AMC1 31TGB.22 In-Service load cases

• ED Decision 2013/011/R found in: CS-31TGB Initial issue - Tethered Gas Balloons (Jul 2013)

AMC1 31TGB.22 In-Service load cases ED Decision 2013/011/R Inflation/mooring The ‘inflation and mooring cases’ referred to in this requirement cover assembly, disassembly, inflation, deflation and mooring load cases. Mooring load cases cover both low and high mooring, if applicable. When the balloon is moored in the parking position (low mooring) the maximum gas pressure in the envelope is normally identical to the ‘maximum gas pressure’ established for any of the flight conditions. If the low mooring operation, however, allows for a precautionary increased pressure of the gas in the envelope this load case is also considered. Flight Flight load cases cover the operation within the established limitations (temperature, wind speed, mass, and ascent/descent speed limitations). A dynamic lift component is considered in the load cases for the sudden deceleration of the ascent/descent unit and when the envelope shape is not spherical and generates lift in wind conditions. When a dynamic lift component is applicable, gust loads are considered as well as potential oscillation behaviour of the balloon and the tether caused by airflow and from variations in the lift component and its centre of pressure.