	The approach of our own surface forces must be screened.
		f)	Our own forces are few by comparison with the enemy's superior sea power and it is necessary to concentrate exclusively on the landing and consciously abandon any chances of success which are not immediately connected with this main aim; therefore:
			1)	No splitting up against subsidiary targets.
			2)	No attacks on merchant ships and convoys.
			3)	Radio silence, except for signals which are of importance for this operation.
			4)	No waste of ammunition for purposes which do not serve to screen the operation or weaken operational enemy forces.
		g)	Details of execution have been set out for the U-boats in Operations Order "Hartmut".

10.3	The fitting-out of the boats is complete. Except for 4 U-boat school boats, which have been delayed by ice, all are in harbor ready for operations. U 38 and U 52 are at sea, close to their future operations areas.
	The code-word has not yet been given, for reasons unknown to B.d.U. The boats are at 12 hours readiness.

11.3	In Most Secret 287/40 I Op. Naval War Staff has ordered that the boats intended for Narvik and Trondheim are to sail at once and

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	patrol the respective approaches unnoticed in order to frustrate possible enemy intentions.4 other large boats are also to put to sea to patrol Bergen and Stavanger.
	They are to attack and report only if enemy warships or troop transports are encountered. U 30, 34, 46, 47, 49, 51 sailed (Narvik and Trondheim).
	U 38 and U 52 have been ordered to occupy the areas south of Utvaer and off the Kors Fjord. In agreement with the Naval War Staff, it was then decided that the 2 other boats should sail on 13.3 (because U 31 is unexpectedly out of action and U 43 has still to complete some small repairs). The 2 positions off Bergen and Skudesnes will be occupied by 2 Narvik boats for the present. They will be relieved by U 43 and U 44. Boats have been ordered to observe the 3 mile territorial waters limit.

12.3	Situation unchanged.

13.3	U 43 and U 44 sailed to relieve the 2 Narvik boats off Bergen and Skudesnes.

	Russia and Finland have made peace.

14.3	Decyphered messages show that unusually large number of English S/M's are stationed off the western approach to the Skagerrak. This may have some connection with imminent English operations.

	After the Russian-Finnish peace the situation seems to be even more obscure. With regard to the coming operation, there is no indication of a possible date and Naval War Staff does not think the word will be given before the 20th; I have therefore decided to send 8 small boats for a short operation against the English S/M's reported.
	For further details of the operation see F.O. U/B West's War Log.

	Preparations have been begun to transfer the U-boat school boats to the North Sea. Part of their task lies in attacking enemy S/M's anyhow, so that they too can be operated now without deviating from the general plan. For this also see F.O. U/B West's War Log.

15.3	The situation is still not clear and enemy operations are possible in the northern North Sea. It therefore seems wise to hold back some of the boats which are proceeding north. All the large boats have been ordered to proceed at 9 knots only.

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16.3	In resent circumstances 2 boats seem insufficient for the Narvik approach and it is desirable to have more boats in the northern North Sea. I have therefore decided to send 2 Narvik boats to take up waiting positions at approximately the latitude of 63⁰. (U 47, U 49). They can be moved quickly enough from here in any direction.

17.3	An apparently successful air attack on Scapa. Where there are at present 6 battleships and light naval forces. It is possible that:
		a)	Ships were damaged and will need dockyard repairs.
		b)	The English battle fleet will leave this anchorage, which is so exposed to air attack, especially if the air attacks are continued with vigor, as the G.A.F. intends.
	In view of this, Naval War Staff issued instructions that the large boats were to be re-disposed as directed by Group West, except for 2 boats off Narvik and 2 off Trondheim, at least 4 boats are to be off the north coast of Scotland to make use of the G.A.F.'s results. I think this is very promising, but only if: