ASTM_F_2355_-_14.pdf

Designation:F235514Standard Specification forDesign and Performance Requirements for Lighter-Than-AirLight Sport Aircraft1This standard is issued under the fixed designation F2355;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year of last revision.A number in parentheses indicates the year of last reapproval.Asuperscript epsilon()indicates an editorial change since the last revision or reapproval.1.Scope1.1 This specification covers design and performance re-quirements that apply for the manufacture of lighter-than-airlight sport aircraft.1.2 This standard does not purport to address all of thesafety concerns,if any,associated with its use.It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory requirements prior to use.2.Referenced Documents2.1 ASTM Standards:2F2354 Specification for ContinuedAirworthiness System forLighter-Than-Air Light Sport AircraftF2356 Specification for Production Acceptance Testing Sys-tem for Lighter-Than-Air Light Sport AircraftF2427 Specification for Required Product Information to beProvided with Lighter-Than-Air Light Sport AircraftF2483 Practice for Maintenance and the Development ofMaintenance Manuals for Light Sport AircraftF2563 Practice for Kit Assembly Instructions of AircraftIntended Primarily for RecreationF2972 Specification for Light Sport Aircraft ManufacturersQuality Assurance System3.Terminology3.1 Definitions:3.1.1 airshipengine-driven lighter-than-air aircraft thatcan be steered.3.1.1.1 DiscussionThis definition can include“and thatsustains flight through the use of either gas buoyancy or anairborne heater,or both.”3.1.2 balloonlighter-than-air aircraft that is not engine-driven,and that sustains flight through the use of either gasbuoyancy or an airborne heater,or both.3.1.3 design useful loadload(other than structure,engine,enclosure,and systems)that a lighter-than-air aircraft can carrywhile achieving the design defining performance requirements.3.1.4 gross weighttotal aircraft system weight(s)at take-off.3.1.5 lighter-than-air aircraftaircraft that can rise andremain suspended by using contained gas weighing less thanthe air that is displaced by the gas.3.1.5.1 DiscussionAirships may include dynamic lift thatderive as much as 30%lift from other than buoyancy.3.1.6 maximum takeoff weightgross weight limit as de-fined by the manufacturer,proven through compliance withthis specification and placarded on the aircraft as the not-to-exceed gross weight.3.1.7 thermal airshipairship using heated air for a portionof its lift,incorporating design features to prevent nosecollapse due to dynamic pressure and exempt from specificpressurized envelope requirements.3.1.8 vectored thrust balloonthermal balloon with thrustcapability that does not have design features to prevent forwardenvelope collapse due to dynamic pressure and is thereforelimited in its lateral speed capability.3.1.9 weight limitationsoperational weight restrictions(maximum/minimum)as defined by the manufacturer andproven through compliance with this specification to demon-strate controllability.4.Flight Requirements4.1 Performance Requirements for Airships and ThermalAirships,except as noted:4.1.1 Proof of ComplianceEach of the following require-ments shall be met at the maximum takeoff weight and mostcritical center of gravity(CG)position.To the extent that CGadjustment devices may be adjusted for flight,these compo-nents will be evaluated in the least favorable recommendedposition as it affects either performance or structural strength.4.1.2 General PerformanceAll performance requirementsapply in and shall be corrected to International Civil Aviation1This specification is under the jurisdiction of ASTM Committee F37 on LightSport Aircraft and is the direct responsibility of Subcommittee F37.60 on Lighterthan Air.Current edition approved Nov.1,2014.Published November 2014.Originallyapproved in 2005.Last previous edition approved in 2013 as F2355 13.DOI:10.1520/F2355-14.2For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.For Annual Book of ASTMStandards volume information,refer to the standards Document Summary page onthe ASTM website.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 Organization(ICAO)defined standard atmosphere in still airconditions at sea level.Speeds shall be given in indicated(IAS)and calibrated(CAS)airspeeds in knots.4.1.3 Flight PerformanceFor all flight operations it shallbe shown that control sufficient to safely maneuver or land theairship,or both,can be maintained.4.1.4 ClimbThe following shall be measured:4.1.4.1 Distance to clear a 15-m(50-ft)obstacle not toexceed 213 m(700 ft)from point of lift-off.Compliance withthe requirements of this section must be shown at each extremeof altitud