NEW DELHI: Investigating the uncommanded deployment of the ram air turbine (RAT) – a procedure triggered during engine failures – on an Air India Boeing 787 flight on October 4, Directorate General of Civil Aviation (DGCA) has directed the airline to reinspect RATs on all aircraft where the power conditioning module (PCM) was recently replaced.The directive aims to determine whether there is any correlation between the newly replaced PCM and the uncommanded RAT deployment. DGCA has also asked the US aerospace major to submit a “comprehensive report outlining the preventive measures to be implemented” to address such uncommanded RAT deployments.On Oct 4, an Air India B787-8 (VT-ANO) experienced an uncommanded RAT deployment while approaching Birmingham, UK. “During landing, at about 400 feet, a RAT unlock message appeared and RAT deployed. The pilot did not report any associated abnormality,” an official said.