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emason
23-07-2010, 20:28
The Strange Course of U-763

The U-763 was a type VIIC U-boat, commissioned on 13 March 1943 and fitted with a Schnorkel in April 1944. Her Commanding Officer was KapitanLeutnant Ernst Cordes.

5 July 1944
At about 18.00, U-763 attacked convoy ETC.26 (River Thames to France, Normandy invasion convoy) and was subsequently hunted for 30 hours by a hunter-killer group. The experience of U-763, between 6th and 9th July 1944, will probably remain unique in the history of the U-boat. The following is an extract from her log:

6 July
16.45. South of Isle of Wight. Bottomed again in 55 metres. Enemy still has contact. I shall wait here till night. Depth-charges are now fewer and further between. Thirty-four detonated in our near vicinity between 16.00 and 20.00. Despite the addition of oxygen and the use of potash cartridges, the air has become perceptibly fouler. A very great quantity of air was consumed by members of the crew who had to be moved in order to keep trim during my attempt to shift position. The crew are becoming more exhausted. It is nearly 30 hours since the boat was last ventilated. The first cases of vomiting occur, and I issue each man with a potash cartridge. Breathing becomes distressed. The enemy search group is still active overhead. The intervals between depth-charges are getting longer, but detonations are nearly all very close. During the 30 hours of the pursuit, 252 depth-charges were counted in the near vicinity, 61 at medium range and 51 at long range.

7 July
12.00. After having been pursued with asdic and depth-charges for nearly 30 hours, our greatest worry is the fixing of our position. No echo-soundings could be taken during that time and our alterations of course and the set of the tide have taken us a considerable distance. Dead reckoning puts us 20 to 30 miles north of Cherbourg.

16.54. Touched bottom (40 metres).

19.02. Bottomed in 40 metres. This shallow depth makes me wonder if we are actually further to the southward. There is a 9-knot current there. Though we are trimmed by the head, the boat is lying very badly. Rise to periscope depth. Course 330 degrees. Land in sight to port, bearing 300 degrees true.

22.58. It is beginning to grow dark. As visibility is bad to starboard, I can make no further check. There are no stars. From a study of the chart it appears certain that the current has carried us between the Channel Islands. Sounding continuously and utilising the northerly set, I try to schnorkel clear to the northward. Visibility ahead is good enough.

8 July
00.41. The soundings do not agree with the chart. An attempt to fix by radio beacon produces one position only (Brest), which passes through the area in question and, together with the soundings, appears to confirm our estimated position. So long as I have sufficient water and visibility there is no point in surfacing. Carry on schnorkelling in order to have the batteries sufficiently charged, by daylight, to enable me to obtain a fix at periscope depth.

03.37. Touched bottom (16 metres). Stopped schnorkelling. I determine to surface, since our estimated position cannot possibly be correct. The farther we proceed to the north-west the shallower the water becomes, whereas according to the chart it should become deeper. I wonder if the echo-sounder is reading correctly.

03.56. It is almost a flat calm, moonlight and misty. Surfaced. .. . About two and a half miles on the port quarter, four destroyers are lying in the moonlight. Land lies on both beams. The shapes of several steamships are visible to port. I turn off to the north-west, assuming that I have the enemy-occupied Cotentin Peninsula to starboard and the Channel Islands to port. The echo-sounder must be out of order and the current must have carried us into shallow water.

04.33. Submerge again when the echo-sounder shows 30 metres. Bottomed at 35 metres. After pondering over what I have seen, it suddenly occurs to me that we have fetched up close to the English coast. The direction of the Brest position line on the chart shows that in all probability we are at Spithead, however unlikely that may sound."

That night and the following forenoon U-763 remained bottomed a few miles north-west of the Nab light.

9 July
15.25. Left bottom.

15.48. Periscope depth at silent running speed. Using the periscope sparingly and just awash, I discern three small vessels anchored in the stream.

16.05. An anchored landing craft (US 264) lays on the starboard beam and ahead of her the hospital ship, No. 62. I pass between them to the other side where, on the port bow, I sight two old 2,000- to 3,000-ton steamers, in ballast, lying at anchor. On south-easterly courses the water becomes shallower. A fix by cross-bearings shows that I am in danger of being left high and dry by the tide. I therefore turn about and make for a 20-metre patch.

18.02. Bottomed again in 17 metres. Low water is at 22.04, so that I am no longer in danger of being stranded. We have inexplicably got the boat in here unnoticed and will get her out intact, for she must not fall into enemy hands.

Despite the opportunities that presented themselves, though there were no really worthwhile targets, Ernst Cordes could not attack for fear of his LUT torpedoes running ashore and falling into enemy hands.

22.20. Action stations. . . .

22.50. Leave bottom. Rise to periscope depth. I keep to the starboard side of the fairway. Returning landing craft and what I presume to be two destroyers pass us on the opposite course. . . .

23.38. Course 140 degrees. We have not been observed. The water gets gradually deeper.

From Ernst Cordes observations the possibility of penetrating into this area to lay mines was noted. Such an operation was planned, but it had to be dropped because of the subsequent U-boat evacuation of the Channel.

U-763 ended her career on 29 Jan 1945 by scuttling at Koeningsberg after receiving bomb damage from Soviet aircraft.

 

spruso
24-07-2010, 03:27
An interesting story - Very lucky to get out of that tangle. What is a LUT Torpedo?

Cheers
Bruce

emason
24-07-2010, 19:36
An interesting story - Very lucky to get out of that tangle. What is a LUT Torpedo?

Bruce, for you:

The LuT - Lagenunabhanger Torpedo (Bearing Independent Torpedo)

The German Torpedo Trials Staff had developed a special device for fitting to a number of torpedo types. This special device was a programmable guidance mechanism which guided the torpedo on a predetermined zig-zag course resembling a ladder. A torpedo fitted with such a device was called a LuT. (There was an earlier, simpler device called a FaT.)

Torpedoes of this type were called pattern running torpedoes, and were specifically designed to be used against convoys. (The British called them "Curlies")

The LuT could be fired by a submerged U-boat on any bearing from its target, meaning the U-boat did not have to be pointing at it from a beam angle.

When the torpedo left the tube it was steered automatically towards the target by a gyro setting. The distance of the LuT’s initial straight run to the target was automatically set by the U-boat’s echo ranging instrument while still in the firing tubes.

At the end of its initial run towards the target, it made its first turn either left or right as programmed. It then ran in a series of straight parallel lines 300 metres apart. Each leg would be either 800 or 1600 metres long as programmed. At the end of each leg it turned 180 degrees alternately left and right, running its pattern until it hit something or ran out of fuel.
 
From "The U-Boat War in the Atlantic":

"LuTs were fired in spreads of six, at five and fifteen-second intervals. The torpedoes opened out fanwise until their spread covered the extent of the convoy, when they began running in loops across its mean course, making good a slightly greater or lower speed, and in so doing covered the whole convoy.

In theory these torpedoes were certain of hitting every ship of from 60 to 100 metres in length; and the theoretical possibility of 95 to 99 per cent hits in an average convoy was, in fact, achieved on firing trails."

spruso
24-07-2010, 20:18
Thanks for that Bill. Sound like a pretty smart invention. I wonder how effective they were in actual use as compared to the normal torpedo.
Cheers
Bruce

Clio
30-07-2010, 17:21
If you read BdU Diary it is clear that U-boot control were equally bemused by Cordes experience.

However events like this led German staff officers (and commanders) to seriously underestimate the minefield defences of the Channel June 44-February 1945.

The Brazier, Buttermilk and Artizan fields proved particularly successful but the true extent of their success was only known in the post war era.

Cordes lost his life in the Channel soon after this extraordinary patrol ( U-1195).

dennis a feary
03-09-2010, 06:18
Further on U763 ;

U 763
Type: VII.C, ocean-going, schnorkel equipped (June, 1944), the first
U-B equipped with the Hohentwiel FuMo 61 active radar.
Constructor: Kriegsmarine Werft, Wilhelmshaven.
Armament: 14 Torpedoes, 1 x 88mm, 2 x 20mm.
Commissioned: 13.3.43. Operational: October, 1943.
Service Life: 22. Operational Life: 14. Patrols: 6.
Theatre: Atlantic. Sank 1 m/v (1,499 grt). Shot down Halifax of 502
Sqd. (Fg Off Culling-Mannix) on 5.2.44, and Liberator F/53 Sqd. (Flt
Lt D.A.Bell) on 5.7.44. On 5.7.44, made an unsuccessful attack on a
military convoy, and decided to make for Alderney, Channel Islands.
On 6.7.44 attacked by destroyers, off Selsey Bill, counting 252 DC's
over a period of 30 hours. On 7.7.44 the craft grounded at 120 feet,
continued on its way, and bottomed at 50 feet. U 763 was enclosed by
land on three sides, and Lt.Braun soon established that he had
grounded at Spithead, near Portsmouth. He spent the rest of the day
grounded, then stole away in the night. On 24.9.44 after detection
by radar and illumination by Leigh light, attacked by Liberator
A/224 Sqd. RAF Milltown (S.Ldr J.C.T. Downey) with DC's in position
61.00N 04.07W; U 763 was en route from La Pallice to Bergen, and was
damaged in the attack. Last Action: 24.1.45, 24.U-Flotille, bombed
in Konisgberg by USSR a/c.
Commanders: KL E. Cordes 03.43-08.44.
LT K. Braun 09.44-10.44. OL K-H. Schroter 11.44-01.45.
M/V attacked/damaged/sunk : Ringen(S), (Cordes).

Sadsac

dennis a feary
03-09-2010, 06:23
CLIO has `introduced' U1195, so here are details of the boat, and loss of Cordes ;

U 1195
Type: VII.C/41, ocean-going, schnorkel equipped (1945).
Constructor: F. Schichau, Danzig.
Armament: 14 Torpedoes, 1 x 88mm, 1 x 20mm.
Commissioned: 4.11.43. Operational: January, 1945.
Service Life: 17. Operational Life: 3. Patrols: 1.
Theatre: Atlantic. Sank 2 m/vs (18,596 grt). Departed: 24.2.45,
Bergen; for UK waters. Last Action: 6.4.45, 11.U-Flotille, sunk by
HMS Watchman (DD L.Cdr J.R. Clarke), around c/v VWP.16, in position
50.33N 00 55W, South of Portsmouth, UK.
The Commander was among those lost.
Commanders: OL K-H. Schröter 11.43-10.44. KL E. Cordes 11.44-04.45.
M/V attacked/damaged/sunk : James Eagan Layne(D), Cuba(S), (Cordes).

Sadac

chris westwood
03-09-2010, 08:09
what a great tale

perhaps cordes was alightly amiss about the intensity of the depth charting since hedgehogs only exploded on contact.

there's a real eeriness to the story.

Benbow
13-09-2010, 00:55
U1195 wreck video.

http://www.youtube.com/watch?v=EzqTotH5snI

Hunt for the conning tower hatch.

http://www.youtube.com/watch?v=CfG377qSs9k&feature=related

http://www.youtube.com/watch?v=EpqHhcogYE8&feature=related

Dive information and wreck details.

http://server2.web-mania.com/users/iantTayl/SSAC/DIVERP/23may04.pdf

Abbeywood.
27-10-2011, 07:05
Thanks to all respondents for confirming my story.
I have mentioned it to other people in my own local vicinity, - some doubted it while others pooh-poohed it as a figment of imagination.

After suffering 252 close proximity depth-charges it a wonder anything worked on U-763, let alone the echo-sounder.

As a point of interest when not in use the Schnorkelling tube was stowed in a recess in the deck. Was this allowed to flood when submerged or was there a valve fitted at the upper end to prevent flooding, if not, the tube would need to be drained before opening the induction valve inside the craft.
Also, can it be presumed that the main engines exhausted through the tube.

Thanks again for the confirmation and my regards to you all.
Pete'

Benbow
15-11-2011, 18:05
If I recall correctly (40 years can dull the memory some) ,we use to drain down the snort mast after it was raised prior to snorting in RN boats. I know on the Valiant/Churchill class I use to swing off the Emergency Flap valve to open it. Also the intermediate flood and drain valve comes to mind ?We would drain the mast and watch for the sight glass (tundish) to clear after draining prior to snort ventilating.