Let’s move POD to 1967 after the Israeli Air Force bombed Arab air forces back into the Stone Age and everyone learned that long runways were vulnerable.
Let’s also move away from the “large Air Force” mentality by specifying a small nation with considerable industry ..... say Switzerland or Sweden. ..... or maybe funding from a filthy-rich country with little industry ..... say an oil producing nation like Brunei.
Then define mission: interceptor or ground-attack.
You have to keep it light because gross weight defines engine thrust, price, runway length, etc. 20,000 pound gross weight is a convenient point to start discussion. 20,000 pounds was also available from a variety of 1969s vintage, low by-pass jet engines.
Short take-offs are easy with huge thrust reserves. Just keep gross weight at 80 percent of engine thrust. Even better if your engine can develop that thrust without afterburners.
If your short take-off depends primarily to huge amounts of engine thrust, you can get by with a comparitively small wing .... meaning a heavy wing-loading with multiple bombs hanging off multiple wing pylons.
Next question is whether you will need puffer ports for control at low air speeds?????
Short landings get easier the lighter the gross weight.
First generation STOL fighters would only be able to land short near empty weight. That means expending all under-wing stores and burning most of the fuel.
Since we are already planning heavy fuel or bomb loads, we might as well plan for internal carriage from the start.
Yes, external hard points will still be needed for “weapons not invented yet” but they will not be used initially.
The primary determinant of landing roll is approach speed. The slower the approach speed, the shorter the landing role.
Sure, large wings help reduce stall speeds ...... but what if we stick with medium-sized wings by add massive blown flaps?
If this fantasy fighter can fly final approach behind-the-power-curve, it will deliver little residual energy to the runway threashold. Mind you, losing the engine at low altitude requires instant ejection because there is zero margin for error.
Short landings also assume touching down at high rates of descent. This requires stout landing gear little different than needed for arrested landings on carrier decks.
Simplest to start with LG strong enough for arrested landings.
The primary reason USMC insists upon fielding their own GA aircraft is lack of confidence naval aircraft support. This brings us back to the “small Air Force” concept.
This is similar to our fantasy Air Force that can only afford one or two types of jet combat aircraft. They need a naval variant capable of flying from container ships (ala. Atlantic Conveyor) and an interceptor variant operating from short runways hidden in mountain valleys. Airframe and engine requirements are similar.
Why am I picturing a 20,000 pound, single-seater powered by a high-bypass turbofan. The fan exhausts forward of the centre-of-gravity - maybe into massive blown flaps. That exhaust probably needs shoulder-mounted wings.
Engine core exhaust goes straight out a short tailpipe (as short as F-35 or Yak 141). Maybe the core has an after-burner.
Then we get into a rousing debate about whether to install puffer ports for control at low air speeds.
If fan exhausts were mounted wide enough apart, could they provide roll control?
Could a core exhaust - with a 2d vectoring nozzle - provide sufficient pitch control?