Deeper into the Darkness. Rod MacDonald

Чтение книги онлайн.

Читать онлайн книгу Deeper into the Darkness - Rod MacDonald страница 19

Deeper into the Darkness - Rod MacDonald

Скачать книгу

of Everest were members, Thor Heyerdahl in Kontiki – the list of firsts for members goes on and on.

      At The Explorers Club HQ in New York, there is a humble granite plaque which reads:

      WORLD CENTER FOR EXPLORATION

First to the North Pole1909
First to the South Pole1911
First to the summit of Mt Everest1953
First to the deepest point in the ocean1960
First to the surface of the Moon1969

      Underneath the last entry there is a space – waiting for the first manned Mars landing.

      Since 1918, whenever the Explorers Club believes that an expedition is going to be of scientific or special merit it awards an Explorers Club flag, which is then carried on the expedition. There are some 220 flags in total, and the flags are reused on successive expeditions in the field. Explorers Club flags have been carried to all the earth’s continents, as well as to the deepest parts of the sea and the highest places on the land – and to the moon.

      As at the date of my expedition, 850 explorers had carried the flag on 1,450 expeditions. A select few of the 222 flags have been retired and framed for display at the Club House in New York. These include the flags carried by Thor Heyerdahl on his raft Kontiki as he sailed across the Pacific, and the miniature flags carried aboard Apollo 8 and 15. Some special flags are of particular historic importance, such as the flag carried aboard Apollo 11 by Neil Armstrong and Buzz Aldrin to the surface of the moon.

      The Explorers Club declared our Hampshire expedition to be a Flagged Expedition due to the historic importance of the shipwreck – and two weeks before the expedition was due to begin, an airmail package arrived with Flag #192 and the paperwork to go along with it, which included a list of the previous expeditions this very flag had been carried on.

Amos Burg1968 Alaska Rivers Expedition
Dr. George V.B. Cochran1974 North Baffin-Bylot Expedition
Dr. George V.B. Cochran1972 Baffinland Arctic-Alpine Expedition
Dr. George V.B. Cochran1973 Baffin-Kingnait Expedition
Peter Byrne1975 Nepal Himalayan – Terai Mammals
Ralph Lenton1970 Mt Ararat Expedition
Dr. I. Drummond Rennie1973 American Dhaulagiri Expedition
William Isherwood1971 Glaciological Survey
Bob Sparks1975 Trans-Atlantic Solo Balloon Crossing
Bob Sparks1976 Trans-Atlantic Balloon Flight.

      The flag had been lost on expedition in the late 1970s – but had recently been found and returned to the Explorers Club shortly before my expedition. After a break of some 40 years, it was going on expedition again.

      Our dates were now set in stone – and with all the acceptances now in from our team, we now had major commitments being made. Paul Haynes, in his capacity of dive safety officer, created a thorough 40-page Dive Brief, and this was emailed out to all the team members six months before the exped. This covered the basics of our planned diving methodology, such as the standardisation of rebreather trimix diluent gas of 15/50 across the team. This provided an oxygen partial pressure (PO2) of 1.2 bar at the deepest depth anticipated of 70 metres, and facilitated an effective rebreather diluent flush without the safety implications of using a ‘lean’ hypoxic gas, where a diver could black out. At the maximum depth of 70 metres, this trimix mixture would give divers an equivalent narcotic depth (END) of 25 metres. This means that at 70 metres the divers would only be experiencing the same nitrogen narcosis as a diver diving on air at 25 metres, next to negligible.

      Each diver had to carry sufficient open-circuit bailout gas to independently support a full open-circuit decompression profile in the event of a catastrophic failure of the primary life support rebreather. As a minimum, divers were required to carry an 11-litre cylinder of bailout 15/50 bottom gas under their left arm and an 11-litre cylinder of EAN 60 deco gas on their right side.

img26.jpg

      A diver tag in/out system was used for all dives during the expedition with named tags for all divers being supplied. The tags were clipped to a brass ring where the transfer line from the trapeze connected into the fixed downline. (Author’s collection )

      We would be using a decompression trapeze with horizontal bars at 6, 9 and 12 metres, and ropes leading up at either side to two large red buoys that would float it. We intended to lay two fixed downlines, one at the bow of the wreck and one at the stern. The trapeze would be secured to the bow or stern downline by a transfer line on a daily basis. Extra cylinders of bailout gas would be clipped to the downline and the trapeze in case of emergency.

      A diver ‘down / up’ logging system using named tags was employed to monitor who had left bottom and ascended to the trapeze. Each diver was given a stainless steel shackle with a colour-coded plastic name tag on it, with their name. Individual divers clipped their named tags to a brass ring in the transfer line at a depth of 30 metres on the descent. Divers would remove their tag from the ring as they ascended at the end of the dive and moved along the transfer line to the trapeze for decompression. The last diving pair ascending would disconnect the trapeze from the downline before continuing their ascent up the trapeze transfer line. All 12 divers would then begin to drift with the current, which would be picking up as slack water passed, as they slowly ascended through the various levels of their decompression stops.

      Once all 12 divers were on the trapeze and we had disconnected and begun to drift, the procedure would be that a single 6-foot-tall red delayed surface marker buoy (DSMB) would be sent up. If for any reason there was a separation event, and divers failed to return to the downline, the team would wait 20 minutes to give the lost divers a chance of finding their way back to the downline. If the divers had not arrived at the deco station by that time, the trapeze would be disconnected from the downline. With the tide picking up after slack water, it would be impossible for all the divers to carry out two hours of decompression stops with the trapeze still connected to the downline. It would be swept horizontal and possibly up to the surface. Once the trapeze was unclipped and was drifting with the current, the divers would feel that they were in comfortable stationary water – even though the whole mass of water they were suspended in was racing across the seabed at 1–2 knots.

      If we had to disconnect with divers still on the wreck or doing a free ascent away from the downline, then we would send up a yellow DSMB. That would be the signal to the skipper topside that there had been a separation event and that he should keep his eyes peeled for DSMBs from free-drifting divers. With such a group of seasoned deep divers, each had lots of experience of carrying out free ascents under their own DSMB. It wouldn’t be an alarming situation; we just wanted a way of telling the skipper topside that divers were separated and that he should look out for their DSMBs, as well as following the trapeze.

      To keep the divers together in a loose single group on the trapeze for deco, we restricted bottom time to 35 minutes.

      All divers were required to carry a minimum of one red DSMB with their first name or initials written in large black letters on the top of it, together with a whistle, hi-vis flag and yellow DSMB for emergency signalling. This was no place to be separated from the dive boat and not be seen.

      The team would arrive in Orkney on Saturday 28 May and load kit onto the Huskyan, and once everyone was sorted out with cylinders filled and analysed, scrubbers filled with sofnalime, rebreathers all prepped and set up, we would have a briefing that night. Diving would start the next day, Sunday 29 May, with two shakedown dives on the deepest German World War I battleship in Scapa Flow, the upturned SMS Markgraf in 45 metres. The early morning dive would be a simple personal shakedown dive to reveal any problems that might have occurred in transit and so that people could make sure they were happy with their kit. The afternoon dive would be a full dress-rehearsal, deploying the trapeze, adding the extra bailout

Скачать книгу