U-boat Archive - U-664 - Preliminary Report



	Op-16-Z

	SECRET 30 August, 1943


	PRELIMINARY REPORT ON THE INTERROGATION OF
	SURVIVORS FROM U-664, SUNK BY A/C FROM USS
	CARD ON 9 AUGUST, 1943.

	I. INTRODUCTORY REMARKS

	U-664, a 500-ton German U-boat, commanded by Oberleutnant zur See Adof GRAEF, of the 1936 Naval term was sunk by aircraft from USS CARD in position 40⁰12'N., 37⁰29'W., at 1509 GCT on 9 August, 1943. Three officers, including the C.O., and 41 men were rescued by USS BORIE, after seven hours in the water, and were transferred to the CARD the following day. The survivors were landed on 17 August at Casablanca, French Morocco, where preliminary interrogation was conducted.

	The ship's company of U-664 numbered 52 men. The abnormally large total compliment is explained by the fact that additional anti-aircraft armament was installed in U-664 prior to her last war cruise and three men specially trained in the operation and maintenance of these guns were drafted to the U-boat from coastal artillery units a few days before she left port. Moreover, Quartermaster HOLST was to be transferred after this patrol, and his relief, HOEFTMANN, was carried as a supernumerary for training purposes.

	During the morning of 8 August, U-664 had been surprised and attacked by aircraft from the CARD shortly after joining company with another 500-ton U-boat with which, according to survivors, it was intended to exchange supplies and fuel. The other U-boat, as yet unidentified, was the bombing target in this attack; before U-664 crash dived she was strafed by machine gun fire, which killed the Second Watch Officer, Leutnant z. S. BOEHME and Boatswain JENDELEIT. In the attacks which resulted in the sinking of U-664 on 9 August, 6 other members of the crew were killed by gunfire or were wounded and subsequently drowned. Of the 44 survivors, one officer and 8 men were hospitalized for wounds sustained in the action.

	U-664 is believed to have been commissioned in June, 1942, and to have made 5 war cruises, all but the last in North Atlantic waters. Total sinkings of 3 ships with aggregate tonnage of 18,000 tons were claimed for her. The crew were young but relatively experienced, most of the key personnel having been aboard since commissioning. A number of men, however, had left the U-boat for training as petty officers prior to her last patrol and had been replaced by young and altogether inexperienced recruits.

Although formally attached to the 9th U-boat Flotilla, based at Brest, U-664 put in at La Pallice after her second war cruise and at Lorient after her third. Survivors disclaimed knowledge of the reason for this irregular procedure.

Several reasons were advanced to explain why U-664 twice was surprised and successfully attacked by aircraft in spite of her recently installed heavy armament and Radar. It was stated that she had relied too strongly on the efficacy of her new armament. Survivors, other than officers, were comparatively insecure under interrogation.

II. DETAILS OF U-664.

Type:	VII C, 500 tons.
Building Yard:	Howaldtswerke, Hamburg.
Armament:
a) Guns:	(2) Model 34 machine guns (demountable) on bridge.
	(2) 20 mm. guns on widened platform abaft bridge.
	(4) 20 mm. guns on additional platform below, abaft and adjoining first gun platform. Quadruple mount, two over two, with curved splinter screen on either side, partially enclosing mount. Thickness of screen stated to be 10 mm. Guns capable of simultaneous or single fire. Mount manually (not power) operated.
	Forward deck gun (88 mm.) removed prior to last war cruise.
b) Torpedoes:	12 carried in boat; none in deck containers. Electric, air and "Curly" type torpedoes carried, exact number of each as yet undetermined.
c) Torpedo tubes:	Four forward, one aft.
d) Mines:	None carried.
Diesels:	G.W.
Electric Motors:	Siemens-Schuckert.
Radar:	Believed fitted immediately prior to U-664's last war cruise.
German Search Receiver: Fitted.
S.B.T.	Fitted.
Life Rafts:	Between 20 and 30 individual inflatable rubber boats (Einmann Schlauchboote), possible regulation German Air Force Equipment, were carried aboard U-664. These boats, made of thin processed rubber with rubberized fabric seam reinforcements, have yellow top and sides and black bottom. They are inflated by mouth or compressed air flask, and are large enough to accommodate one man in recumbent position. Approximately ten of these boats were put overboard at the time of the sinking.
Flotilla:	9th (Brest), under command of K.K. LEHMANN-WILLENBROCK.
Conning Tower Device: Blue Sawfish (Insignia of 9th U-boat Flotilla).
F.P.N.	M 42961
Patron Town:	(Patenstadt): Gaggenau (Baden), home of the Engineer Officer of U-664.

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	III. FIFTH AND LAST WAR CRUISE

	U-664 is believed to have left Brest on her fifth and last war cruise on Wednesday 21 July, 1943. It was stated that on Sunday, 18 July she had put to sea in company with another 500-ton U-boat, identified by several survivors as U-91, under the command of Oberleutnant z.S. HUNGERSHAUSEN (1936 Naval term). Both boats returned to port the following day, U-664 for minor adjustments to her outboard vents. She left again on 21 July, unaccompanied by any other U-boat, U-91 having remained behind for further repairs. The possibility of a slight mishap involving both boats was implied, but no further confirmation is at hand.

	Several aircraft were sighted in the Bay of Biscay, but U-664 was stated to have crash dived in each instance rather than engage the enemy with her new anti-aircraft armament.

	(NOTE: Reports of the striking force which sank U-664, based on information obtained from survivors and observations of heavy U-boat concentrations, indicated that U-664 proceeded directly from Brest to position 40⁰N., 40⁰W. where she awaited orders to enter a given operational area. Preliminary interrogation has failed to confirm this point.)

	U-664 cruised for 17 days without sighting any ships or sustaining any attacks. On the morning of 8 August, she rendezvoused with another 500-ton U-boat for the purpose of exchanging supplies. It was stated that U-664 was preparing to transfer fuel to the other U-boat when surprised by the CARD's aircraft. Both U-boats opened fire, U-664 utilizing her quadruple 20 mm. guns. After being heavily strafed and losing BOEHME and JENDELEIT, U-664 crash dived as the planes withdrew.

	(NOTE: The TBF involved in this attack received 20 mm. hits in her bomb bay. After U-664 crash dived the TBF attacked the other U-boat with bombs so successfully that a "kill" was claimed subsequently. The plane was shot down during her bombing run, and an F4F which assisted the TBF was lost.)

	Survivors stated that they had no knowledge of the destruction of either plane, nor had they determined the fate of the other U-boat.

	U-664 remained submerged for the remainder of the day, surfacing before dark. A ship was sighted and GREAF attacked at dusk, ordering two torpedoes fired. The first torpedo stuck in the tube and had to be ejected some minutes later by means of an explosive charge. The second torpedo fired but missed. Some of the survivors, knowing that the CARD had been in the vicinity at the time, stated under interrogation that the aircraft carrier was the projected target, but more evidence is attached to the statement of the Quartermaster, who was on watch during the attack. He denied categorically that the CARD had been attacked, stating that, although the target could not be identified positively, he and the officers believed it to have been a tanker.

	These were stated to have been the only torpedoes fired by U-664 on her last patrol.

	IV. SINKING OF U-664.

	At 1416 GCT on 9 August, U-664 was sighted on the surface in position

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	40⁰12'N., 37⁰29'W. by two TBF and one F4F aircraft on anti-submarine patrol from USS CARD. The day was fair, with broken cloud formations at high altitude, and the sea was calm. Survivors stated that the U-boat crash dived upon sighting the planes, making no effort to man her guns. In this connection, Seaman WOLF, charged with armament maintenance, stated that there had been insufficient time to reassemble the pieces. When the U-boat had barely reached periscope depth, survivors felt the shock of depth charges exploding close outboard. The lighting system failed, the electric motor switchboard was short circuited, fuses were blown and considerable minor damage was apparent through the boat. The electric motor switchboard was repaired quickly and the motors continued to function. For some reason, the U-boat resurfaced at once. All of the survivors were at a loss to explain this procedure, holding the unanimous opinion that the boat was still capable of diving and might have made good her escape had she tried to go deeper.

	(NOTE: Action reports of the attacking aircraft emphasize that one 500 lb. was dropped close aboard the port bow of the U-boat, followed some 10 seconds later by two depth charges from the second TBF, which seemed to "bracket the boat and lift it out of the water".)

	As U-664 surfaced fully and proceeded on her electric motors, the conning tower hatch was opened and several men, led by HOLST, came on the bridge to man the guns. They were immediately strafed by the F4F and all were either wounded or killed. The two radiomen, STENTEN and STUEBCHEN, then came on deck to aid the wounded and were injured themselves. At some time during the action the Engineer Officer, apparently believing that the U-boat had surfaced to surrender, called out to inquire of the Captain whether the men should begin to abandon ship. A number of men misinterpreted the question as an order and climbed out of the conning tower. GRAEF then decided to take the U-boat down again, and the men on deck found themselves in the water as U-664 submerged.

	(NOTE: A second 500 lb. bomb was dropped by the TBF 50-60 feet on the U-boat's port quarter as she started to dive.)

	U-664 submerged to a depth of 50 feet. Severe leaks had been sprung in the pressure hull, one in the radio room and one in the after compartments. The boat was filling rapidly and trim could not be maintained. The main lighting system was still out of order, and cracked battery cells were filling with water. The electric motors, however, were still functioning. After remaining submerged for about 10 minutes, GREAF ordered the tanks to be blown and the U-boat surfaced, down by the stern. The men now formally abandoned ship, many wearing life jackets and others taking rubber boats into the water. U-664 was observed to sink almost vertically, stern first, at 1509 GCT.

	Scuttling charges are not believed to have been set. Although it is possible that an efforts was made to send a radio message from U-664 reporting her sinking, damage to the radio equipment is believed to have precluded transmission.

	V. PREVIOUS HISTORY OF U-664.

	It is not not known when U-664 was laid down or launched. She is believed

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	to have been commissioned in mid-June, 1942, and was stated to have been attached to the 8th U-boat Flotilla, based at Danzig, during her Baltic trials, which were conducted in July and August, 1942. It was stated that U-663, preceding boat in the series and commanded by Klt. SCHMIDT, left the Howaldtswerke Yards at approximately the same time, and worked up with U-664 in the Baltic. Trials were run off without incident, and U-664 returned to Hamburg for overhaul at the Howaldtswerke early in September, 1942.

	(a) First War Cruise

	U-664 was stated to have left Kiel on her first war cruise at the end of October, 1942, unaccompanied by other U-boats. She put in briefly at the Norwegian port of Christiansand to complete with fuel and water, and proceeded to an operational area South of Iceland. While making the passage of the so called "Rosengarten", to enter the Atlantic between Iceland and the Faeroes, U-664 was attacked by a Sunderland flying boat and sustained damage to one of her diving tanks. This attack was stated to have occurred on 13 or 14 November, 1942, although it is possible that the attack took place some days earlier. The damage did not necessitate immediate return to port, but high seas prevailed throughout the patrol and U-664 put into Brest somewhat prematurely about 20 November, 1942. No torpedoes had been fired on this war cruise.

	(b) Second War Cruise

	U-664 left Brest on her second war cruise on or about 6 December, 1942, proceeding to an operational area in the North Atlantic. High seas again prevailed, but a 4500-ton tanker was torpedoed and claimed sunk. The U-boat was ordered to return to La Pallice rather than Brest, and was stated to have reached port about 12 January, 1943. The crew was quartered in La Rochelle.

	(c) Third War Cruise

	U-664 is believed to have left La Pallice in mid-February, 1943, proceeding again to the North Atlantic. During this cruise, she attacked two ships in convoy, firing torpedoes at night on the surface. It was claimed that both ships, freighters of 5000 tons and 8000 tons respectively, were torpedoed and sunk within a few minutes. During this patrol, U-664 was stated to have refueled from a 1600-ton supply U-boat, the identity of which has not been established. She was ordered to Lorient and entered port about 1 April, 1943. Survivors stated that life in Lorient was at a standstill and that the port was virtually a ruin. Men who were not granted leave were taken for a few days to a rest camp in the vicinity.

	(d) Fourth War Cruise

	U-664 left Lorient about 5 May, 1943, on her fourth war cruise. On 9 May, she was attacked by a Sunderland in the Bay of Biscay and seaman NAUTZ, smoking off watch on the bridge, received a machine gun wound in the knee. U-664 crash dived and escaped. No successes were obtained on this final North Atlantic patrol and no torpedoes are believed to have been fired. U-664 was stated to have remained at sea about six weeks and to have returned to Brest in mid-June, 1943. While in port, her 88 mm. forward deck gun was removed, her new anti-aircraft armament was installed, and Radar is believed to have been fitted.

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VI. NOTES

a) Other U-boats

	U-91	(See Chapter III)

	U-613	A diary entry records the departure of this U-boat from Brest on 6 March, 1943.

	U-659	A survivor from U-664 had made one war cruise on U-659, under Klt. STOCK (sunk in 43⁰32'N. 13⁰30'W. on 4 May, 1943 - 3 survivors). This was stated to have been U-659's second war cruise, in October and November, 1942. According to this survivor, 4 ships, totaling 27,000 tons, were sunk by U-659 on this patrol.

	U-663	(See Chapter V)

	U-TROJER	A survivor from U-664 had made 4 war cruises on the 500-ton U-boat commanded by Klt. TROJER (1936 Naval term), and stated that this boat had been attached to the 3rd U-boat Flotilla, based at La Pallice.

	U-?	The 500-ton U-boat which joined company with U-664 on 8 August, and which was probably sunk in the subsequent attack, was stated to have had as a conning tower device a black and white Ace of Diamonds.

b) Diesel-Electric Procedure

It was stated that U-664, contrary to the procedure adopted by certain other U-boats, cruised in the Atlantic at slow speed (6 knots) on both Diesels. It was not considered that cruising on Diesel-Electric was a more economical procedure.

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