These submarines roamed the Atlantic with impunity as no allied aircraft had the range to seek out and destroy the submarine Wolf Packs that were sending thousands of tons of ships and war materials to the bottom of the ocean. One of the answers to this dilemma was found in the Short Sunderland flying-boat, a truly remarkable aircraft and mechanical wonder in many respects. It had great endurance, and carried the latest anti-submarine detection equipment and specialized sea-war weaponry.

The Royal Air Force prior to the outbreak of hostilities was using Sunderlands in a maritime patrol capacity and when it entered war service, was the largest allied aircraft flown during World War 2. The Sunderland was sometimes nicknamed “The Pig” by its crews because the early models were underpowered. The Luftwaffe pilots that tried to attack it had more respect for this huge aircraft and referred to it as the; “Fliegende Stachelschwein” or in English, “The Flying Porcupine” because of the 14 machine guns it mounted for all-round protection.

As if that wasn’t enough armament, the RAAF thought it prudent to add two fixed .303 machine guns to the Mk.V on the port and starboard side of the nose and a gun-sight for the pilot so he would be able to strafe a surfaced enemy submarine. The flying boat now sprouted 18 guns, the greatest number carried by any regular British military aircraft during the war.

The Sunderland had one vulnerable area and that was the belly. Because of the boat design it could not mount a belly turret. So in order to prevent the enemy aircraft from coming up and underneath, they flew their patrols at a maximum height of 1000 feet above the water, but usually much lower than that.

The fuselage design also prohibited the installation of a bomb bay, so the designer came up with a unique method to store, mount and dispense light ordnance. These stores were hung inside the fuselage and under the centre-section of the wing on carriers that ran on lateral tracks. In combat, large fuselage side panels were opened under the wing root and a drive motor ran out the weapon rack under each wing.

After the explosives were dropped, the racks were brought back in and reloaded. The Sunderland’s maximum ordnance load was approximately 2250 kilograms of bombs, depth charges, mines or other stores which were kept in the “stores and loading room” beneath the wing racks and in the lower part of the fuselage.

Two Canadian squadrons flew Sunderlands from bases in Scotland, Ireland and Wales. No. 422 (Flying Yachtsmen) Squadron was formed on 2 April 1942 at Lough Erne, Northern Ireland and was initially equipped with the Consolidated Catalina, then Sunderland Mk IIIs. At the end of February 1943 it began the work for which it had been formed, anti-submarine duties over the Atlantic, and commenced operations from Oban, Scotland.

For the most part the squadron's duties were dull and monotonous, flying for hours over the empty ocean with little action. Occasional attacks were made on U-boats, some with success. In early 1945 the squadron had its most successful actions, with four U- boat attacks in four days.

No. 423 Squadron was formed on 18 May 1942 at Oban, Argyll, Scotland. Its first aircraft, Sunderland Mk IIs and Mk IIIs, arrived in July and the squadron’s first mission was flown on 23 August 1942. Within the next two months it had attacked four submarines and destroyed two of them. By autumn 1942 it was flying patrols from Castle Archdale, Ireland to Gibraltar and back, covering the Biscay area en route. It increased its operational intensity during 1944, being especially busy during the invasion of Normandy.

The anti-submarine work continued through to the war's end in Europe, by which time the squadron had sunk three U- boats, and shared in the sinking of three more. The most notable Sunderland sortie was over the Bay of Biscay. The skipper would patrol during daylight and set down on the sea at night, shut down the engines and drift with the swells. This routine continued for seven days when low provisions and fuel forced them back to base. Unfortunately this long and arduous patrol did not result in any contact with enemy ships or aircraft.

By wars end, 422 and 423 Squadrons would fly 2508 operational sorties, log over 40,000 hours, lose 15 aircraft on operations and suffer 101 men killed. There were also accidents, often on take-off or landing or crashing into terrain in bad weather. Another culprit was engine failure.

When heavily laden a Sunderland could not maintain height on three engines which would oblige the skipper to set down, often with disastrous results to both crew and aircraft. If an engine failed over land, the results were predictable.

In August 1945, all contracts were cancelled. Dozens of new “boats” were packed with new military equipment and deliberately sunk shortly after the end of the war. The last of these well loved flying-boats was retired from the RAF on 20 May 1959. It had set a record of 21 years continuous service in the same oceanic duty, and had also performed many other remarkable feats.

In conclusion, the Sunderland was the gentle giant of its day. While the battles it fought were not glorious ones, its presence above the waves forced the enemy U-boats to keep their distance from allied convoys thus allowing more war supplies to reach their destinations. They were also instrumental in saving the lives of many downed airmen and torpedoed sailors who were then able to return to their units and fight another day.