Originally Posted by
Wales-Bales
Not all light aircraft have de-icing systems fitted, which may suggest that they are optional. One of the ways to defeat icing conditions is to climb to a higher altitude of around 25,000ft into commercial airspace, but the pilot didn't have the correct rating to take that course of action, hence he requested a decent to a lower altitude. However, the cause and timing of the carbon monoxide exposure is still unknown (to us), so all possible avoidance strategies may have been futile. It sounds like a case of whatever could go wrong, did go wrong on this flight.