The F-4G was the designation applied to 116 USAF F-4Es which were
converted to the Wild Weasel anti-SAM configuration. These aircraft
should not be confused with the Navy F-4G which was the designation
applied to twelve F-4Bs that were fitted with automatic carrier
landing systems.
Throughout the late 1960s, the Wild Weasel III adaptation
of the F-105F two-seat Thunderchief had been the primary anti-SAM
attack aircraft in Vietnam. However, by 1970 the F-105 airframe was
no longer in production, and attrition in Vietnam had made it a
scarce resource. The need for a replacement for the F-105F Wild
Weasel had become apparent. 36 F-4C airframes had been converted to
the EF-4C Wild Weasel IV configuration, but they suffered from
certain deficiencies which limited their combat effectiveness. For
example, they were unable to carry the Standard ARM. Consequently,
the EF-4C was seen only as an interim Wild Weasel aircraft, pending
the introduction of a more suitable type.
In search of a more lasting solution, the F-4E airframe was selected as a platform for the more advanced Wild Weasel V aircraft. Several EF-4Ds and F-4Es were used in support of the program. F-4E number 69-7254 served as the YF-4G prototype, although it was originally known as the F-4E Advanced Wild Weasel. This F-4G was fitted with leading-edge maneuvering slats. The M61A1 cannon and ammunition drum were removed and replaced by an under-nose fairing that housed forward- and side-looking radar antenna and line replacement units for the AN/APR-38 radar warning and attack system. This system can be reprogrammed at squadron level, and can identify known enemy air-defense radar systems and display their locations in a predetermined order of priority. The under-nose fairing has a ram-inlet that admits cooling air to the interior, which helps to cool the avionics systems inside the nose.
There are a total of 52 receiving and emitting antenna found all over the aircraft. The main receivers are housed in front of the chin gondola that replaced the gun, with others being housed in a pod mounted on top of the fin. Eight of the blade antennas that protrude from the fuselage provide low-band omnidirectional signal reception, with five others being directional and capable of giving the threat bearing on the display in the rear cockpit.
The main radar of the F-4G was the same Westinghouse AN/APQ-120
that was fitted to the F-4E. A new digital processor was added.
Boses for dispensing chaff or flare carteges can be attached to thesides of the underwing pylons. The usual pattern is the Tracor ALE-40, with 30 tubes firing aft.
The backseat crew member has three main displays: a plan-position indicator, a panoramic analysis display, and a homing indicator. The plan-position indicator is duplicated on the pilot's control panel. The plan-position indicator gives the range and bearing of each threat that is identified by the system. The type of each threat is then designated on the display, and the threat deemed by the system to be the most dangerous is identified by having a bright triangle superimposed over it.
In support of its mission, the F-4G could carry the AGM-45 Shrike and the AGM-78 Standard antiradiation missiles.
The Texas Instruments AGM-45 Shrike was the first missile specifically designed for the anti-radiation role. It was based in part on the Sparrow air-to-air missile and had more or less the same configuration. It has a launch weight of about 390 pounds and carries a 145 pound explosive warhead. The range is of the order of 18 to 25 miles. The guidance of the Shrike is provided by a monopulse crystal video receiver. When the receiver in the missile's nose locks onto a target, the crew fires the missile. After launch, the Shrike flies a ballistic path until the control system is activated. At that time, the receiver onboard the Shrike begins updating the guidance by determining the direction of arrival of the hostile radiation, and the missile then homes onto the enemy radar signal with its cruciform center-body wings. The Shrike first became operational in 1965. In Vietnam, the initial experience with the Shrike was rather disappointing. After some trial and error, the enemy found that he could "spoof" the Shrike by simply turning off his radar set, which would cause the Shrike to lose its lock on the target and run out of control. In addition, the receiver of the Shrike was not able to deal with enemy radars that were frequency-agile; all that the enemy had to do to defeat a Shrike attack was to switch his radar to a different frequency. Many versions of the Shrike were produced in an attempt to correct its deficiencies, but none were very successful.
The General Dynamics AGM-78 Standard anti-radiation missile was an attempt to correct some of the deficiencies of the Shrike. It had a longer range and a larger warhead than the Shrike. The AGM-78 was based on the Standard RIM-66A ship-to-air missile. It has a launch weight of about 1400 pounds and carries a 215-pound warhead. Maximum range was about 35 miles. The missile flies on a dual-thrust rocket motor and steers with tail controls and very low-aspect ratio fixed wings. The Standard ARM first appeared in service in 1968. The first version of the Standard had the simple Shrike seeker, but later versions had the Maxson broadband radiation seeker and had memory circuits to deal with radar shutdown tactics.
In addition, the F-4G could
carry the AGM-65 Maverick air-to-ground missile which existed in both
TV-guided and imaging infrared versions. It could also carry the Mk
84 electro-optical glide bomb, the homing bomb system, and cluster
weapons such as the Rockeye, CBU-52, and CBU-58.
In later years, the Texas Instruments AGM-88 High-Speed Anti-Radiation Missile (HARM) superseded most of the former weapons, offering a greatly enhanced kill capability and greater launch versatility. It was designed to provide much higher speeds and much quicker target acquisition times so that radars could be destroyed before they had a chance to be switched off or take other sorts of evasive actions. The HARM has a launch weight af about 800 pounds and has an effective range of about 17 miles. The warhead of the HARM is of a fragmentation variety, which destroys the target by producing a deadly shower of steel cubes. I don't know the weight of the warhead--presumably this is classified information. There are three basic modes of operation for the HARM: Self Protect, Target of Opportunity, and Pre-Briefed. In the Self-Protect mode, the launching aircraft's systems detect the threat and assign its priority. The aircraft's on-board computers then sort the data and pass along to the HARM's computer a set of digital instructions needed to reach the target, and the missile is then launched. The HARM can continue to fly toward the target even if the enemy radar is switched off. In the Target of Opportunity mode, the HARM's sensitive seeker is used to help to determine when to launch against a previously unknown threat. In the Pre-Briefed mode, the HARM can be programmed on the ground for up to three known types of enemy radar emissions. Once in the air, the launching aircraft can fire the HARM blind in the general direction of these known enemy radar emitters. If they are silent, the HARM will self-destruct, but if an enemy site begins to radiate, the HARM will automatically home in on it. Test flights of the HARM began in 1976, and deployment began in early 1983. Earlier versions of the HARM had to be sent back to a depot in the US for reprogramming, but later versions can be reprogrammed on the flight line.
For self-protection, the F-4G could carry up to four AIM-9 Sidewinder air-to-air missiles on the sides of the inboard underwing pylons. In addition, four AIM-7 Sparrows could be carried in the underfuselage slots. However, the left front slot was often taken up by the installation of a ALQ-119 or ALQ-141 jammer pod.
All of the F-4Gs were rebuilds of Block 42 to 45 F-4Es. The first of these aircraft (69-7254) was modified by McDonnell and began flight trials in December of 1975. Subsequent F-4G aircraft were modified by the Air Force at Hill AFB in Utah. The last modification was completed in 1981.
The first F-4Gs went in April of 1978 to the 35th TFW based at George AFB in California. In 1981, the F-4Gs of the 35th TFW were turned over to the 37th TFW, also based at George. In 1989, the 37th TFW was transferred to Tonopah to take over operations of the F-117, and turned their F-4Gs back to the 35th TFW.
In 1979, F-4Gs were issued to the 52nd TFW based at Spangdahlem AFB in Germany. In the same year, F-4Gs were assigned to the 3rd TFW based at Clark AFB in the Philippines.
Following the Iraqi invasion of Kuwait on August 2, 1990, the 561st TFS (part of the 35th TFW based at George AFB) deployed to the Middle East as a part of Desert Shield. Twenty-four F-4Gs were deployed. They were configured with three external fuel tanks (one on the centerline and two underneath the outboard underwing pylons), four chaff/flare dispensors, two AGM-88 HARM missiles on the inboard pylons, and three AIM-7M Sparrow missiles and an ALQ-184 electronic countermeasures pod in the four missile slots.
At the time of Desert Storm, the F-4G was still the only Wild
Weasel aircraft available to the USAF. The F-4Gs of the 35th TFW
played an important part in Operation Desert Storm in 1991, when they
cut a path through Iraqi air defenses during the initial attack on
January 17. The F-4Gs of the 52nd TFW based at Spangdahlem in Germany
were also added to the assets of the 35th TFW based at Sheik Isa AFB
in Bahrain and to the 7440th Composite Wing based at Incirlik AFB in
Turkey. During the war, only one F-4G was lost. It was 69-7571, which
was damaged by enemy AAA on January 18, 1991. It crashed during an
attempted emergency landing, but both crew members ejected safely.
Following Desert Storm and the general defense drawdown after the collapse of the Warsaw Pact, George AFB was scheduled to be closed and the 35th TFW was deactivated. In the summer of 1991, F-4Gs formerly operated by the 35th TFW were turned over to the Idaho ANG, which continues to operate these planes in the present day (1994). Following the closing of Clark AFB in the Philippines, some of the F-4Gs of the 3rd TFW were reassigned to the 7440th Composite Wing based at Incirlik, whereas others were reassigned to the Idaho ANG. Several others have been placed in storage. The 52nd TFW/81st TFS based at Spangdahlem in Germany returned their last F-4Gs to the USA on March 18, 1994. These planes were the last US-operated Phantoms to be based in Europe.
The F-4G is the only version of the Phantom to remain in front-line service with the USAF. It remains in service with the 52nd TFW, but has been transferred from Germany back to the US. The original plan was to replace the F-4G in favor of a Wild Weasel version of the F-16, but this idea was abandoned in 1992. It now appears that the F-4G will be in service until 2000, equipping one Air National Guard squadron, and the 21st TFS of the 52nd TFW. The Idaho ANG squadron had replaced the two squadrons of the 35th TFW at George AFB, which deactivated during 1992.
3rd TFW, 90th TFS
35th TFW
37th TFW (561th TFS, 563rd TFS, 562nd TFTS)
52nd TFW, 81st TFS
4485th Test Squadron
7440th Composite Wing
189th TRTF, 124th TRG, Idaho ANG
190th FS, 124th FG, Idaho ANG
69-0236/0243, 69-0245/0248, 69-0250/0255, 69-0257/0259, 69-0261, 69-0263, 69-0265, 69-0267, 69-0269/0275, 69-0277, 69-0279/0281, 69-0283/0286, 69-0292/0293, 69-0297, 69-0304, 69-0306, 69-7201/7202, 69-7204/7220, 69-7223, 69-7228, 69-7231/7136, 69-7251, 69-7253/7254, 69-7256/7260, 69-7262/7263, 69-7270, 69-7272, 69-7286/7291, 69-7293, 69-7295, 69-7298, 69-7300/7303, 79-7546, 69-7550, 69-7556, 69-7558, 69-7560/7561, 69-7566, 69-7651/7572, 69-7574, 69-7579/7584, and 69-7586/7588.