I went to Florida Jets in 2010, and flew my new F-15. The 1st, and only flight went great, until I flew downwind and got ready to turn 90 degrees, then it disappeared. The sky was blue with a little haze, the F-15 was white, and it was gone. I frantically searched the sky, no plane, it finally came into view about 20 ft off the ground, it was level, and it pancaked flat. End of the F-15. A trip the ophtalmologist revealed a caract in the right eye, that partially covered the lense, which the doc. said would cause a prisim effect, bouncing light around the eye, and causing a whiteout. It happens intermittent from different angles. Or , when you happen to be flying a beautiful, F-15. They ( the insurance co. standards ) said it was not enough to warrant a lense inplant, your vision must be 20/40, nevermind the prisim effect thing. So, I didn't fly jets that summer, and returned a year later when I "quallified" for the insurance to cover it.( apparently, insurance people don't fly jets ) The procedure is nothing and it goes like this. Lay on a gurney, chat with nice nurses, they put a thing in your arm, you relax, but you can remember. They wheel you in to a room, doc. comes in, says hi, starts doing "something" with your eye, I remember a bright light moving around, then he says all done. They put a plastic patch over the eye, you go home. Never felt a thing. Next day, you go to his office, he removes the plastic patch, checks it out, home you go. You wear the patch when you sleep for a couple days, and put drops in two or three times a day until they are gone.
I never felt a thing, I still need glasses . A little " fogging" developed on the lense, barely noticed it, but I did notice. They said it happens sometimes, come back in a year, and we will lazer it clear in a minute, ( in office ) So, I fly again, and have an " implant ", that I can talk about. It is fantastic technology. I hope this helps qualm your fears.
Dale