U-BOAT ATTACKS ON CONVOY O.B.318 ON 7TH, 9TH and 10TH MAY, 1941.
     
 
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From. . . . . . . . . . THE CAPTAIN (D) GREENOCK, ALBERT HARBOUR, GREENOCK.
Date. . . . . . . . . . . 9th June, 1941.
To. . . . . . . . . . . . THE COMMANDER-IN-CHIEF, WESTERN APPROACHES.
  (Copies to:  The Director of Anti-Submarine Warfare,
                     The Captain (D) Liverpool.
                     The Captain (D) Londonderry.
                     The Senior Officer, 3rd Escort Group.)
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                  The following report on U-boat attacks on Convoy O.B.318 on the 7th, 9th and 10th May, 1941, is forwarded.  All times are Greenwich Mean Time.  
     
  Phase 1.  
     
          2.        At approximately 2100 on Wednesday 7th May, 1941, O.B. 318 consisting of 38 ships in nine columns was in position 610 29' N, 240 30' W steering 3180 at 8 knots.  
     
          3.        The sea was calm, sky clear, and visibility good.  It was daylight.  
     
          4.        The Escort were disposed in W.A.C.I. diagram XII (old issue) as follows:  
     
 
BULLDOG A. DIANTHUS Q.
AMAZON T. ROCHESTER F.
BROADWAY G. MARIGOLD R.
NASTURTIUM B. ANGLE O.
AURICULA D. PRIMROSE E.
 
     
                  DANEMAN was taking up a position between the rear ships of the two outer port columns, having just joined the convoy.  H.M.S. RANPURA was in position between the 4th and 5th columns.  
     
          5.        At 2058/7, H.M.S. BULLDOG obtained an asdic contact at 1000 yards.  The range closed rapidly, then contact was lost.  H.M.S. BULLDOG altered course to starboard and passed through the convoy between the 8th and 9th columns in an endeavor to regain contact.  
     
          6.        At 2115, S.S. EASTERN STAR was torpedoed followed 10 seconds later by S.S. IXION.  These were the rear ships of the 4th and 5th columns respectively, and they appeared to have been struck on their starboard sides.  White rockets were observed, but it is not clear which ship or ships fired them.  
 
          7.        On seeing the explosions, H.M.S. AMAZON, who had moved over to a position in the centre ahead of the convoy, turned to port and increased to 20 knots, passed down between the 3rd and 4th columns of the convoy, gaining asdic contact right ahead at 1700 yards at 2122/7.  
     
          8.        At the same time (2122/7) H.M.S. ROCHESTER having searched on the starboard quarter of the convoy, reported sighting a periscope in the direction of H.M.S. AMAZON'S contact.  
     
 
        9.        At 2138 H.M.S. BULLDOG obtained contact and with H.M.S. AMAZON and H.M.S. ROCHESTER, carried out a hunt in which some promising attacks were made.
 
     
 
 

Click this text to view a chart of Phase I

Note:  Ranpura was a 10,000-ton former liner serving as a merchant cruiser
Note: U-94 made this submerged night attack firing four torpedoes - the 10,300-ton British freighter Ixion and the 5,658-ton Norwegian freighter Eastern Star sank - U-94 escaped with heavy damage

 

 
 

   
- 2 -
     
  U-BOAT ATTACKS ON CONVOY O.B.318 ON 7TH, 9TH and 10TH MAY, 1941 continued  
     
          10.        The Commodore made an emergency turn to port at 2117/7.  
     
          11.        S.S. EASTERN STAR burned fiercely, but her whole crew were picked up by H.M.T. DANEMAN who proceeded to rejoin the convoy at 2230/7.  S.S. MAILSEA MANOR rescued survivors from S.S. IXION.  
     
          12.        Records from the 7th Group are not available, but it is believed that the remaining escorts stayed with the convoy, with the exception of H.M.S. BROADWAY who carried out a sweep on the port quarter of the convoy before being ordered to rejoin by H.M.S. BULLDOG at 2140/7.  H.M.S. MARIGOLD picked up survivors presumably from S.S. IXION, and was ordered to rejoin the convoy at 0300/8.  
     
          13.        The hunt (paragraph 9) continued until about 0015/8 when contact was finally lost.  H.M.S. ROCHESTER proceeded to rejoin the convoy, whilst H.M.S. BULLDOG and H.M.S. AMAZON carried out an extensive search.  At 0930/8 they too proceeded to rejoin.  
     
          14.        No attacks were made on the convoy on Thursday 8th May, 1941.  
     
          15.        At 1800/8 the corvettes of the 7th Group were detached to proceed to their next rendezvous, and on leaving the convoy, they carried out an extensive search astern.  
     
  PHASE II.  
     
          17.        By noon Friday 9th May 1941, the convoy was in position 610 35' N, 320 30' W steering 220 at 8 knots.  The visibility was good.  Wind W.S.W. force 4, Sea 3, Swell 2.  
     
          18.        The Escorts were disposed in accordance with a 3rd Group Escort diagram as follows:  
 
  (i)  In line abreast from left to right, H.M.SHIPS AMAZON, HOLLYHOCK, BULLDOG, NIGELLA, BROADWAY, 300 yards ahead of convoy and 200 yards apart.  
     
  (ii)  H.M.T. DANEMAN and H.M.S. AUBRETIA 1500 yards on the port and starboard beam of the convoy respectively.  
     
 
(iii)  H.M.T. ST. APOLLO 1500 yards in rear of the convoy.
 
 
 
  (iv)  H.M.T. ANGLE had been detached shortly before noon.  
     
          19.        At about 1201/0 S.S. ESMOND (No. 91) and S.S. BENGORE HEAD (No. 71) were torpedoes within a matter of seconds.  
     
          20.        The convoy made an emergency turn of 0400 to port, and this was followed by a further turn of 200 to port before 1230/9.  
     
          21.        H.M.S. had detected the hydrophone effect of torpedoes with her asdic and made an R/T report to the effect that the attack was from the starboard side.  At the same time, this ship altered course to starboard and a contact was obtained bearing 3350 1000 yards but was lost during the turn.  
     
          22.        H.M.S. BROADWAY, who had turned to port towards the torpedoed ships, counter-attacked a contact with one charge at 1203/9.  
     
          23.        At 1204/9 H.M.S. AUBRETIA sighted a periscope bearing 0000 800 yards moving from port to starboard.  A counter-attack was carried out with a 10 charge pattern at 1206/9.  Contact was not regained astern.  H.M.S. BULLDOG came across to join AUBRETIA and H.M.S. BROADWAY in the hunt.  
     
     

Click this text to view a chart of Phase II

Note: U-110 fired three torpedoes (the fourth was a misfire) and sank the 4,976-ton British freighter Esmond and the 2,609-ton British freighter Bengore Head in this attack

 

 
 

   
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  U-BOAT ATTACKS ON CONVOY O.B.318 ON 7TH, 9TH and 10TH MAY, 1941 continued  
     
          24.        At 1215/9 H.M.S. AUBRETIA obtained contact bearing 2360 1800 yards, and a 10 charge pattern was fired at 1223/9.  The depth charges put H.M.S. AUBRETIA'S asdic temporarily out of action, and she closed the boats of S.S. ESMOND to pick up survivors.  
     
          25.        H.M.S. BULLDOG and H.M.S. BROADWAY remained in contact after H.M.S. AUBRETIA'S last attack, and at about 1237/9, U-110 broke surface.  H.M.S. BROADWAY shaped course to ram, but fired two depth charges beneath the U-boat instead, set at 100 feet, in an endeavour to make the crew abandon ship before scuttling her.  In this encounter the U-boat's hydroplanes struck H.M.S. BROADWAY on the port side causing damage to oil fuel tanks and the port propeller.  After a short gun action the U-boat's crew abandoned ship, and were picked up at 1430/9 by H.M.S. AUBRETIA who had returned from S.S. ESMOND.  
     
          26.        H.M.S. BULLDOG proceed with "operation PRIMROSE" (which has been the subject of a separate report) whilst H.M.S. BROADWAY and H.M.S. AUBRETIA patrolled the area.  
     
          27.        When the convoy was attacked at 1201/9 H.M.S. AMAZON moved across to take up a position 5 cables ahead of the Commodore, having been ordered by H.M.S. BULLDOG to take charge ahead.  On learning the H.M.S. NIGELLA'S asdic was out of action (subject of a separate report) H.M.S. AMAZON stationed H.M.S. HOLLYHOCK ahead with H.M.S. NIGELLA to port, whilst H.M.S. AMAZON proceeded to sweep down the outside of the convoy's starboard column.  
     
          28.        At 1228/9 S.S. EMPIRE CLOUD (position 92) followed by a few seconds later by S.S. GREGALIA (position 72) were torpedoed.  H.M.S. AMAZON was at this time 2100 6 cables from S.S. EMPIRE CLOUD, and after dropping one depth charge, gained firm contact at a range of 500 yards.  A counter-attack was carried out at once, and a hunt commenced.  
     
          29.        At 1230/9 H.M.S. NIGELLA and H.M.T. ST. APOLLO who had picked up survivors from S.S. BERGORE HEAD were coming across to assist H.M.S. AMAZON who was short of depth charges.  This hunt proceeded with promising results but no definite evidence of destruction was obtained.  Between attacks H.M.S. NIGELLA rescued survivors from S.S. EMPIRE CLOUD.  
     
          30.        H.M.S. HOLLYHOCK and H.M.T. DANEMAN remained with the convoy throughout, taking up positions (b) and (c) in W.A.C.I. (old issue) diagram No. 2, and proceeded without incident for the remainder of the day.  
     
          31.        At about 1435/9 H.M.S. BROADWAY (see paragraph 26) obtained a contact which was hunted and attacked in company with H.M.S. AUBRETIA until 1550/9 when contact was finally lost.  These two ships then proceeded to screen and assist H.M.S. BULLDOG.  
     
          32.        At 1755/9 H.M. SHIPS AMAZON, NIGELLA and ST. APOLLO had lost contact (see paragraph 29).  H.M.S. AMAZON proceeded to sweep back towards S.S. EMPIRE CLOUD, leaving the other two ships to search.  H.M.S. AMAZON returned at 1830/9 when H.M.S. NIGELLA and H.M.T. ST. APOLLO transferred some of their survivors to her.  
 
          33.        Soon after 1900/9 H.M.S. AUBRETIA, who had been told by H.M.S. BULLDOG to rejoin, closed H.M.S. AMAZON and transferred 32 prisoners and 27 survivors.  H.M.S. NIGELLA and H.M.S. AUBERTIA then proceeded to rejoin the convoy.  
     
          34.        H.M.T. ST. APOLLO patrolled between S.S. EMPIRE CLOUD and the position of the last U-boat contact (see paragraph 32) until necessary to meet a homebound convoy.  
 
 
 
 

 

Note: U-201 torpedoed and sank the 5,802-ton-ton British freighter Gregalia and torpedoed the 5,969-ton British freighter Empire Cloud which was abandoned but later salvaged - the boat escaped

 

 
 

   
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  U-BOAT ATTACKS ON CONVOY O.B.318 ON 7TH, 9TH and 10TH MAY, 1941 continued  
     
  PHASE III.  
     
          35.        On the night of May 9/10th, 1941, the only escorts with the convoy were H.M.T. DANEMAN and H.M.S. HOLLYHOCK on the port and starboard bows respectively.  
     
          36.        A moderate westerly breeze was blowing, sea slight, low swell, cloudy but with clear visibility.  
     
          37.        At 0220/10, the convoy course was altered to 2200.  
     
          38.        At 0246/10 an explosion was heard in the rear of the convoy.  No rockets were seen.  This was S.S. AELYBRYN (position not known) who had been struck by a torpedo well aft on the starboard side.  
     
          39.        H.M.S. HOLLYHOCK intercepted a W/T report soon after this incident purporting to come from S.S. HERCULES.  It is presumed that this ship was reporting the attack on the S.S. AELYBRYN.  
     
          40.        H.M.S. HOLLYHOCK carried out a search on the quarters and in the rear of the convoy without result, ordering H.M.T. DANEMAN to pick up survivors.  In the morning H.M.S. HOLLYHOCK closed and stood by S.S. AELYBRYN and after boarding the wreck to examine the damage and obtain food for her survivors, H.M.T. DANEMAN proceeded to Iceland.  S.S. AELYBRYN had some survivors from S.S. GREGALIA (paragraph 28) on board when torpedoed.  
     
          41.        As soon as this attack developed, the convoy scattered by order of the Commodore.  
     
  REMARKS - 1st ATTACK  
 
          42.        It is noted that a U-boat made a first sighting report of a convoy, probably O.B.318 at 1537 on Wednesday 7th May, 1941.  The convoy was steering 2900 and it is suggested that a more drastic alteration of course should have been made to evade.  
     
          43.        A large number of non sub contacts had been encountered prior to this attack.  It seems probable that the attack was made from the rear or quarter, and that H.M.S. BULLDOG'S contact at 2058/7 (paragraph 5) was not the U-boat which attacked the convoy.  
     
          44.        Paragraph 15.  It was later learned that while this search was in progress, U.110 was actually shadowing the convoy from 15 miles on the starboard bow.  
     
  2nd ATTACK  
     
          45.        It is evident that at least three U-boats had concentrated on the convoy by noon on Friday 9th May, 1941, and it is most satisfactory that at least one of those was destroyed by the Escorts.  It is notable that in spite of the fact that this was a daylight attack, the U-boat pressed their attacks well home, and appeared to be capable of using very high submerged speed.  
     
          46.        U.110 had taken up a position aster of H.M.S. BROADWAY half an hour before the attack on the convoy commenced, and conformed with H.M.S. BROADWAY's zig-zags so as to keep in her wake.  The importance of stern lookouts is again emphasised.  
 
 
 
 

Click this text to view a chart of Phase III

Note: U-556 fired two torpedoes at two ships damaging the 4,986-ton British freighter Aelybryn whih managed to reach Reykjavik - after the convoy dispersed the boat sank the 4,861-ton British freighter Empire Caribou and the 5,086-tpn Belgian freighter Gand

 

 
 

   
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  U-BOAT ATTACKS ON CONVOY O.B.318 ON 7TH, 9TH and 10TH MAY, 1941 continued  
     
          47.        U.110 was in S.S/T communication with another U-Boat until H.M.S. AUBRETIA'S attack at 1206/9 when, as prisoner stated, this other U-boat "went dead".  
     
          48.        It is considered that H.M.S. AUBRETIA'S attacks at 1206/9 and 1223/9 were made on two separate U-Boats, the second of which (U.110) had torpedoed the S.S. ESMOND and S.S. BERGORE HEAD.  
     
          49.        Later evidence showed that the enemy had not expected to find the escort still with the convoy as far as 320 W.  
     
          50.        In this and the first attack on the convoy, R/T communication between Escorts was most satisfactory, and greatly assisted the Senior Officer 3rd Escort Group to conduct and keep in touch with operations.  
     
  3RD ATTACK  
     
          51.        This attack was presumably made by a U-Boat which had been shadowing the convoy since the afternoon of Friday 9th May, 1941.  There is little information available concerning the method of attack, but it seems likely that S.S. AELYBRYN was in the rear of the convoy, and possibly a straggler.  No other ships are known to have been torpedoed.  
     
     
                                                                                                    
                                                                                                   C A P T A I N