21 Feb 1941
The boat was attacked by an aircraft in the North Atlantic, suffering some damage.

28 Apr 1941
After torpedoing a ship in convoy HX 121 south of Iceland, U-552 was depth charged in five separate attacks from the escorting destroyers HMS Maori and HMS Inglefield, forcing the boat to remain submerged for hours until the convoy was out of range. (Sources: Blair, vol 1, page 272)

18 Jun 1941
After locating an inbound convoy Topp attempted to attack and bring in other boats, but was driven off by the escorts. (Sources: Blair, vol 1, page 307)

1 Oct 1941
A Hudson bomber dropped one bomb which caused minor damage.

25 Nov 1941

U-552 was detected and bombed by an aircraft.

Attack report by the aircraft, Hudson 'A' from 53 Sq. RAF;

Time: 1240A/25. Position: 47°31'N, 08°28'W. Depth of water: 1200 fathoms. Weather conditions: wind 297°, 12 knots, weather fine, visibility 15 miles.

While flying an A/S patrol a suspicious wash was sighted on the port beam 12 miles distant. Course was altered to investigate and a fully surfaced U-boat was subsequently sighted three miles away. The enemy was steering a course of about 090° at 12 knots. The aircraft then dived to attack from 50 feet. The U-boat commenced to submerge 15 seconds before the attack but the conning tower was still above the water when the attack was made. The aircraft approached at an angle of 30° to the U-boats track and released one depth charge set to 50 feet. The second and third depth charges hung up. The depth charge was seen to explode alongside the conning tower and 15 deet to starboard of it. The stern of the U-boat tilted out of the water as the depth charge exploded. This was attributed to the speed at which the U-boat dived.

The aircraft subsequently patrolled the area for 40 minutes while the depth charge release. One of the depth charges which had hung up was dropped, the other was brought back home. After 40 minutes the aircraft commenced to patrol on the U-boats expected track.

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Report of U-552;

1339B/25, In quadrant BF 4294 (which was centred in position 47°33'N, 08°55'W) an aircraft was sighted at a range of only 1000 meters. Crash dived. When to hatch was closed, the aircraft, a Lockhead Hudson, was already over the boat. Apparently the attack failed or the bombs / depth charges did not explode. In a second attack run a bomb / depth charge was dropped which exploded when U-552 had reached a depth of 50 meters. No damage was sustained except for the ego of the bridge watch officer. U-552 returned to periscope depth at 1440B/25 and surfaced at 1547B/25.

(Sources: ADM 199/1782 + KTB U-552 6 October to 26 November 1941 (NARA, T 1022, roll 2981, PG 30589/6))

25 Nov 1941

U-552 was again detected and bombed by an aircraft.

Attack report by the aircraft, Hudson 'A' from 53 Sq. RAF;

Time: 1503A/25. Position: 47°36'N, 08°12'W. Depth of water: 1200 fathoms. Weather conditions: wind 297°, 12 knots, weather fine, visibility 15 miles.

While patrolling ahead, on the expected track, of the U-boat attacked at 1240A/25 sighted a U-boat at a range of 6 miles. The enemy was steering 110° at 12 knots. Climed to 2000 feet and delivered a dive bombing attack out of the sun diving towards the U-boat's starboard beam. The U-boat's conning was still above the water when the bomb was dropped. After the attack, patrolled in the area for 18 minutes but nothing further was seen.

Submarine tracking room's opinion;

Tracking evidence suggests that both attacks (1240A/25 and 1503A/25) were made on the same U-boat and that this U-boat continued its passage to a home port without damage.

Decision of the U-boat assessment committee;

The committee accepts the fact that both attacks (1240A/25 and 1503A/25) were made on the same U-boat and it is noted that one depth charge fell at an estimated distance of 15 feet from the hull and one A/S bomb at a distance of 36 feet from the hull. Taking the visible errors of depth into account it does not seem likely that either of these explosions inflicted damage on the enemy and the result is assessed as 'insufficient evidence of damage'.

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Report of U-552;

1603B/25, In quadrant BF 4294 (which was centred in position 47°33'N, 08°55'W), sighted an aircraft closing at a fairly high altitude. Crash dived. The aircraft dropped a badly aimed bomb which exploded at a depth of 10 meters. No damage was sustained. Surfaced at 1751B/25.

(Sources: ADM 199/1782 + KTB U-552 6 October to 26 November 1941 (NARA, T 1022, roll 2981, PG 30589/6))

17 Jan 1942
U-552 was attacked by a "destroyer" after firing torpedoes at a freighter escorted by 2 "destroyers". The boat escaped undamaged. (Sources: Blair, vol 1, page 471)

20 Nov 1942
While enroute to the USA to be refitted at the Philadelphia Navy Yard, the Dutch submarine HrMs K XIV (Lt.Cdr. J.H. Geijs) attacked U-552 south of the Cape Verde Islands in position 13º05N, 25º50W. K XIV launched four torpedoes from distance of around 900m. The torpedoes were from old stores in the Netherlands East Indies and ran close to the surface, were detected by the Germans and missed their target as the U-boat took evasive action.

27 May 1943
Mid-Atlantic: a British B-24 Liberator bomber (59 Sqn RAF, pilot H.A.L. Moran) made two passes before the boat escaped, dropping a total of eight depth charges. Despite severe damage, the boat survived and managed to reach port on June 13. (Sources: Blair, vol 2, page 340)

9 recorded attacks on this boat.