I’m not going to tell you what to do. I am going to point out the red flags you cited and ask what you would say to a friend who was considering dating someone who behaves like this.

he kept talking about… that i should’ve ditched my bf for him

In other words, he did not respect your relationship when you were in one.

badmouthed not only his gf of a few years

He handles struggles in a relationship by badmouthing his partner to others,

he left her bc she showed signs of schizophrenia

and uses an armchair diagnosis as an excuse to get out of a relationship instead of just saying it’s not working for him anymore like an adult.

he kept guilttripping me when i said i didn’t want to be his gf

He doesn’t care about your preferences, and tries to manipulate you when they don’t match his.

The basic way an airplane works actually is simple and intuitive: it meets the air at an angle and deflects it downward. The equal and opposite reaction to accelerating that mass of air is an upward force on the wing.

There is, of course a whole lot of finesse on top of that with differences in wing design having huge impacts on the performance and handling of aircraft due to various aerodynamic phenomena which are anything but simple or intuitive. A thin, flat wing will fly though, and balsa wood toy airplanes usually use exactly that.

https://en.wikipedia.org/wiki/Lift_(force)#Simplified_physical_explanations_of_lift_on_an_airfoil

If I remember right, he would have been eligible for a life sentence for the original charges.

I knew someone who raped both his daughters.

He was prosecuted and took a plea deal, probably offered to spare them a trial. I think he did about ten years in prison, which I would argue is less punishment than he deserved.