Convoy ON 127
|Convoy ON 127|
|Part of Battle of the Atlantic|
| United Kingdom
|Commanders and leaders|
|RADM Sir E O Cochrane KBE
LCDR A.H. "Dobby" Dobson RCNR
|Admiral Karl Dönitz|
|Casualties and losses|
|6 freighters sunk (44,113GRT)
1 destroyer sunk
Convoy ON-127 was a trade convoy of merchant ships during the second World War. It was the 127th of the numbered series of ON convoys Outbound from the British Isles to North America and the only North Atlantic trade convoy of 1942 or 1943 where all U-boats deployed against the convoy launched torpedoes. The ships departed Liverpool on 4 September 1942 and were met at noon on 5 September by the Royal Canadian Navy Mid-Ocean Escort Force Group C-4 consisting of the Canadian River class destroyer Ottawa and the Town class destroyer St. Croix with the Flower class corvettes Amherst, Arvida, Sherbrooke, and Celandine. St. Croixs commanding officer, acting Lieutenant Commander A. H. "Dobby" Dobson RCNR, was the senior officer of the escort group. The Canadian ships carried type 286 meter-wavelength radar but none of their sets were operational. Celandine carried Type 271 centimeter-wavelength radar. None of the ships carried HF/DF high-frequency direction finding sets.
As western Atlantic coastal convoys brought an end to the second happy time, Admiral Karl Dönitz, the Befehlshaber der U-Boote (BdU) or commander in chief of U-Boats, shifted focus to the mid-Atlantic to avoid aircraft patrols. Although convoy routing was less predictable in the mid-ocean, Dönitz anticipated that the increased numbers of U-boats being produced would be able to effectively search the area with the advantage of intelligence gained through B-Dienst decryption of British Naval Cypher Number 3. However, only 20 percent of the 180 trans-Atlantic convoys sailing from the end of July 1942 until the end of April 1943 lost ships to U-boat attack.
Initial contact 
Wolf pack Vorwarts was forming about 500 miles west of Ireland as the convoy left Liverpool. U-91, U-92, U-96, U-211, U-218, U-380, U-404, U-407, U-411, U-584, U-594, U-608, and U-659 formed a search line across the convoy's path just beyond the range of land-based aircraft. U-584 reported the convoy on 9 September, but lost contact that evening.
10 September 
U-96 regained contact on 10 September and torpedoed the Norwegian tanker Svene, the tanker F.J.Wolfe and the Belgian freighter Elisabeth van Belgie in a single submerged daylight attack. Sherbrooke fell back to aid the torpedoed ships while St. Croix, Ottawa, and Celandine searched unsuccessfully for U-96. F.J.Wolfe was able to regain its station with the convoy. Ottawa continued to patrol astern of the convoy after St. Croix and Celandine resumed their normal patrol stations.
A coordinated night attack on the convoy began with U-659 torpedoing the British tanker Empire Oil on the evening of 10 September. St. Croix made SONAR contact immediately prior to the attack and Celandine, Ottawa, and St. Croix searched for U-659 after the attack. St. Croix and Ottawa fell back to rescue 23 of the stricken tanker's crew of 41. U-404 torpedoed the tanker Marit II, U-608 launched torpedoes which missed the convoy, U-218 torpedoed the tanker Fjordaas, and U-92 and U-594 launched torpedoes which missed the convoy before Ottawa, St. Croix, and Celandine rejoined the convoy. Sherbrooke remained astern of the convoy aiding the ships torpedoed by U-96, and rescued all but one of the crew of the sinking Svene and Elisabeth van Belgie. The remaining escorts counter-attacked, and depth charge damage forced U-659 and U-218 to return to port. Both Marit II and Fjordaas were able to regain their stations in the convoy. Empire Oil was later sunk astern of the convoy by U-584.
11 September 
None of the escorts' RADAR sets were functional on 11 September. U-584 torpedoed the Norwegian Hindanger in a submerged daylight attack while St. Croix investigated a visual sighting six miles distant. Amherst fell back and rescued all but one of Hindanger's crew. A B-24 Liberator patrol bomber of No. 120 Squadron RAF prevented further daylight attacks on 11 September but U-96 sank a 415-ton Portuguese sailing trawler by gunfire in the vicinity of the convoy. In coordinated night attacks, U-380 missed with a salvo of four torpedoes, U-211 torpedoed the British whale factory ship Hektoria and freighter Empire Moonbeam, U-92 missed Ottawa with four torpedoes and U-404 torpedoed the tanker Daghild before Amherst and Sherbrooke rejoined the convoy. Daghild maintained station in the convoy and Arvida rescued all but four of the 140 crewmen from Hektoria and Empire Moonbeam before those ships were sunk astern of the convoy by U-608.
Parting shots 
Excellent visibility on 12 September allowed a close forward screen of four escorts to discourage U-boats sighted up to 7 miles away. U-407 and U-594 launched torpedoes unsuccessfully that night. U-594 sank the straggling Stone Street as the convoy came within range of Canadian Canso patrol bombers from Botland, Newfoundland on 13 September. The escort was reinforced at dusk by the Town class destroyer HMCS Annapolis and the V and W class destroyer HMS Witch from the Newfoundland-based Western Local Escort Force (WLEF). Both U-91 and U-411 launched torpedoes unsuccessfully while U-91 torpedoed the Canadian River class destroyer Ottawa in the pre-dawn hours of 14 September. Ottawa sank with 114 of its crew. The remainder of the convoy reached New York City on 20 September 1942.
Ships in convoy 
|Athelduchess (1929)||8,940 gross register tons (GRT)||destination New York City; carried convoy commodore RADM Sir E O Cochrane KBE|
|Bayano (1917)||6,815 GRT||destination Halifax|
|Bohemian Club (1921)||6,906 GRT|
|Boston City (1920)||2,870 GRT||china clay & mail||veteran of convoy SC 94; destination New York City; survived this convoy, convoy SC 104 & convoy SC 122|
|British Endurance (1936)||8,406 GRT||destination New York City|
|British Tradition (1942)||8,443 GRT||destination New York City|
|Clausina (1938)||8,083 GRT||destination New York City|
|Daghild (1927)||9,272 GRT||torpedoed, but survived to be sunk 5 months later in convoy SC 118|
|Domby (1932)||5,582 GRT||destination New York City|
|Egda (1939)||10,050 GRT||veteran of convoy HX 79; destination New York City|
|El Mirlo (1930)||8,092 GRT||destination New York City|
|Elisabeth van Belgie (1909)||1||4,241 GRT||(in ballast)||sunk by U-96 10 Sept|
|Empire Lytton (1942)||9,807 GRT||reached New York City and was sunk 4 months later in Convoy TM 1|
|Empire Moonbeam (1941)||3||6,849 GRT||(in ballast)||veteran of convoy SC 94; sunk by U-211 & U-608 12 Sept|
|Empire Oil (1941)||18||8,029 GRT||(in ballast)||sunk by U-659 & U-584 11 Sept|
|Empire Sailor (1926)||6,140 GRT||general cargo||destination Halifax; carried convoy vice commodore Capt H J Woodward DSO RN|
|Empire Thackeray (1942)||2,865 GRT||destination Halifax|
|F J Wolfe (1932)||12,190 GRT||damaged by U-96 10 Sept; reached St. Johns, Newfoundland 16 Sept|
|Fjordaas (1931)||7,361 GRT||returned to Clyde; damaged by U-218 11 Sept|
|G C Brovig (1930)||9,718 GRT||destination New York City|
|Hektoria (1899)||1||13,797 GRT||(in ballast)||veteran of convoy ON 67; sunk by U-211 & U-608 12 Sept|
|Heranger (1930)||4,877 GRT||destination New York City|
|Hindanger (1929)||1||4,884 GRT||(in ballast)||sunk by U-584 11 Sept|
|Laurits Swenson (1930)||5,725 GRT||romped|
|Liberty Glo (1919)||4,979 GRT||destination Halifax|
|Marit II (1922)||7,417 GRT||damaged by U-404 11 Sept; reached St. Johns, Newfoundland|
|Modavia (1927)||4,858 GRT||destination Halifax|
|Montevideo (1928)||4,639 GRT||destination New York City; survived this convoy & convoy HX 228|
|Nanking (1924)||5,931 GRT||8 passengers||destination New York City|
|Pachesham (1920)||6,090 GRT||detached for St. Johns, Newfoundland 15 Sept|
|Pan-Georgia (1919)||8,197 GRT||destination New York City|
|Stone Street (1922)||6,131 GRT||detached with defects 12 Sept; sunk by U-594|
|Sveve (1930)||(none)||6,313 GRT||(in ballast)||sunk by U-96 10 Sept|
|Vardefjell (1940)||8,316 GRT||returned to Clyde with engine defects|
|Willemsplein (1910)||5,489 GRT||coal||veteran of convoy SC 94; destination Halifax|
- Milner 1985 p.159
- Rohwer&Hummelchen 1992 p.161
- Hague 2000 p.158
- Milner 1985 p.289
- Blair 1998 p.30
- Tarrant p.108
- Hague pp.132, 137-138, 161-162, 164, 181
- Milner 1985 p.160
- Hague 2000 p.161
- Milner 1985 pp.162
- Milner 1985 p.161
- Milner 1985 p.162
- Blair 1998 pp.30-31
- Blair 1998 p.31
- Milner 1985 pp.161
- Milner 1985 pp.160-161
- Milner 1985 pp.161-163
- Milner 1985 p.163
- "ON convoys". Andrew Hague Convoy Database. Retrieved 2011-05-26.
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- Hague, Arnold (2000). The Allied Convoy System 1939-1945. Naval Institute Press. ISBN 1-55750-019-3.
- Lenton, H.T. and Colledge, J.J. (1968). British and Dominion Warships of World War Two. Doubleday and Company.
- Milner, Marc (1985). North Atlantic Run. Naval Institute Press. ISBN 0-87021-450-0.
- Rohwer, J. and Hummelchen, G. (1992). Chronology of the War at Sea 1939-1945. Naval Institute Press. ISBN 1-55750-105-X.
- Tarrant, V.E. (1989). The U-Boat Offensive 1914-1945. Arms and Armour. ISBN 1-85409-520-X.