I've been working on a system for ships to do something similar to the disintegrating plane thing I mentioned earlier. I wrote a fairly detailed description on how it works, and I touched on part disconnection mechanic and such. Might have some info you find useful for this project
https://www.simpleplanes.com/a/9K7E8p/Sinkable-ship-damage-model-buoyancy-Description-Redone

Also some explanation on cannon
https://www.simpleplanes.com/Forums/View/1496330/SIMPLECHEATS-II-an-updated-comprehensive-list-of-all-known-XML-attributes#comment-4227148

@McChezborger

Collab

Not sure if I can do like a collab build, but I would love to discuss ideas or maybe make/provide some components. If that's good enough
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Parts don't break when disconnected

As for parts disconnection, I guess it's kind of possible? Generally not with weapons that make explosion though (due to "insta-kill switch" mechanic of explosion damage)
You can set their HP really high and/or disable their collision, and set partCollisionResponse to None. Setting pCR to None will take a part either no or less damage from ground collision, and somewhat reduces the chance of entire plane exploding in chain-reaction (if the damage source is non-explosive or small enough explosion)/if you are building an armored vehicle (ship or tank), you basically want to set it to None for pretty much every part in the build.
How you connect parts will also play a large role in the way a plane breaks.

@Kendog84 could we possibly collab? I have ideas

@Kendog84 is there any way I could make it to where the part doesn’t get destroyed when it disconnects?

Sounds good! @Kendog84

@McChezborger
That sounds really cool, I'd be excited to see it done!
Throwing some ideas at you, I think cannon might work better than wing-gun/gatling gun (cannon rounds go through blocks with collision disabled). (Ignore this if you've already thought of it)

AI uses (forced to use) AirToAir/multirole cannon if they fire at least one AA missile and run out of missiles, so it might even be possible to get your 'brain' shot by enemy without losing your entire plane.

Regardless, that sounds really inventive and cool, I'd say you should go for it.
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If you don't mind going some extra miles, you can probably make your plane disintegrate a bit more realistically (given that AI enemy is using cannon rather than wing gun) by disabling the collision of major exterior parts like wings and fuselage blocks, connecting them with blocks that have collision (partCollisionResponse of exterior parts must be set to None). This way, when cannon rounds destroy the connectors, plane will fall apart instead of exploding. Hit box can be matched with how the plane looks, simply by shaping & sizing these connectors like the exterior. Hm... I might make a demo plane for the disintegration system later, I was just playing with the idea in my head but this seems pretty neat. If combined with your pilot mechanism, it might make some pretty fun planes to shoot at

@Kendog84 I’m thinking of making a mechanism where there’s a block in the head (the head has no collisions) which simulates the “brain” which is the only connection the cockpit has, so if that gets destroyed, you lose control because the pilots “dead”. The brain will also be connected to a piece in the chest, which will connect the “brain” to the rest of the plane, which will simulate the “heart”

Thanks for the mention, they look very nice!
Love the long jacket (coat?)