Summary
This document proposes to adopt a new airworthiness directive (AD) that would apply to certain SOCATA--Groupe AEROSPATIALE (Socata) Model TB 21 airplanes. This proposed AD would require you to modify the exhaust system. This proposed AD is the result of mandatory continuing airworthiness information (MCAI) issued by the airworthiness authority for France. The actions specified by this proposed AD are intended to prevent high levels of carbon monoxide from entering the cockpit during certain flight configurations, which could result in the pilot becoming incapacitated or impairing his/her judgement. Such a condition could lead to the pilot not being able to make critical flight safety decisions and result in loss of control of the airplane.