I never fly without my aluminium foil pyramid on my head. Not only does it protect me from radiation, but it increases my mental capacity!
I used to wear a full body lead-suit to prevent the rays hitting me, but my C-150 couldn't get airborne anymore!
Probably more likely to die in a plane-crash than from radiation poisoning - and the likelihood of dying in a plane-crash (of your own devices or not) is extremely low. Probably more likely to die from the rays of the sun, than radiation, in real life.