Initially no emergency bailout facility was available, but at a later stage in the development of this self contained unit a bailout cylinder was added beneath the counter lung. Duration of a breathable gas supply as a result of these modifications within the new unit was hence increased to 6 hours. Although an understanding of the hazards of breathing pure oxygen at depth were becoming apparent, at the time the use of mixed gas was at the experimental stage.

By now with the method of delivering a substantial warhead in the pipeline and a workable method of breathing, it remained for a suitable dress to be found that was both durable for the task in hand, that completely sealed off the operator from the elements but would be flexible enough not to impede his movements. Siebe Gorman at the time were not producing lightweight diving apparel specifically for warfare and the Standard Diving Dress used with helmet gear, as it stood, was totally impractical. It was the brainchild of Commander Geoffrey Sladen to come up with a solution. Working with Siebes at their Tolworth factory in partnership with the Admiralty Experimental Diving Unit he designed what was to become known as the Sladen suit.

The Sladen Suit

Showing the entry skirt folded just below the divers midriff.

Made of a lightweight rubberised twill laminate similar to that used for the Standard Diving Dress (produced by Macintosh & Son,) it was inflexible to stretch so the design incorporated a modified midriff consisting of a tubular skirt at the front to afford entry and exit. The skirt was made watertight by folding it concertina fashion and then clamping the folds between two tinned brass rectangular plates bolted tight at each end using wing nuts. The neck was tailored to incorporate a moulded rubber/twill hood with a manually operated exhaust valve fixed at the crown and finally, as mentioned earlier, a full facemask from the "Salvus" set was adhered to the front of the hood to make it watertight but retaining the web adjustment straps for individual fit. Other modifications to this somewhat bizarre and somewhat cumbersome dress were soon to follow including a rectangular Perspex visor hinged at the top to enable the use of binoculars for beach reconnaissance operations. The ordeal of dressing and the discomfort of wearing it in the hot confines of a submarine where sweat completely drenched the wearer prior to a cold exit later earned it the nickname "clammy death."

Chariot crew in full attire prior to mounting up for a training exercise

Both crewmembers are wearing early versions of the Sladen suit and hood assembly.
The entry skirts can be seen with their clamp plates in place just below the counter lung.

As with all hazardous operations carrying a high risk all men were chosen from volunteers. Initial training was extremely arduous with an emphasis on swimming, running and full pack marching over heavy terrain as part of the escape and evasion strategy most were to become familiar with in future operations. Those not up to both the physical and mental conditions were soon weeded out and returned to their original units. All volunteers were sent through the wet pot at Siebe Gorman's in Tolworth where they were subjected to oxygen tolerance tests at depth. Here they experienced first hand the hazards of oxygen poisoning and its associated conditions that were to become termed under the singular nickname "Oxygen Pete". Unknown to them at the time was that little was known regarding the physiological effects of oxygen both as a partial pressure in air or breathed in pure form under increased pressure and its toxicity when metabolised at high concentrations. As mentioned in the previous chapter experiments with mixed gas such as Nitrox was very much in it's infancy and Helium as a by product of Hydrogen was very difficult to obtain in Britain at the time. Having survived their experiences as Siebe's guinea pigs, they then went on to train as divers using the new Sladen suit and closed circuit breathing apparatus.

Hood and mask assembly

Showing completely integrated hood, mask and visor assembly. 
One major problem with this unit was the difficulty in looking down at the controls and if the hose broke or leaked you had serious problems.

Familiarization and initial training in the use of the human torpedo was to take place first in Loch Erinsort and finally in the more suitable depths of Loch Cairnbawn, Scotland. It was here that the characteristics of the craft were to earn it the nickname of "Jeep" because of the noise the props made when its tail came out of water, or "Cassidy" after the American Cowboy because of its tendency to porpoise if the trim was upset. This together with the rudiments of surface and sub-surface navigation and the art of stealth in attacking the target vessel through harbour defences, mostly under night time conditions, honed the men into small unique units. Bringing it all together in time for an attack after approval from the Admiralty was the beginning of economic warfare. It had considerable potential and the machines were cheap to produce. Although airborne delivery methods were tried using a Sunderland Flying Boat they proved unsuccessful. Submarines were finally used as a primary means of delivery and pickup, and few men were needed to mount an operation that had the capability of a great deal of destruction if the operation was successful. If not, little was lost in the effort.

First Hand Experience

"Cassidy" had now become an official weapon upon which a new breed of warrior would ride to war, and from whence it became renowned as the "chariot".

It is at this point that the next part of the story unfolds. Len Berey at the time was a young Petty Officer serving with the 12th submarine flotilla after joining the ranks of those few odd fellows who always seem to leap into the unknown by "volunteering for something". In Len's case it was to be trained in submersible operations in answer to the success of the Italian underwater attack against the Valiant and Queen Elizabeth at Alexandria, Egypt. He was among the first group to be selected for training in this newly formed arm as human torpedo operators under the command of Geoff Sladen and "Tiny" Fell. From the early days as a Guinea pig at Siebe Gorman to becoming a fully-fledged charioteer Len was to be involved in a number of operations within the Mediterranean arena. One of which was the Tripoli raid in North Africa, the aim of which was to attack enemy vessels that had the potential for blocking Tripoli Harbour (Libya) against the advancing Eighth Army.

Len takes up the story; Aboard the submarine THUNDERBOLT we had been waiting below the surface for two hours hoping that an enemy E. Boat between our position and the shoreline would move off. The RAF had already mounted a diversionary raid and had long gone by now. Time was running short and with the E. Boat staying on station the Captain made the final decision to mount the operation and to surface to casing level with only the conning tower visible. After exiting via the conning tower, we proceeded to don our diving gear on the casing while the crew pulled our machines out of their containers. The crew then retreated closing all hatches behind them ready for a quick dive after we had left. The scene was now of total loneliness, the casing was completely devoid of life except for four figures dressed in grotesque looking diving suits. We could see the E. Boat lying toward the shore but as there was no sign of activity presumably he had not seen us as it was an extremely dark night. Except for the stars, he was not likely to. I personally felt very vulnerable and apprehensive about the unknown and my imagination was beginning to run wild conjuring up all sorts of dangers. These thoughts were only fleeting and before I knew what was happening the sub began to submerge beneath us. If you can imagine the situation standing on the casing of a submerging submarine with air and water hissing and boiling all around you on a pitch-dark night wondering if you will ever get back. I could not dismiss the situation lightly and wondered what on earth I had got myself into. With the presence of the German E. Boat nearby and surrounded by cascades of swirling water from the subs vents. You feel as big as a barn door. At this point I noticed that the chariots were floating off the deck as the sub sank below the surface and suddenly became aware that I was being dragged down with it. The valve on my breathing gear had caught under the subs jumping wire (this is the wire cable that runs from fore and aft over the conning tower, it is designed to assist a submarine through anti submarine nets that guard the mouth of harbours). Luckily, I had the strength to pull myself free, but in so doing the oxygen valve was knocked on and I had to spit out my mouthpiece to prevent my lungs from over purging, my suit began to inflate rapidly while I ballooned upwards with air venting from the cuffs and hood valve. I broke surface and struggled to turn the offending valve off before returning to normal, all this probably happened in a matter of seconds. After breaking the surface close to my machine I proceeded to clamber aboard where my number one, Geoff Larkin, sat astride waiting for me to sort myself out. We were to find out later that the subs jump wire had also damaged our chariots hydroplane. Meanwhile there was no sign of Lt. Stevens or Chief E.R.A. Buxton, the other pair. This became a common feature of all future launches .We never saw our colleagues again till after an operation but, owing to the number of losses, that didn't often happen. We were now under way toward the target some five miles off at a speed of 2.5 knots. The normal procedure in the cruise is for the number two operator to keep his head down below the surface while the number one up front steers the craft with his head just above. Shortly after we had left the sub I became aware of a thumping noise, sound carries well under water, on lifting my head above the surface I could see a tug bearing down on us. I gave Geoff a thump on the back and indicated the danger to which he rapidly responded by taking the machine down. The tug passed overhead and the noise seemed to be inside my skull. Something I will always remember. Continuing with our journey it became apparent to me that Geoff was having some difficulty in controlling the stability of our machine and after some three hours I lifted my head to see the coastline ahead. Geoff saw the situation as grave with little response from the machine in diving mode and the chance for any successful attack by the other pair could not be jeopardised by our own predicament. Our attack had to be aborted. I had by now virtually exhausted my oxygen supply owing to the earlier problem and was having difficulty breathing, opening the main valve made very little difference and by this time we were on the beach where I immediately opened the surface valve on my mouthpiece. Geoff staggered ashore completely exhausted after toiling with the machine throughout the run. The next thing was to get rid of the machine. With a slight swell running I had great difficulty in turning it out to sea with one ton of machine pushing me onto some rocks and every time I went under I got a mouth full of water. However, I eventually manoeuvred the machine out to sea after setting the pump to flood the tanks, setting the speed control to ahead and setting the charge to go off some hours later. After divesting ourselves of the diving gear it was time to assess our situation, between the rocky outcrops we seemed to have landed on a small sandy beach with a 10ft. bank on the landward side with some barbed wire defences around what must have been a camp as we could hear voices.

Capture, escape and evasion were soon to become our way of life in these situations. But that’s another story.

Both Len and Geoff Larkin eventually made their way to Cairo courtesy of the first contingent of the Eighth Army to reach Tripoli. They were finally shipped back to base in Malta from which further operations were mounted including their last operational sortie against the German occupied harbour of La Spezia. In September of 1943 Italy saw its past political misdemeanours, recognized its losses and surrendered to the Allies while declaring war on Germany. Joint operations were now to include both Italian ground forces with the Italian Navy joining up within the Mediterranean theatre, including special operations. Thus utilising the knowledge and experience of the gamma frogmen of the Italian Navies 10th. Light Flotilla, or Decima Mas, who had in the past carried out some highly successful raids against the British Mediterranean Fleet. In March 1944 Len Berey along with his colleagues were charged to mount one final operation to fight alongside their Italian counterparts. This was to be operation 'Principal', the attack against two Italian Naval vessels within the harbour of La Spezia on the west coast of Italy, now held by the Germans. It was an ironic situation for the men of the 10th Light Flotilla who were about to destroy some of their own fleet. The operation was to utilise two Italian Navy Torpedo Boats to deliver two chariot teams to within reach of the harbour wall and to drop off a team of Italian gamma frogmen to swim in and place limpet charges. The targets were two cruisers, the Bolzano and the Goritza. Of the two Chariot teams, Len and his number two Ken Lawrence were once again to be confronted with an aborted mission owing to faults with their machine. The second team along with the gamma boys did get through with the result that the Bolzano was sunk and the Goritza was put out of service for the rest of the war. Len and his colleague Ken Lawrence were left with a very long walk home but, unknown to Len the route back was to become an adventure on his part fighting alongside the local partisans for a brief period. For his part in the attack on La Spezia Len received the Distinguished Service Medal for gallantry.

A Tribute and a Trial

The Underwater Heritage Trust was the brainchild of Robert Hobson whose father was himself involved with chariot operations as a Commanding Officer. Initially set up by Robert to commemorate all those involved in chariot operations during the last war the Underwater Heritage Trust now covers all aspects of underwater warfare to which many gave their lives. Because of the very nature of their work, even today certain aspects are rarely known about outside of military circles. Robert has over the years combined with the help of those very few men involved that are still alive, both Italian and British, amassed a considerable amount of knowledge and information on the subject.

Continue to part 3