HMS Audacity: The Pioneering Escort Carrier in World War II

As the Royal Navy’s first escort carrier, HMS Audacity occupies a special place in naval history for this vessel and those like her that sat between the world of merchant shipping and naval operations during the war. Converted from the German cargo liner Hannover – which had been captured by the British in 1940 – Audacity first sailed in 1941, and quickly became a powerhouse in the Atlantic war. Although her career was short, being in service between June and December 1941, Audacity's pioneering of convoy air protection and attacks on German U-boats and aircraft in the Atlantic allowed the Allies to undercut German naval strategy. This paper considers Audacity’s design, her unique features and operating principles, as well as her vital contributions to critical World War II engagements, most notably in the Atlantic theater where she helped write a new chapter in the use of air power at sea.

Design of HMS Audacity

Origins and Conversion

Hannover had been a German merchant ship, originally launched as cargo liner 5,537 gross register tonnage (GRT) Hannover by Bremer Vulkan Schiff- und Maschinenbau at Vegesack on 29 March 1939. She belonged to Norddeutscher Lloyd, and made the “banana run” between Germany and West Indies. When the Second World War began, the ship took shelter at Curaçao, Netherlands Antilles, but in March 1940, Aviso Grille attempted to run the British blockade to return to Germany. Interception On the night of 7–8 March 1940, HMS Dunedin and HMCS Assiniboine discovered Hannover near Santo Domingo Cape Engano. British efforts to scuttle the ship were thwarted, though, by German resistance and the British put the fires out and towed Edam to Jamaica, where she was repaired and placed in service as SS Sinbad, sailing under the British merchant ensign.

On 19 November 1940 she was renamed Empire Audacity and utilized for a brief period as an ocean boarding vessel enforcing blockades. However, with the Allies' convoys lacking air cover in the Mid-Atlantic Gap where there were no land bases available, the Admiralty chose to take the vessel in hand and convert her into an escort carrier. Iran – Empire Audacity was acquired by the Ministry of War Transport (MoWT) on 22 January 1941 and transferred to Blyth Dry Docks & Shipbuilding Co. Ltd., Blyth, England for conversion to an escort carrier. She was converted by 17 June 1941, with substantial removal of merchant superstructure and installation of a 465 ft flight deck; she was the largest vessel handled at Blyth, a yard used to much smaller ships amongst the trawlers and colliers. The vessel's construction was renamed to HMS Audacity on 31 July 1941 and the ship was given the pendant number D10.

Technical Specifications

Design HMS Audacity was an exercise in compromise, its merchant origins, makeshift war conditions and extraordinary urgency being all too visible in her design. She was 441 feet long, with a beam of 56 feet and a draught of 23 feet. They were moved by diesel engines at a top speed of 15 knots, which was sufficient for convoy escort, but slow in comparison to fleet carriers. The conversion favored utility over finesse: Audacity lacked a hangar deck or an elevator, and all her aircraft were stored and serviced on the open flight deck. This restricted it to an additional six to eight Grumman Martlet (F4F Wildcat) fighters of 802 Naval Air Squadron, Fleet Air Arm, stowed on deck and exposed to the elements.

The vessel was lightly armed but able to perform its task. Armament consisted of a single 4-inch (100mm) gun for screen smoke and one 6-pounder (57mm) gun located on the aft deck, with four 2-pounder AA guns on forward sponsons and four 20mm AA cannon on deck and lower hull sponsons. Audacity was fitted with Type 79B air warning radar, an early type with a range of 30-50 miles and intended to give several minutes warning of attacking aircraft to fighters receiving launch instructions. It was also equipped with minesweeping paravanes and two depth charge throwers but relied on its planes and escort vessels for anti-submarine defense.

Design Limitations

Lack of hangar deck though was a major disadvantage for the exposed maintenance of aircraft in the rigours of the Atlantic which reduced operational availability. The close-set flight deck would preclude side-parking, restricting the number of aircraft to be carried. The ship's merchat hull, while stout, was not intended for extended naval combat, and it had little in the way of armor, making it susceptible to torpedoes and gunfire. These deficiencies were attributable to the haste of the conversion, yet they did not detract from Audacity’s groundbreaking status as a prototype for the escort carrier concept.

What Made HMS Audacity Special

Pioneering Escort Carrier Role

HMS Audacity was the Royal Navy’s first escort carrier, a new weapon to address the pressing issue of the Mid-Atlantic Gap, where Allied convoys were out of range of air cover land-based aircraft. Unlike the fleet carriers that were big heavily-armed ships built for offensive operations, escort carriers like Audacity were smaller converted merchantmen designed to give air cover to convoys. Audacity was used as a fighter aircraft carrier rather than being used to carry anti-submarine aircraft as later escort carrier would be doing. This emphasis on fighters was motivated by the need to counter the German Focke-Wulf Fw 200 Condor bombers, which were causing havoc on Allied shipping.

Audacity's conversion laid the groundwork for later escort carriers such as HMS Activity and USS Bogue, proving that merchant hulls could be converted into carriers for naval aircraft. Its success in proving the concept of the small carrier resulted in the construction of 122 escort carriers for the U.S. Navy alone during the war, six of these being British conversions, including Audacity. The vessel's ability to carry fighters from a merchant ship raised the overiding spectre of air cover for vulnerale convoys, reforming Allied convoy protection policies.

Notable Personnel and Achievements

Audacity’s reputation was benefited by the presence of Royal Navy super ace Eric “Winkle” Brown (a pilot with No. 802 Squadron) alongside her. Brown, who would go on to become the most successful test pilot in history, claimed his first German aircraft, a Focke-Wulf Fw 200 Condor in flying from Audacity during Convoy OG 76. His victory confirmed the formidable capabilities of Audacity’s air wing for the suppression of long-range German aircraft. The ship and its crew — Brown among them — proved to be remarkably effective at fighting while lashed together in an improvised carrier, contributing to its outsized legacy.

Strategic and Propaganda Value

The actions of Audacity also took a psychological toll on all parties. For the Allies, it was a brazen response to the U-boat and air menace, lifting spirits by showing that merchant ships also could be converted into fighting ships. Audacity, for the Germans, subsumed other targets, because its fighters disrupted the Luftwaffe's efforts. Nazi propaganda would later claim the ship had been a larger Illustrious-class aircraft carrier sunk in error, the mere fact that she had already appeared as the subject of such headlines owed much to the 'threat' perception. The short career of Audacity demonstrated the potential for escort carriers to shift the balance of the Battle of the Atlantic, leading to more advanced designs.

Key Roles in Battles

The Battle of the Atlantic

HMS Audacity helped in the main task of that was in the Battle of the Atlantic – the bitter, drawn-out struggle to defend the Allied convoy routes against the ravaging attentions of Nazi U-boats and aircraft. Between September and December 1941 Audacity accompanied four convoys between Britain and Gibraltar, flying air cover against attack by Focke-Wulf Condor bombers and, indirectly, from U-boats through co-operation with the escorting warships. Operational service Information on the Fieseler 167s operational history is very vague, this coming from its participation in Convoys OG 74, HG 74, OG 76and HG 76.

Convoy OG 74 (September 1941)

The first action involving Audacity was the sailing of Convoy OG 74 from Britain to Gibraltar, which departed on 13 September 1941 and carried eight Martlet fighters. On 21 September, the convoy was attacked by a German Fw 200 Condor, which bombed the Walmer Castle, the rescue ship, and inflicted heavy damage. A Martlet from Audacity, probably flown by Sub-Lieutenant Eric Brown, shot the Condor down, Audacity's first air victory. Walmer Castle, however, was so badly damaged that she was scuttled by an escorting corvette. The convoy also lost four merchantmen to U-boat action, which underscored the vulnerability of Audacity to submarines without an anti-submarine aircraft complement. Despite all of these losses, the fighters from Audacity had earned their worth in their ability to fight off air threats.

Convoy HG 74 (October 1941)

Audacity then accompanied Convoy HG 74, leaving Gibraltar for the UK on 2 October and arriving at the Clyde on 17 October. This convoy was at less risk and Audacity’s fighters posed a significant enough deterrance to German aircraft. The uneventful transit was used to practise operations from the open flight deck, offering valuable experience for carrier aviation from a warship.Modified WACs were also used for both warfare and training.

Convoy OG 76 (October–November 1941)

Audacity's third operation was OG 76 from Liverpool to Gibraltar in late October 1941. Some remarkable success was enjoyed by this patrol, for its Martlets destroyed four Fw 200 Condors, a record for a single convoy escort. Sub Lieut Eric Brown had claimed 2 of these before he became known as the ‘Condor killer’. One Martlet was shot down by the enemy, but the elimination of four of the long-range bombers seriously disrupted German reconnaissance and bombing efforts. The victory designated Audacity as a high-priority target for the Kriegsmarine, which had received specific orders from U-boat chief Admiral Karl Dönitz to sink the aircraft carrier.

Convoy HG 76 (December 1941)

Her last mission was to escort Convoy HG 76 (originating from Gibraltar on 14 December 1941) from which she sailed with only four Martlets aboard due to earlier losses and maintenance. The convoy was heavily attacked by both Fw 200 Condors and a wolfpack of U-boats, such as U-131, U-434, and U-567. On December 17, U-131 was attacked with depth charges by a Martlet from Audacity, in company with gunfire from the escort destroyers HMS Exmoor, HMS Blankney, and HMS Stanley and the sloop HMS Stork, all taking part in the sinking. U-131's crew were made prisoners on Audacity, an unusual occurrence of a carrier capturing U-boat men.

On December 21, disaster struck. As Audacity was trying to extricate itself from the convoy, a merchant ship launched a gay “snowflake” flare and outlined the carrier against the sky. Kapitänleutnant Gerhard Bigalk in U-751 took advantage of this, and at 1,200 m, fired a spread of four torpedoes. The first torpedo struck Audacity’s engine room at about 20:37, with the ship beginning to go down by the stern. Two inboard torpedoes set fire to the aviation fuel holds, damaged the bow, and the ship sank after 70 minutes at 43°45′N 19°54′W, 500 miles off Cape Finisterre. Of the crew, 73 were lost, and survivors, including Eric Brown, were picked up by the corvettes Convolvulus, Marigold and Pentstemon. The convoy also suffered the loss of the destroyer HMS Stanley and two merchant ships, but 30 ships made it to safety, and three U-boats were sunk, a pyrrhic victory for the Allied side.

Contribution to Anti-Submarine Warfare

Audacity’s fighters were not fitted for anti-submarine patrols, but their presence compelled U-boats, which lacked true submerged speed, to spend most of their time below the surface, unable to shadow convoys. The destruction of U-131, with the help of a Martlet’s depth charges, proved the concept of carrier-based aircraft to support anti-submarine warfare, a role that subsequently growing escort carriers such as USS Bogue would take on with specialized ASW aircraft. The operations of Audacity proved the concept of coupled air and surface escort, which ultimately became a key to the success of the Allies in the Battle of the Atlantic.

Challenges and Limitations

Audacity's architecture was highly limiting in terms of its functionality. No hangar deck placed the aircraft at the mercy of salt spray and the elements, rendering the aircraft more difficult to maintain and less readily available for operations. Its lack of fighters (rarely as many as six to eight) severely limited it to low-intensity air operations. The slow, lightly armored ship was easy pickings for U-boats, as its sinking proved. And the emphasis placed on fighters and not ASW aircraft had made the convoys open to sub threats; something learned and is reflected in the designs of later escort carriers with mixed air wings.

It was a tough job on the carrier when the first of its kind was a half-built ship that lacked many facilities. This conversion, though novel, was hasty and resulted in compromises in structural strength and in armament. The Type 79B radar may have been revolutionary in 1939, but its performance for 1941 was old-hat; it gave very limited warning of fast-moving threats. These technical issues highlighted the fact that the use of Audacity was experimental, but this did not prevent it from having strategic significance.

Legacy and Impact

The short-lived service of HMS Audacity left an enduring mark on naval warfare. As the world's first escort carrier it had established that converted merchantmen could provide air cover for convoys, closing the Mid-Atlantic Gap and substantially reducing losses to U-boats and aircraft. Its effectiveness in shooting down Condors and its contribution to U-boat losses showed the importance of carrier-based fighters in convoy defence. What was learned from the experience of Audacity led to the development of subsequent escort carriers with hangars, elevators and ASW aircraft that were instrumental in achieving the Allied Ascendancy in the Battle of the Atlantic.

The loss of Audacity was a blow to morale, 18 but the safe arrival of most of the ships of Convoy HG 76 and destruction of three U-boats encouraged its use. The legacy of the ship was carried forward in the rapid acceleration of the escort carrier program, and ships such as HMS Nairana and USS Gambier Bay built upon Audacity’s ground breaking work. Its crew, including contemporaries such as Eric Brown, epitomised courage, and the ship’s service to the Allied war effort secured its position in naval history.

final thoughts

HMS Audacity was a WWII naval pioneer, having converted a captured German merchant ship into a revolutionary escort carrier in 1943. Its inconspicuous design, compromised by its merchant nature, was somewhat redeemed by its original use of fighter aircraft for convoy protection against air attack. Convoys OG 74, HG 74, OG 76 and HG 76 Audacity’s part in the Battle of the Atlantic, particularly in Convoys OG 74, HG 74, OG 76 and HG 76, illustrated her capacity to upset German plans and contribute to the downfall of aircraft, including several Fw 200 Condors, as well as U-boats. Although sunk by U-751 in December 1941, Audacity's influence as the Royal Navy's first escort carrier lived on, forming the basis for convoy defence tactics that contributed to the eventual Allied victory. Its tale is one of improvisation, heroism and tactical ingenuity in impossible circumstances.