The F-4D was an improved version of the F-4C which was better suited to the specific requirements of the Tactical Air Command. Although it was externally almost identical to the F-4C which preceded it in USAF service, it was very different internally.
The F-4D was authorized in March of 1964, and the first example flew on December 7, 1965. Deliveries began in March of 1966. The first deliveries were to the 36th Tactical Fighter Wing based at Bitburg in Germany. It was later followed by the 4th TFW based at Seymour Johnson AFB in North Carolina in January of 1967. A total of 793 F-4Ds were built for the USAF.
The F-4D had the same engines and basic airframe as the F-4C, and had the same internal fuel tankage as that of the RF-4C. The major difference was in the avionics. The most significant change was the replacement of the APQ-100 radar of the F-4C by the smaller and lighter partly solid-state AN/APQ-109A. This was part of the AN/APA-165 radar set which introduced an air-to-ground ranging mode using movable cursors. The F-4Ds fitted with the AN/APQ-109A radar set could be externally distinguished from the F-4C by the presence of a larger radome. However, some F-4Ds were fitted with the AN/APA-157 radar set group similar to that fitted to the F-4C and were hence externally identical to the F-4C.
The undernose pod for the AAA-4 infrared search and track was removed. The Collins ASQ-19 miniaturized communication/navigation/identification suite became standard. The Litton ASN-48 inertial navigation system of the F-4C was replaced by an ASN-63 set, which was upgraded and made lighter in weight. An AJB-7 all-altitude bomb delivery system was provided, which was connected to an ASQ-91 weapons release computer for delivery of laser-guided bombs.
The F-4D retained the AIM-7 Sparrow capability of the F-4C, but it deleted the Sidewinder capability on the inboard underwing pylon in favor of the Hughes AIM-4D Falcon infrared-homing missile. The AIM-4D (originally designated GAR-2B) had a launch weight of 134 pounds and had an maximum effective range of about 6 miles.
Starting with Block 27, the infrared search and track pod under the radome was reinstalled, but not to house the AAA-4 infrared search and track, but rather to carry the forward amplifier and antenna of the ALR-25/26 radar warning system. Later, this system was replaced by APS-107A with fin antennae and ALR-69(V)2 with antennae in the chin pod.
Externally-hung jammers that could be carried included the ALQ-87 FM barrage jammer, the Westinghouse ALQ-101 noise/deception jammer, and the Westinghouse ALQ-119 noise/deception jammer capable of covering three bands.
A multiple ejector rack was provided for the centerline pylon and triple ejector racks were provided for the inboard underwing pylon.
The weapons system officer in the back seat was often given a TV display fed from the seeker of a homing bomb system, initially for the GBU-8 and later for the GBU-15.
For weapons aiming, the F-4C had relied on a fixed sight and a simple chart on which it the image of the target was projected. The operation of this system made accurate bombing very difficult. The F-4D had improved avionics to increase the accuracy of its air-to-ground weapons. These included an AN/ASQ-91 weapons release computer system. This system measured various aircraft parameters such as speed, attitude, and climbing rate, and combined it with radar data on the slant range to the target to tell the bomb when to drop from the aircraft.
Also fitted was an AN/ASG-22 lead computing optical sight with amplifier and gyro. This system was designed to improve the effectiveness of the Phantom in air-to-air combat. The system combined information about speed, air density and angle of attack, and combined it with radar data about the velocity, direction and distance of the target to compute the lead angle needed to score a hit.
From the spring of 1967, the F-4D gradually began to replace the earlier F-4C in combat in Vietnam. It initially appeared over Vietnam with the 8th TFW, commanded by Lt.Col. Robin Olds. The first F-4D MiG "kill" took place on June 5, 1967, when crewmen Maj. Everett T. Raspberry and Capt. Francis Gullick shot down a MiG-17 near Hanoi. The F-4D eventually destroyed 45 enemy aircraft, and the USAF's 3 Vietnam-era aces got their fifth kills in F-4Ds during the Linebacker campaign of 1972. Captain Steve Ritchie of the 432nd TFW got his fifth kill in F-4D number 66-0167 on August 18, 1972.
However, the infrared Falcon proved relatively unsuccessful in air-to- air combat in Vietnam, shooting down only four MiG-17s and one MiG-21 between October 26, 1967 and February 5, 1968. The Falcon was definitely not a good dogfighting missile, having been originally designed back in the 1950s for bomber interceptions. One of the basic problems in using the Falcon for dogfighting was that its aerodynamic design made for relatively limited maneuverability. The moveable surfaces at the end of the four delta wings of the Falcon did not provide sufficient aerodynamic force for the rapid changes of direction that were required to be effective against highly-maneuverable fighters.
The Falcon also proved to be somewhat temperamental in service, requiring a lot of careful setting up and tweaking. In addition, the Falcon had a tendency to cause engine flameouts when fired. Perhaps the most significant problem with the AIM-4D was that its fire control system required 6-7 seconds to actually launch the missile after the firing button was pushed, which is an eternity in a dogfight. The internal systems and aerodynamic surfaces of the Falcon were powered by an internal turbo-alternator and hydraulic power unit which was driven by a gas generator. This system took a few seconds to spin up and take over control from the aircraft fire control system. Also, the analog computers in the fire control system had to calculate several pre-launch attack parameters and pass them along to the missiles' guidance system, which also took a second or two.
Thirdly, the Falcon required a direct hit to explode, since there was no proximity fuse. The leading edges of the four delta wings were made of fibreboard, and the intent was that upon impact the missile would bury itself in the fuselage of the target up to the midpoint of the missile's wing. The fibreboard would then crush, completing a circuit and detonating the warhead. Another problem was that the explosive warhead was quite small, only about 4 pounds.
Consequently, combat pilots in Vietnam were very uncomplimentary about the Falcon. As a result of the barrage of complaints from the field, the Sidewinder capability on the inboard underwing pylons was hastily restored. However, in fairness to the Falcon, virtually ALL air-to-air missiles prove to be troublesome in Vietnam and less deadly to enemy aircraft than anticipated.
In later years, the absence of an internal cannon was seen as a liability in close-in air-to-air combat. The F-4D could carry an external centerline SUU-23 pod containing an M-61A1 cannon, but it was bulky, provided lots of drag which seriously compromised performance, and was rather inaccurate to boot. In addition, the cannon pod took up valuable real estate underneath the fuselage, markedly reducing the offensive load that could be carried.
The Westinghouse AN/ASQ-152(V)-2 Pave Spikelaser target designator was fitted to several F-4Ds. The cylindrical Pave Spike laser designator pod was mounted inside one of the Sparrow missile wells on the fuselage underside. The system used television optics, which made it daylight-capable only. Those Pave Spike aircraft which had the capability of launching the AGM-65 Maverick air-to-surface missile included 66-7509, 7531, 7546, 7634, 7661, 7722, 7746, 8819, and 8821.
The AN/AVQ-10 Pave Knife laser target designator could be carried on the inboard underwing pylon of specially modified F-4Ds. This pod had a stabilized head housing a boresighted TV camera and laser designator. It had a low-light television system, which made nighttime missions theoretically possible, although it is not certain that this was ever done. Attempts were made to slave the pod's optics to the aircraft radar, but these were not successful. The system operated by having the pod look in the same direction as the pilot's bomb sight, with the weapons system officer then finding the target on his monitor screen as the pilot pointed his aircraft at it. Pave Knife aircraft included 66-7652, 7674, 7675, 7679, 7681, 7707, 7709, 7743, 7760, 7766, and 7773. Combat missions with the Pave Knife began on May 23, 1968, initially in conjunction with the GBU-10/B laser-guided bomb. All *Pave Knife* aircraft were assigned to the 433rd TFS of the 8th TFW. Perhaps the most spectacular use of the Pave Knife was the dropping of a span of the Paul Doumer Bridge near Hanoi on May 10, 1972. This bridge had survived literally hundreds of previous attacks.
Two F-4Ds (66-8738 and 66-8812 were fitted with the AVQ-11 Pave Sword precision attack sensor. This consisted of a modified AIM-9 Sidewinder seeker head as a laser spot tracker for targets designated by AVQ-12 Pave Spot laser designators carried by O-2As. The system was mounted inside a modified SUU-11 gunpod that was suspended from the right-forward Sparrow well or from the right inboard underwing pylon.
F-4D number 66-8700 received the Pave Fire system mounted in a centerline pod. This system was supposed to use low-light level television and laser ranging equipment to perform dive-toss bombing missions at night. In such a mission, the attacking aircraft was supposed to dive on the target from a medium altitude, acquire and designate the target, then pull up before releasing its "dumb" bombs. However, the designation of the target was found to be more tricky than expected, and the Pave Fire system was never very successful, and only one Phantom was so modified.
The AVQ-9 Pave Light laser designator was fitted to 65-0597, 0609, 0612, 0642, 0677, 0706, 0786, and 66-8814, 8815, 8817, and 8823. This designator was mounted on the left side of the rear canopy frame of the F-4D. In order to use the system, the pilot had to fly in a left turn around the target and shine the laser while other aircraft attacked it. If an emergency escape proved to be necessary, the WSO first had to demount and store the designator before he could safely eject. Aircraft fitted with the Pave Light system were assigned to the 8th TFW.
AN/ARN-92 LORAN-D equipment was fitted to Pave Phantom F-4Ds. They could be identified by a rather prominent "towel-rail" antenna on the upper rear fuselage behind the rear cockpit. A total of 72 aircraft from blocks 32 and 33 were so equipped. In Vietnam, the primary mission of these Pave Phantom F-4Ds was the seeding of the Ho Chi Minh trail with sensors, which required the precise nighttime navigational capability provided by LORAN. The primary operators of the "towel-rail" F-4Ds were the 25th and 497th TFS of the 8th TFW and the 555th TFS of the 432nd TFW. Subsequently, these planes were passed along to the 457th TFS of the 301st TFW, the 23rd TFS of the 52nd TFW, and the 704th TFS of the 924th TFG.
The Combat Tree modification of 1968-69 permitted the retention of a full missile load while carrying electronic countermeasures gear. It did this by adding an attachment point for a countermeasures pod on the inboard pylon, which could now carry two more AIM-9J Sidewinder missiles on each side.
Under the Pave Arrow program, two F-4Ds were equipped with a Sidewinder infrared seeker mounted in a fixed pod for locating heat sources from ground targets.
The designation EF-4D was given to four F-4Ds modified for the Wild Weasel IV/V SAM suppression role. 65-0657 and 65-0660 were fitted with the AN/APS-107 radar homing and warning system and a target acquisition system for AGM-78 Standard anti-radiation missiles. 66-7635 and 66-7647 served as test beds for the AN/APS-38 warning and attack system developed by McDonnell Douglas and later adopted for the F-4G.
The F-4D served with the following Air Force Tactical Fighter Wings: 3rd, 4th, 8th, 12th, 18th, 33rd, 35th, 36th, 48th, 49th, 50th, 52nd, 56th, 57th, 81st, 354th, 366th, 388th, 401st, 405th, 432nd, 474th, 475th and 479th.
As part of the Shah's ambition to turn Iran into a major world power, the Nirou Havai Shahanshahiye Iran (Imperial Iranian Air Force) placed a order for 16 F-4Ds in 1967. A second batch of 16 more F-4Ds was later ordered. The first F-4Ds arrived in Iran on September 8, 1968, with a total of 32 F-4Ds being ultimately delivered to the Imperial Iranian Air Force. They were later supplemented by large batches of F-4Es and RF-4Es, which made Iran the third-largest operator of the Phantom after the USA and Israel. Iranian F-4Ds were used in unsuccessful attempts to intercept Soviet MiG-25s that were spying on Iran. Their first combat use was in 1975 when Iran provided assistance to the Sultan of Oman in action against rebels. One of these was lost to ground fire. With the overthrow of the Shah in 1979 by the Islamic fundamentalist revolution, the shipment of spare parts for Iranian Phantoms was embargoed, and many planes had to be cannibalized to keep others flying. However, some spare parts have managed to sneak into Iran from Israel and from some NATO countries. When Iraq attacked Iran in September of 1980, only 40 percent of the Iranian Phantom force was operational due to a shortage of replacement parts.
In 1968, the Republic of Korea, having gotten rather nervous about border clashes with North Korea, ordered an initial batch of 18 F-4Ds. This order was filled using aircraft drawn from from existing USAF stocks rather than by new construction. The first four F-4Ds arrived in Korea in August of 1969. Eventually, at least 42 ex-USAF F-4Ds were transferred to South Korea, the last being delivered in 1988.
In the early 1980s, F-4Ds began to reach Air Force Reserve units. The units
obtaining the F-4D included:
By the late 1980s, most of the AF Reserve units had exchanged their F-4Ds for F-16A/Bs. The last AF Reserve unit to use the F-4D, the 482nd TFW, converted to F-16A/Bs in November of 1989.
In the late 1970s and early 1980s, ex-USAF F-4Ds began to reach the Air
National Guard. The first ANG unit to operate the F-4D was the 178th FIS of the
119th FIG of the North Dakota ANG, which got its planes in March of 1977. ANG
F-4Ds served both in the tactical fighter role and in the interceptor role. The
following ANG units are known to have operated the F-4D:
During the early 1990s, the F-4Ds in the ANG were all withdrawn from service and have been replaced by F-16s. By 1992, the last F-4Ds had been withdrawn from the fighter interceptor groups of the Air National Guard.
No F-4Ds remain in service with any unit of the USAF or the Air National Guard. However, numerous F-4Ds remain flying with the Republic of Korea Air Force. It is uncertain how many F-4Ds remain in service in Iran, but probably most are by now grounded due to the lack of spare parts and are no longer serviceable.
64-0929/0937 McDonnell F-4D-24-MC Phantom 64-0938/0963 McDonnell F-4D-25-MC Phantom 64-0964/0980 McDonnell F-4D-25-MC Phantom 65-0580/0611 McDonnell F-4D-26-MC Phantom 65-0612/0665 McDonnell F-4D-27-MC Phantom 65-0666/0770 McDonnell F-4D-28-MC Phantom 65-0771/0801 McDonnell F-4D-29-MC Phantom 66-0226/0283 McDonnell F-4D-29-MC Phantom 66-7455/7504 McDonnell F-4D-29-MC Phantom 66-7505/7650 McDonnell F-4D-30-MC Phantom 66-7651/7774 McDonnell F-4D-31-MC Phantom 66-8685/8698 McDonnell F-4D-31-MC Phantom 66-8699/8786 McDonnell F-4D-32-MC Phantom 66-8787/8825 McDonnell F-4D-33-MC Phantom 67-14869/14876 McDonnell F-4D-35-MC Phantom (for Iranian AF) 67-14877/14884 McDonnell F-4D-36-MC Phantom (for Iranian AF) 68-6904/6911 McDonnell F-4D-37-MC Phantom (for Iranian AF) 68-6912/6919 McDonnell F-4D-38-MC Phantom (for Iranian AF)
Engines: Two General Electric J79-GE-15 turbojets, 10,300 lb.s.t dry, 17,000 lb.s.t. with afterburner. Performance: Maximum speed 1432 mph at 42,000 feet (Mach 2.17), 826 mph at sea level (Mach 1.08). Cruising speed 587 mph. Landing speed 165 mph. Inital climb rate 40,100 feet per minute. Service ceiling 55,850 feet. Combat range 502 miles, maximum range 1844 miles with maximum external fuel. Weights: 28,958 pounds empty, 51,577 pounds gross, 38,781 pounds combat weight, 59,380 pounds maximum takeoff weight. Dimensions: Wingspan 38 feet 5 inches, wing area 530 square feet, length 58 feet 3 3/4 inches, height 16 feet 3 inches. Fuel; Maximum internal fuel in the fuselage tanks was 1260 gallons. An additional 630 gallons of fuel could be carried in internal tanks inside the wings. Maximum external fuel load was 600 US gallons in a centerline tank that could be carried underneath the fuselage plus 370 US gallons in each of two tanks that could be carried underneath the outer underwing pylons, bringing total fuel load to 3230 US gallons. Armament: Armament consisted of four AIM-7 Sparrow semi-active radar homing air-to-air missiles in semi-recessed slots in the fuselage belly, plus two to four AIM-9 Sidewinder infra-red homing air-to-air missiles carried under the wings on the inboard pylons. A total offensive load of up to 16,000 pounds could be carried on the centerline and four underwing hardpoints.