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In the most recent field research work on the St Mikael in 1997 and 1998, T/A Anneli, a vessel owned and renovated by the Maritime Museum of Finland, served as the primary support ship for the divers. The Anneli is a former fairway inspection vessel M-101 of the Finnish Maritime Administration. The vessel is approximately 15 metres long. Since the accommodation and deck facilities on board the Anneli are limited, two support vessels are required at the site. The other support vessel in the St Mikael Project has been the Deko I, which has served as the accommodation and service vessel for the divers. The Deko I is owned by Diving Club H2O and its divers. The ship approximately 17 metres long has been converted into a diving support ship from a carrier.
Each support ship has 190 l/min, 200/300 bar compressors for air supply for the divers, aggregates for power generation, auxiliary boats and other equipment required by diving. The 1998 St Mikael expedition also used a Rigid Inflatable Boat (RIB) owned by the Maritime Museum and one owned by the divers of H2O. RIBs are very practical in surface manoeuvres such as in assisting the support ships to moor to the buoys. RIBs also turned out to be very handy tools in the constant traffic between the support ships and the island of Borstö and in the diving operations.
The equipment used on the St Mikael in 1997 and 1998 included, alongside diving equipment, a SuperHi8mm video camera system with lighting, underwater cameras, divers' cable telephones and wireless surface and underwater telephone units. The measuring tools comprised ordinary tape measures, plumb lines and plumbs for inclination and other measurements used for creating the measurement system. Various types of drawing tools and fasteners were naturally used also. The lifting work utilised padded plastic boxes with lid and control and lifting ropes as well as stroboscopes.
The diving equipment used during the last two expeditions represented two types of self-sufficient systems. The divers had systems developed for so-called cave diving techniques with nitrox gases and AGA Divator equipment with full-face masks and telephones. The common feature for the two systems in the St Mikael Project was the use of two regulator first stagespressure reducer valves with backup systems. In principle, a diver had to have at least 4,000 litres of air for each dive and a proper backup system. Since the St Mikael is a particularly dark diving site, the project divers also require reliable and efficient lighting systems.
© Ari Ritamäki 2000