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Notable events involving Usurper include:

The history of HMS P 56 / HMS Usurper as compiled on this page is extracted from the patrol reports and logbooks of this submarine. Corrections and details regarding information from the enemy's side (for instance the composition of convoys attacked) is kindly provided by Mr. Platon Alexiades, a naval researcher from Canada.

This page was last updated in December 2017.

14 Jan 1943
HMS P 56 (Lt. D.R.O. Mott, DSC, RN) shifted from her builders yard to South Shields. (1)

15 Jan 1943
HMS P 56 (Lt. D.R.O. Mott, DSC, RN) shifted from South Shields to Blyth. She was escorted by RML 548 (T/Lt. T. Wood, RNVR). (1)

19 Jan 1943
HMS P 56 (Lt. D.R.O. Mott, DSC, RN) conducted exercises off Blyth. (1)

21 Jan 1943
HMS P 56 (Lt. D.R.O. Mott, DSC, RN) conducted exercises off Blyth. (1)

24 Jan 1943
HMS P 56 (Lt. D.R.O. Mott, DSC, RN) conducted exercises off Blyth. (1)

26 Jan 1943
HMS P 56 (Lt. D.R.O. Mott, DSC, RN) conducted exercises off Blyth. (1)

28 Jan 1943
HMS P 56 (Lt. D.R.O. Mott, DSC, RN) departed Blyth for Holy Loch. She was escorted by HMS Preston North End (Lt. K.A. Vasey, MBE, RNR) until 0700/30 when HMS Bryony (T/Lt. T. Hand, RNR) took over the escort. (1)

1 Feb 1943
HMS P 56 (Lt. D.R.O. Mott, DSC, RN) arrived at Holy Loch to begin a training period. (2)

2 Feb 1943
HMS P 56 (Lt. D.R.O. Mott, DSC, RN) conducted exercises in Gare Loch. (2)

4 Feb 1943
HMS P 56 (Lt. D.R.O. Mott, DSC, RN) conducted exercises in Kilbrennan Sound. (2)

5 Feb 1943
HMS P 56 (Lt. D.R.O. Mott, DSC, RN) conducted exercises in Kilbrennan Sound. (2)

6 Feb 1943
HMS P 56 (Lt. D.R.O. Mott, DSC, RN) conducted full speed trials on the measured mile in Loch Long. (2)

7 Feb 1943
HMS P 56 (Lt. D.R.O. Mott, DSC, RN) conducted exercises in Loch Goil. (2)

9 Feb 1943
HMS P 56 (Lt. D.R.O. Mott, DSC, RN) shifted from Holy Loch to Arrochar. (2)

10 Feb 1943
HMS P 56 (Lt. D.R.O. Mott, DSC, RN) conducted torpedo firing trials off Arrochar. (2)

11 Feb 1943
HMS P 56 (Lt. D.R.O. Mott, DSC, RN) conducted torpedo firing trials off Arrochar. (2)

12 Feb 1943
HMS P 56 (Lt. D.R.O. Mott, DSC, RN) conducted torpedo firing trials off Arrochar. (2)

17 Feb 1943
HMS Usurper (Lt. D.R.O. Mott, DSC, RN) conducted attack exercises in Bute Sound with HMS Breda (Capt.(Retd.) A.E. Johnston, RN) as the target and HNoMS King Haakon VII as escort for HMS Breda. (2)

18 Feb 1943
HMS Usurper (Lt. D.R.O. Mott, DSC, RN) conducted attack exercises on Inmarnock Water with HMS Breda (Capt.(Retd.) A.E. Johnston, RN) as the target and HNoMS King Haakon VII as escort for HMS Breda.

In the evening attack exercises were carried out with HMS Satyr (Lt. J.P.H. Oakley, DSC, RN). (2)

19 Feb 1943
HMS Usurper (Lt. D.R.O. Mott, DSC, RN) conducted attack exercises on Inmarnock Water with HMS Breda (Capt.(Retd.) A.E. Johnston, RN) as the target and HNoMS King Haakon VII as escort for HMS Breda. (2)

25 Feb 1943
HMS Usurper (Lt. D.R.O. Mott, DSC, RN) was conducting exercises on Inmarnock Water when she was ordered to search in the Clyde area for her missing sister ship HMS Vandal (Lt. J.S. Bridger, RN).

The following submarines / ships were also ordered to search for HMS Vandal (which was not found until 1994); HMS Graph (Lt. P.B. Marriott, DSO, RN), HMS L 27 (Lt. W.N. Eade, RNR), HMS Severn (Lt.Cdr. A.N.G. Campbell, RN), HMS Stubborn (Lt. A.A. Duff, RN), HMS Whitehall (Cdr. C.L.de H. Bell, RD, RNR), HMS Breda (Capt.(Retd.) A.E. Johnston, RN), HMS Kingfisher (Lt.Cdr.(Retd.) G.H. Gandy, RN), HMS La Capricieuse (Lt.Cdr. G.W. Dobson, RNR), HMS Cygnet (Lt.Cdr.(Retd.) F.B. Proudfoot, RN), HMS Tedworth (Lt.Cdr.(Retd.) G.H. Warren, RN) and HrMs Jan van Gelder (Lt. P.L.M. van Geen, RNN). (2)

28 Feb 1943
HMS Usurper (Lt. D.R.O. Mott, DSC, RN) conducted attack exercises on Inmarnock Water with HMS Breda (Capt.(Retd.) A.E. Johnston, RN) as the target and HMS Skate (Lt. J. Smallwood, RN) as escort for HMS Breda. (2)

1 Mar 1943
HMS Usurper (Lt. D.R.O. Mott, DSC, RN) conducted S.T.U. (mine detction) trials off Fairlie on completion of which she proceeded to Brodick Bay. (3)

1 Mar 1943
Around 1830A/1, HMS Trespasser (Lt. R.M. Favell, RN) departed Holy Loch for Scapa Flow.

Around 2130A/1, she joined HMS Usurper (Lt. D.R.O. Mott, DSC, RN), which was also to proceed to Scpa Flow, and HMS Cutty Sark (Cdr.(Retd.) R.H. Mack, RN) coming from Brodick Bay which they had departed around 2100A/1. (4)

3 Mar 1943
HMS Usurper (Lt. D.R.O. Mott, DSC, RN) arrived at Scapa Flow where she was to participate in A/S exercises. (3)

6 Mar 1943
HMS Usurper (Lt. D.R.O. Mott, DSC, RN) conducted exercises off Scapa Flow. (3)

8 Mar 1943
HMS Usurper (Lt. D.R.O. Mott, DSC, RN) conducted exercises off Scapa Flow with HMS Trespasser (Lt. R.M. Favell, RN), HMS Offa (Capt. J. A. McCoy, DSO, RN) and HMS Middleton (Lt. C.S. Battersby, RN). (3)

8 Mar 1943
HMS Trespasser (Lt. R.M. Favell, RN) carried out exercises with HMS Usurper (Lt. D.R.O. Mott, DSC, RN), HMS Offa (Capt. J. A. McCoy, DSO, RN) and HMS Middleton (Lt. C.S. Battersby, RN). (4)

9 Mar 1943
HMS Usurper (Lt. D.R.O. Mott, DSC, RN) conducted A/S exercises off Scapa Flow with HMCS Athabascan (Cdr. G.R. Miles, DSO, OBE, RCN), HMS Rapid (Lt.Cdr. M.W. Tomkinson, DSC and Bar, RN), HMS Blankney (Cdr. P.F. Powlett DSO and Bar, DSC, RN) and HMS Brissenden (Lt. D.C. Beatty, RN). (3)

10 Mar 1943
HMS Usurper (Lt. D.R.O. Mott, DSC, RN) conducted A/S exercises off Scapa Flow with HMS Coll (T/Lt. E.V. Nash, RNR) and HMS Davy (Skr. W.J. Salisbury, RD, RNR). (3)

12 Mar 1943
HMS Usurper (Lt. D.R.O. Mott, DSC, RN) conducted A/S exercises off Scapa Flow with La Combattante (Lt.Cdr. A. Patou), HMS Brissenden (Lt. D.C. Beatty, RN) and HMS Echo (Lt. R.H.C. Wyld, RN). (3)

13 Mar 1943
HMS Usurper (Lt. D.R.O. Mott, DSC, RN) conducted A/S exercises off Scapa Flow with HMS Rapid (Lt.Cdr. M.W. Tomkinson, DSC and Bar, RN), HMS Echo (Lt. R.H.C. Wyld, RN) and HMS Brissenden (Lt. D.C. Beatty, RN). (3)

13 Mar 1943
Having completed her torpedo firing trials, HMS P 56 (Lt. D.R.O. Mott, DSC, RN) proceeded from Arrochar to Holy Loch. (2)

15 Mar 1943
HMS Usurper (Lt. D.R.O. Mott, DSC, RN) conducted A/S exercises off Scapa Flow with HMS Salamander (Lt. W.R. Muttram, RN), HMS Brissenden (Lt. D.C. Beatty, RN), HMS Offa (Capt. J. A. McCoy, DSO, RN) and HMS Obedient (Cdr. D.C. Kinloch, RN). (3)

16 Mar 1943
HMS Usurper (Lt. D.R.O. Mott, DSC, RN) conducted A/S exercises off Scapa Flow with HMS Fury (Lt.Cdr. C.H. Campbell, DSC and Bar, RN), HMS Brecon (Lt.Cdr. T.D. Herrick, DSC and Bar, RN), HMS Penn (Lt.Cdr. J.H. Swain, DSO, RN) and HMS Panther (Lt.Cdr. R.W. Jocelyn, RN). (3)

17 Mar 1943
HMS Usurper (Lt. D.R.O. Mott, DSC, RN) conducted A/S exercises off Scapa Flow with HMS Echo (Lt. R.H.C. Wyld, RN), HMS Brecon (Lt.Cdr. T.D. Herrick, DSC and Bar, RN) and two ML's. (3)

18 Mar 1943
HMS Usurper (Lt. D.R.O. Mott, DSC, RN) conducted A/S exercises off Scapa Flow with HMS Pathfinder (Cdr. E.A. Gibbs, DSO and 2 Bars, RN) and HMS Brissenden (Lt. D.C. Beatty, RN). (3)

19 Mar 1943
HMS Usurper (Lt. D.R.O. Mott, DSC, RN) conducted A/S exercises off Scapa Flow with HMS Intrepid (Cdr. C.A.de W. Kitcat, RN), HMS Middleton (Lt. C.S. Battersby, RN), HMS Pathfinder (Cdr. E.A. Gibbs, DSO and 2 Bars, RN) and HMS Penn (Lt.Cdr. J.H. Swain, DSO, RN). (3)

20 Mar 1943
HMS Usurper (Lt. D.R.O. Mott, DSC, RN) conducted exercises off Scapa Flow. (3)

22 Mar 1943
HMS Usurper (Lt. D.R.O. Mott, DSC, RN) conducted A/S exercises off Scapa Flow with HMCS Athabascan (Cdr. G.R. Miles, DSO, OBE, RCN), HMS Obdurate (Lt.Cdr. C.E.L. Sclater, DSO and Bar, RN), HMS Rapid (Lt.Cdr. M.W. Tomkinson, DSC and Bar, RN) and HMS Brissenden (Lt. D.C. Beatty, RN). (3)

23 Mar 1943
HMS Usurper (Lt. D.R.O. Mott, DSC, RN) conducted A/S exercises off Scapa Flow with HMS Middleton (Lt. C.S. Battersby, RN), HMS Salamander (Lt. W.R. Muttram, RN), HMS Halcyon (Lt.Cdr. C.H. Corbet-Singleton, RN) and HMS Panther (Lt.Cdr. R.W. Jocelyn, RN). (3)

24 Mar 1943
HMS Usurper (Lt. D.R.O. Mott, DSC, RN) conducted A/S exercises off Scapa Flow with HMS Obdurate (Lt.Cdr. C.E.L. Sclater, DSO and Bar, RN), HMS Eclipse (Lt.Cdr. E. Mack, DSO, DSC, RN), HMS Switha (T/Lt. L.H. Green, RNR) and HMS Bressay (T/Lt. J.E. Wilmot, RNVR). (3)

25 Mar 1943
HMS Usurper (Lt. D.R.O. Mott, DSC, RN) conducted A/S exercises off Scapa Flow with HMS Troubridge (Capt. C.L. Firth, MVO, RN) and two minesweepers. (3)

26 Mar 1943
HMS Usurper (Lt. D.R.O. Mott, DSC, RN) conducted A/S exercises off Scapa Flow with HMCS Athabascan (Cdr. G.R. Miles, DSO, OBE, RCN), HMS Pathfinder (Cdr. E.A. Gibbs, DSO and 2 Bars, RN), HMS Anthony (Lt.Cdr. John Henry Wallace, DSC, RN) and HMS Lewes (Lt.Cdr. M.V. Thorburn, DSC, RNVR). (3)

27 Mar 1943
HMS Usurper (Lt. D.R.O. Mott, DSC, RN) conducted A/S exercises off Scapa Flow with HMS Anthony (Lt.Cdr. John Henry Wallace, DSC, RN), HMS Troubridge (Capt. C.L. Firth, MVO, RN), HMS Lewes (Lt.Cdr. M.V. Thorburn, DSC, RNVR) and HMS Stevenstone (Lt. P.B.N. Lewis, DSC, RN). (3)

29 Mar 1943
HMS Usurper (Lt. D.R.O. Mott, DSC, RN) conducted A/S exercises off Scapa Flow with HMS Jamaica (Capt. J.L. Storey, DSO, RN), HMS Newcastle (Capt. P.B.R.W. William-Powlett, DSO, RN), HMS Stevenstone (Lt. P.B.N. Lewis, DSC, RN), HMCS Athabascan (Cdr. G.R. Miles, DSO, OBE, RCN) and HMS Brissenden (Lt. D.C. Beatty, RN). (3)

30 Mar 1943
HMS Usurper (Lt. D.R.O. Mott, DSC, RN) conducted A/S exercises off Scapa Flow with HMS Arrow (Lt.Cdr. W.W. Fitzroy, RN), HMS Troubridge (Capt. C.L. Firth, MVO, RN), HMS Lewes (Lt.Cdr. M.V. Thorburn, DSC, RNVR) and HMS Seagull (Lt.Cdr. C.H. Pollock, RN). (3)

4 Apr 1943
HMS Usurper (Lt. D.R.O. Mott, DSC, RN) departed Scapa Flow for Holy Loch. She was escorted by HMS Tadoussac (T/Lt. J.P. Davies, RNR). (5)

7 Apr 1943
HMS Usurper (Lt. D.R.O. Mott, DSC, RN) arrived at Holy Loch. (5)

12 Apr 1943
HMS Usurper (Lt. D.R.O. Mott, DSC, RN) was docked at Port Bannatyne. (5)

14 Apr 1943
HMS Usurper (Lt. D.R.O. Mott, DSC, RN) was undocked. She then proceeded to Holy Loch. (5)

21 Apr 1943
HMS Usurper (Lt. D.R.O. Mott, DSC, RN) and HMS Satyr (Lt. T.S. Weston, RN) departed Holy Loch for Lerwick. They were escorted by HMS Kingston Beryl (T/Lt. T.C. Kidd, RNVR). (5)

23 Apr 1943
HMS Usurper (Lt. D.R.O. Mott, DSC, RN) arrived at Lerwick.

She departed later the same day for her 1st war patrol. She was ordered to perform an anti-uboat patrol in the Norwegian Sea.

For the daily and attack positions of HMS Usurper during this patrol see the map below. [no positions are noted in the log of HMS Usurper for 8 and 9 May 1943 therefore no positions can de displayed on the map of the return passage back to Lerwick.]

(6)

28 Apr 1943
HMS Usurper (Lt. D.R.O. Mott, DSC, RN) makes a torpedo attack on the German U-boat U-467 in the Norwegian Sea. The target was not hit.

(All times are zone -2)
1820 hours - Heard well-defined HE. Went to periscope depth from 30 feet.

1825 hours - In position 62°11'N, 02°11'E saw the conning tower of a u-boat that was proceeding on the surface. The u-boat was painted white and was difficult to see. Two figures were seen on the bridge in dark blue or black clothes it was because of these two figures that the u-boat was sighted. Started attack. Enemy course 164°, speed 10.5 knots.

1837 hours - Fired two torpedoes from 3500 yards. Missed. Usurper lost trim when firing the torpedoes. The two remaining torpedoes of the intended salvo of four were not fired. Set up another attack.

1844 hours - Fired two more torpedoes.

1846 hours - The enemy turned stern on after having sighted the torpedoes. So these torpedoes also missed.

1850 hours - Went to 60 feet to reload the torpedo tubes. (7)

9 May 1943
HMS Usurper (Lt. D.R.O. Mott, DSC, RN) ended her 1st war patrol at Lerwick. (7)

12 May 1943
HMS Usurper (Lt. D.R.O. Mott, DSC, RN), USS Barb (Lt.Cdr. N. Lucker, Jr., USN) and USS Blackfish (Lt.Cdr. J.F. Davidson, USN) departed Lerwick for Holy Loch. They were escorted by HMS La Capricieuse (Lt.Cdr. G.W. Dobson, RNR).

14 May 1943
HMS Usurper (Lt. D.R.O. Mott, DSC, RN) arrived at Holy Loch. (8)

20 May 1943
HMS Usurper (Lt. D.R.O. Mott, DSC, RN) was docked at Port Bannatyne. (8)

21 May 1943
HMS Usurper (Lt. D.R.O. Mott, DSC, RN) was undocked and then returned to Holy Loch. (8)

22 May 1943
HMS Usurper (Lt. D.R.O. Mott, DSC, RN) conducted noise trials at Loch Goil. (8)

25 May 1943
HMS Usurper (Lt. D.R.O. Mott, DSC, RN) conducted attack exercises in the Clyde area with HMS Breda (Capt.(Retd.) A.E. Johnston, RN). Also gunnery exercises were carried out on a target towed by HMS Jan van Gelder (Lt. P.D. O'Driscoll, RNR). (8)

28 May 1943
HMS Usurper (Lt. D.R.O. Mott, DSC, RN) shifted from Holy Loch to Campbeltown.

During the night of 28/29 May 1943 HMS Usurper conducted attack exercises off Campbeltown on HMS Altair (Lt.Cdr.(Retd.) W.R.T. Clements, RNR) and HMS Whitehall (Cdr. C.L.de H. Bell, RD, RNR). (8)

29 May 1943
HMS Usurper (Lt. D.R.O. Mott, DSC, RN) returned to Holy Loch. (8)

30 May 1943
HMS Usurper (Lt. D.R.O. Mott, DSC, RN) departed Holy Loch for Campbeltown to participate in exercises.

These exercises were cancelled when HMS Untamed (Lt. G.M. Noll, RN) failed to surface. (8)

31 May 1943
HMS Usurper (Lt. D.R.O. Mott, DSC, RN) returned to Holy Loch.

Later the same day she again proceeded to Campbeltown. (8)

2 Jun 1943
During the night of 2/3 June 1943, HMS Usurper (Lt. D.R.O. Mott, DSC, RN), conducted pratice attacks off Campbeltown on HMS Wolfe (A/Capt.(Retd.) C.C. Flemming, RN) with four destroyers as escort. (9)

3 Jun 1943
HMS Usurper (Lt. D.R.O. Mott, DSC, RN) conducted exercises off Campbeltown with aircraft from HMS Indomitable (Capt. G. Grantham, CB, DSO, RN, flying the flag of Rear-Admiral C. Moody, RN). (9)

4 Jun 1943
HMS Usurper (Lt. D.R.O. Mott, DSC, RN) conducted exercises in the Clyde area. These included practice attacks on / with HMS Surf (Lt. D. Lambert, DSC, RN).

Also gunnery exercises were carried out on a target towed by HMS Blade (T/A/Lt.Cdr. S.T. Wenlock, RNR). (9)

8 Jun 1943
For the daily positions of HMS Usurper during the passage from Holy Loch to Gibraltar see the map below.

(9)

8 Jun 1943
HMS Usurper (Lt. D.R.O. Mott, DSC, RN) departed Holy Loch for passage to Gibraltar. She made the passage south through the Irish Sea together with HMS H 44 (Lt. R. Bannar-Martin, DSC, RN). They were escorted by HMS Saladin (Lt. A.A. Diggens, DSC, RN). (9)

11 Jun 1943
At 1300 hours, HMS Usurper (Lt. D.R.O. Mott, DSC, RN) parted company with HMS H 44 (Lt. R. Bannar-Martin, DSC, RN) and HMS Saladin (Lt. A.A. Diggens, DSC, RN). The passage south through the Irish Sea had been delayed for 14 hours due to fog and engine failure in H 44. (9)

24 Jun 1943
HMS Usurper (Lt. D.R.O. Mott, DSC, RN) arrived at Gibraltar. (9)

1 Jul 1943
HMS Usurper (Lt. D.R.O. Mott, DSC, RN) conducted A/S exercises off Gibraltar with HMS Troubridge (Capt. C.L. Firth, MVO, RN). (10)

5 Jul 1943
HMS Usurper (Lt. D.R.O. Mott, DSC, RN) departed Gibraltar for Algiers. Before proceeding she conducted A/S exercises off Gibraltar with HMS Antelope (Lt.Cdr. E.N. Sinclair, RN). (10)

5 Jul 1943
For the daily positions of HMS Usurper during the passage from Gibraltar to Algiers see the map below.

(10)

11 Jul 1943
HMS Usurper (Lt. D.R.O. Mott, DSC, RN) arrived at Algiers. (10)

18 Jul 1943
HMS Usurper (Lt. D.R.O. Mott, DSC, RN) departed Algiers for her 2nd war patrol (1st in the Mediterranean). She was ordered to patrol to the west of Corsica.

For the daily and attack positions of HMS Usurper during this patrol see the map below.

(11)

27 Jul 1943
HMS Usurper (Lt. D.R.O. Mott, DSC, RN) torpedoed and sank the French Château Yqem (2536 GRT, built 1925) about 6 nautical miles south-west of Ajaccio, Corsica, France in position 41°50'N, 08°37'E.

Château Yqem (in ballast) was in convoy with Cap Corse (2444 GRT, built 1929) escorted by the Italian torpedo boat Orsa (escort leader) and the German auxiliary submarine chaser UJ 2210. They were on passage from Ajaccio to Marseille. Château Yqem was hit astern by a torpedo and sank in five minutes. She had a crew of twenty-seven and two passengers and there were two victims (a crew member and a passenger). A second torpedo was observed to detonate on Sanguinari Island and Cap Corse (carrying 205 passengers) turned back to Ajaccio. UJ 2210 run up the torpedo tracks and dropped depth charges and believed the submarine was sunk. To make sure, the two escort vessels independently hunted the submarine throughout the night. At 1907 hours, Orsa got an echo but then lost it. At 1925 hours contact was regained and Orsa dropped twice four depth charges and this was followed by two more and observed air bubbles. It was thought that perhaps two submarines had been present and some oil was observed but HMS Usurper had escaped. The next morning, two escort vessels returned to Ajaccio. VAS 237, VAS 238, VAS 239 and VAS 240 were also sailed to hunt the submarine but without result.

(All times are zone -2)
1645 hours - Sighted a convoy of two merchant vessels of 2500 tons escorted by a destroyer. Started attack.

1707 hours - Fired two torpedoes at the leading merchant vessel from 2400 yards. One hit was heard but could not be observed as Usurper had gone deep on firing.

1715 hours - Seven depth charges were dropped down the post side but they were not close and caused no damage to Usurper.

1735 hours - Three depth charges were dropped ahead.

1925 hours - The destroyer was in contact with Asdic.

1927 hours - Six depth charges were dropped close but again they caused no damage.

1944 hours - Five depth charges were dropped.

Usurper finally surfaced at 0028/28 and cleared the area at speed. (7)

28 Jul 1943
HMS Usurper (Lt. D.R.O. Mott, DSC, RN) attacked the French passenger vessel Cap Corse (2444 GRT, built 1929) west of the Gulf of Sagone, Corsica, France with four torpedoes. No hits were obtained.

Cap Corse She was to be escorted by the Italian torpedo boat Orsa and the German auxiliary submarine chaser UJ 2210 which had sailed two hours before to clear the area from submarines. The attack was unobserved and Orsa joined up with Cap Corse but UJ 2210 was ordered to remain behind and search for submarines the approaches of Ajaccio.

(All times are zone -2)
2005 hours - Returned to periscope depth after having made repairs to one of the periscope wires. Saw a liner of about 4000 tons at a range of about 8000 yards. Usurper was already past her beam but Lt. Mott decided to attack as this was a too valuable target to let by. Besides that she was unescorted.

2016 hours - In position 42°05'N, 08°29'E fired four torpedoes from 9000 yards. No hits were obtained. (7)

4 Aug 1943
HMS Usurper (Lt. D.R.O. Mott, DSC, RN) ended her 2nd war patrol (1st in the Mediterranean) at Algiers. While at Algiers Usurper developed a serious oil fuel leak into the W/T cabinet which resulted in the complete stripping down and rebuilt of the W/T cabinet. This kept Usurper out of action for quite some time. (7)

14 Aug 1943
HMS Usurper (Lt. D.R.O. Mott, DSC, RN) was docked at Algiers. (12)

18 Aug 1943
HMS Usurper (Lt. D.R.O. Mott, DSC, RN) was undocked. (12)

24 Sep 1943
HMS Usurper (Lt. D.R.O. Mott, DSC, RN) departed Algiers for her 3rd war patrol (2nd in the Mediterranean). She was ordered to patrol in the Gulf of Genoa. (12)

1 Oct 1943
At 0320 hours, the German auxiliary submarine chaser UJ 2209 reported that a submarine had attacked the German transport ship KT 19 in the Gulf of Genoa (Grid CJ 1691). They were en-route from Livorno to Bastia.

at 0320 hours, in poor visibility, the German transport KT 19 escorted by UJ 2209 reported missed by a torpedo in CJ 1691 (approx. 43°09'N, 09°46'E). While taking avoiding action both vessels collided and were damaged. If the attack was genuine then HMS Usurper (Lt. D.R.O. Mott, DSC, RN) could have been the author although just outside her zone area (zone SR). The poor visibility could have accounted for an error in position.

4 Oct 1943
At 0956 hours, the German auxiliary submarine chaser UJ 2208 obtained an echo and attacked it, dropping a total of sixty-nine depth charges in six runs, the last one at 1155 hours. The position was CJ 1345 (approx. 44°15'N, 09°06'E).

However, this is unlikely to have been HMS Usurper. The submarine was operating in zone SR (south of 43°25'N) until the previous evening and had just been ordered to zone SO and the position of UJ 2208 was about 3 miles outside of zone SO. Although not impossible, it is unlikely that the submarine would have crossed zones SP and SO at a fairly high speed to reach the position reported by the German submarine chaser. The submarine was aware the area had been heavily mined by the enemy and it was more likely that she would have moved cautiously.

UJ 2208 had been attacked the previous afternoon by HMS Sickle and her asdic operator had failed to pinpoint the submarine. On the 15th of the month, he would direct an attack on a bogus contact between Portofino and La Spezia. We can confirm the latter as UJ 2208 was observed from a distance by HMS Ultor It is therefore quite likely that the attack on 4 October was also on a bogus target.

It is more probable that HMS Usurper was victim of a mine.