VFAX
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VFAX for Naval Fighter Attack Experimental was actually two specifications for two US Naval fighter projects. The first was for a low cost lightweight complement for the F-111B which could replace the F-4 Phantom II for air superiority, escort, and ground attack missions in the early 1960s.
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[edit] Overview
VFAX was essentially the Navy counterpart to the Air Force's FX study which eventually led to the F-15 Eagle air superiority fighter. The F-111B had nonexistent rear visibility and was found to be too heavy and ungainly to cope in a dogfight. It was not even slated to carry a simple gun or AIM-9 Sidewinder normally carried by air superiority fighters like the elegant F-8 Crusader. Even the F-4 Phantom II did not achieve the success that the US enjoyed over Korean MiGs. It was thought that a mix of F-111B and lighter advanced fighter bombers could handle all anticipated threats in close and long range combat.
As a company project, Grumman was well aware of the limitations of the F-111B, but their approach to the VFAX was the Grumman 303 design. It essentially transplanted the engines and AWG-9/AIM-54 Phoenix weapons system of the F-111B in an agile airframe with the unlikely wings, landing gear, and intake ducts of the A-6 Intruder. It would have to be capable of defeating Soviet MiG-17 and MiG-19 fighter encountered by Navy pilots after 1965 over Vietnam. After 1967, it would also have to defeat next generation Soviet fighters as well. By 1966, [1] the Navy had been persuaded that a single VFAX could meet the specification if it was large enough to carry the AWG-9/Phoenix weapons system. The VFAX was dropped was quickly dropped in favor of a hastily rewritten VFX specification which was largely built around the 303. The VFX, it was thought, was a better and cheaper alternative to a fleet of F-111B FADF (fleet air defence) dedicated interceptors and lighter fighter bombers. Needless to say, this greatly accelerated the need to cancel the now superflous F-111B.
In 2006, many on internet forums had expressed the common view that loiter, range, approach speed, and fleet air defence were the only design goals for the F-14. However, simhq.com member Julian Data has posted what is evidently the only surviving account of the VFAX specification. When the final classifications of the VAFX/VFX came out, it was composed of the following, with Air Superiority (Visual maneuvering close combat) as the first priority, ahead of FADF.
- Air superiority
- Fleet Air Defence FADF
- Attack Escort
- Air to Ground Attack
- Long loiter time
- Range
- Approach speed to the carrier
[edit] Maneuverability
In order to avoid being forced to accept the FX specification then being developed by the USAF, the Navy insisted on an airplane uncompromised by the air superiority requirements. This was actually a code phrase which meant retaining the primary FADF capability of the relatively heavy Phoenix missile. If the F-14 was created to shoot down bombers, and it was not optimized for maneuvering air combat as the primary design goal, it has even been suggested that the F-14's extraordinary maneuverability is due to the accident of a low approach speed requirement.
However, the Grumman design was able to create a design in which the FDAF and AS requirements did not significantly compromise each other. The F-14 would use a wing sweep program to optimize lift and drag at all combat speeds, twin tails for stability, greatly reduced weight through extensive use of titanium to achieve a better thrust to weight ratio than the F-4, a pancake fuselage for increased lift, a raised tandem cockpit for reduced drag and increased visibility, a gun for close-in fighting, and widely spaced engines for weapons carriage and survivability. Though as the first of a new generation of air superiority fighters, it would be criticized for not possessing the desired 1:1 combat thrust to weight ratio as was intended in the proposed upgraded F-14B and F-14C, it would prove to be competitive in training against a variety of competitors throughout its service life, especially at low speeds with a fully forward wing at full afterburner.
When accepted by the Navy after a competition, the VFAX and VFX would become the F-14 Tomcat, the first dedicated US Navy air superiority design since the F-8 Crusader. The F-14 would be tasked as the Navy's only primary air superiority fighter as well as FADF interceptor throughout its service life. Doctrine would strip the F-14 of any ground attack role until very late in its career, with the retirement of the A-6 Intruder and Air Force deployment of the similar F-15E Strike Eagle.
[edit] Revival
VFAX was revived in the 1970s when it was realized that although the F-14 was smaller than the F-111B, it was still a very large plane. Growth versions had takeoff weights nearly as heavy as the spurned F-111B, and it was a very expensive way to replace all of the attack fighters and USMC F-4 Phantoms, which had passed on the Tomcat's cost. The VFAX would later be folded into the USAF LWF lightweight fighter competition. The Navy would choose the loser of the USAF competition, the YF-17. It was the product of a long evolution of the Northrop Cobra project, which was a radical redesign that used the wings and nose of the tiny F-5 Freedom Fighter as a design starting point. Attracted by the safety and growth potential of two engines, it was developed into the F/A-18 Hornet as the low end of a high low mix. Like the F-4 Phantom II, it would have conformal carriage for the radar guided AIM-7 Sparrow (and later AMRAAM) missiles. In the 1990s, the original Cobra design would be stretched yet again into the heavier Super Hornet. The F/A-18E/F would be deemed by 2006 to have enough capability to replace its senior stablemate, the VFX F-14 Tomcat in the primary air superiority role, along with most other jet combat, EW and tanker support types.
[edit] Irony
Dogged by complaints that the F-18 lacked "legs" or range, the Navy later opted for a growth of the F-18, the F/A-18E/F Super Hornet to replace the A-12 Avenger, which in turn was meant to replace the A-6 Intruder. While there were no precise reasons, the Navy and the Secretary of Defense opted to buy no more new Tomcats or its variants. While the Navy studied a swing wing version of the Air Force F-22, they opted not to develop a direct replacement of the F-14 Tomcat. The fire and forget capability of the new AMRAAM missile would give the Super Hornet much of the capability of the powerful, but old AIM-54 Phoenix system.
Together with the F/A-18A and the anticipated retirement of other aircraft types, Hornets and Super Hornets will take on roles of aircraft since Vietnam of the A-1, A-4 and A-7 light attack, F-8 light, F-4 medium and F-14 heavy fighters, RA-5C reconnaissance, KA-3 and KA-6 tankers, EA-6B jammers, and US-3 ASW aircraft, or just about all jet combat aircraft roles. Since they share many systems, this will be quite an improvement over the logistics nightmare that many wrote of in the 1960s.
The original vision of VFAX was a single fighter which, with a heavy interceptor, could handle all combat roles, with the F-14 Tomcat as the first solution. Ironically, that aircraft has arrived as only slightly lighter Super Hornet, but as a distant descendant of the humble F-5 Freedom Fighter designed in the late 1950s entry level fighter that has grown into a multirole platform heavier than the classic F-4 Phantom, and at 66,000 max gross weight, nearly as large and far more expensive than the F-14 Tomcat. Many analysts rate the combat capability as roughly comparable to its McDonnell Douglas/Boeing stablemate F-15 Eagle.
The JSF is being anticipated as next great lightweight multi-service fighter, and the Eagle is being slated for replacement by the hugely expensive F-22 Raptor, but it may be noted that the Super Hornet, a VFAX plus appears to be an aircraft which, other than considerations of complete performance coverage and cost, could be adapted to most fighter missions of all flying services like the legendary Phantom.
[edit] See also
- Robert McNamara
- Air superiority fighter
- F-111B
- F-14 Tomcat
- F-18 Hornet
- George Spangenberg A head of fighter design at the US Navy for this program
[edit] External links
- George Spangenberg's website
- Modern Marvels DVD Modern Marvels epsisodes interviews engineering manager Bob Kress and test pilot Charlie Brown and other Grumman employees on development of VFAX and VFX F-14 Tomcat as America's first teen-series agile dogfighter.