In the fall of 1941 Hitler demanded that German U-boats be placed in the Mediterranean, in order to help protect the convoys carrying supplies for the German Africa corps which was advancing towards Egypt. A considerable amount of boats were released, and in the course of the latter part of the year several U-boats had successfully gotten through the straits of Gibraltar, making the passage of north/southbound Atlantic convoys more dangerous for the Allies. Additionally, German Focke-Wolfe bombers and reconnaissance aircraft were operating west of Gibraltar, sinking ships as well as directing the U-boats towards their goals.

Unfortunately, the A 1 form for HG 73 is not available to me, and none of the reports summarized on this page discuss the actual attacks on the convoy, but below is some information on the ships sunk (see also the external links provided below for more information).

The British Empire Stream, on a voyage from Huelva for Dundee with 3500 tons of potash, was sunk by U-124 on Sept. 25. She had a crew of 29, 2 stowaways and 4 gunners - 4 crew, 2 gunners and 2 stowaways were killed.

The Norwegian Varangberg, on a voyage from Melilla and Gibraltar for Belfast and Cardiff with 4100 tons of iron ore, was sunk by U-203 on Sept. 26 (German time - date given as Sept. 25 in Norwegian sources, as well as in "Lloyd's War Losses"). She had a crew of 26 and 1 passenger - 21 died, 6 survived - my page about Varangberg has more details, including a crew list.

The Commodore's ship, the British Avoceta, on a voyage from Lisbon for Liverpool with 469 tons of general cargo and mail, was sunk by U-203 on Sept. 26 (date given as Sept. 25 in "Lloyd's War Losses"). She had a crew of 65, 6 gunners and 88 passengers - 43 crew, 4 gunners and 76 passengers missing.

The British Cortes, on a voyage from Lisbon for Liverpool with potash, cork and other general cargo, was sunk by U-203 on Sept. 26. She had a crew of 31, 6 gunners and 6 passengers - there were no survivors.

The British Petrel, on a voyage from Oporto for Bristol with 130 tons of general cargo and 275 tons of cork, was sunk by U-124 on Sept. 26. She had a crew of 27, 3 gunners, 1 passenger - 19 crew and the 3 gunners died. Survivors were picked up by Lapwing, which was also sunk (not sure if this can be correct? According to Uboat.net's info, Lapwing was torpedoed just 2 mins after Petrel). 9 survivors landed at Toonpoint, County Galway on Oct 9.

The British Lapwing, voyaging from Lisbon to Glasgow with 750 tons of cork and pyrites, was sunk by U-124 on Sept. 26. She had a crew of 29 and 5 gunners - 21 crew and 3 gunners died (9 survivors landed at Toonpoint, County Galway on Oct 9).

The British Cervantes, on a voyage from Lisbon for Liverpool with 500 tons of potash and 400 tons of cork, was sunk by U-124 on Sept. 26. She had a crew of 31, 5 gunners and 4 passengers - 3 crew, 2 gunners and 3 passengers died. 3 survivors from Avoceta saved.

The Norwegian Siremalm, on a voyage from Almeria for Barrow (via Gibraltar), with 4000 tons of iron ore, was sunk by U-201 on Sept. 27 (or U-124?) - 27 died, there were no survivors. See my page about Siremalm for more details, including casualty list. (HMS Springbank was also torpedoed in the same attack - ref external link below).

The British Margareta, voyaging from Gibraltar for Glasgow with 400 tons general cargo, including scrap and cork, was also sunk by U-201 on Sept. 27. All 34 survived and were picked up by the escorting HMS Hibiscus.

Related external links:
HG - 73, 19th to 28th September 1941 - Describes the battle, with a list of ships sunk. By going to the page Allied Ships hit by U-boats and entering the name of each ship sunk in the search field, more info is available on each incident, as follows: The loss of Empire Stream | Varangberg | Avoceta | Cortes | Petrel | Lapwing | Cervantes | Siremalm | Margareta | Springbank

From the Commanding Officer, HMS Duncan
to The Captain (D), 13th Destroyer Flotilla, Gibraltar
dated Sept. 22-1941

All times are Zone minus 1

Sept 17-1941:
17:00 - Convoy in position 180° Carnero Point 5 miles.
Senior Officer of Escort: HMS Farndale.

Sept 18:
13:59 - Sighted Focke Wolfe.
14:15 - HMS Springbank launched fighter aircraft.
14:30 - The German aircraft jettisoned bombs astern of the convoy, but was driven off by fighter.

Sept 19:
10:30 - HMS Farndale and HMS Vimy carried out sweeps astern, while HMS Duncan carried out sweeps ahead.
13:35 - Duncan rejoined, stationed ahead.
14:00 - Focke Wolfe sighted, flying up and down the starboard side of the convoy, occasionally sweeping ahead and astern to port side and back to starboard, mostly outside the range of Duncan's and corvettes' guns. Springbank engaged, forcing the Focke Wolfe to operate at a greater distance. Arranged flank marking procedure to assist Springbank.
16:35 - Focke Wolfe retired to the northeast.
17:15 - Sighted smoke bearing 290°, and at
17:20 - Duncan detached to investigate.
18:35 - Stopped to investigate and board the Spanish El Condado, subsequently listed class "Y".
22:15 - Duncan rejoined the convoy, stationed on the starboard beam.

Sept 20:
10:00 - Duncan detached to northward in order to try to locate HMS Wild Swan.
16:00 - Completed search and set course to rejoin the convoy.
16:25 - Sighted Focke Wolfe approaching on the port bow, altering away as soon as gun trained had approached to 6000 yards.
16:30 - Closed convoy at speed to assist in A.A. protection.
17:30 - Rejoined the convoy; Focke Wolfe not shadowing.
20:15 - Vimy and Duncan carried out stern sweeps.

Sept 21:
04:00 - Duncan left the convoy and set course to comply with sailing orders from V.A.C.N.A. (2200A/16 - copy not available).

Sept 22:
11:10 - Sighted the Spanish fishing vessel Nuevo Amparo No. VF 5895 L3, painted white, resembling description of Segundo Enrique in V.A.C.N.A.'s 1155/21 (copy not available).
17:00 - Arrived Gibraltar.

HMS Wolverine's Report of Proceedings
dated Oct. 2-1941

Sept 26:
10:40 - Left Gladstone lock and proceeded at best speed to meet Convoy HG 73, passing south of Ireland.

Sept 27:
22:15 - What turned out to be the last attack on this convoy was seen in progress from starshell 40 miles distant. Course was altered to intercept on the assumption that the convoy was at half the distance.

Sept 28:
00:10 - Joined the convoy while reforming in position 50 09N 17W, escorted by HMS Fowey, Hibiscus, Periwinkle, Gentian, Stonecrop, Myosotis, Begonia, Larkspur and Jasmine, with the latter temporarily detached.
Daylight - It was arranged that Fowey should continue to act as Senior Officer. Wolverine, in the absence of friendly aircraft, made use of hight speed to put down possible shadowing U-boats, closing in when air attack threatened.
10:15 - A Focke Wolfe Condor was sighted. Using German plain language, attempts were made by 10" signal projector to tempt the aircarft from distances between 7 and 8 miles in to barrage range, resulting in the aircraft closing to within 4 miles on two occasions, before being "scared" by fire from corvettes. However, when 2 more Condors joined it, V/S, to which there had been no reply, ceased. This means of provoking action was thought justified as the aircraft was making continuous homing signals and reporting the convoy's course and speed.
Difficulty was experienced in passing a signal (1231A/28 - copy not available to the webmistress), and it was not known whether this was received, because of some apparent interference. When the shadowing aircraft left, W/T silence was preserved.
6 or 7 U-boats were reported to be near the convoy that night, but no attacks developed. It was believed that the presence of only 1 destroyer may have had a great effect (high speed sweep, combined with a dusk alteration), or that some D/F bearings of the Condors may have been mistaken for U-boats.
It was understood that "the behaviour of friendly aircraft is reported by Fowey".

Sept 30:
20:21 - When in 52 53N 04 58W, identities were exchanged with HMS Hastings, whose convoy (BB 82) was on a reciprocal course to HG 73. Their position made an alteration to port, essential for one or both the convoys and Wolverine had time to inform Hastings of her own intentions. The Vice Commodore (the Commodore's ship had been sunk by then) was then instructed to order an emergency turn, carried out successfully, "although his lights appeared to fuse as soon as switched on. To turn the convoy back to its course the signal was made on Wolverine's V.F. lights, which can be rapidly set to a Port or Starboard turn in an emergency by any of H.M. Ships equipped with them".

Signed by the Lieutenant Commander (signature illegible, possibly J. M. Rowland).

Related external link:
HG (& SL) Convoys - In chronological order.