Diehl Defense from Germany is back at the Singapore Airshow
promoting a number of defense systems which are of high value to
customers in Asia. Particularly interesting is the IDAS (Interactive
Defence and Attack System for Submarines). This unique submarine
launched anti-helicopter weapon is designed to protect attack submarines
from anti-submarine helicopters, as they become vulnerable hovering low
above water, dipping their sonar in search of enemy submarines. This
subsonic missile is optimized to seek out such slow targets, which pose
significant risk to a submarine operating at littoral, ‘brown’ waters.
Four
missiles will be stored in a magazine that fits into a standard 21″
torpedo tube. The missiles are ejected from the magazine into the water,
extract their wings and separate quietly from the submarine, where they
ignite the rocket and transition to airborne flight, propelled by the
weapon’s rocket motor.
One of the development
challenges was the propulsion system. The same rocket was required to
provide thrust for both underwater and airborne flight. The rocket was
designed to sustain the missile’s at optimal velocity in submerged
flight, and accelerate to subsonic flight while airborne, reaching
effective range of 20 km. Another concern was sustaining the
optical-fiber through the transit below and above water. Diehl’s
engineers were concerned how the fiberoptic bobbins will behave in the
different environments (below and above water) the test provided clear
evidence this will not be an issue.
Diehl initially
considered using the IRST seeker for IDAS, however, this high
performance and all aspect seeker may not be the only option, and other
seekers might be considered to pick up the target, provided with
passive cuing from by the submarine sonar. The submarine can acquire ASW
helicopter when submerged, by localizing the ripple effect created by
the rotor downwash. According to Diehl, the accuracy of such cuing
system is adequate to provide bearing and range, bringing the missile
seeker to autonomously acquire the target with high level of confidence.
The fiber optical link would then be used by the crew to verify the
target, confirm the intercept and perform battle damage assessment.
IDAS
was originally developed for the German Type 212 submarines but the
program has since frozen due to German defense budget cuts. Originally
the missile was planned to become operational in 2014 but this timetable
is now unlikely as the German Navy acquisition programs have stalled
recently due to lack of funding. Diehl is currently talking to
international partners seeking bridging funding for the program, to
sustain the development through the next stage.In few years, Diehl is
confident the high interest in the program will turn into formal
endorsement by foreign navies that have already expressed much interest
in the program.
For the missile development Diehl
has teamed with Submarine builder HDW, which is now part of the
Thyssen-Krupp Marine Systems (TKMS). Originally the weapon was designed
to be integrated in the HDW Type 212 submarine but, according to Diehl,
it can be integrated with other HDW types.
IDAS
is formally still in the proof of concept phase, which culminated four
years ago in a submarine launch performed by the German Navy U33 Type
212 submarine in 2008. This test examined the underwater launch system,
with the missile ejected from the torpedo tube, igniting the rocket
under water, separating from the submarine without leaving significant
signature (avoiding exposure of the submarine location). Following this
maneuver IDAS performed a course change under the water, streaking
vertically into the air. Back in 2008 the test focused on this
transition phase, with future tests, to be performed when funding is
available, would continue with full flight, target acquisition, guidance
and battle damage assessment.
