Differences between the Phantom FG.1 and FGR.2

The model F-4M (FGR.2) was an adaptation of the F-4J and F-4K (FG.1) aircraft.  The structure forward of FS 77 is based on the F-4J with the remainder of the aircraft the same as the F-4K (FG.1) with a few exceptions. These exceptions include:

• The F-4K nose gear was replaced with a modified F-4B nose gear.
• All carrier suitability provisions have been removed on the F-4M.
• Local structural changes were made throughout the aircraft for new equipment.
• The vertical tail was similar to the RF-4C. The primary difference between the F-4K and the F-4M was the addition of a leading edge HF antenna in the F-4M vertical tail.

The structural changes would include local beef up for the installation of strike cameras, removal of the pressure activated flooding doors for the foward and aft cockpits, modification of center fuselage bulkheads to provide for cooling air and new wiring harnesses to the enlarged aft equipment bay, and changes to the location of the stabilator feel trim equipment to allow for the enlarged aft equipment bay.

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Top Fin Cap Differences:

Phantom FG.1 (F-4K) Development:

1 - Prototype YF-4K had the standard F-4 fin cap
2 - Production aircraft had the white nav light moved to just above the rudder
3 - Retrofit fairing for the Marconi ARI 18228 Radar Warning Receiver - white nav light moved to the drag chute door.

Phantom FGR.2 (F-4M) Development:

1 - Prototype YF-4M had the standard F-4 fin cap
2 - Production aircraft had the white nav light moved to just above the rudder
3 - Retrofit fairing for the Marconi ARI 18228 Radar Warning Receiver - white nav light moved to the drag chute door.

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Aft Fuselage Differences:

Phantom FG.1 (F-4K) - Left Side

1 - Standard (clean) F-4 drag chute door
2 - See previous section for fin cap differences
3 - Standard F-4J vertical tail
4 - Standard F-4J fuselage panel configuration 

Phantom FGR.2 (F-4M) - Left Side

1 - Drag chute door was modified with nav light after installation of RWR fin cap
2 - See previous section for fin cap differences
3 - The FGR.2 used the same vertical tail as the RF-4C with the large vertical antenna in the forward portion of the tail
4 - The FGR.2 had an enlarged door 61L for enlarged aft equipment bay

Phantom FG.1 (F-4K) - Right Side

1 - Standard (clean) F-4 drag chute door
2 - See previous section for fin cap differences
3 - Standard F-4J vertical tail
4 - Standard F-4J fuselage panel configuration with standard position for door 62

Phantom FGR.2 (F-4M) - Right Side

1 - Drag chute door was modified with nav light after installation of RWR fin cap
2 - See previous section for fin cap differences
3 - The FGR.2 used the same vertical tail as the RF-4s with the large vertical antenna in the forward portion of the tail
4 - The FGR.2 had a new door 61R with a much higher placement and modified shape of door 62 for tail hook servicing

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Revision History:

•  13 MAY 2014 - Original Post

Sources:

• Artwork by Kim Simmelink
• Craig Kaston and his never ending supply of information
• Michael France and his pictures of XV474 at Duxford Museum
• Pictures found on the internet