HMS VOLTAIRE

HMS Voltaire : The World War II Armed Merchant Cruiser

The Royal Navy armed merchant cruiser (AMC) HMS Voltaire had a brief but active life in the Second World War Battle of the Atlantic. Launched in 1923 as the passenger liner Voltaire for the Lamport & Holt Line, she was requisitioned by the Admiralty in 1939 and converted to a merchant raider to hunt down German commerce raiders and U-boats that threatened Allied convoys. Its career, from 1939 until it was torpedoed in April 1941, was typical of the Royal Navy’s dependence on converted merchantmen to increase its escort forces in the early years of the war. Written off as belonging to a bygone era of warships in the course of the 20th century, Voltaire’s role in convoy protection emphasized the extreme measures to which warring navies had to go to safeguard critical supply routes. This piece describes the construction of the Voltaire class, its features and the events of WW2 in which Voltaire took part, including meeting its end with German raider Thor, using accounts of the time to bring to light its role in naval history.

Design of HMS Voltaire

Origins and Conversion

HMS Voltaire was converted from a liner built for Lamport & Holt Ltd., by Workman, Clark & Co., Belfast, which travelled as a passenger liner from 1923. Constructed for the New York – South America service, the vessel was intended to be used for transporting passengers and freight, providing five holds for refrigerated and general cargo, and having accommodations for three hundred first class, one hundred fifty second class, and two hundred thirty third class passengers. The ship was 465 feet (141.7 m) long overall, had a beam of 59 feet (18.0 m) and a draught of 30 feet (9.1 m) and a displacement of 13,245 long tons (13,455 t), drawing on a pair of quadruple-expansion steam engines driving two screws to achieve a maximum speed of 14.5 knots (26.9 km/h; 16.7 mph). This speed was satisfactory for commercial service, but marginal for war time naval operations.

On 27 October 1939 Voltaire was requisitioned by the Admiralty and converted to an armed merchant cruiser at Wallsend. The conversion prepared the ship for duties escorting convoys and patrolling, upgrading it to a total of eight 6-inch naval guns taken from older warships and two 3 inch anti-aircraft guns, at least one of these being a dedicated anti-aircraft mounting. The conversion would keep the vessel's merchant hull and drive train, and very little armor was added for practical (time also being in short supply) but mostly economic reasons. Her crew amounted to some 269 including naval and merchant seamen and gunners trained to operate the obsolete weapons. The radar capability of Voltaire would be limited, probably based on a basic Type 286 air warning radar (25–40 miles range) which would be adequate for detecting aircraft, but less useful against surface threats.

Technical Specifications

Voltaire as a warship was always a compromised human contruction between commercial roots and naval needs. Its weapon system was geared to fighting enemy commerce raiders and aircraft, and though its six-inch guns were of World War I vintage and were long obsolete by 1941 standards. These 3-inch guns offered little effective defense against the modern Luftwaffe bombers such as the Focke-Wulf Fw 200 Condor. The ship’s steam engines, though reliable, limited its speed, exposing it to faster German raiders such as the Thor, capable of making eighteen knots. The ship's minimal armour left her vulnerable to gunfire and torpedoes, a common deficiency of AMCs that were converted from linares.

Capable as the ship’s merchant design was, the large passenger areas, as such it was then, personally refashioned for naval purposes, including crew quarters and shell stowage, were not combat-efficient. 91 The lack of watertight compartments and damage control systems, which were standard on specialized warships, also eroded the vessel's ability to survive. Despite these drawbacks, Voltaire, by virtue of her size and armament, had been a significant player in convoy escorts, able to discourage lesser raiders and reassure merchant crews.

Design Limitations

Voltaire's architecture bore the limitations common to such civilian-to-military conversions. Its slow speed left it unable to flee or chase down faster opponents, and the obsolete guns had a lower range and lacked fire control that was comparable to that of other contemporary naval artillery. Its minimal anti-aircraft armament was simply insufficient against fighter planes travelling at high speed, the lack of armour made the ship vulnerable to being shot to pieces, as was to be witnessed in its last battle. The crew fought under demanding conditions armed only with an unarmored ship designed for short combat operations, handicapped by limited radar and commo capabilities, severely limiting situational awareness. These shortages highlighted the AMC's ad hoc nature, designed as temporary escorts until more effective escorts became available later in the war.

What Made HMS Voltaire Special

Service as an armed merchant cruiser

HMS Voltaire served in a class of approximately fifty-six AO ships that were pressed into service by the Royal Navy during World War II at a time when destroyers and cruisers were in short supply and when the AO and AK types provided the economic and ballast support required for opening the conflict. Background AMCs were raspurposed liners and cargo ships with added naval guns to patrol trade routes, escort convoys, and take out the enemy merchant vessels. Voltaire’s duties were to protect Atlantic convoys from German commerce raiders, like auxiliary cruisers such as Thor, and to enforce blockades by searching neutral shipping for contraband. Large and well armed, it had an imposing look, discouraging smaller raiders, and giving the merchant convoys a “ship” to look at.

What makes Voltaire unique is that it went through several jobs before it landed on its AMC service. Originally requisitioned as a troopship, she spent time under the designation of an accommodation ship at Scapa Flow before being converted into the ship designed for combat. This flexibility showed the adaptability of the Royal Navy to utilise civilian vessels for differing warlike purposes. Voltaire’s commission to far-flung stations, including the Caribbean and West Africa, also underscored its strategic role in policing far-flung trade routes threatened by German raiders.

Strategic Importance

Voltaire’s participation in the Battle of the Atlantic was just one part of a campaign to secure Britain’s supply lines, which were crucial to sustaining the war effort. By 1941, German U-boats and commerce raiders had sent to the bottom thousands of tons of Allied shipping, with vital supplies of food and material at risk. Ship NameRunner HX 59Runner HX 45Runner HX 50Protection Provided by ConvoyA vessel that provided anti-aircraft protection for a convoy, that was in addition to the escorts listed.Location In TableGrand Total 1041Separately the great French statesman Voltaire, the last of the V class, served on several convoys such as HX 59, HX 45, HX 50. "\" A \" gun positioned aft of the bridge level with the cruiser building. It patrolled the central Atlantic near the Cape Verde Islands to deter raiders such as Thor, which preyed on vulnerable merchant vessels. The vessel's ability to serve independently in a patrol capacity meant the vessel could project the Royal Navy's power farther afield as modern warships were in short supply.

Psychological and Propaganda Value

The psychological effect among the Allies and Germans of Voltaire as an AMC is touched on above. The presence of an armed cruiser on Allied merchant crews bestowed a sense of security from the constant menace of raiders and U-boats. To the Germans, AMCs such as Voltaire were high value targets because by destroying them you disrupted convoy defence and bolstered Kriegsmarine morale. Voltaire was to the Corvettes, but Voltaire did not reach Saint-Nazaire German propaganda exploited the victory, yet the Kriegsmarine kept Thor’s identity secret so that the raider would remain a mystery ship. The loss of Voltaire, though a setback, hinted at the high stakes of the Battle of the Atlantic, where even outdated ships like her played a critical role in keeping open Allied lifelines.

Key Roles in Battles

The Battle of the Atlantic

HMS Voltaire is best known for its action in the Battle of the Atlantic, the protracted naval campaign to protect Allied shipping from the German Kriegsmarine U-boats and commerce raiders. She served under Western Approaches Command and later in the Americas and West Indies Station, escorting convoys between Halifax, Nova Scotia, and the United Kingdom, and patrolling the Central Atlantic to intercept raiders. Service On 23 August 1940, Frobisher went to sea to begin operations with the Halifax Escort Force, including Convoys HX 59, HX 45, and HX 50 during the rest of 1940 and a fatal patrol in April 1941 which resulted in a death on board while engaging the German raider Thor.

Convoy HX 59

The first significant war duty of the Voltaire was to escort Convoy HX 59 from Halifax to the Clyde in July 1940. Commanded by Captain (Retired) Claude L. Bate, DSO, RN, Voltaire was in company of destroyers HMCS Saguenay and HMCS Ottawa. The convoy dispersed in face of fog, and several ships, the Vestland, Kathariotisa and Tautra included, fell behind and made their way to the enemy independently. Voltaire gave anti-aircraft protection and surface raider deterrent, detaching from Voltaire on August 4, 1940 at position 50°04'N, 18°22'W to return to Halifax. There were no losses to enemy action and the convoy eventually reached its destination, a clear indication that Voltaire could exercise the control and protection it was required to provide to merchant ships during challenging circumstances.

Convoy HX 45

In May 1940, Voltaire led Convoy HX 45 from Halifax, in company with HMCS Saguenay. Fog was again the cause of stragglers, Manoula late at Liverpool and Senta at Belfast. Voltaire was to serve as anti-aircraft and anti-surface defense; it could clear deck using its six-inch guns to discourage any raiders. Convoy BHX 45 from Bermuda joined the convoy on 29 May, and Voltaire stayed with the convoy until the beginning of June to see it safely through the area. The lack of enemy action during this convoy demonstrated the deterrent effect of Voltaire, as German raiders refused to attack a strongly escorted convoy.

Convoy HX 50

Voltaire escorted Convoy HX 50 with auxiliaries HMCS Acadia and HMCS French in June 1940. The merchant ship Arona was disabled by mechanical problems and fell out of convoy, but reached her destination alone. Defensive armament and radar of Voltaire added to its own bodyguard and Convoy BHX 50 from Bermuda joined the convoy 19 June. No losses were taken, indicating that the mere presence of Voltaire was sufficient to deter attacks, albeit its slow speed and short radar range made it difficult to find or engage distant targets.

Action of April 4, 1941

The last and most important action in Voltaire’s life took place on the 4th of April 1941, while patrolling to the west of Cape Verde Islands around nine hundred miles from those islands. As a part of Selkirk Force, commanded by Acting Captain James A.P. Blackburn, Voltaire was on the search for German commerce raiders, she had recently refitted at Saint John, New Brunswick, and was working from Trinidad and Freetown, Sierra Leone. Unknown to the British, the German raider Thor (Ship 10) was also in the area, disguised as a Greek freighter.

At 06:15, the lookouts of Thor reported smoke on the horizon and identified Voltaire as a potential target. At first taking the vessel for a neutral passenger ship, Kähler approached. Voltaire, being under the impression that Thor was a light freighter, came alongside for identification and so indicated. At 06:45, 9,000 yd (8,200 m) separating the ships, Kähler hoisted the Kriegsmarine battle ensign and fired a shot across Voltaire's bow as a warning. Voltaire opened fire in return, then the latter revealed itself as an AMC, but Thor’s opening salvo of four 150mm shells hit the radio room and fire-control system, crippling the Voltaire’s ability to signal for help or control her guns.

The engagement was one-sided. Being fitted with more modern 150mm guns, Thor’s guns out-ranged and out classed Voltaire’s obsolete six-inch guns, while also having problems with over heating and firing too quickly. Within minutes, Voltaire was on fire; its boats were destroyed and the ship was heeled over seriously. White flags were raised — a sign of surrender, but too late for the toll was catastrophic. Kähler swung Thor around and brought her in closer, lowering lifeboats which then saved survivors as Voltaire went down stern-first. For next five hours Thor saved Captain Blackburn and one hundred ninety-six crew member (the rest were later repatriated) and was able to give details to the Admiralty of the encounter. Position Approximately 14°30'N, 40°30'W, 72 of crew lost, which demonstrated the vulnerability of converted armed merchant ships, when compared to real raiders.

Challenges and Limitations

The design and operational limitations of Voltaire stunted its force effectiveness. With its slow speed of fourteen and a half knots, it was an easy target for such faster raiders as Thor, which could choose the range at which it fought. The guns were obsolete six-inch guns and the fire-control was poorly functioning, and the ship's light antiaircraft guns was not enough for an effective defense against air attack (though no such attack on the battleship took place during its service). The absence of armor or any watertight compartments resulted in gun and torpedo hits being extremely lethal, as evidenced by the ship's quick sinking.

Operating in extreme conditions, the crew used a ship not constructed for war. The conversion, which also gave Voltaire naval guns, didn’t fix structural weaknesses or include modern radar, sonar or communications systems. The use of visual recognition, seen during the Thor engagement, left Voltaire vulnerable to miscalculations, as each side initially misjudged the other to be neutral. These difficulties highlighted that AMCs were a temporary expedient pending the arrival of destroyers and escort carriers.

Legacy and Impact

The brief career of HMS Voltaire had a profound impact on the way in which the Royal Nay came to understand convoy protection. Her work in the escorting of Convoys HX 59, HX 45, and HX 50 showed the value that AMCs played in keeping up U-boat attacks and holding convoys together, especially in the early years when there were not enough modern escorts available. The loss of Persia to Thor demonstrated the shortcomings of conversion liners, and the Admiralty preferred that future operations be conducted with purpose-built warships, and escort carriers such as HMS Audacity. The returning survivors repatriated from Voltaire contributed useful information on raider tactics, which was influential in developing anti-raider strategies.

The loss of Voltaire was a graphic lesson in the high stakes of the Battle of the Atlantic. The seventy-two crew who had died in the sinking, together with the one hundred ninety-seven who survived, became a symbol of the human cost of naval warfare and the courage of men who had fast-served on a flimsy ship. Though the encounter resulted in defeat, it marked a significant stage in the Royal Navy’s development of successful tactics, the paramount importance of fast escorts with adequate armament and an effective radar system. Service like Voltaires, as brief as it was, was a key part of the wider mission to keep Allied supply lines running that in turn kept the Allies in the war and eventually on the offensive along the lines of D-Day.

final thoughts

HMS Voltaire may not have been perfect, but she was a key part of the Royal Navy’s contribution to the early years of the Battle of the Atlantic which began with the Second World War. Originally a 1923 passenger liner, she was rushed into service between the two World Wars as an armed merchant cruiser and because of her obsolete armament and no armour was ill prepared for war other than being fast. As for the battleships’ role, its performance at Convoy HX 59, HX 45 and HX 50 in terms of scaring off attackers, and its loss to German raider Thor for 4 April 1941, would indicate the limits to which such conversions could be effective. The service of the Voltaire had demonstrated the capability of the Royal Navy of effectively employing its commercial ships to satisfy wartime needs and paved the way for more advanced convoy systems. Its significance is in the impact it had on the struggle that Allied convoys made through to life and the lessons learned from its sinking that would influence the course of naval warfare in a key theater of war.