Date: 25/05/1944
Squadron Code: 'S'
Serial Number: Liberator Mk.V FL 984
U-Boat details : U-990 type VIIC- attacked/sunk
:::: Flight - Mission Details ::::....

Base: Ballykelly
Time Up: 1956hrs (24th May) - Time Down: 1155hrs (25th May) - Duration: 15hrs 59mins
Op: CLA (Creeping Line Ahead) sweep

Update March 2012:

The ORB notes in July 1944, that the aircraft used on this day was Z/120. It is possible that this aircraft had recently arrived from No.120 Sqn and had yet to receive a 59 Sqn code.

F/S N.W Beames who manned the front turret gun during this attack, was awarded the D.F.M.

The Attack: 0632hrs (May 25th) U-Boat sighted

Crew: Cap. S/L B.A Sisson - 2nd Pilot: F/O R.A Williams - Nav: P/O W. Whittaker - F/L A.A Fox - F/S Beames N.W - Sgt Kelly J - F/O H Humphries - W/O W. McLoughlin - F/S Playford A.R

"...At 0632B/25 sighted U-Boat on surface escorted by 1 E/V, Co.115'/8 kts in posn. 65'05'N 07'28'E. After waiting for an opportune moment to attack under cover of rain squall "s" attacked across starboard beam of U-Boat with six 250lbs DC's spaced at 60ft. The nearest exploding 10-15 yds short of C/T. DC's No.7 and 8 hung up. U-Boat turned to port in a wide circle after attack leaving large patch of oil. E/V was last seen closing with U-Boat. Flak was experienced from both U-Boat and E/V. "S" replying with her nose turret guns. No damage to A/C or casualties. Second U-Boat Sighted: At 0803 in posn. 64'12'N 05'42'E U/B sighted in act of submerging, Co.180/5 kts "S" went into attack but as only swirl visible no attack made. Landed at Tain after sortie.


In October of 1943, 59 Sqn had Liberator Mk.V FL984 coded as "S". (Flight Log - HR Longmuir)

Sunk 25 May 1944 in North Sea west of Bodö, in position 65.05N, 07.28W, by depth charges from a British Liberator aircraft (Sqdn. 59/S). and attacked by Liberator 59/L with 20 dead and 33 survivors. Piloted by S/L Sissons. Two days later, the same aircraft (59/S) was involved in the sinking of U-292.


U-990 was sunk by multi-aircraft attack in the North Sea. One of the planes involved, Liberator 'L' of RAF 59 Squadron, was flown by RAAF Flight Sergeant A.R. Playford. Credit for the sinking went to Liberator 59/S. At the time, U-990 was also carrying a large group of survivors that it had picked up from U-476. 51 men of the combined crews escaped from U-990. A German patrol boat rescued them.




According to the Davidstow-Moor operations records, S/L Sisson had the following crew in July of 1943. It may have changed by the time of this attack.

One A/C 59 Squadron on convoy escort.

Forms 540/541 59 Squadron:
Liberator V FL984/S (click for crew and passenger list)

S/Ldr BA Sisson - Capt
P/O RA Williams - 2nd Pilot
W/O W Whittaker - Nav/B
F/O N.R. Gamble
F/O ELG Cock
P/O H Humphries
F/Sgt W McLoughlin
Sgt GLP Kammellard

Take off D/M 1038hrs, on escort to convoy KMF18. Met convoy and escorted for 7hrs 43mins in region 45:33N – 16W. Landed D/M 0249hrs 2/7/43.


According to Alywn jay in his book 'Endurance', after this attack was pressed home at approx 0730hrs, the crew were unsure of the aircrafts fuel state, so they made for Tain where they refueled (after 16 hours in the air) before returning to Ballykelly 2 hours later. Prior to sinking U-990, Sissons and crew had come upon two U-boats and a destroyer that had been attacked by Wes Loney and crew (59/L) the previous day, but 59/S was unable to attack. They had also been attacked by an E-boat. There is no mention of Liberator 59/L being involved directly in the attack on U-990 with 59/S as noted on


:::: More U-boat Details ::::....



Ordered 25 May, 1941
Laid down 17 Oct, 1942 Blohm & Voss, Hamburg (werk 190)
Launched 16 Jun, 1943
Commissioned 28 Jul, 1943 Kptlt. Hubert Nordheimer
28 Jul, 1943 - 25 May, 1944 Kptlt. Hubert Nordheimer
Career 4 patrols 28 Jul, 1943 - 31 Dec, 1943 5. Flottille (training)
1 Jan, 1944 - 25 May, 1944 11. Flottille (front boat)
Successes 1 warship sunk for a total of 1.920 tons


This U-boat belonged to the 11th Flotilla (a spanish word meaning a small group or formation of warships or submarines) The 11th emblem is shown below...


The Polar Bear - 11th Flotilla

This emblem was a fitting one for the 11th Flotilla located in Bergen, Norway. This flotilla fought in the Arctic Sea against the convoys to Russia among other things.

image © Guðmundur Helgason 1998-2000



Update June 2014:



Some of the following are posts taken from a forum, on which I am trying to identify a u-boat attack on the previous day. It's possible that one the U-boats sent out to help U-476 (of which U-990 was one of) or even U-476, is the boat in question...

"On U-boat Archive, I found an "Admiralty Report" for U-990, that shows they received a signal to aid U-476 at 12noon on the 24/05, so the time of the Catalina attack is possibly between 0143hrs and noon, given that the Cat attack seemingly stopped U-476 in her tracks... If indeed it was U-476 that a 59 Sqdn kite attacked on the 24/05.

The same report also uses what I assumed were code names for the U-boats... but they appear to be the captains names... so U-990 is Nordheimer, U-476 is Neithmann... The other U-boat I know that I found was looking for U-476 was U-921 (according to the report they left Bergen with U-990 on 22/05) was known as Leu. Three other names are mentioned that are most likely U-boats and they are Brammer, Borger and Pietsch. If this is the case then Brammer was U-1060, Borger was U-394 and Pietsch was U-344.

So now we have 5 U-boats initially sent to aid U-476. U-990, U-921, U-1060, U-394 and U-344, so obviously all operating in close enough proximity to U-476 to be considered for aiding them... Sadly, none of the above reported any attacks on the 24/05 at the recorded time of 0143hrs, but it's a start!"

It appears that U-990 reached U-476's position at 2250hrs on the 24/05 and first intentions were to take the stricken vessel in tow (back to port). 10 of the crew were taken aboard at 2257, condition report states that all engines were out of commission, rudder jammed at full starboard. At 2315, the commander of U-476 reported that the boat would only stay afloat for another two hours as the compressed air and electricity had been depleted. At 0045hrs (25/05) There were two enemy radar detection alerts and at 0102, U-476 was scuttled by U-990 with torpedoes. Three minutes later, U-990 submerged.

At 0155, U-990 surfaced to continue the search for survivors. At 0245, Vp-boat 5901 is reported to be insight. At 0330 the search for survivors is called off. Both the commander of U-990 and U-476. agreed that at 17.5 hours in (since the crippling attack on U-476), the probability of finding survivors was gone. Given this information, this would put the 210 Sqdn Catalina attack on U-476 at approximately 1000hrs on the 24/05...

Here are some excerpts from the Admiralty Report on the sinking of U-990 (source -

" Intention to sail to Narvik abandoned. Current plan: Combined Anti-Aircraft capabilities of Vp.-boat and myself strong enough to repel enemy planes. If I dive, the Vp.- boat will be destroyed. I will have to return to the surface to rescue the survivors and then it will be my turn to be attacked. Trailing Vp. 5901 at a distance of 3-400 meters enroute Trondheim."

0330: Radio message sent: Met Vp.-boat. Sailing together to Trondheim since transfer of survivors is impossible due to the sea state. Nordheimer

0640: Aircraft to port, Liberator. Maintains contact. Circles around us at a distance of 7000 meters.

0655: Radio message sent: 0655/25/9. Enemy scout plane made contact. Request immediate air cover.

0728: Under air attack from starboard. At an estimated distance of 6000 meters permission given to fire 3.7 cm. It malfunctions after just 7 rounds fired. Single fire not possible. Liberator fires with all he has. Drops 6 depth charges, similar to German versions, but slightly thinner and longer.

Last DC falls into the water around 3-5 meter away near magazine and detonate under the boat.
Violent and strong concussion. Watch on the bridge and M.G. crew thrown around. Some men were wounded by M.G. fire from plane. Boat starts to sink over the bow. Engaging E-Motors at 3/5 reverse. Engineering Officer informs me that boat will only stay afloat for a short while through continuous blow of ballast tanks 3 and 5 and watertight compartment.

0732: Orders: All men out of the boat.

0734: Heavy sea rolls over the boat. We call to Vp.-boat: Put lines into the water. Water pours in through the bridge hatch. I manage to pull Oblt. z.S. Heidt out of the hatch. I got Ob. Fähnrich z.S. Tils out up to the hips when the boat sank into the depths with us. Both Watch Officers and control room mate (Masch. Mt. Regber) had voluntarily reentered the boat to recover more emergency dinghies and floats.

Attempts to reach the Vp.-boat by swimming usually fail since the boat drifts faster than men are able to swim in the heavy sea. Since there is total destruction in the stern section of the boat, only 1 single person raft and 1 _ -person raft could be taken out of the boat. A group of 8 to 10 men cling to each raft. The Vp.-boat rescues the men that are swimming alone in the water first. The men in the water are calm, and comforting each other. Vp.-boat 5901 rescues 34 men in 75 to 90 minutes. Mtr. Hpt. Gfr. Anger dies; 18 men are missing. Rescued: Kommandant, Engineering Officer, First Watch Officer, Second Watch Officer, Ob. Strm., 8 Petty Officers and 20 men.

19.15 Moored in Trondheim.



The report from Engineering Officer Oblt. (Ing.) Bröskamp gives the following picture of the destruction that took place inside the boat:

Apparent crack in pressure hull near fuel oil bunker 2 inboard, since magazine and Kommandant's room full of oil. Stern room takes on water through torpedo tubes and torpedo loading hatch. The whole pressure hull is warped and distorted such that bulkheads are not closable anymore. All bilge pumps are out of action thanks to fractured pipes and broken or bent pump rods.

Fu.M.G. fell into the control room fuse panels and transformer fell from overhead. The Diesel air compressor was pushed amidships. Port switch panel was also pushed amidships. Periscope head broken off. Periscope pedestal broken. All lockers fell into the passageways. Barely able to get through bow room Chief Petty Officers, Officers and Kommandant's rooms because of the lockers, radio equipment and canned foodstuff.

The latter fell out of the food locker and blocked the corridor. It was impossible to recover the emergency and rescue equipment. Men were slammed against the overhead by the detonation. Boat stayed afloat due to continuing pressure blow of ballast tanks 3 and 5 and watertight compartment.
Stopped blow at 120 kg to observe boat which sank over the bow immediately. Continued blow.
Order: All men out of the boat. When there was only 40 kg of compressed air left, the Enigineering Officer was the last man to leave the interior.


Comments of "F.d.U. Norwegian" on the K.T.B. "U 990" for 12.04.44 to 25.05.44

1) Loss of the boat through air attack in unfavorable conditions after successfully lending assistance to "U-476".

2) The assistance to "U-476" (Niethmann) on 24./25.05.: The measures taken for the search for the stricken boat were thought-out and correct. The experienced commander broke off the search after rescuing 21 men and sinking the stricken U-boat, since it was improbable that the remaining life rafts were still afloat and that after 17 hours in the cold water any swimming person would be frozen to death or drowned. He deemed any further search as hopeless and that any further search would be too great of a risk to the already rescued survivors and his own boat due to enemy air operations in this area. I therefore approve of his decision, even though under more favorable conditions a further search should have yielded more certainty about the missing sailors.

3) The loss of his own boat: The Kommandant chose to sail surfaced for the purpose of air-defense, since he felt secure in the proximity of the Vp.- boat, without considering that an attack would be made against the target with the highest value and that the heavy sea would restrict the air-defense capabilities of the U-boat. After the hit and the quick sinking of the boat only 2 life rafts from the inside could be brought onto the deck. The commitment of both Watch Officers and the Control Room Mate is acknowledged. It is due to the proper operation of Vp. 5901 that, regardless of the difficult circumstances, a large portion of the shipwrecked personal could be rescued. "Nordheimer" chose all the correct options and probable solutions for the rescue of his boat.

:::: Source - & Endurance - Alwyn Jay ::::....

During WWII, the RAF used three-letter codes to identify their aircraft from a distance. Two large letters were painted before the roundel, which signified the squadron to which the aircraft belonged, and another letter was painted after the roundel which indicated the individual aircraft. Aditionally, there was the individual serial number for each aircraft, which was painted in a much smaller size, usually somewhere at the rear of the aircraft: (more)

Codes used by RAF 59 Squadron:

PJ Sep 1938 - Sep 1939
TR Sep 1939 - Oct 1942
1 Aug 1943 - Jul 1944
WE Jul 1944 - Oct 1945
BY Oct 1945 - Jun 1946, Dec 1947 - Oct 1950