25 Jan, 1941
At night, the 7th Destroyer Flotilla (including Piorun) left Scapa Flow with main forces of Home Fleet. The Allied ships were trying to intercept the German battlecrusiers Scharnhorst and Gneisenau that were breaking into the Atlantic. The 7th Destroyer Flotilla was ordered to provide cover for HMS Nelson, HMS Rodney and HMS Repulse.

27 Jan, 1941
The Allied forces had to split. Piorun and two British destroyers were ordered to escort the battleship HMS Rodney and the light crusier HMS Edinburgh.

28 Jan, 1941
Piorun and HMS Keppel are forced to return to base due to damages caused by a storm.

8 Feb, 1941
The Polish destroyers Garland and Piorun formed part of the escort of a convoy bound for Canada / USA.

12 Feb, 1941
The Polish destroyers Piorun, Garland and the British destroyer HMS Legion conduct an offensive patrol against enemy submarines. However, no U-boat was encoutered.

17 Feb, 1941
Garland and Piorun were once again part of the Escort for a convoy.

20 Feb, 1941
The Polish destroyers Garland and Piorun were ordered to leave a convoy they were escorting and provide escort for two troop ships returning to England.

24 Mar, 1941
Piorun and British destroyers escorted a convoy to USA. The convoy was also protected by the battleships HMS Rodney and HMS Nelson and the light cruisers HMS Edinburgh and HMS Cairo, this was due to the fact that the German battlecruisers Scharnhorst and Gneisenau were operating in the North Atlantic.

26 Mar, 1941
The destroyers left the outbound convoy and joined another convoy heading to England.

5 Apr, 1941
The British battleship HMS Resolution and the Polish destroyers Garland and Piorun escorted troop ships to Hvalfjord, Iceland. They arrived in Iceland on the 9th.

13 Apr, 1941
Two destroyers, HMS "Legion" and ORP "Piorun", were ordered to rescue survivors from AMC "Rajputana". The ships picked up 283 men.

14 Apr, 1941
HMS Rodney, HMS Legion, Piorun and Garland composed the escort of two troop ships heading from Iceland to the Clyde.

26 Apr, 1941
Piorun was part of the escort of large convoy bound for the Middle East.

30 Apr, 1941
Piorun and four British destroyers were ordered to join four troop ships returning from the Middle East to the U.K.

3 May, 1941
The convoy reached the Clyde without losses. Piorun was sent for repairs which lasted to 20 May 1941.

25 May, 1941
The 4th Destroyer Flotilla comprising the British destroyers HMS Cossack (Capt. P.L. Vian, DSO, RN), HMS Maori (Cdr. H.T. Armstrong, DSO, RN), HMS Sikh (Cdr. G.H. Stokes, RN), HMS Zulu (Cdr. H.R. Graham, DSO, RN) and the Polish destroyer Piorun (Cdr. E. Plawski, Polish Navy) was escorting convoy WS-8B when they recieved an order to leave the convoy and take part in the hunt for the German battleship Bismarck.

26 May, 1941
At 11.00 AM Capt. Vian (in HMS Cossack) recieved a radio report about the position of the Bismarck. He realized that the 4th Destroyer Flotilla was only 50 miles away and ordered to chase the enemy. Due to bad weather and high waves, the destroyers were able to maintain 27 knots speed (only two knots more than Bismarck), but continued the pursuit. Fortunately, British aircraft managed to hit the enemy with two torpedoes. One of them jammed the rudder and damaged the screws. The allied destroyers steamed in line formation, one about 25 cables from another. In darkness, Piorun lost contact with her British partners. At 2214hours lookouts spotted a large ship which indentified herself as HMS Sheffield. At 2237 lookouts detected another large ship. The Polish commanding officer Cdr. Plawski was afraid of attacking the unidentified vessel, because it could be HMS Sheffield again. Piorun used an Aldis lamp to transmit a signal. The answer was 6" gunfire, The detected ship was the Bismarck!!! Cdr. Plawski ordered to open fire with the six 4.7" guns. During 59 minutes Piorun continued transmitting radio reports and traded fire with German battleship achieving several hits. Of course, 4.7" shells were able only to destroy some light AA guns, but not to penetrate heavy armor. The Polish destroyer was making lot of evasive manouvers, because Bismarck also used her 15" main armament. The British destroyers appeared on scene and conducted a torpedo attack against the Geran battleship. But all torpedoes missed the target. At 2336hours Piorun lost contact with the enemy.

27 May, 1941
Piorun continued searching for the German battleship, but only detected her own flagship HMS Cossack. At 05.00 AM Capt. Vian ordered Piorun to break off the action and return to base due to fuel shortage. However, the Polish destroyer tried to find the enemy for one more hour. At 06.00 AM Cdr. Plawski ordered to change course and head for Plymouth.

28 May, 1941
Piorun reached Plymouth with only 37 tons of fuel left in her tanks.

2 Sep, 1941
The Polish destroyers Piorun and Garland depart Liverpool to conduct a ASW patrol.

3 Sep, 1941
The Polish destroyers Piorun and Garland are ordered to pick up the survivors from the British merchant Fort Richepanche that was torpedoed that day by the German submarine U-567 some 450 miles southwest of Bloody Foreland in position 52.15N, 21.10W. Ten crew members, five gunners and seven passengers were picked up by the Polish destroyers on 4 September and landed at Greenock on 5 September (see map)

17 Oct, 1941
The Polish destroyers Piorun and Garland depart Gourock as part of the escort of a convoy to Canada.

24 Oct, 1941
The Polish destroyers Piorun and Garland were detached from convoy they are escorting in order to reach St. John's, Canada for refueling. Five and half hours after they reach the harbour they depart again and head back to the convoy.

26 Oct, 1941
The Polish destroyers Piorun and Garland reach Halifax, Canada with the convoy they are escorting.

4 Nov, 1941
The Polish destroyers Piorun and Garland depart Halifax, Canada as part of the escort for a convoy to the Clyde.

12 Nov, 1941
The Polish destroyers Piorun and Garland enter Greenock harbor.

14 Nov, 1941
Piorun arrives at Glassgow for general repairs.

12 Feb, 1942
Piorun (Lt. Cdr. Hryniewiecki) is ordered to make a ASW search in the Irish Sea to find and neutralize a u-boat reported there. The search is unsuccessful.

13 Feb, 1942
Piorun returns to Gourock.

26 Feb, 1942
Piorun became part of the escort of a convoy to Canada.

28 Feb, 1942
The convoy Piorun is escorting was caught by a strong storm. The Polish ship suffered no damage.

11 Mar, 1942
At night Polish lookouts on Piorun spotted a surfaced U-boat trying to slip into the convoy. The Germans also spotted the destroyer as the U-boat submerged. She was detected by the asdic and attacked with depth charges. After this attack, contact was lost and the Germans managed to slip away.

12 Mar, 1942
Piorun entered St. John's, Canada.

17 Mar, 1942
Piorun came to Argentia, Canada.

21 Mar, 1942
Piorun departs Canada as part of the escort of a convoy to Great Britain.

27 Mar, 1942
Piorun met a lonely Norwegian tanker. A boarding party inspected the tankers documents and she is ordered to join the convoy.

29 Mar, 1942
Piorun meets another tanker. This time it was a British vessel which was also ordered to join the convoy.

1 Apr, 1942
The convoy, of which Piorun is part of the escorts reaches Gourock.

8 Apr, 1942
After boiler cleaning Piorun was loaded with British gold in order to transport this cargo to Canada. At 16.30hours the Polish ship left Gourock and later that day entered Londonderry.

9 Apr, 1942
Piorun departs Londonderry and joined the escort of a convoy to Canada.

16 Apr, 1942
Piorun entered Halifax harbor where the gold was unloaded.

26 Apr, 1942
Piorun left Argentia, Canada with a convoy to Great Britain.

9 May, 1942
Piorun reached Greenock.

31 May, 1942
Piorun was involved in the escort of another convoy to Canada.

2 Jun, 1942
Piorun attacked two submerged U-boats.

4 Jun, 1942
Around 17.00hours Piorun dropped depth charges on an enemy U-boat.

8 Jun, 1942
The convoy Piorun is escorting reaches Canada.

16 Jun, 1942
Piorun departs Canada as part of the escort of a convoy to Great Britain.

20 Jun, 1942
The convoy Piorun is escorting is cought by a heavy storm.

25 Jun, 1942
Piorun reached Greenock.

5 Jul, 1942
Piorun departs Great Britain with a convoy to Canada.

12 Jul, 1942
During a storm, the convoy was attacked by U-boats. Piorun dropped depth charges twice.

20 Jul, 1942
Piorun arrives at Argentia, Canada.

14 Aug, 1942
Piorun departs Canada as part of the escort of a convoy to Great Britain.

17 Aug, 1942
Piorun is damaged during a storm.

20 Aug, 1942
Piorun arrives at Gourock. She has go undergo some repairs.

30 Aug, 1942
Piorun arrives at Londonderry.

31 Aug, 1942
Piorun became part of the escort of a convoy to Canada.

10 Sep, 1942
The convoy Piorun is escorting reached Canada. The convoys escort entered St. John's.

11 Sep, 1942
Piorun left St. John's as escort of a convoy to Argentia.

14 Sep, 1942
Piorun arrives at Argentia, Canada.

15 Sep, 1942
Piorun joined the escort of a convoy to Great Britain.

24 Sep, 1942
Piorun enteres Gourock and was sent off for general repairs.