[2.0] Phantom Variants (2024)

* The Phantom was a step forward in aircraft design, incorporating many newfeatures when it was introduced in the late 1950s. In the following decades,new Phantom variants were developed to enhance its capabilities, as well asadapt it to new roles, such as reconnaissance and defense suppression. Thischapter describes the different variants of the Phantom in US service. A fewother variants that only flew in foreign service are discussed in a followingchapter.

[2.1] F4H-1F (F-4A) / F4H-1 (F-4B) / F-4G (I) / F-4N

* The initial XF4H-1 prototype performed its first flights with J79-GE-3engines, but was then refitted with J79-GE-2s and finally J79-GE-2As,providing 46.0 kN (4,695 kgp / 10,350 lbf) dry thrust and 71.8 kN (7,325 kgp/ 16,150 lbf) afterburning thrust each.

The 19th aircraft built replaced the AN/APQ-50 radar set with the evolvedAN/APQ-72, which had a larger antenna that required fit of a new and biggernose. That gave the Phantom a "droopy nose" appearance that made it lookeven more awkward, and also dictated a new canopy scheme. Earlier aircrafthad a canopy that was flush with the aircraft's spine -- but with the 19thaircraft and every other Phantom ever built, the co*ckpit was raised andbulged to give a better view over the big nose. Forward visibility was stillnot the best and rearward visibility was terrible, though the raised co*ckpitdid also improve the view to the back a bit.

The 46th aircraft introduced fully-rated J79-GE-8 engines with 48.5 kN (4,945kgp / 10,900 lbf) dry thrust and 75.6 kN (7,710 kgp / 17,000 lbf)afterburning thrust each, along with minor modifications to the engineinstallation.

In March 1961, the first 45 Phantoms, following the two XF4H-1 prototypes,were retroactively given the new designation of "F4H-1F", while the others inthis series retained the F4H-1 designation. The F4H-1Fs were all evaluationand test aircraft; none of them ever reached operational service.

Full-production F4H-1s were in service with the US Navy and Marine Corps by1962. In September of that year, the US military adopted a tri-serviceaircraft designation scheme, and the F4H-1F became the "F-4A" and the F4H-1became the "F-4B". A total of 649 F-4Bs was built from 1961 to 1967.

Of total F-4B production, 12 were built with an AN/ASW-21 datalink for anautomatic carrier landing system, along with an "automatic approachcompensation (AAC)" system that performed automatic throttle control oncarrier approaches to ensure constant speed. These aircraft were designated"F-4G", with the first flying in March 1963. The new electronics gear wasfitted in a compartment in the upper forward fuselage, created by choppingoff an edge of the forward fuselage fuel cell.

The F-4Gs went through operational evaluation in Southeast Asia in 1965:1966.They were then returned to the F-4B specification, suggesting that the AACsystem was unsuccessful -- but the F-4G designation would be "recycled" in alater Phantom variant, see below. The new avionics compartment was carriedon to other variants.

* Between 1972 and 1974, 226 Navy and Marine F-4Bs were put through an updateprogram with structural strengthening, new wiring, 30-kilowatt electricalpower generators, and new avionics. The updated aircraft were known as"F-4Ns".

[2.2] F-4C / F-4D

* Robert S. McNamara, US secretary of defense in the Kennedy and JohnsonAdministrations, was very enthusiastic about "commonality" between thedifferent US armed services. He wanted the services to adopt commonequipment to reduce acquisition, logistical, and training costs. In 1961,the word came down that the USAF should evaluate the Navy Phantom. The Navyloaned what would eventually be a total of 29 F-4Bs for the evaluation.

Such attempts to enforce commonality didn't always work out well, partly dueto interservice rivalries, plus the fact that the services sometimesreally did have clearly different needs and requirements. The Phantom,however, worked out very well. The evaluation showed the Air Force that thePhantom, even though it carried the weight of additional gear required forcarrier operations, was a match or more for existing Air Force fighters. TheUSAF would eventually acquire over twice as many Phantoms as the Navy andMarine Corps combined.

In the spring of 1962, the USAF decided to adopt the Phantom, under theinitial designation of "F-110A Spectre", which was applied to the loaned NavyF-4Bs then being evaluated by the Air Force. A USAF-optimized variantactually went into service as the "F-4C", retaining the Navy Phantom name,with the first example of the variant flying on 27 May 1963. 563 were builtto 1966. The F-4C was very similar to the F-4B, even retaining arrestinggear and folding wings, but featured a number of changes:

• J79-GE-15 engines, which were similar to the J79-GE-8 engines used on the F-4B, but were slightly uprated and used a pyrotechnic cartridge starter system, instead of an external compressed-air starting system. This allowed the F-4C to "self-start" and operate from remote airstrips with minimal ground support gear.
• A pop-up boom-type refueling socket fitted on the spine of the aircraft behind the co*ckpit, replacing the F-4B's refueling probe.
• Wider-tread, low-pressure tires, better suited to the relatively gentle landings on ground airstrips, as opposed to the "smackdown" landings on carrier decks. A slight bulge had to be added to the wings to accommodate the tires.
• Dual flight controls. The height of the rear instrument panel was reduced to give the back-seater, known as a "weapons system officer (WSO)" or "whizzo" in Air Force nomenclature, a better forward view. Early on, pilots from other types were used as WSOs, but it proved wiser to train WSOs from the ground up to make the best use of the radar and weapon systems. WSOs were still capable of flying the aircraft to spell the pilot if necessary.
• New avionics, including an AN/APQ-100 radar, an improved version of the F-4B's AN/APQ-72, featuring a better display system; an AN/ASN-48 INS for long-range navigation; an AN/AJB-7 bombing system; and provision for launch of radio-controlled AGM-12 Bullpup radio-guided air-to-surface missiles (ASMs). The Bullpup would not prove a very useful weapon in service.
• Provision for the carriage of two AIM-4 Falcon AAMs on the wing pylons instead of four Sidewinders. That would not prove a good idea either, and the Falcons would rarely be carried.

After the F-4C went to Vietnam in 1965 a number of problems emerged,including fuel leaks and poor tolerance to humidity. A field update programwas implemented to address the problems.

* The F-4C was followed in USAF service by the "F-4D", which performed itsfirst flight on 9 December 1965, leading to initial service deliveries in1966. The F-4D would be the USAF's workhorse over Southeast Asia. 825 werebuilt to 1968.

The F-4D airframe was basically the same as that of the F-4C; the primaryenhancements were in avionics, particularly AN/APQ-109 radar. The AN/APQ-109was an improved, more reliable "hybrid" version of the AN/APQ-100 withsolid-state components in the low-voltage sections. The F-4D also featurednew attack and navigation systems, and uprated 30-kilowatt electric powergenerators.

Since combat experience over Southeast Asia had shown the need for a gun, a20-millimeter cannon pod designated the "SUU-16/A" was hastily introduced, tobe eventually replaced by the similar but improved "SUU-23/A" pod. The F-4Dwas wired for carriage of the cannon pod, and had an ASG-22 lead-computinggunsight fitted for aiming it. Apparently some F-4Cs were also retrofittedto carry cannon pods.

The AN/AAA-4 IRST was deleted in most F-4D production, since it had provenuseless in practice. Confusingly, late production F-4Ds were fitted with thefairing used for the AN/AAA-4, but it contained elements of an AN/APR-25/26radar warning receiver (RWR), not an infrared sensor.

[2.3] F-4E

* Combat experience led to the definitive Air Force "F-4E", which performedits initial flight on 30 June 1967. The F-4E featured:

• Uprated J79-GE-17 engines, with 79.6 kN (8,120 kgp / 17,900 lbf) afterburning thrust.
• A General Electric M61A1 six-barreled 20-millimeter Gatling-type cannon on the underside of the nose, with 640 rounds of ammunition. Fit of the cannon required a new and longer nose, a modified version of the nose designed for the RF-4C reconnaissance Phantom, described below. The cannon pod had been a big help, but it was "draggy" and tended to become misaligned on its stores pylon, making it inaccurate. The built-in cannon was a much better solution. However, early production F-4Es suffered from engine "flameouts", due to ingestion of gases expelled from the muzzle of the cannon; to fix this problem, GE quickly came up with a longer-barreled cannon, which was fitted to a longer cannon fairing with improved ventilation. This fix was retrofitted to earlier F-4E production.
• A solid-state AN/APQ-120 radar. The new radar was much more compact than its predecessors, allowing it to fit to the nose along with the cannon.
• Martin-Baker Mark 7 "zero-zero (zero altitude, zero speed)" ejection seats.
• A tailplane with a fixed slat attached under the leading edge. The slat provided improved control authority at high angles of attack (AOA).
• A seventh fuel cell in the tail above the engine nozzles.
• Manual wing fold, instead of hydraulic fold. The Air Force usually didn't need to fold the wings unless Phantoms were being transported, and so the hydraulic fold was effectively dead weight.

The F-4E became the primary USAF variant, and was also heavily exported, asis discussed later. Including exports, 1,387 were built to 1979.

 ___________________________________________________________________ MCDONNELL DOUGLAS F-4E PHANTOM II: ___________________________________________________________________ wingspan: 11.77 meters (38 feet 8 inches) wing area: 49.24 sq_meters (530 sq_feet) length: 19.2 meters (63 feet) height: 5.02 meters (16 feet 6 inches) empty weight: 13,760 kilograms (30,330 pounds) loaded weight: 28,030 kilograms (61,795 pounds) max speed at altitude: 2,415 KPH (1,500 MPH / 1,305 KT) service ceiling: 16,580 meters (54,400 feet) combat radius: 1,265 kilometers (785 MI / 680 NMI) ___________________________________________________________________

* The F-4E was enhanced during and after its production. One of theparticular limitations of the Phantom was that it had been designed basicallyas an interceptor and strike aircraft, not a dogfighter, and maneuverabilityhad suffered as a result. The lack of maneuverability proved troublesome incombat -- in the worst case, under certain aggressive flight conditions theF-4 could go into a spin that generally required immediate ejection if theaircraft was below 3,000 meters (10,000 feet).

This unpleasant behavior came as something of a nasty shock, since flying thePhantom under peacetime conditions was very straightforward, one pilotcalling it "idiot-proof", and it had an admirable flight safety record. Onceheavily laden with external stores, however, its center of gravity movedbackwards, making it more prone to spins.

In response to the maneuverability problems, a program named AGILE EAGLE wasinitiated, in which the Phantom was fitted with various experimentalaerodynamic modifications. The solution in the end was to fit the wing withleading-edge slats, which extended automatically when the aircraft's AOAexceeded six degrees, and retracted when the AOA went back to four degrees.The slats replaced the leading-edge flaps; installation of the slats requiredremoval of the BLC system. The leading-edge slats were introduced into F-4Esbeginning in mid-1972 and were retrofitted to older aircraft. Beginning thenext year, 1973, F-4Es went through a structural strengthening program afteran F-4E was lost due to a wing structural failure.

The Northrop "Target Identification System Electro-Optical (TISEO)" camerasystem was also introduced in late F-4E production, being retrofitted toolder aircraft as well. TISEO involved a steerable, stabilized telescopiccamera mounted on the left wing, and was used primarily to inspect targetsbefore engaging them. TISEO imagery was displayed on the WSO's radarscope.The camera could be slaved to the AN/APQ-120 radar, and apparently there wasan upgrade that allowed it to be linked to the navigation system to targetflight checkpoints as well. Of course, it was a daylight / clear-weatheronly system. Most export F-4Es were not fitted with TISEO.

[2.4] F-4J / F-4S / ODDBALLS

* The Navy and Marines procured a variant similar to the F-4E, designated the"F-4J", with the following improvements:

• Some new features like those of the F-4E, such as Martin-Baker Mark 7 zero-zero ejection seats; the slatted tailplane; and the number-7 fuel cell. The M61 cannon was not fitted, and in fact no production Navy or USMC Phantoms would ever have built-in gun armament.
• Uprated J79-GE-10 engines, comparable to the F-4E's J79-GE-17, but without cartridge starting.
• Strengthened airframe and landing gear, with Air-Force style tires.
• New avionics, including an AN/AWG-10 fire control system with AN/APG-59 radar; an AN/AJB-7 bombing system; an AN/ASW-25 data-link for automatic carrier landings, developed as a follow-up from the F-4G experiments; and an AN/APR-32 RWR. The AN/APG-59 was a particular step forward, being a solid-state system with multi-mode operation and "look-down" capabilities, allowing it to pick low-altitude targets out of ground clutter.
• An uprated 30-kilowatt electric power generation system.

Three F-4Bs were rebuilt as "YF-4J" prototypes, with the first prototypeperforming its initial flight on 27 May 1966. 522 new-build F-4Js weremanufactured to 1972, following the prototype conversions. A specialversion of the F-4J was proposed for the USMC but not built, thisaircraft being intended to feature an enhanced fire-control system andF-4E-style leading-edge maneuvering slats.

Incidentally, the "F-4F" was a specialized Phantom variant flown only by theGerman Luftwaffe, discussed later; while the "F-4H" designation was not used,since it might have caused confusion with the old "F4H" designation. The"F-4I" designation wasn't used either, since it could be misinterpreted as"F-41".

* Beginning in 1978 248 F-4Js were brought up to "F-4S" standards, withstructural strengthening; leading-edge slats; a substantially updatedAN/AWG-10A radar set and other new avionics; and uprated J79-GE-10B engines,which also featured engine improvements to eliminate the tendency of the J79to leave behind a trail of dirty smoke, a liability in combat. Fit of theleading-edge slats required removal of the BLC system.

* There were also some unusual or unbuilt Phantom variants. The 226thPhantom built was used as an experimental platform. It started life as anF-4B, to be reconfigured as the prototype for several Phantom variants. In1972, it was given a fly-by-wire (FBW) control system, and was later givencanard foreplanes. This aircraft was retired and donated to the US Air ForceMuseum in Dayton, Ohio, in 1978.

In the late 1970s, McDonnell Douglas proposed an air superiority variant ofthe F-4E designated the "F-4T" that would have deleted all gear needed forground attack. Nothing came of the notion.

The most dramatic proposed modification of the Phantom was a "swing wing" or"variable geometry" derivative of the F-4J, designated the "F-4 (FVS)",promoted in the mid-1960s by McDonnell. The wings would be shoulder-mountedand would be able to sweep from 23 to 75.5 degrees. The Navy was very leeryof this idea, since the service wanted a new fighter instead of an updatedversion of an older one, and lobbied successfully for the Grumman F-14 Tomcatinstead.

[2.5] RF-4C / RF-4B / RF-4E

* Although the Air Force had some entirely understandable resistance toacquiring a Navy fighter, after adopting the Phantom the USAF quickly becamevery enthusiastic about the type. Shortly after ordering their firstproduction Phantom fighters, the service decided to acquire a reconnaissancevariant to replace their current McDonnell RF-101 Voodoo. The "recce"(pronounced "rekky") Phantom was originally designated the "RF-110A", but wasredesignated "RF-4C" in September 1962.

The Phantom was adapted to the reconnaissance role through fit of a newforward fuselage to carry cameras and other reconnaissance gear. Initialflight of the first of two "YRF-4C" prototypes was on 8 August 1963. 505RF-4Cs, including the two prototypes, were built to 1974.

The cameras were fitted in a new nose that stretched the aircraft's length by84 centimeters (33 inches). The wing-mounted pitot tube was moved to thenose from the leading edge of the tailfin as well, resulting in a totalincrease in length of 147 centimeters (57.8 inches). As noted, a modifiedversion of this nose was fitted to the F-4E to accommodate the M61 cannon,and resulted in the same increase in length.

The RF-4C's nose featured three camera "stations" that could be configured byground crews with different camera fits:

• "Station 1", or the "forward camera station" was just under the radome and stared forward at an angle. It could accommodate a KS-87 or KS-72 camera.
• "Station 2" was behind station 1, and included a camera port staring downward, as well as camera ports staring off to each side. It could accommodate various combinations of KS-72, KS-87, or panoramic KA-56 cameras in vertical or oblique (angled to the side) mountings.
• "Station 3" was behind station 2, and included two vertical ports. It could accommodate a KA-91 or KA-55A high-altitude panoramic camera; dual KS-87s with different focal lengths; or KC-1A, KC-1B, or T-11 mapping cameras.

In addition to the cameras, the RF-4C carried electronic reconnaissance gear,as well as systems to support the reconnaissance mission:

• A Goodyear AN/APQ-102 "side looking airborne radar (SLAR)" that shot radar beams out to the sides of the aircraft and recorded the echoes on a long film strip, giving an all-weather view of the terrain alongside the aircraft's flight path.

  The AN/APQ-102 also had a "moving target indicator (MTI)" capability that picked out any vehicle moving at more than 9.25 KPH (5.75 MPH or 5 knots) perpendicular to the aircraft's flight path, highlighting the target on the film strip. The SLAR was mounted under the pilot's position, with the SLAR antennas fitted unobtrusively into the fuselage at that location, forward of the engine intake ramps.

• An AN/AAS-18 infrared line scanner was mounted under the back-seat position and stared out of the belly vertically. It recorded infrared imagery on a film strip to provide a thermal map of the terrain below the aircraft's flight path.
• An AN/ALR-17 "radar homing and warning system (RHAWS)" that located, identified, and targeted adversary radar stations, marking them on film imagery. RHAWS antennas were mounted on either side of station 1 and on the wingtips.
• An "auxiliary data annotation set (ADAS)" that marked camera film with such useful data as date & time, radar and barometric altitude, latitude & longitude, heading, pitch, roll, drift angle, and unit identification.
• Two photoflash cartridge dispensers, fitted underneath the fuselage at the tail for night photography.

The RF-4C could also be fitted with electronic intelligence (ELINT) systemscarried in pods on stores pylons.

The RF-4C was not kitted up to get into fights. Fire control systems weredeleted; the recesses for Sparrow missiles under the fuselage were fairedover, since the RF-4C didn't have the radar to guide the Sparrows; and thepilot's weapons sight was replaced by an LA-313 optical viewfinder to helptarget camera shots.

Instead of an AN/APQ-100 radar set, the RF-4C was fitted with a more compactTexas Instruments AN/APQ-99 forward-looking radar set, intended to supportair navigation instead of combat. The AN/APQ-99 provided a ground mappingcapability, along with terrain-following and terrain-avoidance modes. TheRF-4C also featured an improved AN/ASN-56 INS, and a long-range HFcommunications system. Although in Air Force terminology the back-seater wasstill known as WSO, since the RF-4C didn't have any weapons, he was moreoften known simply as the "navigator".

Following the Vietnam War, USAF RF-4Cs were given various upgrades to keepthem up to date, the most important being fit of the AN/ALQ-125 ELINT system.

* The RF-4C's nose and reconnaissance gear was fitted to the F-4B airframe toyield the "RF-4B" for the US Marine Corps, with initial flight on 12 March1965, leading to operational introduction in May 1965. The equipment fitdiffered slightly from the RF-4C's in that the station 2 cameras could berotated in flight.

The RF-4B actually followed the F-4C into service, reversing the usualsequence of subvariant codes. The RF-4B was strictly a Marine machine; theNavy did not use the type since that service had no requirement for it,relying on the RF-8A Crusader and RA-5C Vigilante for the reconnaissancerole. 46 RF-4Bs were built. The last ten were odd hybrids, with theoriginal RF-4B nose, RF-4C fuselage and tail, and F-4J wings. In the lasthalf of the 1970s, the RF-4Bs were given a substantial update under ProjectSURE, involving structural strengthening, new reconnaissance systems, adatalink, defensive countermeasures, and other avionics.

* The F-4E was fitted with a recce nose to yield the "RF-4E". Initial flightof the prototype was on 15 September 1970, and 146 were built, strictly forthe export market. Late production F-4Es had a modified nose that was lessangular than earlier recce Phantoms. RF-4Es also had slight variations inequipment fit for their specific customers.

By this time, the Phantom was properly known as the "McDonnell Douglas"Phantom, since the two companies had merged in 1967. Three decades later,McDonnell Douglas would be bought out by Boeing, but nobody would think tocall an F-4 a "Boeing Phantom".

[2.6] F-4G WILD WEASEL

* The last Phantom was rolled out of the McDonnell Douglas factory at SaintLouis on 26 October 1979, after manufacture of 5,057 of the type there, notcounting 138 assembled or built in Japan, as discussed later. However, giventhe widespread use of the type, that was by no means the end of the story.

One of the nasty surprises encountered by the US military in Vietnam was theeffectiveness of North Vietnamese air defenses, and so developingcounter-defenses was a high priority. One possible counter-defense was a"defense suppression" aircraft that could target air-defense radars andattack surface-to-air missile (SAM) sites, and this led to the "Wild Weasel"series of "defense-suppression" aircraft.

The original "Wild Weasel I" was a modified tandem-seat F-100F Super Sabre,but this aircraft could not keep up with strike packages, and amounted to aproof-of-concept system. It was followed into service by the "Wild WeaselII", a modified F-105F Thunderchief, and then a more optimized F-105Fmodification, the F-105G "Wild Weasel III", which performed the burden ofdefense suppression over North Vietnam.

Late in the war, about 36 F-4Cs were modified to the "Wild Weasel IV"configuration, carrying radar detection and targeting systems along with theAGM-45 "Shrike" anti-radar missile (ARM), which was a Sparrow with aradar-seeking head. The Wild Weasel IV conversion left something to bedesired, and after the war 116 F-4Es were converted into the "Wild Weasel V"or "Advanced Wild Weasel", which was given the "vacant" designation "F-4G".

The nose cannon was deleted, with the space occupied taken up by gear for anAN/APR-38 RHAWS, with 52 antennas littered over the fuselage. Combatavionics systems were retained. The AN/APR-38 could not only locate andidentify radar emitters, it could also target them for attack with ARMs, orcluster bombs and other munitions. At first, the F-4G carried the Shrike,but in the early 1980s this missile was generally replaced by the TexasInstruments AGM-88 "High Speed Anti-Radiation Missile (HARM)", more or less ascaled-up Shrike with a better seeker system. The HARM would become theF-4G's most characteristic weapon.

[2.7] QF-4 PHANTOM TARGET DRONES

* With plenty of retired Phantoms available, it is unsurprising that the typewas favored for conversion into high-performance target drones. Some F-4Bswere converted to "QF-4B" target drones and "DF-4B" drone controllers, and aslater Phantom variants were removed from first-line service, they were oftenconverted to target drones as well, collectively referred to simply as"QF-4s". The conversions cost a few million USD each.

Interestingly, some of the QF-4s retained a piloted capability. This wasbecause test and training scenarios require a high degree of choreography tomake them as realistic as possible, and so pilots had to fly the QF-4sthrough "dry runs" to ensure that all details were considered. The USAFreferred to unpiloted flights using the acronym "NULLO (Not Utilizing LocalLive Operator)", while the Navy more tidily called them "NOLO (No OnboardLive Operator)".

Up to four QF-4s could be flown in formation during NULLO flights. Thedrones did not interact with each other, they were simply commanded to followa specific moving point in space known as a "rabbit", with each aircraftmaintaining a specific three-dimensional offset from the rabbit. Theautopilot system on the QF-4 was very sophisticated; for example, the remoteoperator could land the aircraft simply by giving it a single command toland.

Although missiles used in air combat tests don't usually have combatwarheads, once a QF-4 was used as an actual target in exercises, itspredicted lifetime was no more than four missions. The QF-4 carried aself-destruct system to destroy itself if missile damage failed to shoot itdown, leaving it as a potential threat to populated areas.

The last of 316 QF-4 conversions was delivered in late 2013. By that time,they were nearing the end of their useful lives even as targets, since theywere unrepresentative of any adversary American pilots might face. The QF-4was retired in early 2017, the type having been replaced by the "QF-16",converted from retired General Dynamics F-16A fighters.