If necessary, the batteries’ storage tanks could eventually be released to make the
submersible lighter in case of emergency. Archimède has one vertical propeller,
which allows it to more upward or down in the water column, plus two lateral
propellers and one at the stern, which enable the bathysphere to move horizontally.
Twelve light projectors providing a total of 1000 W are disposed around the
submersible.
The sphere has a diameter of 2.1 m and is composed of two hemispheres forged
in steel alloyed with nickel-chromium-molybdenum. When I dove inside the
Archmède, I had to enter the sphere by climbing down a ladder inside a narrow
access tube within the bathyscaphe’s hull. The sphere is able to host three persons
and is built to withstand 11,000 bars pressure, which is probably greater than the
pressure on the sea floor at any depth. The shell of Archimède’s sphere is 15 cm
thick and only the sphere itself weighs 19 tons. Once they have entered the sphere,
the three passengers, called divers, will breathe oxygen and release carbon oxide
and water vapor. Oxygen bottles and chalk (which can absorb water vapor) are
placed into containers in order to provide dry air. Archimède has the capability of
diving to all ocean depths. In order to see outside, the 2 crewmen and invited
scientific observer were obliged to look through individual binocular eyepieces.
The distortion of the image was such that things outside the bathyscaphe were
about 1.6 times larger than reality. This type of system was not very satisfactory
for an observer who needed to clearly identify various structural features or life
forms.
Archimède became operational in 1961. After a few tests in the Mediterranean
Sea near Toulon, in July 1962 Archimède made a historical dive in the Kuril
Trench (Japan) and reached a depth of 9,545 m. In 1963, Archimède was chartered
by the US Office of Naval Oceanographic Research and sent to San Juan (PortoRico) to dive into the Porto-Rico Trench. Nine dives were made between depths of
3,000 and 8,300 m in the Trench (Jarry 2003). The goal was to test the operational
aspect of the Archimède with some limited scientific prospecting. Sediment cores
and a few rock samples were collected. Other dives were made in the Mattapan
trench in Greece (1965), and again near Japan in the Kuril trench (1967). However,
the first comprehensive and coordinated scientific program with the submersible
Archimède occurred during the study of the North Atlantic spreading ridge system
in a project called FAMOUS (an acronym for French-American Mid-Ocean
Undersea Survey) which started in 1972 and terminated in 1974 (see Chap. 7)
(Riffaud and Le Pichon 1976).
Although bathyscaphes such as Trieste and Achimède have demonstrated their
capability for working at great depths and by making some scientific contributions,
their use is not really efficient. They are heavy, slow moving on the sea floor, and
also they are potentially dangerous since they use kerosene to maintain their
floatability. Furthermore, the extensive logistics of technical maintenance at sea
does not permit research missions to schedule dives on a daily basis. Also, the fact
that most instruments used on the sea floor are located underneath the bathyscaphe
60
3 Diving into the Abysses
submersible lighter in case of emergency. Archimède has one vertical propeller,
which allows it to more upward or down in the water column, plus two lateral
propellers and one at the stern, which enable the bathysphere to move horizontally.
Twelve light projectors providing a total of 1000 W are disposed around the
submersible.
The sphere has a diameter of 2.1 m and is composed of two hemispheres forged
in steel alloyed with nickel-chromium-molybdenum. When I dove inside the
Archmède, I had to enter the sphere by climbing down a ladder inside a narrow
access tube within the bathyscaphe’s hull. The sphere is able to host three persons
and is built to withstand 11,000 bars pressure, which is probably greater than the
pressure on the sea floor at any depth. The shell of Archimède’s sphere is 15 cm
thick and only the sphere itself weighs 19 tons. Once they have entered the sphere,
the three passengers, called divers, will breathe oxygen and release carbon oxide
and water vapor. Oxygen bottles and chalk (which can absorb water vapor) are
placed into containers in order to provide dry air. Archimède has the capability of
diving to all ocean depths. In order to see outside, the 2 crewmen and invited
scientific observer were obliged to look through individual binocular eyepieces.
The distortion of the image was such that things outside the bathyscaphe were
about 1.6 times larger than reality. This type of system was not very satisfactory
for an observer who needed to clearly identify various structural features or life
forms.
Archimède became operational in 1961. After a few tests in the Mediterranean
Sea near Toulon, in July 1962 Archimède made a historical dive in the Kuril
Trench (Japan) and reached a depth of 9,545 m. In 1963, Archimède was chartered
by the US Office of Naval Oceanographic Research and sent to San Juan (PortoRico) to dive into the Porto-Rico Trench. Nine dives were made between depths of
3,000 and 8,300 m in the Trench (Jarry 2003). The goal was to test the operational
aspect of the Archimède with some limited scientific prospecting. Sediment cores
and a few rock samples were collected. Other dives were made in the Mattapan
trench in Greece (1965), and again near Japan in the Kuril trench (1967). However,
the first comprehensive and coordinated scientific program with the submersible
Archimède occurred during the study of the North Atlantic spreading ridge system
in a project called FAMOUS (an acronym for French-American Mid-Ocean
Undersea Survey) which started in 1972 and terminated in 1974 (see Chap. 7)
(Riffaud and Le Pichon 1976).
Although bathyscaphes such as Trieste and Achimède have demonstrated their
capability for working at great depths and by making some scientific contributions,
their use is not really efficient. They are heavy, slow moving on the sea floor, and
also they are potentially dangerous since they use kerosene to maintain their
floatability. Furthermore, the extensive logistics of technical maintenance at sea
does not permit research missions to schedule dives on a daily basis. Also, the fact
that most instruments used on the sea floor are located underneath the bathyscaphe
60
3 Diving into the Abysses