VOL 71 No4 - Navy League of Australia

GROWTH IN STRENGTH: THE HOBART CLASS AWD . . . CONTINUED
The final ASW asset will be the ship’s multi role naval helicopter flight.
HOBART will probably go to sea with an existing RAN Sikorsky S-70B-2
Seahawk but will also be the first vessel to operate the AIR 9000 Phase
8 Future Naval Aviation Combat System. The centrepiece of this new
acquisition will be a Seahawk replacement helicopter reconfigurable for
ASW, anti-surface close and far and logistics support missions. The
Naval Aviation community is also interested in acquiring a unmanned
aerial system (UAS) to be controlled by the ship; though the single
hangar space on the Hobarts would preclude basing of anything but the
smallest UAS onboard in addition to the helicopter.
AIR WARFARE DESTROYER 2030
All of these systems, their crew and the means to move and sustain
them at sea, will be integrated within the AF-100 ship design. While
the F-100 draws much of its original design from the Arleigh Burke
class, combined with some European technology, it is a much smaller
ship, displacing only 5,800 tonnes compared to 9,200 tonnes of an
Arleigh Burke Flight IIA and 8,100 tonnes of the unsuccessful Evolved
AWD design. The F-100 had a considerable growth margin which has
been extended in the AF-100 to a maximum displacement of 7,000
tonnes. However, much of this has already been consumed with
additional systems over the F-100 baseline, leaving the AF-100 with a
displacement of 6,250 tonnes.
The remaining margin of weight will need to incorporate life time
improvements and a considerable capability upgrade announced under
the recent Joint Forces 2030 White Paper.
The Hobart class will receive two new weapons; the Raytheon RIM-
174A SM-6 extended range air defence missile, and a long range
strike capability, likely to be the 2,500 km (1,390 nm) range Raytheon
RGM-109E Tomahawk Land Attack Missile (TLAM) Block IV now with
loitering capability and in flight target reprogramming. Other likely
life time capability improvements could include a tactical Ballistic
Missile Defence (BMD) capability - though Joint Forces 2030 was noncommittal
on this matter - a naval UAS and radar array upgrades.
While the weight increase of all these systems will be incremental over
the current embarked weapons, fitting a useful magazine of SM-6 and
TLAMs onboard the Hobart class will result in displacing the existing
SM-2 and ESSM missiles. However, SM-6 will eventually provide a one
for one replacement for SM-2 with the USN keen to standardise to the
SM-6 and ESSM.
SM-6 replaces the legacy semi-active seeker of the SM-2 with the
active homing seeker array (in some cases not requiring terminal
illumination) from the AIM-120 AMRAAM air to air missile, enabling it
to be fired at targets beyond line of sight from the firing platform in fire
and forget mode. This enables it to engage targets over the horizon and
behind terrain if an appropriate CU like a picket ship or AEW&C aircraft
provides the targeting information. It can also be used in the semiactive
homing mode as the SM-2 using the same interception process
as detailed earlier.
A new longer ranged and more accurate ESSM is also being planned
to replace the current ESSM. The ESSM –ER (Extended Range) will
be fitted with a forward looking IR sensor to give it greater resistance
to electronic countermeasures, dual mode interception capability and
better explosive fuze settings for near miss engagements due to the
high closing rates of supersonic anti-ship missiles. Its range will also
be increased.
To provide an effective capability, at least 16-32 TLAMs will need to
be available to each Hobart class. USN destroyers frequently sail with
more than 45 TLAMs. Even displacing the ESSMs to another 16 VLS
cells added to the aft of the ship, like the short length version of the
Mk-41 SVLS or 32 dual pack Mk-48 lightweight VLS, would not provide
enough of a useful magazine for SM-6, ESSM and TLAM. This may
prove a weakness in the Hobarts service life and begs the question, is
three actually enough?
Soon to be a common sight, an F-100 (in this case ALVARO DE BAZAN) leaving Sydney Harbour. (Chris Sattler)
08 THE NAVY VOL. 71 NO. 4