By 1970, the Navy was beginning to be concerned about the condition of its fleet of F-4Bs, many of which were over ten years old and showing signs of old age and fatigue. In that year, a program named Bee Line was initiated in which F-4Bs were refurbished and modernized. Ultimately, 228 Navy F-4Bs went through the Bee Line program. These refurbished planes were redesignated F-4N.
Aircraft selected for conversion were sent to NAS North Island, California, where they were stripped and inspected. They were then completely rebuilt using new parts. The changes included a structural strengthening to extend the fatigue life, plus a complete rewiring. The electrical generating system was upgraded with 30-kVA constant speed alternators. The F-4N retained the thin wings and tires, the main radar, and the undernose infrared search and track detector of the F-4B.
The F-4N was fitted with an F-4J-style slotted stabilator which helped solve “Mach tuck” problems when decelerating from supersonic speeds and which reduced approach speeds during landings. All F-4Ns had their inboard leading-edge flaps locked shut.
The F-4N was fitted with Sanders AN/ALQ-126 or -126B deceptive electronic countermeasures equipment. This included long antenna fairings mounted on the sides of the upper air intakes. These long fairings were the distinctive features which enabled F-4Ns to be externally distinguished from F-4Bs. The DECM antennae were in longer fairings than those used by the same equipment on the F-4J because of the difficulty in routing the cables.
Radar homing and warning antennae for the ALQ-126 DECM were fitted to the undersides of the intakes and wings (just aft of the undercarriage bays). These were tied into the antennae on the trailing edge (and sometimes on the leading edge as well) of the vertical fin.
Other changes included a helmet sight Visual Target Acquisition System (VTAS) and a Sidewinder Expanded Acquisition Mode (SEAM). A new dogfight mission computer was provided, together with auto-altitude reporting equipment. APX-76 or APX-80 air-to-air IFF equipment was fitted, plus AN/ASW-25 one-way datalink. The J79-GE-8 engines of the F-4B were retained, although smoke abatement equipment was fitted.
The first F-4N flew on June 4, 1972. he first renovated F-4Ns joined the fleet in February of 1973. The following Navy squadrons flew the F-4N:
Atlantic Fleet:
VF-41, VF-84, VF-171
Pacific Fleet:
VF-21, VF-51, VF-51, VF-111, VF-151, VF-154, VF-161
Navy Reserve:
VF-201, VF-202, VF-301, VF-302
The F-4N also served with several Marine Corps squadrons:
VMFA-112, VMFA-134, VMFA-314, VMFA-321, VMFA-323, VMFA-351, VMFA-531, VMFAT-101.
Navy Fighter Squadrons in the 70’s and 80’s were referred to as “VF”, Marine Corps Fighter Squadrons were named VMF but in recognition of both the Fighter and Attack Role of the Phantom were referred to as VMFA.
The F-4N had a relative short life as an active-duty fighter with Navy carrier-based units, being replaced by the Grumman F-14A Tomcat during the mid- to late 1970s. However, VF-154 flew F-4Ns off the USS Coral Sea until the end of 1983, when they finally traded in their Phantoms for Tomcats. The F-4N soldiered on for a few years longer with Naval and Marine Corps reserve units until being replaced by either the F-4S (a conversion of the F-4J) or by the F/A-18 Hornet during the early 1980s. The last Navy F-4N was retired from VF-201 based at NAS Dallas, Texas in February of 1984. The last Marine Corps unit to fly the F-4N was VFMA-134, which relinquished the type in 1985.
The following F-4Bs were converted to F-4N configuration. They are listed in order of conversion:
153034, 150430, 150652, 150491, 150452, 150635, 150444, 151398, 150460, 151424, 150407, 150634, 150441, 151016, 151451, 150422, 151491, 150996, 151015, 150445, 150472, 151433, 151442, 151434, 151006, 151400, 150425, 150479, 150640, 150627, 150450, 150485, 150625, 152235, 152267, 150466, 151439, 152241, 151480, 150412, 151004, 152291, 151431, 150630, 152280, 150411, 152230, 150651, 150468, 151513, 151468, 151435, 150648, 150429, 151417, 151476, 151463, 150492, 152278, 151519, 150482, 150475, 151484, 150476, 152277, 150465, 151430, 151469, 150642, 151456, 151436, 152306, 151000, 151444, 151448, 150436, 152259, 152258, 152272, 152253, 151489, 152229, 150419, 152288, 150643, 150438, 151413, 150456, 150448, 150632, 150423, 151406, 152254, 152236, 150415, 150489, 151003, 152294, 152302, 151471, 152991, 152223, 152275, 150442, 151487, 150426, 150638, 152969, 153024, 152967, 152227, 151502, 151498, 151422, 150478, 152237, 512210, 152059, 153047, 151464, 150432, 150481, 153026, 151401, 153045, 153065, 150464, 152977, 151475, 152318, 152281, 153053, 152295, 153039, 153050, 153023, 152975, 153914, 152981, 153017, 152252, 152313, 152323, 151514, 151452, 151477, 150480, 150440, 153001(?), 152982, 151446, 153016, 152293, 150639, 151008, 152243, 153915, 152226, 151510, 152221, 151440, 152222, 152326, 153058, 153012, 152968, 152965, 151504, 153067, 152225, 152310, 152214, 152317, 152970, 153010, 152212, 152250, 150435, 152208, 153056, 152269, 152996, 152282, 151415, 150993, 151465, 152307, 152300, 152283, 152983, 153036, 153057, 152270, 152990, 152298, 152244, 153019, 153027, 152986, 153062, 153030, 153011, 151503, 151461, 152321, 151002, 152290, 152246, 151449, 151455, 152971, 153064, 150490, 152992, 152303, 152279, 150628, 151007, 152217, 151011, 150484, 153006, 151482, 152327, 151511, 152284, 153034.
As they left service, many F-4Ns were modified as remotely-controlled drones under the designation QF-4N. The first QF-4N conversion was performed in 1983. As compared to the original Phantom drone, the QF-4B, the QF-4N was much more maneuverable and was intended to simulate the most agile targets. This increased agility was obtained by removing everything from the aircraft that was not absolutely essential to the target mission. The rear cockpit was stripped to make space for the AN/ASA-32 analog autopilot and flight control system. However, the front cockpit remained, so the QF-4N can be flown in the manned mode if needed. I have serial numbers of 78 F-4Ns which were converted into QF-4N drones, but undoubtedly more have been converted since this list was published.
The following F-4Ns are known to have been converted to QF-4N drone configuration:
150412, 150415, 150419, 150423, 150432, 150456, 150464, 150475, 150489, 150630, 150993, 150475, 150489, 150630, 150993, 151000, 151002, 151004, 151007, 151406, 151415, 151430, 151435, 151440, 151449, 151455, 151461, 151463, 151465, 151469, 151471, 151475, 151476, 151484, 151503, 151504, 152214, 152217, 152221, 152222, 152223, 152226, 152229, 152230, 152235, 152243, 152253, 152258, 152269, 152272, 152277, 152279, 152281, 152282, 152303, 152310, 152321, 152323, 152326, 152968, 152972, 153011, 153024, 153030, 153034, 153034, 153053, 153056, 153058, 153059, 153064, 153065, 153067, 153074, 153076, 153084(?), 153812(?), 153914.
Sources:
-
McDonnell Douglas Aircraft Since 1920: Volume II, Rene J.
Francillon, Naval Institute Press, 1990.
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McDonnell F-4 Phantom: Spirit in the Skies. Airtime Publishing, 1992.
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Modern Air Combat, Bill Gunston and Mike Spick, Crescent, 1983.
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The American Fighter, Enzo Angelucci and Peter Bowers, Orion, 1987.
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United States Military Aircraft Since 1909, Gordon Swanborough and
Peter M. Bowers, Smithsonian, 1989.
- 153001 listed as being shot down in 1967, and on display in museum in Hanoi. Unlikely that it was converted to F-4N.
