Reason for
writing:
Should it
be Merlin, UAV or Osprey? As the E-2D is not an option with a STOL carrier
design as has been built for the Queen Elizabeth class, how Britain can innovate
its position into an advantage?
Key Words/Phrases:
·
VSTOL: Vertical/Short Take Off and Landing, the
cheapest system of carrier flight deck, but requires the most expensive
aircraft… the Royal Navy (RN) was the first navy to employ this to provide its
fixed wing airpower, but that was out of necessity when the first Queen Elizabeth class was cancelled
(CVA-01 was due to have been called after the Queen) and all it managed to get
built were the ‘Through-Deck Cruisers’ of the Invincible class.
·
CATOBAR: Catapult Assisted Take Off & Barrier
Assisted Recovery, the system used on most major aircraft carriers, it allows
for the widest range of possible aircraft to operate…but it is also more
expensive to install and maintain than the VSTOL flight deck, although that is
offset by its capabilities visa-vie aircraft operation.
·
STOL: Short Take Off and Landing
·
F-35 Lightning II (Joint Strike Fighter): produced in
multiple variants, B for VSTOL and C for CATOBAR, this is the new stealth jet
strike/fighter (what used to be called a Fighter Bomber…i.e. could fight its
way to the target, drop its bombs and fight its way back) coming into service
with the RN for the Fleet Air Arm to fly of the carriers.
·
Eurofighter Typhoon: Principle aircraft belonging to
the Royal Air Force at the moment, a Cold War inspired Dog-Fighter that was
used in conjunction with Tornadoes over Libya to do some limited bombing…
although it was the much more venerable Tornadoes which had to aim the weapons.
·
NATO: North Atlantic Treaty Organisation – Britain’s
principle strategic alliance,
·
AAD: Area Air Defence
·
UAV: Unmanned Aerial Vehicle
·
Surface Combatants: Corvettes, Frigates, Destroyers
and Cruisers…the back bone of any navy these are the vessels which provide the
presence/patrolling in peace, the task group fire power in war time and are
essential to pretty much everything a fleet can be required by its government
to do – sometimes is divided into Minor & Major surface combatants with the
size split at ~5000tons.
·
Aircraft Carrier: as defined by a paraphrasing of Admiral
Caspar John (1st Sea Lord) -
o
An air
field operating anything from thirty sixty to eighty aircraft; with the fuel,
stores, fire-fighting equipment and so on which go with it.
o
A couple
of batteries of heavy anti-aircraft defences with ammunition and control gear.
o
A minor
Battersea Power Station.
o
A big
radio transmitting and receiving station.
o
The radar,
communications and other ancillaries equivalent to an RAF fighter sector
controller.
o
Consider
all the personnel (about two thousand) and accommodation wanted for these
functions, then issue them all with three month’s provisions
o
Now put
the whole lot inside a metal box eight hundred feet long by ninety feet wide, by
about ninety feet high, make the box self-propelled and operate aircraft from
the top of the lid.
o
There is
your Aircraft Carrier.”[1]
·
LPH: Landing Platform Helicopter – like an aircraft
carrier in terms of having a large flight deck/island configuration, but
doesn’t carry fighter aircraft and concentrates on troop transport.
·
LHA: Landing Platform Helicopter/Attack – basically an
LPH but with the ability to operate fighter aircraft of the VSTOL type.
·
LHD: aviation wise similar to an LHA usually, but as
well as flight deck it also has a stern ‘dock’ that landing craft can operate
out of allowing troops & heavy equipment to be sent ashore
·
Aviation ship: generic term used to cover any vessel
where the primary method of functioning within it’s role is the support of
aviation, i.e. aircraft carrier, LHA or LHD.
·
Radar Horizon = the distance at which an
aircraft/ship can be detected on or traveling as close as makes no difference
to the surface of the earth = √(2xHx(4Re/3))
o
The radius
of the Earth used is 20,925,524.9ft, and is represented by Re.
o
Height of
the radar above the surface is represented by H.
o
While
every attempt is made to make the figures given as accurate as possible they
are only general guides as there are some factors such as the transmitting radar's
power, pulse length and Pulse Repetition Frequency, PRF, and the target echoing
area are either protected information or unknown.
Context:
Airborne Early Warning is not a
luxury, it’s not even a benefit, it’s a necessity in modern warfare. With it
task forces can see around the curvature of the earth; a crucial capability
when facing sea skimming hypersonic missiles or just low flying aircraft the earlier the
detection the less the chance that anything unfortunate will happen.
It was a lesson re-learnt at a cost
in the Falkland’s war, where there was no such capability; it having been lost
with the retiring of HMS Ark Royal
and her Gannets in 1978. It took two years after the war was over and lot of
treasure for the current aircraft, (which are still in service currently) the
Sea King Mk 7 AEWs, to be brought into service. However, the Sea King was not a new aircraft
in 1984 (in fact the Falkland’s War was where the ASW and Commando or ‘Junglie’
versions had proved their metal), so now in 2013 it is unsurprising that it is
time for them to be replaced.
With this in mind a de facto replacement
has emerged in terms of an updated version based upon the new medium helicopter
stalwart off the RN, the Merlin. This presumptive direction of development
however is not the only option and due the importance of this role to the fleet
especially, but also to Britain’s armed forces capabilities as whole, it is
worthwhile considering what other options there are.
Broadly speaking, and discounting
E-2D Hawkeye due to the fact that the Queen Elizabeth’s are STOL aircraft
carriers not CATOBAR,
there are four options that conceivably offer a solution to the need for AEW
RN:
·
Option 1: Merlin
·
Option 2: Osprey or AW609
·
Option 3: UAV
·
Option 4: Merlin & UAV
The trouble for all these options
is they also have to advance on what is already acknowledged as an excellent
capability, the Searchwater 2000 Radar having evolved to not only be able to
watch the sea and the air, but also the land – proving itself a major asset in
the war in Afghanistan, as well as Libya and countless other operations.
|
|
|
Figure 2.
Searchwater 2000 AEW Radar
|
Before getting into the analysis of
the options, the aircraft’s ceiling or operating is going to be referred to a
lot, because it’s important. The table below explains why; the high an AEW
aircraft can operate at the better. For example the horizon difference between
30 & 20,000ft is nearly 40 Nautical miles; or 2.5x the Radar Horizon of the
S1850M Radar that will be mounted 184ft up on the Queen Elizabeth Class Aircraft Carriers (now Radar Horizon is not
the maximum range of detection, it’s at what point the curvature of the earth
begins to interfere) – the highest mounted radar system in the fleet without an
in service AEW system.
|
Height
above sea level Ft
|
Radar
Horizon in Ft
|
Radar
Horizon in nautical miles
|
Difference in detection
range to 20,000ft
|
|
20000
|
1056422
|
173.8646
|
0
|
|
21000
|
1082511
|
178.1582
|
4.2936
|
|
22000
|
1107985
|
182.3507
|
8.486132
|
|
23000
|
1132887
|
186.449
|
12.58441
|
|
24000
|
1157253
|
190.4591
|
16.59453
|
|
25000
|
1181116
|
194.3865
|
20.52193
|
|
26000
|
1204507
|
198.2362
|
24.37155
|
|
27000
|
1227452
|
202.0124
|
28.14781
|
|
28000
|
1249976
|
205.7194
|
31.85477
|
|
29000
|
1272101
|
209.3607
|
35.49611
|
|
30000
|
1293848
|
212.9398
|
39.07518
|
|
31000
|
1315235
|
216.4597
|
42.59508
|
|
32000
|
1336280
|
219.9233
|
46.05866
|
|
33000
|
1356999
|
223.3331
|
49.46853
|
|
34000
|
1377406
|
226.6917
|
52.82711
|
|
35000
|
1397515
|
230.0013
|
56.13665
|
Key Points:
Option 1: Merlin
The primary option; what is being
actively pursued, 14 airframes have apparently already been allocated to be
upgraded from the original ASW variant to and AEW version. The trouble is that
there are two variants on offer. Thales are putting forward the solution of
just transferring the Searchwater System from the Sea Kings to the Merlin’s – a
solution which offers rapid turnaround perhaps ending the reality of an AEW
capability gap.
However, Lockheed Martin are putting forward a system based around the radar
that’s being used in the F-35 offering (at least theoretically) potential
savings in logistics & training thanks to commonality and advantages in
terms of capability. Unfortunately the Lockheed Martin is the missing dinner
today to have a feast for lunch tomorrow option.
Furthermore, whilst any system might
produce the better aircraft/better radar than presently in service, they are
still limited in altitude terms by the lack of a suitable cabin space.
Therefore making any improvement offered in reality less valuable as they will
still be limited by the curvature of the earth.
|
|
Figure 3. Merlin Helicopter Plans
|
|
Figure
4. An Early Thales Proposal
|
|
|
|
Figure
5. The more recent Thales Proposal
|
|
Figure
6. The Lockheed proposal envisages pods on both sides of the aircraft
|
|
Option 2: Osprey or AW609
The alternative to a helicopter of
course is a tilt rotor, and despite some popular assertions there is more than
one option for that breed of aircraft. The primary option though is the MV-22
Osprey, an aircraft which has proved itself to an extent in combat but which also
has suffered for the trials, tribulations and expenses of being the first tilt
rotor aircraft to enter service. This has pushed up not only development costs
but also implementation costs, because whatever theoretical points of
similarity there are between helicopter’s and tilt rotors proved of less help. However,
for AEW work the V-22 0sprey does
have advantages, a 20,000lb internal carry capacity with an alternatively
15,000lb external carry capacity would mean it’s base design has the potential
to be very useful as an AEW aircraft; it’s capacity and flight profile mean it
could also make a very useful tanker aircraft. However,
at the moment it lacks a pressurised rear cabin – meaning before any conversion
to AEW configuration (i.e. adding radars and the various control terminals
inside the aircraft) to offer a meaningful advantage over a helicopter it would
have to be pressurised. Whilst speed and range are great assets; an AEW
aircraft isn’t a fighter - it doesn’t have to be fast, it does have to be stable…
and the range that matters most is the detection range it’s radar provides,
something for which ceiling matters more than anything else.
|
|
|
Figure 7. A V-22 Osprey at work
|
The Augusta Westland 609 is
smaller, has less lift capacity and is in fact beaten by the Osprey in many
ways, but it does have a pressurised cabin. Although it’s current ceiling is
registered as the same as the Osprey it could conceivably operate at a higher
altitude. However, for the UK this would be an even more expensive project than
the V-22 Osprey as it would be the
sole military user, and the requirements of military aviation in terms of
protection & system redundancy are far more exhaustive – as is required by
the fact that military aviation will likely as not come under fire with the
intent of blowing it up, whereas civil aviation hopefully will not.
|
|
|
Figure 8. An AW 609 in flight
|
Tilt rotor aircraft are going to be
a major feature in future wars, the V-22
Osprey already has been; they are certainly the vogue and in the future
when the technology has matured they will offer dramatic advantages that will
be definitely worth investment. However, at the moment as good they are, they
are also expensive, they would add a further logistics train to the RN for a
comparatively niche/role number (if they were being used to provide the
replacements for the Junglies and an order of 60 or so airframes was made then it
might be worth considering but as that is not the case…), and of course there
is the fact that adding the aerodynamic intricacies of an enhanced external
radar system to an aircraft that already fights with the laws of physics might
well have very interesting results. This means that for the time being it seems
sensible to put the option to one side… but it’s not the only option.
Option 3: UAV
A lot of trouble is being taken
& money is being spent to build manned AEW aircraft (most importantly these
are going to use up to 14 Airframes which could be used for troop transport or
ASW or…), yet they replicate effort – the space in the back of a helicopter or
plane is a confined replica of the command & control capabilities that already
present (and has to be present) inside an Aircraft Carrier or an AAD.
Furthermore flying an AEW helicopter is boring, requiring a high degree of
attention for many hours doing a repetitive job.
Such a course of action therefore
seems very strange in the light of recent developments with unmanned aircraft –
especially that UAVs seemingly have not even been considered. An illogical
finding considering that unmanned aircraft can fly higher than a manned because
it’s lack of a pressurised cabin has no bearing; at a high enough altitude it
might also work as a communications relay. It can hold position for hours
without getting tired or bored, and most importantly in a world where
needlessly endangering service personnel lives is increasingly frowned upon it
would reduce exposure of personnel in something which by its very nature is
very visible to the enemy.
There are two option sets the
British Government could pursue either Rotary UAVs or Blimp UAVs; both of which
would have advantages & disadvantages. Certainly from the perspective of
the larger space offered by an aircraft carrier a Blimp UAV
which could fly higher, and stay on station longer would be very attractive.
However, the general purpose utility of a Rotary UAV -
that it could be used to carry equipment, mount weapons or act as a scout –
from the perspective of surface combatants this would be exceedingly useful, a
force multiplier that would build on the ScanEagle that’s recently been brought
into service.
Whereas in comparison to the increased
manpower and increase cost of manned units (both in terms of £ and space – a
finite commodity aboard ship); multiple UAVs could be used, with perhaps only
one or two transmitting whilst others are just acting as receivers. This would
have several advantages, for example if one of the transmitting units has to
drop out of position for some reason, it can be replaced by just flicking a
switch. More importantly stealth mainly works not by making the radar signals
disappear, but by deflecting them away from the receiver; therefore the more
receivers tuned within a radar network, the greater the chance of detecting an
enemy stealth unit (whether it travels by air, land or sea).
Further to all this, there is not
exactly a dearth of existing off the shelf options -maybe in terms of blip, in
which case a search of the internet suggests a lot of work is being done on it
but as yet no real working prototypes. In terms of Rotary UAV capable of
carrying a equivalently powerful sensor suite to that proposes the Boeing A160
Hummingbird (has had some good results and has already worked with the Forester
Radar system,
but has also crashed), the Boeing Eagle Eye (was ordered then cancelled by the
United States Coast Guard) and possibly the best on paper for ease of implementation
the Northrop Grumman MQ-8 Fire scout that is already in service with the USN –
with 27 of the 168 planned already operational. The
table over page allows for a quick comparison between these options and the two
primary manned options.
|
Maker
|
Designation
|
Type
|
Endurance
|
Speed
|
Load
|
Ceiling
|
|
Augusta Westland
|
AW101 Merlin
|
Helicopter
|
5hrs
|
167knots
|
9,000lbs
|
15,000ft
|
|
Boeing
|
V-22 Osprey
|
Tilt Rotor
|
-
|
300knots (at 15,000ft)
|
20,000lb of internal or
15,000lb of external
|
25,000ft
|
|
|
Helicopter
|
20+hrs (at 15,000ft – longest
flight so far 18.7hrs)
|
165knots
|
2,500lbs
|
20,000ft (limited by engine
certification); capable of 30,000ft
|
|
Eagle Eye
|
Tilt Rotor
|
6hrs
|
195knots
|
200lb
|
20,000ft
|
|
Northrop
Grumman
|
|
Helicopter
|
5hrs (with 600lb load)
|
115knots
|
600lb
|
20,000ft
|
|
|
Helicopter
|
14hrs (with 600lb load)
|
115knots
|
600lb
|
20,000ft+
|
|
E2D
Hawkeye
|
Fixed
Wing
|
6hr
|
350knots
|
-
|
34,700ft
|
Unmanned
= Bold
There are of course many other UAVs
but the criteria were that they should be available, and able to carry the
radar, a mixture of other sensors and the requisite communications equipment. After
that anything else would be a bonus.
Figure
9. MQ-8B Fire Scouts conducting operations aboard the USS Halyburton
(FFG 40) during its second at-sea deployment
|
|
|
|
|
Of these it’s the MQ-8C which would
offer the best package available, procuring 24 to support the surface
combatants (as currently planned Type 26s & Type 45s)
and a further 24 for Aircraft Carriers and ships of the Amphibious Task Group,
would cost 48x $18.2million (fly away cost)= £562million – before the additions
of radars, training and integration costs.
For that the RN would gain 48 AEW aircraft, or 48 long range scouts, 48
communication hubs, 48 gunships, and because the MQ-8C has been designed to
assist with logistics 48 cargo-carriers. The fact is the number put forward would be
primarily for AEW but would also be more than capable when it came to other
missions. They would provide every surface combatant commander with the option
of putting up their own dedicated ‘all seeing’ ‘eye in the sky’ should they
need to. The radar and the sensors would
be attachment, rather like the weapons containers in the stanflex system
could be taken in and out of service for maintenance without affecting the
aircraft; they could be updated or modified just as quickly with no disruption
to service. Under current circumstance this would be an advantage as it would
make the choice of radar very simple – the current Searchwater system could be
used until a better one comes available, retaining the value of the money
invested in the Lockheed Martin system…but crucially allowing more time for it
to be implemented.
|
|
Figure 10. A Boeing A160 Hummingbird carrying a Forester Radar system
|
Option 4: Merlin & UAV
There are though some who will feel
that taking back command and control to the carrier is a regression; well of
course there is a middle way. A way which would still save precious Merlin
airframes and protect lives on operations; this would again involve the sensor
suite being carried aboard UAVs, but when a task group is instead of the data
just being fed back to the carrier it would also be transmitted to a Merlin
equipped to act as a Forward Airborne
Control Aircraft (FACA); something which could be very useful when
providing protection for a deployed land force or when it’s necessary to push
the air defence network beyond Line of Sight communication range.
Such a scenario would actually make
it far easier on the merlin airframes, as has been covered, the type and
position of the sensor suite has offered many problems with the design
therefore by taking that out, and instead increasing communication facilities
and having more terminals to allow for both control of UAVs as well as to
maintain situational awareness/direct the battle.
Advantages of this arrangement
would be that escorts could benefit from UAVs, and the aviation ships would
have a UAV/Merlin mix giving them a greater level of flexibility… instead of
13-14 aircraft being necessary, 6-7 could be used to provide these Forward Airborne Control Aircraft – only
2-3 would be required per aircraft carrier as they would not need to be
operated continuously, but as required by operations.
A continuation of all this produces
the option that the control systems could be palletised, along with the
commando seats and the ASW systems; so that instead of the helicopters being
assigned fixed roles, they would be able to be easily adapted to roles as
required. Helicopters aboard aviation ships would under this circumstance no
longer be pre-defined assets but would be adaptable units increasing the
flexibility of the air group be orientated to provide the best capability for
any operation. Therefore no longer would 16 helicopters be, 6 ASW, 4 AEW and 4
Commando, but instead would be 16 airframes. Airframes which in times of transit
when the threat would be aircraft, submarines or ships could be 2 FACA and 14
ASW; yet in support of an amphibious operation these could be transitioned to 5
ASW, 3 FACA and 8 Commando – supplemented at all times by UAVs, UAVs which if
the MQ-8C Fire X was procured would be able to act as sensor suite, gunship,
scout and cargo-carrier.
Points of Interest/Brief History of AEW in RN:
·
AEW in the Royal Navy started life as binoculars
and flairs in the hands of Observers flying in the backs of Spotter aircraft in
the 1920s. This system was a tactical operational development by the RN and its
Fleet Air Arm (FAA) in response to the limited detection range then possessed
in the face of the growing speed (primarily, but also other capabilities) of
aircraft; as well as the evolving capabilities of ships and their guns. In the
pre-radar world this was the state of the art response; and it worked. During
many exercises in the 1920s it proved its worth; it was not full-proof but it
was a large improvement over the situation prior to its introduction. Whilst
this was not the end of the British story; lack of funds and the focus of
British technical development on primarily other applications means the next
phase of its development was led by the United States Navy (USN).
·
The USN in World War II (thanks to new
technologies, and evolutions in strategic thinking) faced a range of problems
much the same as the RN did, baring one thing. The USN had an advantage over
their transatlantic counterparts - whereas the RN had to face the world in
order to protect an Empire and a Commonwealth which spanned it, the USN had to
face just one ocean and just one navy, the Imperial Japanese Navy (IJN). This
allowed for a specialisation of sorts to take place in their air arm; a wider variety
of the types of aircraft to be carried in comparison to the consolidated RN air
groups which were a primary feature of their response to their global
commitments. Even with this and less completion for radar scientists, the USN
actually ordered their first system, Cadillac, just eight months prior to the
first Kamikaze attacks.
It was ordered with the intention of supporting operations as part of War Plan
Orange. It was very basic, a Grumman Avenger fitted with AN/APS-20 radar. It could detect small ships and aircraft
formations at ranges of up to 100 miles; a substantial increase over the 30
miles a ship mounted radar was then capable of achieving. It allowed fighters to be directed on to
Japanese formations before they got within their strike range; increasing the
chances of that attack never getting through.
It was a cornerstone of the Big Blue Blanket alongside the picket
destroyers.
·
The RN was very covetous of this system, but
unfortunately the war ended and the purse strings were tightened before they
could acquire their own version. However, the post-war government of Clement
Atlee declaring another 10 year rule to be in place; it was very unfortunate
for them when just five years later the Korean War broke out in June 1950. So
in 1951 the second ten year rule was discarded; the RN immediately purchased
fifty Skyraider AEW aircraft from the US, and formed up 849 Squadron with the
role of providing training, integration and every carrier with a flight of four
aircraft. They proved their worth… so much so that the RN did not have to fight
hard in the halls of Whitehall to justify their replacements.
|
|
Figure 11.
A Flight of 4 Douglas Skyraider AEW of the RN
|
|
Figure 12.
A Fairey Gannet AEW 3 flying over HMS
Eagle.
|
|
·
Their replacements were Fairey Gannets, the
first home grown AEW – although it did make use of the AN/APS-20 radars which
had been fitted to the Skyraiders. It
was an aircraft and a system which once inspired an American pilot seeing it
flying, to declare he had found God.
The Gannet was ungainly, but it did the job; whilst the RN had carriers capable
of operating conventional fixed wing aircraft it gave them what they needed –
warning, the ability to monitor the space around the fleet for hundreds of
miles in any direction providing the RN with great operational security and
flexibility. But, unfortunately, the 1967 carrier decision brought this to an
end, with the big carriers and their air groups of AEW, Strike Aircraft, Fighters
and ASW helicopters being retired from service as a cost saving measure. This
was not though the end of AEW for Britain.
·
The Falklands war was a wake-up call, every
single ship lost, as well as the on-going supply of the Argentinian forces by
C-130s can be put squarely at the feet of lack of AEW. Without it the carriers
had to operate further away from the islands, without it the Sea Harriers on
Combat Air Patrol (CAP) could not operate far enough up-threat and were
therefore always playing catch up to Argentinian raids, and without it ships on
picket duty were exposed bastions – rather than providing a mutually supporting
defensive line as the Big Blue Blanket of World War II had achieved. This is
not to say that no ships would have been lost had there been AEW aircraft
present; but it is very reasonable to assume far fewer ships and many less
personnel would have been lost. Under these circumstances the current RN AEW
system was born.
|
|
|
Figure 13. A Sea King Mk 7, the current fleet AEW, that has served with
distinction & purpose in countless conflicts since it's entry into
service, but most recently Afghanistan and the Gulf
|
Summary:
In the current circumstance of
defence it’s Option 1 which is the most likely to come about, probably the
Lockheed Martin version as the actual spending of money could be put off
longest. It’s not really sensible or practical in terms of force security but
under the current economic climate it’s the Treasury which will most likely
have the final say and they are watching the pennies very careful as the
British economy is drawn back from abyss that Greece, Spain and other countries
have fallen into. Which is a great shame because really its options 3 or 4
which should be chosen, option 3 would be very bold & brave and therefore
is not a likely course of action.
However, option 4 where the UAVs
could be employed from frigates, destroyers, auxiliaries – anything, just as
long as they had the right pods aboard; therefore giving every vessel it’s own
AEW protection, without taking up the space of an extra helicopter. The
capabilities this would bring to counter piracy, counter drugs, the
constabulary duties of a navy in ‘peace’ time would be amazing… it would be a
massive force multiplication, still not allowing a ship to be in two places at
once but would certainly multiply that ship’s area of effect. The Aircraft
Carriers would be the ones to make use of the FACA as has already been
espoused, able to provide forward of aircraft over a beach head or on-going
land operation whilst the fleet operates many miles out to sea away from the
problems of inshore waters.
The biggest difference Options 3
& 4 would bring though would be sheer numbers, if the situation arose that
it was necessary then a Task Group could be surrounded by a ring of
synchronised airborne radar, providing an almost physical barrier to any
attack…or more likely mount multiple AEW surveillance flights over not just the
Task Group but other strategic points within its area of operations. Allowing
the Task Group to provide security & over watch for minimum effort, but
achieving maximum impact.
Further Reading:
