<h1>Regulator opens formal probe after uncommanded ram air turbine deployment on 787-type during final approach; safe landing reported</h1> A national aviation regulator has opened a formal probe after the ram air turbine (RAT) unexpectedly deployed on a long-haul 787-type aircraft during final approach to landing; the operator reported normal electrical and hydraulic parameters and a safe landing. Manufacturer-recommended maintenance actions for uncommanded RAT deployment were completed with no anomalies and the aircraft returned to service. The investigation will review operational reporting, maintenance logs, compliance with airworthiness directives, potential design or manufacturing defects, and any regulatory or enforcement measures required to address safety, continued airworthiness, and future reporting obligations.