Designation:F320−10StandardTestMethodforHailImpactResistanceofAerospaceTransparentEnclosures1ThisstandardisissuedunderthefixeddesignationF320;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(´)indicatesaneditorialchangesincethelastrevisionorreapproval.ThisstandardhasbeenapprovedforusebyagenciesoftheU.S.DepartmentofDefense.1.Scope1.1Thistestmethodcoversthedeterminationoftheimpactresistanceofanaerospacetransparentenclosure,hereinaftercalledwindshield,duringhailstormconditionsusingsimulatedhailstonesconsistingoficeballsmoldedundertightlycon-trolledconditions.1.2Thevaluesstatedininch-poundunitsaretoberegardedasstandard.ThevaluesgiveninparenthesesaremathematicalconversionstoSIunitsthatareprovidedforinformationonlyandarenotconsideredstandard.1.3Thisstandarddoesnotpurporttoaddressallofthesafetyconcerns,ifany,associatedwithitsuse.Itistheresponsibilityoftheuserofthisstandardtoestablishappro-priatesafetyandhealthpracticesanddeterminetheapplica-bilityofregulatorylimitationspriortouse.ForspecifichazardstatementsseeSection7.2.Terminology2.1Definitions:2.1.1damage—anymodificationinvisualpropertiesorintegrityofawindshieldasaresultofhailimpactincludingscratches,crazing,delamination,cracks,orshattering.2.1.2iceball—afrozenmassofwater,withfiller,thatsimulatesanaturalhailstoneinweight,size,andtoughness.2.1.3impactangle—theanglebetweentheiceballflightpathandthetargetnormal.2.1.4sabot—aplasticdeviceforprotectingtheiceballwhileinthelaunchtube.Onetypeofsabot(seeFig.1)consistsofasplitpolycarbonaterodcontainingacentralcavityforholdingtheiceball.Eachsabothalfisdesignedtoassureaerodynamicseparationfromtheiceballafterejectionfromthelaunchtube.3.SummaryofTestMethod3.1Thetestmethodinvolveslaunchingaseriesoficeballsofspecifiedsizesatasamplewindshieldatadesignatedvelocityandangleandinaspecifiedpattern.Requirementsarespecifiedfortheiceball,testsp...
