Technology Explained-USN Tactical Aviation Pt I

The US Navy is the only force capable of keeping the Western world’s vast sea lanes open in the event of any major conflict,just as it is the only force capable of power protection in those parts of the world, where forward basing facilities are unavailable for Allied land based tactical aircraft. The ability to position a sizeable tactical air arm anywhere in the world, within days of notice, is a major deterrent to many otherwise ill behaved Third World nations. The result of this deterrence is a very false sense of security in the minds of many Western politicians, who repeatedly fail to appreciate the alternatives. The incompetence of the Iraqis in the recent Gulf War has only served to reinforce this unrealistic perception in the minds of the ignorant.

US Carrier Tactical Aviation – A Recent Perspective

The force structure of the USN’s current carrier based (CV) air arm traces its origins to the late 1950s and early 1960s, when a series of key developments took place. One of these was the construction of a series of large nuclear powered attack supercarriers (CVAN), supplemented by a series of somewhat smaller but no less potent conventional attack carriers (CVA). During the fifties and sixties the USN saw its principal roles in maritime supremacy and long range power protection. the latter largely in support of Allied amphibious operations. This philosophy grew from the experience gained during the Pacific campaign and the subsequent Korean War, and the composition of the typical carrier air wing of the period reflected this.

Another major development was the implementation of Soviet plans to provide the capability to cripple Western shipping lanes in the event of war. This was to be achieved by the application of the world’s largest submarine force, supported by long range strike aircraft flying from strategically located forward bases. It is worth noting that some of the most concentrated subversive operations by Soviet intelligence were specifically targeted at installing pro-Soviet governments in nations which were geographically positioned to cover key shipping choke points. Korea, Cuba, Vietnam, Egypt, Yemen, Ethiopia, Chile and Angola are sad evidence of a clearly defined grand strategic objective which appears to have eluded the comprehension of a great many Western observers, analysts and politicians.

The Vietnam air war and its practical lessons were the final development of the period which shaped the path which was ultimately taken by America’s naval aviation. Vietnam saw the USN fight medium altitude visual dogfights against nimble gunsonly dogfighters while flying strike missions into the world’s most dense air defence system, where some areas had thousands of barrels of AAA per square mile.

The early sixties saw the deployment of a number of key aircraft types which were to play a major role in the following decades, influencing tactical aviation throughout the Western world.

The foremost of these must be the McDonnell F4H-1 Phantom II, a large twin engined all weather (ie IFR) interceptor, armed with AAMs and equipped with a powerful Al radar set. Designed for a 450nm tactical radius on internal fuel alone, the Phantom outranged most of its potential opponents, which it could outclimb, out-accelerate and outreach with its radar/missile suite. The F-4’s superlative payload range and excellent handling characteristics saw its application in the strike role, and it became the first true fighter-bomber of the period. The Phantom’s contribution to Western tactical aviation is one with few parallels.

What is less known is that the USN had concurrently sought to deploy together with the Phantom another fighter, the single engined F8U-3 Crusader 111, a derivative of the existing Crusader. USN policy at that time required that the fleet carried two alternative fighter types, to ensure that serious problems with either of the two would not leave the fleet without top cover. The F8U-3 was a single seat, all weather fighter powered by a single 25,000lb class J75 afterburning turbojet. While it used a thin two position wing with flap blowing, like its ancestor, it also employed two large ventral fins which would swing from horizontal position at low speeds to almost vertical at Mach 2 class speeds. Typically armed with 3 AIM-7 radar guided AAMs, one semi recessed on the ventral centreline, the remaining two semi conformally mounted on the lower fuselage sides, the F8U-3 is said to have been faster, more manoeuvrable, cheaper and longer” legged than the larger Phantom. Given the success of earlier Crusader subtypes in Vietnam, demonstrating a consistently better kill ratio than the F-4, the F8U-3 would have been the scourge of the NVAF were it deployed. This was not to be, as in 1958 the politicians ruled that the USN must choose one of the two fighters, so the Phantom was selected largely due to its 2 man crew and thus better capability in the all weather fleet defence role.

The USN’s need for long range all weather fleet defence was a major factor in this decision. The emerging threat of the Tu-22 Blinder and later bombers armed with Mach 3AS-4 Kitchen missiles prompted the USN to initially seek an all weather missile platform armed with long range AAMs. This aircraft was to have been the Douglas F6D, a two seat side-by-side 50,000lb class twin turbofan subsonic missile platform. Powered by a pair of TF30 fans, it would use its large fire control radar to target its payload of Bendix Eagle two stage Command Link/radar guided AAMs. Designed for endurance, the Missileer/Eagle system divorced all weather fleet defence from the air combat manoeuvring role. This specialisation would allow the air superiority fighters to be smaller and more agile single seat aircraft, inherently more suitable for dogfighting.

Again this was not to be Robert McNamara, the then new US Secretary of Defense, very promptly killed off the Missileer in favour of his pet project, the multiservice TFX. The TFX was to become the controversial F-111, an airframe optimised from the outset as a low altitude long range tactical nuclear strike platform for Tactical Air Command. The USAF mission’s mandatory requirements for low level speed and radius performance led to a 70,000lb design weight airframe, too big and too heavy for most of the USN’s carrier fleet. McNamara’s intention, as it appears, was to replace the F-4 with the navalised F-1118 and thus standardise Navy and USAF tactical fighter fleets. The sad story of the F-1118 is covered in substantial detail elsewhere (Coulam’s ‘Illusions of Choice’ contains a superb analysis of the defective decision making processes involved), the result of the mismatched airframe and mission was an aircraft which was marginally usable by 1965, and a USN which was determined to kill the project off.

The Navy had by then concluded, from experience over Vietnam, that air combat manoeuvring performance was still of fundamental importance. If it was to have a single fighter type for fleet defence and power projection, this type would have to offer excellent ACM performance plus the all weather long range weapon system.

The idea of a VFAX multirole fighter was conceived during the early sixties, this aircraft was to replace the F-4 and A-7 in the air superiority and strike roles. The collapse of the F-111B program however left the Navy without a fleet defence missile platform, as a result the VFAX acquired the F-111B’s massive AWG-9 fire control system and payload of associated long range radar guided AIM-54 Phoenix AAMs By 1970 the VFAX had evolved into the VFX which became the Grumman F-14 Tomcat. The F-14 was a very large and heavy aircraft by virtue of its conflicting mission requirements, but offered major performance gains against its predecessors. The USN envisaged three derivatives of the airframe, the interim F-14A with low thrust TF30 engines, the definitive F-14B air superiority fighter, powered by FX (F-15 program) derivative 25,000lb class powerplants and finally the strike fighter F-14C, in turn a derivative of the F-14B fitted with avionics for all weather strike. The F-14C was to have eventually replaced the aging A-6 subsonic all weather strike aircraft The A-6 had itself evolved from a late fifties US Marine Corps requirement for a STOL all weather strike platform, subsequently the Navy included extended strike radius as a requirement and adopted the type as its principal all weather strike aircraft, supplanting the ineffective supersonic A-5 Vigilante, which in turn moved to the photo recce role. While the A-6 was a slower subsonic airframe, it was rugged, highly manoeuvrable and had excellent load carrying characteristics. Equipped with the DIANE (Digital Integrated Attack & Navigation Equipment) nav attack system, a multimode radar and later TRIM (Trail & Road Interdiction Mission) electro-optical sensor turret, the A-6 made a major contribution to the USN’s air campaign against the North Vietnamese. Its then operators could hardly have conceived of its ultimate longevity.

Grumman were almost bankrupted by the F-14A program, given the complexity of the aircraft and the poorly structured contract with the buyer. The escalating cost of the F-14 program also had a profound effect on the planned derivatives. The F-14B was cancelled as was its offspring, the F-14C, the Tomcat having to wait until the 1990 F-14D for its design thrust engines. By the late seventies the USN had a fleet of subsonic all weather strike aircraft derived from a 1958 design.

The cost and size of the F-14, and its commitment to the fleet air defence role, led very soon to the resurrection of the VFAX concept. The Navy had sought replacements for the aging F-4, A-4 and A-7 fleets, aircraft which performed the VFR day strike mission and in the instance of the F-4, the air superiority mission. The DoD initially sought to have the Navy adopt a navalised F-15, the Navy responded with an F-14 stripped of the AWG-9/AIM-54. The DoD bureaucracy eventually prevailed and imposed upon the Navy the NACF (Naval Air Combat Fighter) high-low mix concept it had forced upon the USAF with the LWF/F-16 program to supplement the costly F-15.

At the time a complex series of studies was conducted by the Navy, the DoD and Congress to select the optimal CVW (air wing) structure for the USN. Various mixes of the F-1’4, the VFAX, the NACF, the A-6 and A-7 were evaluated in these studies and it appears that none of the studies produced mutually consistent results. By late 1975 the USN had yielded·and accepted the F/A-18 program, this type being the NACF derivative of the USAF’s Northrop YF-17.

The USN’s principal objections centred upon the NACF’s payload/range performance, which was lower than what the Navy had sought. In practice this meant that a carrier force using the NACF would have to close to shorter range to engage or would have to commit a lot of deck space to tankers. The USN clearly sought a larger aircraft than the F/A-18A, itself quite larger than its ancestor the YF-17. The bureaucracy and politicians however prevailed, and the Navy proceeded with the deployment of the F/A-18 in its then form. The nicest aspects of the F/A-18 were its superlative dogfighting performance and its true multirole capability, although neither of these would have been lost were the aircraft to have been a slightly larger design, as is the current F/A-18E/F.

The argument over combat radius later resurfaced during the F/A-18A’s opeval (operational evaluation) trials, with much heated argument about the aircraft’s ability to match the payload/radius of the significantly slower A-7E.

The demise of the F-14C and the replacement of the F-4, A-4 and A-7 with the short-legged (ie 300nm class) F/A-18A left the Navy with a major requirement for a modern long range all weather strike aircraft. The A-6 was by design one generation behind the USAF’s F-111ND/E/F and NATO’s Tornado IDS, and even ongoing avionic upgrades couldn’t compensate for its basic aerodynamic limitations. The USN had set itself an objective in the post WW2 period of attaining a 600nm over-the-horizon strike capability from a CV. At this radius it is very difficult for an opponent to engage the fleet, this in turn reducing the resources which must necessarily be committed to immediate fleet defence, ie fighters allocated to Combat Air Patrols (CAP) and Deck Launched Interceptor (DLI) duty. The ability to project power via air superiority fighters and strike fighters at extended radii vastly increases the potency of the carrier battle group (CVBG), as more of its complement is available for this offensive mission.

Another major gain from increased CV striking radius is that it vastly complicates life for the defending opponent, whose axes of attack toward the fleet will become increasingly constrained with increasing radius, thus rendering any defensive air strikes predictable in geometry. If threat axes are predictable, SAM firing cruisers and fighter aircraft may be readily concentrated, and concentration of fire is always a winning proposition. With increasing CVBG distance from the defending sides’ coastal bases, the carrier has more space to manoeuvre and this within itself will create more difficulties for the defending side, who must commit larger resources to long range maritime recce missions. The area to be covered by such recce increases with the square of distance, but resources required for maritime recce are proportional to the area to be covered.

To illustrate this with numbers, searching a 45 degree sector out to 300nm requires coverage of about 35,000 square nm, whereas searching the same sector out to 600nm requires coverage of about 141,000 square nm. At 1,000nm this increases to nearly 400,000 square nm. The square law relationshipis mos evident here as a factor of three increase in radius res _ ults in an order of magnitude increase in area coverage required. The defending side must then either acquire more maritime recce aircraft or accept a very low probability of detecting the fleet. While sensors such as OTHB (eg Jindalee) and the RORSATs (Radar ocean Reece SATellite) can offset this advantage, both have their limitations and both may be subjected to standoff jamming by airborne platforms which will reduce their effectiveness considerably.

It is worth noting that the recent Gulf War could have taken a radically different course were the Iraqis to have overrun the Eastern coast of Saudi Arabia, thus preventing the forward basing of USAF and RAF tactical jets. This would have placed far more pressure on the Navy’s CVBGs, which would also have to operate at greater radii from their intended targets in view of forward deployed Iraqi strike aircraft. The absence of the F-15/ AWACS umbrella would have in turn forced the commitment of far more naval fighters to fleet defence. The payload/radius performance of the USN’s tactical jets would have then become a major constraint to operations.

The radius performance of the past two generations of air superiority and strike aircraft underscores this point. The sixties F-4/A-4 mix yielded a radius of the order of 300nm, while the F-14/A-7 mix yielded about 500nm. The long legged A-6 outranged all of these aircraft, and this translated into much better payloads on target at nominal power projection radii. The current CVW composition of 20 x F-14NA+/D, 20 x F/A-18C and 20 (or less) x A-6E is severely constrained by the F/A-18C which unrefuelled reaches to 300nm or so, given catapult launch weight constraints. If the CVBG is to apply its full complement, it will be limited to 400nm or less with F/A-18s refuelled from K A-6D tankers.

The perceived need for in flight refuelling with the existing CVW composition was so great, that the USN had investigated during the late eighties the acquisition of land based Boeing tankers. This in turn led the USAF to evaluate Mk. 32 probe/drogue pods on KC-10 tanker/transports to frustrate this attempted Navy intrusion into sacred air force territory. The USN responded to this by nominating the S-3 Viking as the receiver test platform for these trials; with a high aspect ratio lightly loaded wing the S-3 proved to be very tricky to refuel in the wake of the gargantuan KC-10. T he status of either program is unclear at this time.

As the USN reequipped its CVWs with the F/A-18 during the 1980s, it defined its plans for its new all weather long range strike platform and new air superiority fighter. The strike platform was to have exploited the emerging stealth technologies, while the air superiority fighter was to exploit technology developed in the USAF’s ATF program. The strike platform would have the penetration performance possesed at that time only by the USAF’s secret F-117A, while the air superiority fighter would exploit the supersonic cruise and stealth capability the USAF was specifying into its new fighter.

By the late eighties both programs had consolidated and became the Advanced Tactical Aircraft (ATA) and Naval Advanced Tactical Fighter (NATF). These types were to supplant the A-6E and F-14ND respectively, during the later nineties. The USN had envisaged the deployment of the ATA in the mid nineties, with substantial numbers in service by the turn of the century. As ATA program spending would decline with increasing numbersin service, the NATF would enter development and early deployment with the fleet fully reequipping in the first decade of the next century.

The events of January this year have effectively demolished this long term reequipment plan. 

Part II contains a technical review of the ill-fatedA-12A program and Part Ill reviews the F-140 and F/A-18E/F aircraft and their respective weapon systems.