My view is that if you really expect your plane to burst into flames at any time, you should stay on the ground.
Wearing fireproof clothing will do you sod-all good when the cockpit fills with fumes, which will prob99 happen long before you get any flames. Are you going to wear a hood with an air bottle on the back of it as well?
Planes don't just catch fire in the air on a routine basis. On the extremely rare occassions they do that, it is normally the result of shameful maintenance practices (assisted by the equally shameful European regulatory regime which for the most part sells job creation under a "safety" wrapper), and occassionally (on non-CofA planes) the result of stupid design.