CS 31TGB.25 Factors of safety

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

CS 31TGB.25 Factors of safety ED Decision 2013/011/R (a) A factor of safety is used in the balloon system design as provided in the table. <table border="1" cellpadding="0" cellspacing="0" width="569"><tr><td valign="top" width="114"><p><b>Safety factor</b></p></td></tr><tr><td valign="top" width="455"><p><b>Envelope</b></p></td><td valign="top" width="114"><p>5·00</p></td></tr><tr><td valign="top" width="455"><p><b>Suspension and tethering components (fibrous or non-metallic)</b></p></td><td valign="top" width="114"><p>3·50</p></td></tr><tr><td valign="top" width="455"><p><b>Suspension and tethering components (metallic)</b></p></td><td valign="top" width="114"><p>2·50</p></td></tr><tr><td valign="top" width="455"><p><b>Other (This includes mooring components not used for suspension or tethering)</b></p></td><td valign="top" width="114"><p>1·50</p></td></tr></table> (b) Regardless of the materials used, the load-bearing components of the suspension and tethering system is designed so that failure of any single component will not jeopardise safety of flight, and that total failure is extremely remote. Account is taken of any reasonably foreseeable dynamic or asymmetric loading affects associated with the initial element's failure. (c) Where no provision is made for duplication in the suspension or tether system, the factor of safety is to be multiplied by a factor of 1·5. (d) For design purposes, an occupant mass of at least 77 kg is assumed.