As good as the F-90 looked, even with the J-79s, it would have to lose the tip tanks to dogfight.
But, that's just my thought on it. Perhaps it magically had less roll inertia than it appears from the pics. Another thought would be to use fuel from the wing tanks and automatically pump fuel from the tip tanks to the wing tanks as it is used. That way, the tip tanks would get lighter quickly and maybe not be a factor at all.
Also, Lockheed developed the first American axial-flow turbojet, the company designation was the L-1000 and the military designation was the J-37. The Planes of Fame Museum has one on display. The design called for a weight of 1,700 pounds and a thrust of 5,100 pounds. Final weight was 1,610 pounds. The Army was seemingly uninterested and Lockheed ceased further development. Pic below of the engine at Planes of Fame.
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