AD Note Issued for GV and GV-SP

A new Gulfstream GV and GV-SP airworthiness directive calls for an inspection to determine whether a third Halon fire extinguisher bottle is installed in the APU fragment impact zone, revising the limitations section of the airplane flight manual to add restrictions for APU usage for certain airplanes having a third fire extinguisher bottle, and removing the third fire extinguisher bottle from certain airplanes. The intent is to prevent penetration of the bottle by fragments released due to APU rotor system failure, which could cause substantial damage to the primary airframe structure and primary flight controls.