Short S.25 & 26 Sunderland

Sunderlands also proved themselves in the Mediterranean theatre.

They performed valiantly in evacuations during the [Vous devez être inscrit et connecté pour voir ce lien] of [Vous devez être inscrit et connecté pour voir ce lien], carrying a surprising number of passengers, and one performed the reconnaissance mission to observe the Italian fleet at anchor in [Vous devez être inscrit et connecté pour voir ce lien] before the famous [Vous devez être inscrit et connecté pour voir ce lien]'s torpedo attack on 11 November 1940; the [Vous devez être inscrit et connecté pour voir ce lien].

New weapons made the flying boats more deadly in combat. In 1939, one 100 lb anti-submarine bomb hit [Vous devez être inscrit et connecté pour voir ce lien] merely breaking its light bulbs whilst other bombs had reportedly bounced up and hit their launch aircraft.

In early 1943 these ineffective weapons were replaced by [Vous devez être inscrit et connecté pour voir ce lien]-filled depth charges that would sink to a determined depth and then explode.

This eliminated the problem of bounce back and the shock wave propagating through the water augmented the explosive effect.

While the bright [Vous devez être inscrit et connecté pour voir ce lien] was rarely fitted to Sunderlands, ASV Mark II radar allowed the flying boats to attack U-boats on the surface.

In response, the German submarines began to carry a radar warning system known as "[Vous devez être inscrit et connecté pour voir ce lien]", also known as the "Cross of Biscay" due to the appearance of its receiving antenna that was tuned to the ASV frequency and gave the submarines early warning that an aircraft was in the area.

Kills fell off drastically until ASV Mark III radar was introduced in early 1943, which operated in the centimetric band and used antennas mounted in blisters under the wings outboard of the floats, instead of the cluttered stickleback aerials.

Sunderland Mark IIIs fitted with ASV Mark III were called Sunderland Mark IIIAs.

Centimetric radar was invisible to Metox and baffled the Germans at first.

Admiral [Vous devez être inscrit et connecté pour voir ce lien], commander of the German U-boat force, suspected that the British were being informed of submarine movements by spies.

In August 1943, a captured RAF airman misled the Germans by telling them that the aircraft were homing on the signals radiated by the Metox, and consequently U-boat commanders were instructed to turn them off.

In any case, the Germans responded by fitting U-boats with one or two 37 mm and twin quad 20 mm flak guns to shoot it out with the attackers.

While Sunderlands could suppress flak to an extent by hosing the U-boat with their nose turret guns, the U-boats had the edge by far in range and hitting power.

To help improve the odds, the Australians first fitted their aircraft in the field with an additional four .303s in fixed
mounts in the nose, allowing the pilot to add fire while diving on the submarine before bomb release.

Most aircraft were similarly modified.

The addition of single .50 inch (12.7 mm) flexibly mounted [Vous devez être inscrit et connecté pour voir ce lien] in the (previously emptied) beam hatches behind and above the wing trailing edge also became common.

The rifle calibre .303 guns lacked hitting power but the Sunderland retained its reputation for being able to take care of itself.

This reputation was enhanced by an air battle between eight Junkers Ju 88C long range [Vous devez être inscrit et connecté pour voir ce lien] and a single RAAF Sunderland Mark III of [Vous devez être inscrit et connecté pour voir ce lien] on 2 June 1943.

This was one of several stories of the type's operations related by author [Vous devez être inscrit et connecté pour voir ce lien], who flew in Sunderlands during the war.

There were 11 crewmen on board the Sunderland; nine Australians and two British.

The aircraft was on an anti-submarine patrol and also searching for remains of [Vous devez être inscrit et connecté pour voir ce lien], an airliner that had left [Vous devez être inscrit et connecté pour voir ce lien] the day before and subsequently had been shot down over the [Vous devez être inscrit et connecté pour voir ce lien].

In the late afternoon, one of the crew spotted the eight Ju 88s. Bombs and depth charges were dumped while and the engines "redlined" .

Two Ju 88s made passes at the flying boat, one from each side, scoring hits and disabling one engine while the Sunderland went through wild "corkscrew" evasive manoeuvres.

On the third pass, the dorsal turret gunner shot one down.

Another Ju 88 disabled the tail turret but the next one that made a pass was hit by both the dorsal and nose turrets and shot down.

Another attacked, destroying the Sunderland's radio gear, wounding most of the crew to varying degrees and mortally wounding one of the side gunners.

A Ju 88 tried to attack from the rear but the tail turret gunner had regained some control over the turret and shot it down.

The surviving Ju 88s continued to attack but the nose gunner damaged one of these, setting its engines on fire.

Two more of the attackers were also hit and the final pair disengaged and departed, the only two that made it back to base.

The Sunderland had been heavily damaged.

The crew threw everything they could overboard and nursed the aircraft back to the [Vous devez être inscrit et connecté pour voir ce lien] coast, where Walker managed to land and beach it at [Vous devez être inscrit et connecté pour voir ce lien].

The crew waded ashore, carrying their dead comrade, while the surf broke the Sunderland up.

The pilot Colin Walker received the [Vous devez être inscrit et connecté pour voir ce lien] and several of the other crew members also received medals.

With the exception of Walker the crew returned to Sunderlands - they disappeared without trace over the Bay of Biscay two months later after reporting that they were under attack by six Ju 88s.

Dessin vu sur le site russe airwar ( ou rusjet )


[Vous devez être inscrit et connecté pour voir ce lien]

[Vous devez être inscrit et connecté pour voir cette image]

Postwar


At the end of the Second World War, a number of new Sunderlands built at [Vous devez être inscrit et connecté pour voir ce lien] were simply taken out to sea and scuttled as there was nothing else to do with them.

In Europe it was removed from service relatively quickly but in the Far East, where well developed runways were less common and large land based maritime patrol aircraft like the new [Vous devez être inscrit et connecté pour voir ce lien] could not be used so easily, there was still a need for it, and it remained in service with the [Vous devez être inscrit et connecté pour voir ce lien] at [Vous devez être inscrit et connecté pour voir ce lien] until 1959, and with the [Vous devez être inscrit et connecté pour voir ce lien]'s [Vous devez être inscrit et connecté pour voir ce lien] and [Vous devez être inscrit et connecté pour voir ce lien] until 1967.

During the [Vous devez être inscrit et connecté pour voir ce lien] (June 1948 - August 1949) 10 Sunderlands and two [Vous devez être inscrit et connecté pour voir ce lien] were used to transport goods from [Vous devez être inscrit et connecté pour voir ce lien] on the [Vous devez être inscrit et connecté pour voir ce lien] near [Vous devez être inscrit et connecté pour voir ce lien] to the isolated city, landing on the [Vous devez être inscrit et connecté pour voir ce lien] lake beside [Vous devez être inscrit et connecté pour voir ce lien] until it iced over.

The Sunderlands were particularly used for transporting [Vous devez être inscrit et connecté pour voir ce lien], as their airframes were already protected against corrosion from [Vous devez être inscrit et connecté pour voir ce lien].

Transporting salt in standard aircraft risked rapid and severe structural corrosion in the event of a spillage.

This is the only known operational use of flying boats within central Europe.

The [Vous devez être inscrit et connecté pour voir ce lien], which received Sunderlands when it was formed in 1943 as [Vous devez être inscrit et connecté pour voir ce lien], continued to operate them until December 1960, the last unit to operate Sunderlands in the Northern Hemisphere.

From mid-1950, RAF Sunderlands also saw service during the [Vous devez être inscrit et connecté pour voir ce lien] initially with No. 88 Squadron but shortly followed by Nos. 205 and 209 Squadrons.

The three squadrons shared the operational task equally with rotational detachments of three or four aircraft and crews based at Iwakuni, Japan.

Missions lasting 10 to 13 hours were flown daily throughout the war, and also during the Armistice period that followed, until September 1954.

The Sunderland also saw service with the Royal New Zealand Air Force until the mid-1960s.

Variants


Prototype


The first S.25, now named the Sunderland Mark I, flew from the [Vous devez être inscrit et connecté pour voir ce lien] on 16 October 1937 with Shorts' [Vous devez être inscrit et connecté pour voir ce lien], [Vous devez être inscrit et connecté pour voir ce lien] at the controls.

The deeper hull and installation of nose and tail turrets gave the Sunderland a considerably different appearance from the Empire flying boats.

The prototype was fitted with [Vous devez être inscrit et connecté pour voir ce lien] X engines, each providing 950 hp (709 kW ), as the planned Pegasus XXII engines of 1,010 hp (753 kW) were not available at the time.

The 37 mm gun, originally intended as a primary anti-submarine weapon, was dropped from the plans during the prototype phase and replaced with a Nash & Thomson FN-11 nose turret mounting a single [Vous devez être inscrit et connecté pour voir ce lien] machine gun.

The turret could be winched back into the nose, revealing a small "deck" and demountable marine [Vous devez être inscrit et connecté pour voir ce lien] used during mooring manoeuvres on the water.

The change of armament in the nose to the much lighter gun moved the [Vous devez être inscrit et connecté pour voir ce lien] rearwards.

After the first series of flights the aircraft was returned to the workshop and the wing was swept 4.25° to the rear, thereby moving the [Vous devez être inscrit et connecté pour voir ce lien] into a more reasonable position in relation to the new centre of gravity.

This left the engines and wing floats canted out from the aircraft's centreline.

Although the wing loading was much higher than that of any previous Royal Air Force flying boat, a new [Vous devez être inscrit et connecté pour voir ce lien] system kept the takeoff run to a reasonable length and the aircraft first flew with the new wing sweep and the uprated
Pegasus XXII engines on 7 March 1938.

Official enthusiasm for the type had been so great that in March 1936, well before the first flight of the prototype, the Air Ministry ordered 21 production examples.

Meanwhile, delivery of the other contender [Vous devez être inscrit et connecté pour voir ce lien] was delayed and it did not fly until October 1938.

The aircraft was written off after it suffered structural failure during high speed taxi trials and no other prototypes were built.

Sunderland Mark I



The RAF received its first Sunderland Mark I in June 1938 when the second production aircraft (L2159) was flown to [Vous devez être inscrit et connecté pour voir ce lien] at [Vous devez être inscrit et connecté pour voir ce lien], [Vous devez être inscrit et connecté pour voir ce lien].

By the outbreak of war in Europe, in September 1939, [Vous devez être inscrit et connecté pour voir ce lien] was operating 40 Sunderlands.

The main offensive load was up to 2,000 lb (910 kg) of [Vous devez être inscrit et connecté pour voir ce lien] (usually 250 or 500 lb), [Vous devez être inscrit et connecté pour voir ce lien] (1,000 lb) or other stores that were hung on traversing racks under the wing centre section (to and from the bomb room in the fuselage).

Later, depth charges (usually 250 lb) were added.

By late 1940 two [Vous devez être inscrit et connecté pour voir ce lien] had been added to new hatches that were inserted into the upper sides of the fuselage just aft of the wing, with appropriate slipstream deflectors.

A second gun was added to the nose turret. New constant speed propellers and deicing boots were installed as well during 1940.

As the defensive weaponry improved the aircraft became a formidable foe, even though it was far from base, travelled fairly slowly (120 knots and down to about 90 kt for long range cruise) and was usually at low altitude.

But a Sunderland off Norway on 3 April 1940 was attacked by six [Vous devez être inscrit et connecté pour voir ce lien] with the result that one was shot down, one forced to immediately land and the others went home, much wiser.

Later, over the Bay of Biscay eight Ju 88 attacked one Sunderland escorting a convoy and three were shot down by the patrol aircraft.

A Sunderland made the vital reconnaissance of [Vous devez être inscrit et connecté pour voir ce lien] before the Royal Navy's [Vous devez être inscrit et connecté pour voir ce lien] on 11 November 1940.

The aircraft was not a great success at landing and taking off from rough water, but, other than in the open sea, it could be handled onto and off a short chop, by a skilled pilot.

Many rescues were made, early in the war, of crews that were in the Channel having abandoned or ditched their aircraft, or abandoned their ship.

In May 1941, during the [Vous devez être inscrit et connecté pour voir ce lien] Sunderland transported as many as 82 armed men from place to place in one load.

Steep ocean swells were never attempted, however a calm ocean could be suitable for landing and takeoff.

Beginning in October 1941, Sunderlands were fitted with ASV Mark II "Air to Surface Vessel" [Vous devez être inscrit et connecté pour voir ce lien] .

This was a primitive low frequency radar system operating at a wavelength of 1.5 m.

It used a row of four prominent "stickleback" [Vous devez être inscrit et connecté pour voir ce lien] on top of the rear fuselage, two rows of four smaller aerials on either side of the fuselage beneath the stickleback antennas, and a single receiving aerial mounted under each wing outboard of the float and angled outward.

A total of 75 Sunderland Mark I were built: 60 at Shorts' factories at Rochester and [Vous devez être inscrit et connecté pour voir ce lien], and 15 by [Vous devez être inscrit et connecté pour voir ce lien] at [Vous devez être inscrit et connecté pour voir ce lien].

The RAF allocated the AP1566 series of air publications to the Sunderland.

Sunderland Mark II


In August 1941, production moved on to the Sunderland Mark II which used Pegasus XVIII engines with two-speed superchargers, producing 1,065 hp (794 kW) each.

The tail turret was changed to an FN.4A turret that retained the four .303 guns of its predecessor but provided twice the ammunition capacity with 1,000 rounds per gun.

Late production Mark IIs also had an FN.7 dorsal turret, mounted offset to the right just behind the wings and fitted with twin .303 machine guns.

The hand held guns behind the wing were removed in these versions.

Only 43 Mark IIs were built, five of these by Blackburn.

Dessin vu chez airwar.ru. Le très bon site russe

[Vous devez être inscrit et connecté pour voir cette image]

Sunderland Mark III


Production quickly went on in December 1941 to the Sunderland Mark III which featured a revised hull configuration which had been tested on a Mark I the previous June.

This modification improved seaworthiness, which had suffered as the weight of the Sunderland increased with new marks and field changes.

In earlier Sunderlands, the hull "step" that allows a flying boat to "unstick" from the surface of the sea was an abrupt one, but in the Mk III it was a curve upwards from the forward hull line.

The Mark III turned out to be the definitive Sunderland variant, with 461 built.

Most were built by Shorts at Rochester and Belfast, a further 35 at a new (but temporary) Shorts plant at White Cross Bay, [Vous devez être inscrit et connecté pour voir ce lien]; while 170 were built by Blackburn Aircraft.

The Sunderland Mark III proved to be one of the RAF Coastal Command's major weapons against the U-boats, along with the [Vous devez être inscrit et connecté pour voir ce lien].

As the [Vous devez être inscrit et connecté pour voir ce lien] began to use [Vous devez être inscrit et connecté pour voir ce lien] passive receivers the ASV Mk II radar gave away the presence of aircraft and the number of sightings diminished drastically.

The RAF response was to upgrade to the ASV Mk III, which operated in the 50 cm band, with antennas that could be faired into fewer more streamlined blisters.

During the Mk III's life there were a large number of almost continuous improvements made, including the ASV Mk IIIA and four more machine guns in a fixed position in the wall of the forward fuselage just behind the turret (developed on RAAF aircraft first) with a simple bead and ring sight for the pilot.

Despite the 14-hour-long patrols expected of their crews, early Sunderland gunners were provided with only 500 rounds of ammunition each. Later 1,000 round ammunition boxes were installed in the turrets.

The beam hatch guns were removed from Mk II aircraft but Mk IIIs and then Mk Is gained much more capable
[Vous devez être inscrit et connecté pour voir ce lien], one each side.

Offensive weapons loads increased too. The introduction of the hydrostatically fused 250 lb (110 kg) [Vous devez être inscrit et connecté pour voir ce lien] meant that additional weapons could be carried on the floor of the bomb room in wooden restraints, along with
ammunition boxes of 10 and 25 lb anti-personnel bombs that could be hand launched from various hatches to harass
U-boat crews otherwise manning the twin 37 and dual quadruple 20 mm cannons that U-boats were fitted with.

As radar detection became more effective there were more night patrols to catch U-boats on the surface charging their batteries.

Attacking in the dark was a problem that was solved by carrying one inch (25.4 mm), electrically initiated flares and dropping then out of the rear chute of the aircraft as it got close to the surface vessel.

Sunderlands never carried [Vous devez être inscrit et connecté pour voir ce lien], probably because the flares were sufficient.

By this time the crew workload had increased so much that it needed at least 10 to crew the aircraft.

During attacks they were sorely pressed to get all of the necessary work done and crews took many shortcuts that possibly proved fatal in some cases.

In early 1944 the ordnance load in the aircraft and the long length of patrols, meaning maximum fuel loads, required that much more powerful engines were needed.

It was decided to fit 1,200 hp (890 kW) [Vous devez être inscrit et connecté pour voir ce lien], Twin Wasp, powerplants.

These were commonly available and maintenance crews on [Vous devez être inscrit et connecté pour voir ce lien], [Vous devez être inscrit et connecté pour voir ce lien] and [Vous devez être inscrit et connecté pour voir ce lien] aircraft were familiar with them.

This lead to the production of the Mk V aircraft.