Diving Fatality in a Submarine
by Greg Paul
Thanks to Australian Police Journal for allowing us to reprint this article.
Confused, unable to see, running out of air and desperately seeking a way out. Itâs hard to imagine what Julia Alexanderâs final conscious moments would have been. She was trapped underwater, inside the hull of an old scuttled submarine over 40 metres (135 feet down). The nightmare soon ended, however. It was one from which she would never wake.
Seven J class submarines were built in 1915 to 1916 for the Royal Navy during the first world war. At that time they were the fastest in the world, with a surface speed of 19 knots and a submerged speed of 10 knots. They had an endurance of 4000 miles on the surface, and 2000 miles whilst submerged. The J class subs were 84 metres long and had a crew of 44.
In 1919, Britain presented the Royal Australian Navy with six submarines and six destroyers which were no longer required. However, extremely high operating costs together with a huge post-war cut in the defence budget soon resulted in a decision to decommission and scrap the submarines. They were sold to a Melbourne salvage company in 1924 and all six J class submarines were eventually scuttled. Two became breakwaters, the J7 at Sandringham, and J3 at Swan Island. In 1926 the J1, J2, J4 and J5 were towed outside the Phillip Bay heads and sunk in the shipsâ graveyard. This is a deep water area with hundreds of scuttled and wrecked vessels.
The J2 settled in between 40 and 50 metres of water about three kilometres south of Point Lonsdale. In the process of sinking the J2, the hull was blown apart just in front of the conning tower. For this reason J2 is also known as the âBroken subâ. The break can give divers easy access to the inside of the submarine and has become popular with recreational divers who rediscovered its location in 1974. The shipsâ graveyard is now a favoured spot for underwater archaeologists and sport scuba divers.
Deep diving has its hazards. The amount of air consumed at a depth of 40 metres breathed at the same rate will be five times more than the amount used on the surface. The need to conserve air is the prime concern for scuba divers in deep water.
Another problem is that nitrogen in the pressurised air becomes narcotic. People are affected in various ways, similar to alcohol. The effects tend to increase proportionate to the depth, slowing mental activity, reaction time and creating a feeling of euphoria. Sometimes a diverâs judgement becomes seriously impaired.
The risk of decompression illness (the bends) is another serious problem for the deep diver. Air is around 80% nitrogen and 20% oxygen. Oxygen is used by the body, while nitrogen remains inert. Under increased pressure, the gases are absorbed into the body, elevating the levels within the system. When the diver ascends, the water pressure decreases so the concentrated gas begins to diffuse out of the system. If the pressure reduction is uncontrolled or sudden, the residual nitrogen forms bubbles within the bloodstream and tissues. The body literally fizzes internally, potentially causing serious medical problems or death. In order to avoid risking âthe bendsâ, divers have limitations of time that they can spend at various depths.
If the time is exceeded, additional time must be spent at shallower depths in order to decompress slowly. A dive to 40 metres limits the diver to only seven minutes (DCIEM decompression tables) before they have to leave the bottom, or face the need for decompression time.
Several recreational diving charter companies operate in the southern part of Port Phillip Bay, Victoria. On the morning of 10 January 1997, 12 wreck divers and two crew left the port of Queenscliff on board a commercial dive boat. The group headed for the wreck of the Courier, but radio contact with Point Lonsdale lighthouse revealed that a large container ship was approaching the site, so a decision was made to change location, and dive the nearby J2 (Broken sub), which was a similar depth, and away from shipping traffic.
Most of the group on board were very experienced divers, including several instructors and dive masters. Julia and Greg Alexander were both 28 years old and had been married for four and a half years. Both had completed their initial Open Water Diver Course before they married and then did Advanced, Deep Diver and Diver Rescue courses. Greg was training to become a diving instructor.
At 9.51am Julia and her dive buddy/husband descended the shot line to the bottom, which was a short distance from the wreck of the old submarine. Visibility was between one and two metres. The couple went to the aft end of the submarine. A large open hatch presented an invitation to enter the old sub where visibility was better because it was sheltered from the current. Greg entered the hatch and via hand signals, asked Julia if she would like to follow. She signalled âOKâ. The inside of the hull at this point was about two metres in diameter. The couple swam through the inside of the sub and maintained good buoyancy control which avoided disturbing the silt and obliterating visibility. They soon arrived at the broken section of the hull.
So far, the dive had gone well and they were still within their critical bottom time of seven minutes. However, to continue the dive inside the bow section of the submarine now was a critical decision.
The couple continued on, swimming through the hull, past the break, towards the bow. As they did so they passed two other divers travelling in the opposite direction whose movement stirred up the silt. The water clouded up and visibility deteriorated badly. Greg and Julia became disorientated; they could see each other, but little else. Greg swam to the nearest wall to feel his way out. At this point his dive computer gave the alarm signal telling them they had exceeded their bottom time for a no decompression dive. From that moment onward, swimming to the surface without a stop would risk decompression illness. The couple knew they didnât have enough air for a prolonged decompression stop. Greg took hold of Juliaâs hand and placed it on his tank valve behind his head, hoping to guide her out of the submarine.
The silt-filled water and the walls blended together, making it difficult to see the difference. The urgency of the diversâ movements compounded the problem. Lights were of little value in a non-transparent environment. Greg felt along the wall, and thought he came to an area he had seen before. It appeared to him that they were going the wrong way, so he changed direction. Ahead of him, Greg saw some light and headed for it, but on arriving at the break he realised Julia was not with him.
Greg had about a quarter of his air left. In a desperate attempt to find his wife, he swam back inside the hull to the area where they had turned around. The hazardous suspended silt had reduced the visibility to nil. He collided with something that dislodged his mouthpiece and mask. Precious air and time were wasted as he grabbed his spare regulator and cleared his mask. He went back to the break and still couldnât see Julia.
Greg now faced a heart wrenching dilemma. He was way over bottom time, critically short of air, and 40 metres from the surface. Did Julia get out? If he continued searching inside the sub he would risk certain death.
Greg made a rapid ascent to the surface – arriving 19 minutes after the start of his dive. His dive computer later showed that he had missed 27 minutes of decompression stoppages. Nitrogen had accumulated to dangerous levels, and his body had rapidly decompressed. He was in dire need of help. As the other divers eventually surfaced Greg frantically told them what had occurred. It was clear that Julia had not surfaced and was probably still inside the submarine. Time was critical. She would either be on the verge of running out of air, or had already run out. For a chance of saving her life, however slim, it was a now or never situation.
See the December/January issue for part two – the rescue attempt.