Rising from the Depths: A Piece of the HMS Hood Rises Again With the Help of Pneumatics

The recovery of the ship’s bell from the wreckage of the HMS Hood is a stunning example of a practical use of pneumatics in wet environments. The pneumatic devices used in the recovery are highly specialized and were of the type supplied by companies like SMC Pneumatics USA (Orange Coast Pneumatics), a supplier of products manufactured by SMC Corporation of America.

The HMS Hood

The 40,000 ton HMS Hood, one of the largest and most powerful warships ever built, was commissioned in 1920. Shortly after the outbreak of World War II, the HMS Hood and the HMS Prince of Wales gave chase to the German battleship Bismarck, setting the stage for what was to be the last great naval engagement between battleships. The confrontation took place on May 21, 1941 in the Denmark Strait, between Greenland and Iceland.

When a shell from the Bismarck struck its munitions storage area, the pride of the Royal Navy exploded and sank, taking 1418 men with it to the bottom. There were but 3 survivors. Several days later, the Bismarck was attacked by the Royal Air Force and suffered a similar fate.

Sixty years later, the wreckage of the HMS Hood, including the ship’s bell, was located and photographed by Blue Water Recoveries. Upon receiving permission to retrieve the bell, Blue Water Recoveries returned to the site in 2012.

The Octopus, and the “Octo” ROV

Microsoft co-founder and philanthropist Paul Allen loaned his private yacht, the 414 foot Octopus, for the recovery effort. The Octopus has served as a party yacht, as a scientific exploration ship, and as a rescue vessel. On board the Octopus was a 5,000 lb remote-controlled submersible (ROV), dubbed the “Octo”.

The 2012 recovery effort was unsuccessful due to inclement weather. A second attempt, on 7 August, 2015, was successful.

Raising the Bell

The ROV was lowered to the seabed and its cameras enabled the operator to position the Octo to where it’s 4-jointed remotely controlled robotic arms could gently lift the bell from the ocean floor. Recovering the ship’s brass bell was no easy task, and the performance of pneumatics in wet environments would be tested, but the pneumatic devices performed magnificently. The bell was gently lifted from the ocean floor and slowly taken to the surface.

The bell will undergo a year of restoration, after which it will be reunited with the bell from the Prince of Wales at the National Museum of the Royal Navy.

As you can see, underwater operations can be challenging, especially at significant depths. High quality pneumatic parts, such as those we supply, are essential. They include such items as special tubing that can withstand and maintain the pressures vacuum pumps can generate, vacuum pads that will create a seal to enable an object to be moved or held in place, and finger grippers such as those that were used when lifting the Hood’s bell from the ocean floor and above the surface.

SMC Pneumatics USA, powered by Orange Coast Pneumatics Inc. (ocaire.com), is a National Elite distributor for the SMC Corporation of America. SMC offers 11,300 general pneumatics products, with over 560,000 variations, engineered to meet applications in every sector of the market, including pneumatics for wet environments. From Semiconductor to Automotive, Medical to Petroleum, SMC's products are designed to fit your unique requirements.