The Bitter End, The U-boat War, 1943-1945
by John Barratt
On 31st May, a week after calling off the U-boat offensive in the North
Atlantic, Donitz reported on the situation to Hitler. After listing all the
current allied advantages, the head of the Kriegsmarine outlined the various
technological developments which he hoped would tilt the war once more in the
U-boat waffe's favour. Already being tested was the "Naxos" short-wave radar
detector. Improved acoustic and homing torpedoes were under development, as was
the "schnorkel" breathing apparatus which could be fitted to existing U-boats
so that they would no longer need to surface in order to recharge their
batteries. Further in the future, among Germany's promised array of "wonder
weapons", were the revolutionary new Type XXI and XXIII U-boats. In the more
immediate term, Donitz was hoping to counteract at least the growing Allied
threat from the air by fitting his U-boats with quadruple AA guns.
Even so, immediate prospects were grim, but both Hitler and Donitz were adamant
that that the U-boat war should continue in some form. On all fronts the war
was turning against Germany, and at least the U-boats could make a contribution
to the defence of the Reich by tying down Allied resources which might
otherwise be used elsewhere. Thinking in particular of the growing devastation
being inflicted upon German cities by Allied bombing, Donitz asked: "Could the
submariner stand aside as a spectator, saying there was nothing he could do or
would do, and telling the women and children they must put up with it? …A
continuation of the U-boat campaign would involve certain and deliberate
self-sacrifice. I finally came to the bitter conclusion that we had no option
but to fight on."
From June 1943 the U-boats faced the additional disadvantage that their
cryptologists could no longer break Royal Navy codes, whilst "Triton" or
"Shark" was decoded virtually without a break until December 1944. In September
Donitz attempted to renew the Atlantic campaign. But although his U-boats were
now equipped with the new short-wave radar detector and acoustic torpedoes, the
outcome was ignominious and costly failure. Convoys continued either to evade
the U-boats, or strong escorts beat off the attackers at a heavy cost to the
wolf-packs. Those U-boats, which, usually in groups, attempted to fight on the
surface with their improved AA defences against Allied aircraft, were generally
On 12th November, noting gloomily that "The enemy holds every trump card… knows
all our secrets and we know none of his", Donitz abandoned wolf-pack tactics in
the North Atlantic. For the next six months U-boat commanders would operate
individually on their own initiative, a tactic which could never be more than a
nuisance to Allied shipping in convoy. During this period, in all theatres, a
total of 107 Allied ships (600,000 tons) , only eight of them in convoy, would
be sunk, whilst 136 U-boats were lost- a, for the Germans, truly miserable
ratio of 0.78 merchant ships sunk for each U-boat destroyed.
From early 1944 all German intentions were focused on the imminent Allied
invasion of Europe. The U-boat force was still numerically impressive, with a
total of 449 submarines in commission. Of these, 287 were still undergoing
trials or crew training, and 162 were operational, with an average of 43 at sea
on any one day. But all were effectively obsolete, and increasingly viewed by
their crews as "iron coffins".
During the spring about 73 U-boats were deployed in the French Biscay ports or
the Norwegian bases to combat Allied invasion attempts. But when the Normandy
landings began in June, U-boat attempts to intervene proved to be another
costly failure. Their movements betrayed by "Ultra" intercepts and improved
detection equipment, subject to ferocious air attack and highly effective
surface hunters, the U-boats were chased, harried, and in many cases sunk.
Though they continued their heroic and sacrificial efforts in the English
Channel and North Sea well into the summer, the final balance sheet for the
U-boats' attempt to disrupt the Allied invasion provided further grim reading.
By the end of August, when the U-boat campaign was abandoned, they had sunk 21
Allied ships, including 5 warships, for a loss of 19 U-boats and 1000 officers
At the end of August, with the Biscay bases threatened by capture or siege, all
seaworthy U-boats there were withdrawn to Norway. From here they would mount
Germany's last forlorn attempt to disrupt Allied by shipping by operating in
British coastal waters. Here they would be able to make more effective use of
the "schnorkel", and thus be more difficult to detect. But even so, results
proved meagre, and operational effectiveness was reduced by lack of major
repair facilities in the Norwegian bases, which often forced U-boats to run the
gauntlet of Allied air power when returning to Germany for maintainance. The
most that could be said was that the loss ratio was slightly more favourable to
the Germans than it had been for some time. Between August 1944 and the end of
the year, 8 merchant ships, two warships and a tug were sunk for the loss of 8
U-boats, a ratio of 1.5. But such results were insignificant in the scale of
Even so, the U-boat command did not finally abandon hope. Its senior officers
attempted to gain comfort from the fact that the "schnorkel" and the new radar
search detector made U-boats less vulnerable to discovery. But this advantage
largely disappeared once they revealed their location by attempting an attack.
Another apparent advantage seemed to be presented to the Germans in December,
when a change in "Enigma" procedures once more prevented the Allies from
reading the U-boat codes, whilst a situation in which the majority of U-boats
were now operating singly meant that were far fewer radio signals to aid in
pinpointing submarines' locations.
However the Allies were devoting massive resources to the war against the
U-boat. During December 1944 they concentrated 426 escort vessels and 420 RAF
Coastal Command aircraft in home waters. The result was further disappointment
for the Kriegsmarine. In November they had sunk one escort carrier and six
merchant ships for the loss of seven U-boats; in December the exchange was
seven merchant ships for three U-boats.
Right up until the end of the war a few U-boats continued to operate in the
North Atlantic, including an ill-fated attempt to revive wolf-pack tactics off
the US coast. Results were meager; by the end of the war U-boats in the
Atlantic had sunk 11 merchant ships, one frigate and one minesweeper, whilst
three U-boats had been lost out of the 22 sent to operate in this area. At
least, however, they had managed to occupy the attentions of 17 escort groups.
The final months of the war saw no upturn in U-boat fortunes. They managed to
sink 63 merchant ships, but the ever-increasing Allied onslaught, particularly
from the air, accounted for 152 U-boats.
Only in the final days of the war did the first of the new types of U-boat
begin to become operational. A Type XXIII, U2336, had the distinction of
sinking the last two merchant ships of the war, on May 8th, when, unbeknown to
her commander, hostilities had actually ceased. The only Type XXI actually to
become operational, U2511, sailed from Bergen , and was off the Faroe Islands
when she received the signal to cease hostilities, and ended active operations
by making an undetected dummy attack on a Royal Navy cruiser. At the end of the
war, The Kriegsmarine still possessed 393 U-boats, of which 126 were
operational, and 43 at sea.
The U-boats at sea responded to the order to surrender in various ways. About
23 came into British ports to surrender, three to Canada and four to the USA.
Others returned home or scuttled themselves . Two eventually fetched up in the
River Plate in Argentina, creating almost certainly unfounded reports that they
had carried into hiding various high-ranking Nazis. About 154 U-boats were
surrendered intact in German or Norwegian naval bases, and 218, including 82
Type XXI and 29 Type XXIII, scuttled themselves rather than surrender.
Depending on the means of calculation, estimates of total U-boats lost from all
causes during the war vary between 777 and 821. There are similar variations in
estimates of the number of their victims. So far as the Battle of the Atlantic
proper is concerned, an accepted figure is 2603 merchant ships with the loss of
30,000 Allied seamen. The toll exacted on Donitz's U-boat crews rated with
those of Allied bomber crews as the highest in any branch of any armed services
in World War II. Of a total of 40,900 men who served in U-boats, 28,000, or
70%, were lost, including a son of Grand Admiral Donitz.
Churchill later wrote that the U-boat threat had been the only thing which had
really worried him during the war, but more recent studies tend to suggest that
Donitz never came within measurable distance of achieving victory in the Battle
of the Atlantic. The failure to build up an adequate U-boat force prior to the
outbreak of war was critical in this, as well as the enormous shipbuilding
capacity of the Allies following the entry of the US into the war. But,
certainly to those who fought and died in it, the Battle of the Atlantic was
one of the grimmest and most bitterly contested campaigns of World War II.
Copyright © 2002 John Barratt.
Written by John Barratt. If you have questions or comments on this article,
please contact John Barratt at:
About the author:
John Barratt has authored many books to include: Armada 1588, The
Battle of Marston Moor, The Civil War in South-West
England 1642-1646, and Cavalier Generals.
Published online: 12/15/2002.