'KM' (iii) was the designation of Allied convoys (together with a numerical and sometimes a literal suffix) plying the route from the UK to the Mediterranean and occasionally onward, and as such reciprocals of the 'MKF' fast and 'MKS' slow convoys (22 October 1942/30 May 1945).

The 'KM' convoys were of two types, namely the 'KMF' fast and 'KMS' slow convoys. The 55 convoys of the 'KMF' series initially carried troops and equipment to North Africa in support of 'Torch'. When the Mediterranean became accessible after the defeat of the Axis forces in North Africa, the destination was extended farther to Alexandria and Port Said, in the process replacing the WS series which had previously steamed via Capetown and Durban to reach Suez. The 'KMF' series ran from October 1942 until the end of the war. The first of these convoys was KMF.1 of 26 October/8 November 1942 with 40 merchant vessels and an eventual total of 36 escorts. The last was KMF.45 of 23/24 May 1945 that was a dispersal convoy with 14 merchant vessels, many of them carrying troops, and four escorts.

The Action off Cape Bougaroun (otherwise the Attack on Convoy KMF.25A) was a German air action against the KMF.25A convoy off the coast of Algeria. The convoy of US, British, Greek and Dutch ships was attacked on 6 November 1943 by 25 German land-based aircraft, which sank or damaged six Allied vessels for the loss of six of their own number. This was a German tactical victory, but the Allied warships of the escort managed to the rescue of more than 6,000 service men and civilians without further loss of life.

The KMF.25A convoy comprised 26 transport vessels escorted by 15 warships bound from Liverpool to Naples. The transport vessels were carrying about 28,000 US, British and Canadian troops, as well as a complement of nurses and a sizeable volume of supplies. Most if not all of the vessels were armed with small-calibre naval and anti-aircraft guns: the US and Dutch ships had armed guards aboard to man these weapons. The convoy was designated Task Group 60.2 and was under the command of a US naval officer, Captain Charles C. Hartman in the destroyer Mervine. Task Group 60.2 otherwise included the British light anti-aircraft cruiser Colombo, the US destroyers Davison, Parker, Laub, Beatty, Tillman and McLanahan and the Brtish escort destroyer Haydon and two other 'Hunt' lass vessels. There were also four destroyer escorts (two Greek and two US), the latter comprising Frederick C. Davis and Herbert C. Jones.

It was on 27 October 1943 that the KMF.25A convoy departed the UK for Egypt and ultimately Italy. After passing Gibraltar, the ships received British air support, but the quality of the air support varied as the squadrons were constantly rotated with others: each rotation left the convoy without support for several minutes each time a fresh squadron arrived. It was during one of these intervals that a force of nine German torpedo-bombers and 16 level bombers intercepted the convoy.

The convoy was steaming in columns, each of between seven and nine ships, from Mers el Kébir to Naples. Laub was alone and6 miles (9.6 km) ahead of the convoy to provide a radar screen. Melvine led the warships in a circular pattern round the three columns: Beatty and Tillman were astern of the convoy and Mervine was some 2,000 yards (1830 m) ahead of it. Just after sunset, at about 17.45, on 6 November the convoy was sailing in overcast weather, some 40 miles (65 km) from Philippeville, off Cape Bougaroun in French Algeria when Laub detected six Axis aircraft approaching from the north. Laub’s commander radioed the information to Hartman, who signalled the destroyers to make smoke and prepare for action. The thousands of soldiers and civilians were also ordered below decks with instructions to remain there until the threat was over. A moment later, Tillman detected an Axis warplane and opened fire at a range of 8,000 yards (7315 m), too far to be accurate but nonetheless warning the other nearby escorts.

The German warplanes included Heinkel He 111 machines carrying F5b torpedoes, Dornier Do 217 machines with Fritz-X missiles and Junkers Ju 88 machines armed with Henschel Hs 293 missiles. The German warplanes were operating as small groups and attacked at an altitude of about 1,000 ft (305 m) above sea level. The US ships sent identification friend or foe signals to the approaching aircraft, but when one of these was identified as German, Hartman was informed and ordered the escorts to open fire. As the German warplanes came within range, the escorts and the transports opened fire with a massive hail of machine gun, anti-aircraft and naval gunfire. Seconds later, the Germans began to launch their missiles and torpedoes.

The battle last less than 30 minutes. Beatty, commanded by Commander William Outerson, first observed machine gun fire at 18.03 and picked up five incoming warplanes followed by a bomb explosion at 18.04. At 18.05, she opened fire on two more incoming Ju 88 torpedo-bombers at a range of 16,000 yards (14630 m).

The main weight of the attack seemed to be directed at Tillman, which was not hit as her captain expertly steered his ship through the bombing. The first German warplane sighted by Tillman was a Dornier machine, which dropped a glide bomb about 1,000 yards (915 m) off the beam while under heavy fire from the destroyer’s main battery. Machine gun fire from Tillman struck the projectile when it was about 600 yards (550 m) from the ship, and the bomb dived steeply and crashed 150 yards (140 m) off the ship’s port side. The bomber was then struck and blown up by the fire of Tillman's 5-in (127-mm) guns while another bomb exploded 500 yards (455 m) off the starboard beam. Though Tillman was not hit, concussion damaged the destroyer’s fire-control radar and the after plating of her hull.

At 18.13, one of the German warplanes launched at torpedo from 500 yards (455 m) at Beatty, and 30 seconds later the torpedo struck the destroyer’s after engine room. The explosion blew a relatively small hole in Beatty, 11 men were killed, one died later of wounds and another was blown overboard along with a K-gun and a depth charge. The charge did not explode; one officer and six men were wounded. Beatty began slowly to settle. Damage control parties were immediately ordered to patch the torpedo hole and extinguish fires, while other men jettisoned weighty topside items, ammunition and even the tow cable. The flooding of the engine room meant that no power reached any of the ship’s electronics. One of the magazines also filled with water, and this left Beatty listing 12° to port. The destroyer remained afloat for more than hours before her crew abandoned ship at 19.00 and, with her keel damaged, the destroyer broke in half and sank at about 23.00. The wounded were transferred to Parker.

The 18,017-ton Monterey, a War Shipping Administration-allocated Matson ocean liner serving as a troopship and carrying 3,966 soldiers, was in the convoy under the command of Captain Elis R. Johanson and was defensively armed with 20-mm anti-aircraft cannon. One torpedo-bomber shaped to attack the ship but was shot down by the ship’s gunners before a torpedo could be dropped. The aeroplane began to lose altitude and as it passed over Monterey, striking and ripping away some radio equipment.

The 9,135-ton Santa Elena, a WSA-allocated Grace Line liner converted to a troopship under the command of Captain William C. Renaut, was carrying 1,848 Canadian soldiers and 101 nurses. The ship was hit twice and sank hours later at position while under tow into Philippeville harbour. Four members of the crew were killed and the US armed guard on board freed several men who were trapped below.

Two armed Dutch transport vessels were also struck. The 19,355-ton Marnix van St Aldegonde, with 2,924 troops on board, was heavily damaged but suffered no deaths; the ship survived long enough to make it to shore, where she grounded and sank within Philippeville’s outer harbour as her captain was trying to beach her. Thousands of soldiers, merchant seamen and regular navy sailors had to take to the water. The other damaged Dutch ship was the 14,155-ton Ruys, which lost one man killed but made it to port. Both of the transport vessels which were lost had not sustained severe damage, but nonetheless sustained sufficient damage to cause their loss.

The Germans dropped dozens of missiles and torpedoes but most of them failed to find other targets. At least four hits were made on the Allied convoy, which destroyed six aircraft in return, it being estimated that 10 German airmen were killed. The British and Greek ships sustained neither damage nor casualties. Colombo steamed ahead of the centre column of ships and provided accurate anti-aircraft fire, shooting down at least one German aeroplane. Davison also destroyed one German aeroplane.

By 18.20 the surviving German warplanes were out of sight as they returned to base. Some 17 US and Dutch men were killed, and at least nine others were wounded. Hartman later reported that the German warplanes had initially focused their efforts on the escorts so that they could then attack the transport vessels unopposed, but because the Allied ships returned fire accurately, the Germans suffered heavy losses and ultimately only six of the 41 vessels were damaged.

Operations to rescue survivors in the sea began even as the German attack continued. US destroyers came alongside the damaged transports and helped evacuate the crews. Beatty's crew was rescued at about 20.00 by Laub and Parker. Meanwhile, four more US destroyers and tugs from Philippeville and Algiers were sent to help. The minesweeper Pioneer rescued men from Santa Elena, and the destroyer Boyle rescued the man blown off Beatty during the following morning. Other survivors were saved by Ruys and Marnix van St Aldegonde before she grounded. While Monterey was recovering survivors, a nurse fell from the netting she was climbing, and a Chinese cook jumped overboard and saved her. In all, 6,228 persons were rescued without further loss of life.

The 169 convoys of the 'KMS' series sailed from the UK to Gibraltar and onward into the Mediterranean. The series began in October 1942 but from KMS.13 of April 1943 was combined with the OS series between the UK and Freetown, Sierra Leone, detaching en route. The first of the convoys was KMS.1 of 22 October/8 November 1942 with 49 merchant vessels and an eventual total of 17 escorts, and the last was KMS.105 that was a dispersal convoy of 30 May 1945.