Special Conditions: Boeing Model 777 Series Airplanes; Seats With Inflatable Lapbelts

These amended special conditions are issued to Boeing Commercial Airplanes for the Model 777 series airplanes. These airplanes have a novel or unusual design feature associated with seats with inflatable lapbelts. Special Conditions No. 25-187-SC were issued on October 3, 2001, addressing this issue. Boeing subsequently applied to amend the special conditions to add a new requirement that addresses the flammability of the material used to construct the inflatable lapbelt. The applicable airworthiness regulations, including those contained in Special Conditions No. 25-187-SC, do not contain adequate or appropriate safety standards for this design feature. The amended special conditions contain the additional safety standards that the Administrator considers necessary to establish an appropriate level of safety considering the safety benefits associated with the inflatable lapbelt.