Sunday, December 21, 2008

Weekend Wings #30: Carrier aviation in the US Navy, today and tomorrow


Carrier-based aviation in the US Navy finds itself in a difficult position today concerning its overall strategy, and even its very reason for being. This Weekend Wings will examine some of the issues involved, and look at how the USN is addressing them. However, before doing so, we must examine the environment within which their aircraft carriers will operate. (Click this and all photographs for a larger view.)



USS Nimitz


Critics of the USN's huge carriers allege that they're easy targets for today's missiles and guided weapons, and unlikely to survive for very long in a major war. This may possibly be true. Certainly, no-one's yet experienced the effect that multiple hits from major missiles like the Russo-Indian BrahMos, shown below, would have on a Nimitz class carrier: but it's likely they'd be pretty devastating. I doubt whether the ship would be able to continue operations, even if it wasn't sunk.






BrahMos can be launched from land-, sea- or air-based platforms, and strike targets up to 180 miles distant. The current version of this missile cruises at up to three times the speed of sound, and a hypersonic version is under development, planned to have a velocity of over Mach 5. Other anti-ship missiles, such as the USN's own Harpoon, the Russian 3M-54 Klub, the European Exocet, the Swedish RBS-15, the Israeli Gabriel, the Chinese C-802 and C-803, and the Taiwanese Hsiung Feng II and III, are slower than the BrahMos, but some have greater range and/or a larger warhead.

Even a single hit from such a missile can devastate a modern warship, as the following examples show. The Royal Navy destroyer HMS Sheffield, shown below, was struck by a single Exocet missile, launched from an Argentine aircraft, during the Falklands War in 1982. The resulting fire crippled her, and she eventually sank after rough seas flooded her through the holes made by the missile.




The Oliver Hazard Perry class frigate USS Stark, shown below, was hit by two Exocet missiles, fired from an Iraqi warplane, in 1987. Only one exploded, but the damage crippled the ship, rendering her combat-ineffective, and took over a year to repair.






The Israeli Sa'ar 5 class corvette INS Hanit, shown below, was struck by a Chinese C-802 missile, fired by the terrorist movement Hezbollah, off the Lebanese coast in 2006. The impact and explosion fractured the hull from keel to superstructure, and the resulting fire destroyed much of the ship's electrical network. She was forced to curtail operations and return to port for repairs.






All told, fourteen vessels have been damaged or sunk in attacks by anti-ship guided weapons since 1966. Carrier critics point out that the USN's current air defenses (aircraft-launched missiles such as the AIM-120 AMRAAM, ship-launched long-range missiles such as the RIM-67/156 Standard, plus short-range point defense systems such as the RIM-116 Rolling Airframe Missile, 5" cannon and Phalanx Close-In Weapons System) would have great difficulty dealing with a mass missile attack by most current-generation weapons, and probably couldn't cope at all with BrahMos and future hypersonic missiles. They claim that the only way for the USN's carriers to survive such threats would be to remain outside their launch envelope - which would also put the carriers so far away from their own targets that they'd probably be rendered ineffective.

Certainly, the proliferation of anti-ship missiles is cause for serious concern to any Navy. India and Russia are on record as planning to produce up to 2,000 of the BrahMos series, of which up to 1,000 are intended for export to other nations. Already over 50 nations operate anti-ship missiles of greater or lesser capability, and that number is likely to increase in coming years.

The equation is one of simple cost-effectiveness. A USN nuclear-powered aircraft-carrier, including its wing of aircraft and all supplies and munitions, has a replacement cost of the order of $15-$20 billion. Add to this her usual escort of a cruiser, a destroyer and a frigate, plus a supply ship or two, and the replacement cost of a carrier battle group exceeds $30 billion.




An anti-ship missile such as the Chinese C-802 can be purchased for less than a million dollars. If an enemy launched a mass strike against a carrier battle group, using, say, 200-300 such missiles, there's no way in the world the latter would be able to shoot them all down before they reached their targets. For a start, the vertical launch long-range missile systems in the cruiser and destroyer only hold 96 missiles, not all of which are for anti-aircraft or anti-missile use. Even if every weapon was accurately targeted, they'd run out of ammunition before destroying even half the incoming missiles. The surviving missiles would unquestionably at least disable, if not sink, all the ships in the battle group. Thus, for an investment of about a quarter of a billion dollars, an enemy can neutralize a hundred times that value in US weaponry and equipment - not to mention causing massive casualties amongst US personnel. Not a bad deal, from an enemy's point of view.

However, all is not as bleak as it may appear on the surface. The USN has been facing a missile threat since the 1960's, and its structure, equipment, weapons and tactics have been developed to confront and defeat that threat. Just as missiles have improved over the years, so have defenses: and today's hypersonic missiles are engendering new responses that may change the nature of sea warfare as we know it.

The USN's primary response to the missile threat is to keep their launching platforms out of range of its ships. This is sometimes achieved simply by stationing the carrier battle group at a safe distance from any threat. However, geographical and operational constraints don't always allow this, so a layered system of defenses has been set up to deal with incoming fire.

The first layer is distant attack of launching platforms. Airborne early warning aircraft such as the Grumman E-2C Hawkeye series can track enemy ships and aircraft out to 300 miles or more, within a three-million-cubic-mile surveillance envelope, and pass targeting information to other aircraft and ships.




The new E-2D Advanced Hawkeye, currently under development with two prototypes already flying, promises a quantum leap in performance. The Hawkeye can direct other carrier aircraft to intercept and destroy enemy ships and planes before they get close enough to launch missiles. If enemy missiles are launched, the Hawkeye can track them and direct aircraft to intercept them at longer ranges. It will also pass its information to the ships themselves via datalink. The AEGIS combat system aboard US cruisers and destroyers, with its distinctively-shaped hexagonal phased-array radar panels, is designed to track and engage scores of targets simultaneously, directing long- and short-range defensive missiles and guns.






US warships also have comprehensive electronic warfare and decoy systems, details of which are highly classified. The USN maintains that this layered system of defenses is likely to defeat most potential attack scenarios.

Personally, I doubt that any gun- or missile-based defense system can beat off an attack by massed anti-ship missiles in large numbers. The reaction time available to the defenses is just too slow, and the time of flight of defensive weapons too long, to be able to succeed against a sufficient number of incoming targets. However, directed-energy weapons such as laser beams are on the horizon. The first such system to be commercially available, Northrop Grumman's Firestrike, is already being marketed. More will follow. Today's lasers are powerful enough to blind the sensors of an incoming weapon, and within ten years their power output is expected to reach a level that can destroy an aircraft or missile.

This will change the air-defense situation completely. It may even render manned aircraft too dangerous to fly over a battlefield, or against a naval combat group. You see, light-speed weapons don't need to make any allowance for the motion of their target. Their beams are so fast that they reach the target virtually instantaneously. This means that if the weapon is correctly aimed, its target is as good as dead. It won't be possible to evade them. If each warship carries enough of these beam weapons, and its combat systems can re-target them quickly against multiple threats, even a 'swarm' attack by anti-ship missiles may no longer be enough to defeat a carrier strike group.

(It bears mentioning that the power requirements of such weapons will be astronomical compared to current missiles and guns. This is where the nuclear-powered warships of the USN, with their vast electrical generation capabilities, will have a distinct advantage.)

Of course, submarine attacks won't be detected or deflected by such countermeasures. Anti-submarine warfare (ASW) used to be a top priority of the USN, but with the demise of the Soviet Union, it took second place to the global projection of maritime power. Now that many nations are acquiring modern submarines, capable of launching anti-ship missiles as well as torpedoes, the USN is placing renewed emphasis on the ASW mission, which will hopefully lead to improvements in defenses in that area as well.

Let's accept, therefore, that while a carrier battle group may be vulnerable to a massed missile attack, this is offset to at least some extent by appropriate tactics and its existing defenses, and will be further reduced by a new generation of defensive weapons. The carrier will probably remain a viable platform for the naval air arm, albeit with the risk of some losses in time of war.

At present, the USN operates ten nuclear-powered aircraft-carriers: one of the Enterprise class;



USS Enterprise


and nine of the Nimitz class.



USS Abraham Lincoln


A tenth Nimitz class carrier is to be commissioned in 2009. The first of a new generation of aircraft carriers, the Ford class, is under construction, and is expected to enter service in 2015.



Artist's impression of USS Gerald R. Ford


The latter two classes each displace approximately 100,000 tons at full load, and are very comprehensively equipped to sustain operations globally.

Although not, strictly speaking, regarded as 'aircraft carriers', the USN operates several amphibious assault ships that carry US Marine air components (often with some USN aircraft attached). At present there are two Tarawa class and eight Wasp class vessels in commission, with the first of the new America class vessels scheduled to be delivered in 2013, replacing the Tarawa class.



Wasp class amphibious assault ship


Each of these ships displaces more than a World War II Essex class aircraft carrier. However, they lack the catapults and arrester gear needed to operate modern carrier planes. Instead, they carry several dozen vertical/short takeoff and landing (V/STOL) aircraft. Types and numbers can vary by mission, but usually include US Marine Corps AV-8B Harrier II strike aircraft, plus a mixture of CH-46 Sea Knight, CH-53E Super Stallion, UH-1N Huey, AH-1W Supercobra and SH-60F/HH-60H Seahawk helicopters. Over the next few years the new F-35B Lightning II will replace the AV-8B's, and older helicopters will be first supplemented, then replaced, by MV-22B Osprey aircraft and UH-1Y Venom, AH-1Z Viper, CH-53K Super Stallion, and possibly later-model SH-60 Seahawk helicopters.

Having looked at the ships, what about the carrier air arm itself? What problems confront it today, how are they being overcome, and what does the future hold?

The aircraft aboard an aircraft carrier are organized as a Carrier Air wing. This used to be known as a Carrier Air Group, and the Commanding Officer of a Carrier Air Wing (a Navy Captain or USMC Colonel) still uses the acronym CAG from this legacy (perhaps because CAW would be too undignified!).

A Wing is made up of squadrons, as well as detachments from some squadrons, totalling 70-80 aircraft in peacetime. As a representative example, let's look at the US Navy's Carrier Air Wing One as it's made up at present, comprising eight squadrons and/or detachments:



The four Hornet/Super Hornet squadrons, each with 10-12 aircraft, perform fighter and strike missions; VAW-123 provides airborne early warning; VAQ-137 fulfils the tactical electronic warfare function; HS-11's mission is anti-submarine warfare and support of fleet and air operations (e.g. air/sea rescue, vertical replenishment, etc.); and VRC-40 transports supplies and personnel between the carrier and shore bases.

There are ten Carrier Air Wings in the US Navy. Each is usually assigned to a particular aircraft carrier for a period of some years, but may be reassigned to another (for example, when the first goes out of commission for extended maintenance). It's sobering to think that a single Carrier Air Wing comprises more striking power than the entire Air Forces of many smaller nations!

One deficiency that will be immediately apparent to sailors of the second half of the 20th Century is that the air wing lacks the ASW assets that were previously an important component. This is partly due to the collapse of the Soviet Union, which removed a great deal of the need for ASW operations, and partly due to budgetary considerations. The mainstay of ASW flight operations, the Lockheed S-3 Viking, has reached the end of its service life, and the last will be retired by early next year. It has already been withdrawn from carrier squadrons.



S-3B Viking launching from USS Abraham Lincoln


At present no replacement aircraft is planned. This leaves a potentially serious gap in airborne ASW defenses. Stopgap measures could include the deployment of shore-based ASW aircraft such as the Lockheed P-3C Orion or its pending replacement, the Boeing P-8 Poseidon, and assigning nuclear-powered attack submarines to protect the carrier battle group. Carrier air wings will deploy the new MH-60R variant of the SH-60 Seahawk helicopter, shown below, in the ASW function.




However, no helicopter has the speed, range or weapons carrying capability of the S-3. This is likely to remain a weakness in the Carrier Air Wing, and if the submarine threat increases, it may have to be addressed by a new aircraft in future. There have been suggestions that a new version of the V-22 Osprey might be developed for the purpose. This would have the advantage that it could also operate from amphibious assault ships, as it would not be restricted to catapult- and arrester-gear-equipped carriers for launch and recovery.

The S-3 also served as an in-flight refueling tanker for strike aircraft, carrying fuel in a 'buddy store' beneath its wings, as shown below.




With the S-3 leaving service, a replacement tanker was needed. This capability was incorporated into the new F/A-18E/F Super Hornet, which can carry a similar 'buddy store' to refuel its fellow strike aircraft, as shown below.




The future of the USN's strike aircraft is presently under scrutiny, and a number of interesting developments should be examined. Let's begin by stating the single most critical problem: modern combat aircraft have become extremely expensive. New technologies and materials are part of this, of course, but so is inflation - not to mention plain, downright greed among suppliers. To illustrate, consider these actual prices for USAF front-line aircraft:

  • The P-51D Mustang fighter of World War II cost $50,000 in 1945 ($573,173 in 2007 dollars, adjusted for inflation);
  • The F-86E Sabre of the Korean War cost $220,000 in 1952 ($1,711,206 in 2007 dollars);
  • The F-4E Phantom II of the Vietnam War cost $2,400,000 in 1965 ($15,708,972 in 2007 dollars);
  • The F-16A/B Fighting Falcon of Operation Desert Storm cost $14,600,000 in 1992 ($21,451,295 in 2007 dollars);
  • The F-35A Lightning II's unit cost when it enters service in 2011, according to the USAF's 2008 budget projection, will be $83,000,000.


Incredible, isn't it? The front-line fighter/bomber of 1945, even allowing for inflation, cost less than one per cent of the price of the front-line fighter/bomber of 2011! The front-line fighter/bomber of Operation Desert Storm in 1992 cost less than a fifth of the price we'll pay for its replacement, the F-35, in 2011.

Faced with this cost inflation and the changing threat environment, the USAF stopped buying previous-generation strike aircraft in the 1990's, pinning its hopes on the Joint Strike Fighter (JSF) project (of which more later). However this program is greatly over-budget and very late. The result is that the USAF's existing aircraft are getting progressively older and more expensive to maintain. In addition, budgetary constraints mean that it won't be able to buy enough new aircraft fast enough to replace its legacy fleet, as older aircraft reach the end of their useful lives. This is likely to cause crippling constraints on its operational flexibility over the next two decades.

The US Marine Corps has also 'bet the farm' on JSF, looking to it to replace its F/A-18 Hornet carrier-based aircraft and also its AV-8B Harrier II vertical take-off and landing aircraft, deployed on amphibious assault ships and at forward air bases. Like the USAF, it stopped buying 'legacy' aircraft, preferring to wait for the JSF, and its existing aircraft are also getting old and tired. Whether or not they'll remain operationally effective until they can be replaced is an open question, particularly given the heavy demands on them (and USAF planes) for operations in Iraq and Afghanistan over the past few years.

The USN took a rather different approach to its sister services. It had proposed the Advanced Tactical Aircraft project in the 1980's, leading to the design of the A-12 Avenger II strike aircraft.



Artist's concept of A-12 Avenger II


It was planned to buy 620 A-12's for the Navy and 238 for the Marine Corps. However, due to enormous cost overruns, this program was canceled in 1991 before a prototype was built.

The Department of Defense mandated that the USAF, USN and USMC seek a common solution to their future strike aircraft needs. This evolved into the Joint Strike Fighter Program, which was eventually won by the Lockheed Martin X-35. This aircraft went on to be developed into the F-35 Lightning II, which is nearing production status.

The Lightning II will be built in three versions. The F-35A, shown below, is a conventional takeoff and landing version for the USAF, using existing airfields.




The F-35B is a short take-off and vertical landing (STOVL) version for the US Marine Corps, which can operate from conventional airfields, rudimentary forward air bases, aircraft carriers, and amphibious assault ships, replacing both the F/A-18A/B/C/D Hornet and the AV-8B Harrier II. It will have a smaller internal weapons bay and reduced internal fuel volume compared to the F-35A, due to the space taken up by the lift fan and other specialized machinery. The X-35B JSF prototype is shown in hovering flight below.




The F-35C, the first of which will fly next year, will be a carrier-borne variant for the USN. It will have a larger, folding wing and larger control surfaces for improved low-speed handling, and stronger landing gear, an arrester hook and catapult launching capability, all required for carrier operation. Its structure will be strengthened to withstand the stresses involved. The graphic below shows the three versions from above. The larger wing and control surfaces of the C model are clearly visible.




The F-35 will be able to carry a wide variety of weapons, both US and foreign, as shown in the graphic below. Several foreign air arms have joined the program.




The USN committed itself to the JSF program, and is scheduled to buy 480 F-35C's for its carrier air wings, replacing Boeing F/A-18A/B/C/D Hornet models. The USMC will buy 340 F-35B's to replace its Hornets and Harrier II's. (These figures are, of course, current proposals: they may change in the light of future budgetary restrictions.)

However, the USN did not make the same decision as the USAF and USMC, abandoning the purchase of other aircraft while waiting for the outcome of the JSF program. Instead, it persuaded Congress to approve the development of the Boeing F/A-18E/F Super Hornet, portraying it as an evolutionary development of the earlier F/A-18A/B/C/D models. However, whilst it's visually similar to the earlier Hornet, the Super Hornet is in fact an almost entirely new aircraft, 20% larger and much heavier than its predecessor, and carrying 33% more internal fuel. As one commentator has noted:


In terms of broad comparisons, the F/A-18E/F most closely compares to the late model F-15 variants. While it does not have the supersonic optimised wing and top end BVR combat and supersonic agility performance of APG-63(V)2 phased array fitted F-15C models, it has a more recent avionic package, radar cross section reduction measures absent on the F-15 and a very modern defensive EW package. In most key respects, the Super Hornet is a substantial improvement over the established F/A-18A-D models, especially in combat radius performance. While the aircraft is frequently criticised for not offering a dazzling supersonic agility and thrust/weight performance increase over the baseline F/A-18C, this was not a primary design objective. Rather, the aim was to provide a low risk near term growth aircraft exploiting the established technology investment in the F/A-18C, and utilising newer technologies such as RCS reduction, integrated MIDS datalink and advanced countermeasures to improve the aircraft's survivability and lethality without the cost penalties of a clean sheet new design.


The Super Hornet has replaced the Grumman F-14 Tomcat and Grumman A-6 Intruder in USN service, and is also replacing some earlier-production Hornets. It continues in production, and a new version, the EA-18G Growler, pictured below, has begun to replace the EA-6B Prowler in the electronic warfare role. Note the aerial bulges on the vertical surfaces of the tail, and the under-wing and wingtip electronic equipment pods.




The Super Hornet, while very capable in many ways, does have certain disadvantages. Its power, range and maneuverability are inferior to a likely opponent, the Russian Sukhoi Su-27 Flanker family of fighters, which is in widespread service. One commentator summarizes the situation as follows:


In conclusion, the Flanker in all current variants kinematically outclasses the Super Hornet in all high performance flight regimes. The only near term advantage the latest Super Hornets have over legacy Flanker variants is in the APG-79 AESA and radar signature reduction features, an advantage which will not last long given highly active ongoing Russian development effort in these areas. The supercruising Al-41F engine will further widen the performance gap in favour of the Flanker. What this means is that post 2010 the Super Hornet is uncompetitive against advanced Flankers in BVR combat, as it is now uncompetitive in close combat.


Whilst the above comment may be true, it's not exactly fair to the Super Hornet, which was never designed to be an air superiority fighter. The Su-27, on the other hand, was designed to counter the USAF F-15 Eagle. The Super Hornet is multi-role, operating as both fighter and strike aircraft. Inevitably, it will perform less well in the dedicated air superiority role than an aircraft optimized for that purpose. In a combat scenario, it's likely that the USN would try to keep its Super Hornets out of dogfighting range of opponents like the Su-27, preferring to engage them at long range with missiles.

The rest of the USN's F/A-18A/B/C/D Hornet aircraft will be replaced over time by the F-35C Lightning II. This aircraft is optimized for the strike role, with a secondary capability to take on enemy aircraft. It has the advantage of utilizing stealth features in its design and construction, making it much more difficult for an enemy to detect and engage it. However, those same stealth features are an untried quantity in a maritime operating environment. The USAF has found that maintaining the stealthiness of its F-22 Raptor air superiority fighters is causing an enormous maintenance overhead. Since the F-35 uses similar stealth technology, will this also affect its operations? This is of particular importance in the corrosive salt-air environment, close quarters and hard-pounding takeoffs and landings encountered aboard an aircraft carrier. Will a 'stealth' aircraft remain 'stealthy' under such conditions? This remains to be seen.

The US Marine Corps will also be operating the F-35, in its B version, equipped for short takeoff and vertical landing. This may cause some interoperability problems on USN carriers. The USN's F-35C will have a longer range, and be capable of carrying more ordnance, than the USMC's F-35B. If they are to operate in the same Carrier Air Wing, this will require allowances to be made for the latter aircraft, which might be difficult under operational conditions. On the other hand, without the F-35B, the USMC would lose the ability to operate its aircraft in support of its ground forces from amphibious assault ships and unprepared forward air bases. The trade-off will have to be accepted - or the Marines may end up buying some F-35C's instead of a full fleet of F-35B's.

The USN currently has no air superiority fighter like the F-22 Raptor in its inventory, and none is in prospect. There were plans in the 1990's to adapt the F-22 to carrier operations, but these were abandoned due to complexity and expense. Will the lack of such a dedicated fighter aircraft be a problem, or will the F/A-18E/F and F-35C be able to deal with any enemy air threat? This question can only be answered in wartime operations . . . which we hope won't be necessary. However, the lessons of history teach us that such hopes are unlikely to be fulfilled.

The F-35 program is currently running years behind schedule and billions of dollars over budget. Whether or not the aircraft will perform as promised is still uncertain. Indeed, in an attempt to save money, the testing that would normally take place prior to operational deployment won't be completed until almost 300 aircraft have already been built! If any major flaw is discovered, all those planes already bought will have to be modified at great expense, and the operational effectiveness of all three US air services will be in serious danger.

Faced with this uncertainty, it's clear that the USN's strategy of continuing to purchase F/A-18E/F Super Hornets is a wise one. The USAF is already in an extremely difficult situation, because it halted purchases of 'legacy' aircraft in the 1990's to wait for the F-35. Given the delays and cost overruns in the latter program, it now can't buy enough F-35's quickly enough to replace its existing strike aircraft as they reach the end of their service lives. It may end up with a shortfall of several hundred aircraft for several years. The USMC may face the same problem in replacing its older F/A-18A/B/C/D Hornets and AV-8B Harrier II's. The USN may face a similar difficulty as its F/A-18A/B/C/D Hornets reach the end of their service lives, but because it's been steadily bringing Super Hornets into its inventory, the scale of the problem will be much smaller.

The USN is also considering what will replace the Super Hornet in due course. Several years ago it launched the F/A-XX program to assess its future combat aircraft needs. Many observers have questioned why this investigation was necessary at so early a stage. One simple answer might be that the USN saw the problems developing in the F-35 program, and realized that it needed a backup plan!

Be that as it may, the F/A-XX investigation dovetailed neatly with the Defense Advanced Research Projects Agency (DARPA)'s Joint Unmanned Combat Air Systems, or J-UCAS program. This was launched in the 1990's to investigate future unmanned combat air vehicles for the USAF and USN. Two companies built prototypes for testing. Boeing produced the X-45:




and Northrop Grumman produced the X-47A.




In the Quadrennial Defense Review of 2006, it was announced that the J-UCAS project had been terminated. The USAF would proceed with the development of a new generation bomber aircraft (whether piloted or not was to be investigated). The USN decided to pursue what had already been learned with J-UCAS, and contracted with Northrop Grumman to develop the X-47B as a demonstrator, to show what a a future naval Unmanned Combat Air System might look like. Progress has been steady, and the prototype X-47B was rolled out in California just last week.



X-47B rollout, December 16th, 2008


The X-47B is unlikely to go into production in its present form. However, the eventual production version may be very similar. The demonstrator is a very large aircraft, with a wingspan of 62.1 feet (compared to the F/A-18's wingspan of 44.7 feet). The wings fold to 30.9 feet for storage in an aircraft carrier's hangar. It's powered by a Pratt & Whitney F100-220 turbofan developing almost 18,000 pounds of thrust. The demonstrator also incorporates a full weapons bay, of similar size to that on the F-35. It's scheduled to make its first landing on an aircraft carrier in 2011.



Artist's impression of X-47B on carrier deck


The USN has progressively refined its requirements for the technology demonstrator. From being a primarily reconnaissance-oriented airframe, a strike requirement was added, and now autonomous air-to-air refueling is also to be demonstrated. The X-47B will land and take off using arresting gear and catapults in the same way as piloted USN aircraft. A major part of the demonstrator's task will be to determine whether unmanned aircraft can maneuver around the deck of an aircraft carrier without causing damage to other aircraft, or injury to crew members.

Furthermore, the X-47B is a fully stealthy design, without a tail. This is far harder to detect than an aircraft with vertical or near-vertical surfaces. It thus becomes a natural candidate for further development into a fully-fledged strike aircraft. If a tailless design, which is inherently unstable in flight, can be sufficiently developed to automatically land on an aircraft carrier without problems, this will usher in a whole new era of shipborne aviation.



Artist's impression of X-47B in flight


The two video clips below show how the X-47B (and its operational successor) may function in an operational environment. You'll have to excuse the breathless hype of the commentator, which is completely unnecessary - but then, that's show business!








Ironically, the X-47B may also be helping the USAF, despite the demise of the J-UCAS program. As one journal has pointed out, there is evidence suggesting that Northrop Grumman may already have received a secret contract to develop the USAF's new bomber. (It had earlier suggested an XB-47C development, much larger than the X-47B, with a heavier payload.) If that's the case, it's inconceivable that the two projects will go ahead at arms length from one another. It's likely that each will learn from and influence the other. The USAF has indicated that its next-generation bomber will be required in the 2017-2020 time frame, and the USN wants its next combat aircraft to enter service in 2020-2025, so there's also an approximate fit in terms of timescale for development.

We've already spoken of the Grumman E-2D Advanced Hawkeye aerial warning and control aircraft, which is currently under development. Below is a picture of one of the prototypes.




Both the F/A-18E/F Super Hornet and the F-35B/C Lightning II will have full datalink capability with this aircraft, and all three of them with the carrier and its escorts. In effect, any aircraft or ship will be able to convey to any other what its sensors are picking up, and any of them will be able to provide guidance to weapons launched by any other. Any future production version of the X-47B can be expected to have the same capability when it enters service.

The current carrier on-board delivery (COD) aircraft is a derivative of earlier models of the E-2 Hawkeye, namely the C-2A(R) Greyhound.



C-2A(R) Greyhound with E-2C Hawkeye


39 Greyhounds were delivered during the 1980's, and continue in service. They are unlikely to need replacement soon: and since a new generation of Hawkeyes is about to enter service, it's likely that their basic structure could be adapted to provide a relatively low-cost Greyhound replacement as well, if necessary.

The USN's helicopter requirements appear to be adequately met at present, and the USMC is bringing several new types of helicopter into service. The only gaping holes in the USN aircraft inventory are a dedicated carrier-borne long-range ASW platform to replace the S-3 Viking (which might be met, if necessary, by a new version of the V-22 Osprey, as speculated earlier), and a carrier-borne air superiority fighter, which may be less important in a stealth combat environment. As one commentator has pointed out:


No matter how good a conventional fighter is, and how good its missiles and sensors are, an engagement flown against a stealthy fighter aircraft is a no win proposition. The whole engagement can be summarised as "Deedle, deedle, deedle, BANG!". Your warning receiver blares away, you crank your head around to figure out what is happening, and you die as the inbound missile blows you to little pieces. It is indeed as simple as that. Situational awareness is everything in the first-shot-is-the-killing-shot game, and stealth takes away that situational awareness completely.

. . .

With a stealthy air superiority fighter, an opponent ... is disadvantaged in reaction time in every situation, and if the pilot of the stealthy fighter exploits his advantage systematically, the conventional fighter will lose almost every time.

There is no historical parallel for this. Therefore, the established doctrine for air combat tactics is largely obsoleted. Only should the pilot of the stealthy fighter choose to be drawn into a turn-and-burn dogfight, or do so by poor choice of engagement geometry, does the conventional fighter have a chance of success in the engagement.

Therefore, trivial comparisons of manoeuvre performance between conventional and stealthy air superiority fighters are quite meaningless. Capability can only be measured in the context of a suitable air combat doctrine for the stealthy fighter. Should this doctrine be designed to exploit stealth to its fullest, then the conventional fighter will suffer overwhelming losses in almost any scenario.

A US observer commented some years ago that stealth was a "zero-sum game". There is only one winner in an air battle between a force of stealthy fighters and a force of conventional fighters. Stealth will rule the air battle.


If the F-35 can provide this stealth advantage in the air battle, and if the successor to the X-47B can improve on it, then the USN may not need a dedicated air superiority fighter at all. The advent of directed-energy beam weapons on board ship, as noted earlier, might also render moot the need for an air superiority fighter. If enemy aircraft, missiles and bombs can be shot out of the sky with impunity whenever they come within range of a carrier task force's sensors, the whole air-to-air combat equation changes out of all recognition.

This leads to the question of what potential enemies might do to disrupt carrier air wing operations. There are two obvious possibilities. One is electronic warfare. If an enemy can disrupt the datalinks between aircraft and their ships, their interlinking defenses fall apart, and they all become vulnerable. However, the USN is probably far more advanced in this field than any adversary at this time, and it's working hard to maintain its lead.

The second, much more serious possibility is the use of nuclear weapons against the carrier task force. These don't have to score a direct hit to inflict heavy damage, and the electromagnetic pulse caused by their detonation will almost certainly disrupt all electronic equipment on the ships and their aircraft. With the proliferation of nuclear weapons around the globe, such an attack is no longer inconceivable: and a rogue nation launching it might hope to avoid nuclear retaliation by pointing out that it had used them against a legitimate military target, not involving civilian property or casualties. Given that, the USA might find it legally and politically difficult to respond in kind. Perhaps the only defense against such an attack will be to ensure that no aircraft, ship or missile gets close enough to the carrier task group to pose such a threat.

The USN's biggest single problem in the short term is likely to be, not enemies, but finances. Its ships are enormously expensive (the first of the Ford class carriers is currently expected to cost $8.1 billion in FY08 dollars, including initial development costs for the class). Add to that the cost of modern aircraft (about $55 million apiece for F/A-18E/F's, at least $83 million each for F-35C's, and who knows how much for the successor to the X-47B?), and the budgetary picture looks very bleak. It may be that the USN will not be able to afford as many aircraft carriers and Carrier Air Wings as it would like. On the other hand, if its operational responsibilities remain unchanged, it can't afford to make do with less. This conundrum will have to be resolved, one way or another, and my bet is that the budget will win. I expect the USN will have to deploy fewer large aircraft carriers in future, whether it likes it or not.

There are those who argue that smaller aircraft carriers, sized closer to current USN amphibious assault ships, would be a viable way to maintain carrier numbers. However, the USN points out that smaller ships could not carry a balanced air wing, as larger carriers can. Examination of the smaller aircraft carriers of other nations, current and planned, bears this out. Let's look at a few examples.

The Royal Navy's proposed Queen Elizabeth class carriers, yet to be built, will weigh 65,000 tons at full load and carry 40-50 aircraft.



Proposed layout of Queen Elizabeth class carrier


The Royal Navy's present Invincible class 'carriers' (20,700 tons), which are less than half the size of USN amphibious assault ships, can only operate about 20 aircraft.




HMS Illustrious (Invincible class)
with USS John C. Stennis (Nimitz class)


Neither the Invincible nor Queen Elizabeth classes has or will have catapults or arresting gear, so all aircraft mut be vertical- or short-take-off and landing variants, which limits their warload and endurance. The Queen Elizabeth class will have provision to fit catapults and arrester gear at a later stage, if operational considerations require them, and funds are available to buy them and aircraft to use them. However, given the lessons of history, the latter is questionable.

The French aircraft carrier Charles de Gaulle weighs 42,000 tons at full load, and carries up to 40 aircraft.



Charles de Gaulle (right) with USS Enterprise


The Russian aircraft carrier Admiral Kuznetsov weighs 55,000 tons at full load, and operates up to 40 aircraft, over half of which are helicopters. She has arresting gear, but no catapults. Her aircraft must take off under their own power, using a bow 'ski-jump' to assist them. This means they cannot do so carrying a full load of munitions or external long-range fuel tanks. (Operations aboard this carrier, including video, were discussed in Weekend Wings #5.)



Admiral Kuznetsov


The USN's current Carrier Air Wings would have to be cut in half to fit onto smaller carriers like these, thereby losing a great deal of their striking power and flexibility: and there's no guarantee that the smaller ships would be all that much more cost-effective to build and deploy. (For example, the present estimated cost of two Queen Elizabeth class carriers for the Royal Navy is about $6 billion, at current exchange rates, and this is almost certain to rise significantly by the time they're completed.) Certainly, such ships could not be powered by nuclear reactors at such prices - and nuclear power will be essential to generate enough electricity for future beam weapons and other requirements. It's therefore unlikely that the USN will move away from its present large-carrier doctrines.

However, we may see a development of the air divisions assigned to amphibious assault ships. It's not impossible that the USMC could deploy more F-35B's to them, displacing some of the helicopters currently carried, to provide more of a strike force from these platforms. It might even be possible for the next-generation America class amphibious assault ships to be more optimized for the air support role. That might imply a task force of an aircraft carrier with up to four Navy F-35C squadrons, plus an amphibious assault ship with one or two Marine F-35B squadrons. The F-35C's could handle the longer-range missions, assisted (and perhaps eventually supplanted) by the production version of the X-47B, while the Marine F-35B's could handle combat air patrols over the fleet, and move in to support their forces on the ground during and after a landing, when the longer-range aircraft would have taken out most of the initial high-priority targets.

Alternatively, some components of the present Carrier Air Wing could be displaced to other ships. Helicopters, for example, could be moved to an amphibious assault ship, or to a new design of helicopter carrier based on a fast supply ship hull. This would free up space on the aircraft carrier to carry more strike aircraft. Marine F-35B's are also versatile enough to be moved to new platforms in this way, if required. That, in turn, might make possible the intriguing prospect of a naval squadron with two amphibious assault ships. One would carry up to three squadrons of F-35B's, giving significant striking power: the other would carry helicopters and transport aircraft. In effect, the approximate equivalent of a carrier air wing would be spread over two ships. This might be of interest in littoral operations, where a large nuclear-powered aircraft carrier is simply too vulnerable to put at risk.

The next few years will be very interesting for carrier-borne aircraft operations. Chinese naval officers have spoken of wanting up to six aircraft carriers; India is building up to a fleet of three of them; Britain wants its two new Queen Elizabeth class vessels, and France may build a similar vessel to accompany Charles de Gaulle; and other nations may well try to acquire smaller aircraft platforms, similar in size and capability to Britain's Invincible class. The missile threat will continue to proliferate and become more sophisticated, as will the submarine menace.

It's going to be interesting to see what happens.

Peter

5 comments:

Roger said...

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Joe said...

One threat that you did not seem to mention is medium range ballistic missiles. China has apparently demonstrated some effort in targeting and attacking ships at sea. This is something the navy can defend against with missile defense system, however the important part of this attack is that it can be at much longer ranges, than the other missiles attack you have mentioned.

Cargosquid said...

Wow. This is an excellent piece of work.

While its true that one carrier group is vulnerable, the nation that fired on the carrier will quickly find itself under attack by follow up forces. Do the countries that threaten the carriers have enough to withstand that? And are they will to lose their military infrastructure?

Xavier said...

Peter, I'll speak as a former US Navy man here. You are looking at equipment. Wars and conflicts are not won with equipment. Yes, a ship, and even a carrier or two may be sunk.

Guess what? US Sailors are fighting men too. We know going in that we are likely to die for our country, the same as a soldier or Marine. We often do. Even in peace time. We are the tip of the US spear. When something happens, the Navy responds, and the men on those ships may suffer for it. It goes with the job, just like getting shot at goes with the job of a soldier or Marine.

Can a carrier, or even a frigate survive a missle strike and keep in the fight? Yes. The difference is training.

One of the men I served under, Capt. Arthur K. Cebrowski was a huge proponent of smaller carriers such as the carrier he and I served together on, the USS Midway. More small targets with the same capability means less big targets and greater flexibility. The USS Midway and CVW5 led the other carriers and air wings in Desert Storm with sorties, bombs on target, and other statistical criteria.

What could not be assessed is we had a crew far better prepared than stateside carrier groups. We were forward deployed out of Yokosuka in a mission of deterrence on that side of the world. When we left port, it was on a war footing every time, every day. Nine month IO cruises were routine. We never went below condition X-Ray. When we sailed, we always had alert fighters ready and a CAP in the air.

In 2001, Cebrowski went on to the Office of Force Transformation as a Vice Admiral. He tried his damnedest to push for more, smaller carriers. He had seen how a little WWII battleship transformed into a carrier in midconstruction had whooped the rest of the Navy's big boats through the effectiveness of the crew, with real ordnance on target. Cebrowski was blocked right and left in his efforts. The top brass of the US Navy wanted big ships to feed their own egos. The few, the egotistical, the great big freaking targets.

Cebrowski knew though, if the United States did go to war with a protracted naval campaign, there would be little choice but to build them fast, build them small, and build a lot of them. Dispersion of forces works.

In the end though, naval battles are not won through equipment. They are won through stategy, tactics and daring. It has always been so. In the next naval campaign, it will be so again.

And don't ever count out the silent service, submarines.

Tommy Paine IX said...

While, ceterus parabus, the Su-27 is a more capable fighter jet than the Super Hornet. However things are not parabus at all in terms of training and tactics. About the only country who spends as much time & fuel on honing their pilots' flight skills is Israel. Folks who're trained to follow doctrine and to worry that deviations from the norm will bring unwelcome attention from the Zampolit are going to be in real trouble against pilots trained to get inside the other guy's OODA (Observe, Orient, Decide, Act) loop and stay there. It's as bad, or worse, than going up against stealth fighters with non-stealthy ones.