industry and technology
The BAM-IS will replace the aging Neptune A-20, in service
for more than three decades
to 3,000 metres. Each one will have
two articulated arms with different
cutting devices. The advantage of these
vehicles is that, to keep a submarine
crew alive on the seabed at a depth
of between 300 and 600 metres, they
can both remotely connect ventilation
hoses to inject fresh air and extract
stale indoor air. The Neptune also has
two ROVs, but they have less capacity
to perform a wide range of tasks.
The ship will also be equipped with a
fully automated robotic vehicle similar
to the AUV (Autonomous Underwater
Vehicle). Shaped like a torpedo and
dedicated to performing tracking
activities at a minimum depth of 3,000
metres, its on-board computer will be
loaded with a software programme
to search for and locate the desired
objects. The two ROVs and the AUV
are complemented by an advanced
towed side-scan sonar, which will
transmit real-time images to the ship,
and by a system attached to the hull
based on two echo sounders: one single
and one multi-beam.
The ship’s second most important
mission will be to rescue crews of
distressed submarines that remain on
the seabed. In other words, to safely
rescue all those who are trapped and
isolated hundreds of metres below
the water’s surface. These are highly
complex and high-risk operations,
which usually involve the participation
of a large naval air task group,
often requiring close international
coordination.
The major leap forward is that
this new vessel will be certified as a
“mother ship” to house and use the two
main Western manned bathyscaphs
capable of conducting submarine
rescue operations. They are the US
Navy’s SRDRS and NATO’s NSRS
mini-submarines, designed for the
extraction and escape of trapped
persons as far as 610 metres down.
DYNAMIC POSITIONING
This certification means that the
vessel can be equipped with at least
one manned bathyscaphe and minisubmarines
designed to operate at great
depths and resist very high pressures.
These special mini-submarines are
adapted to “match the damaged
submarine, equalize pressures in both
vessels and progressively extract the
trapped crew”, explains Lieutenant
Commander Mínguez.
In fact, rescue operations remain
outside the Neptune’s scope of action,
although it is capable of supporting
them. This is due to the very limited
dimensions of its deck, which impedes
the accommodation of bulky rescue
means. It is also limited to a depth of
600 metres.
An important shortcoming of the
Neptune that will be incorporated into
the new ship, and which represents
a major technological improvement,
will be a dual redundant dynamic
positioning system, equipment which
must be integrated during the ship’s
construction phase as it is linked to
platform control.
This upgrade means that the BAMIS
will be able to remain automatically
stabilised at a fixed point. This is
achieved thanks to a sophisticated
software loaded into the main on-board
computer, hosting a mathematical
model, which integrates data from the
ship’s position sensors and combines
them with the effects of the wind,
waves, currents and gyrocompasses.
The computer obtains the
georeferenced position of the ship in
real time and instantly regulates the
operation of the propulsion plant and
propellers. The result is a force vector
that ensures the BAM-IS maintains
its position at all times. The main
advantage it provides is the capability
of conducting operations afloat either
when the seabed is too deep for human
intervention (90 metres), when there
are pipelines or underwater cables or
when anchoring is impossible.
The propulsion plant will feature
two axes that will develop the
necessary power to reach a minimum
sustained speed of 15 knots. Its
command and control equipment
will have satellite communications
fitted with cryptographic systems and
cybersecurity technology. It will have
a basic 48-strong crew, which can be
increased to a total of 80 in the most
Despite its age, the Neptune A-20 continues to accomplish the missions it was
designed for.
Armada
42 Revista Española de Defensa April 2021