HMS Thetis

The HMS Thetis was a Group 1 Class T submarine that sank during sea trials on the 1st of June, 1939.

The following is an extract from Wikipedia :

Thetis was built by Cammell Laird in Birkenhead, England and launched on June 29, 1938. After completion, trials were delayed because the forward hydroplanes jammed, but eventually started in Liverpool Bay under Lieutenant-Commander Guy Bolus. Thetis left Birkenhead for Liverpool Bay to conduct her final diving trials, accompanied by the tug Grebecock. As well as her normal complement of 59 men she was carrying technical observers from Cammell Laird and other naval personnel, a total of 103 men. The first dive was attempted on June 1, 1939 at about 14:00. The submarine was too light to dive, so a survey of the water in the various tanks on board was made. One of the checks was whether the internal torpedo tubes were flooded.

Lieutenant Frederick Woods, the torpedo officer, opened the test cocks on the tubes. Unfortunately, the test cock on tube number 5 was blocked by some enamel paint so no water flowed out even though the bow cap was open. This combined with a confusing layout of the bow cap indicators - they were arranged in a vertical line with 5 at the bottom - 1,2,3,4,6, and then 5; and the shut position for tube 5 on the dial was in a different position to the other torpedo tubes - led to the inner door of the tube being opened. The inrush of water caused the bow of the submarine to sink to the seabed 150 feet below the surface.

An indicator buoy was released and smoke candle fired. By 1600 Grebecock was becoming concerned for the safety of Thetis and radioed the HMS Dolphin submarine base at Gosport. A search was immediately instigated.[2] Although the stern remained on the surface, only four crew escaped before the rest were overcome by carbon dioxide poisoning caused by the crowded conditions, the increased atmospheric pressure and a delay of 20 hours before the evacuation started. Ninety-nine lives were lost in the incident. In addition to the normal crew of 53, there were 26 Cammell Laird employees, another 9 naval officers, 4 Vickers-Armstrong employees and 2 caterers.


On a small road above Liverpool Bay, a 12 year old boy and his 10 year old best friend watched the saga unfold.

It was my dad, Arthur Weldon and his Cousin, Stanley Weldon who were going on holiday, travelling along the Mersey Estuary in a bus when the driver stopped.

Stan Weldon, who lives near Prescot, remembers that June day quite vividly :

In Liverpool Bay, HMS Thetis, was seen with her stern raised above the waterline, her nose buried in the sea bed.

Stan has told me that they could see a few boats sailing around the stern of the ship and lots of activity in the water and on the shoreline. It was an exciting and somewhat fascinating time for all the children on that bus, many of whom did not realize what history was happening before them.

The saga of this submarine did not end there, it was salvaged, renamed the HMS Thunderbolt and eventually was lost during valued service in World War Two.