BS 2M 47:1990 pdf free.Specification for Retreading of cross plytyres for aircraft.
BS 2M 47 Minor injuries to the bead areashall be repaired provided the plies are not
damaged.Bead seal.The bead seal shall not be affectedor intersected by impressions or depressions. Bead face and bead heel.The bead face andbead heel areas shall be smooth.
Bead toe.The bead toe shall be trimmed sothat no edges are exposed above the bead face and sothat any bead toe flash remaining does not protrudemore than 3 mm from the face contour of the bead.If trimming of the bead toe is necessary, the trimming shall not cut or expose the tyre cord material or more than one layer of chafer material.3.3.8 Chafer strip. Minor injuries in the chafer stripand slight tyre tool injuries in the general bead areashall be repaired if they do not extend into the pliesof the tyre and if there is no sign of separation in thebead area.Loose or blistered chafer strips shall berepaired or replaced.Inner liner. Inner liner surface damage anddefects other than liner splices that are less than 50 mm in length shall be repaired.A maximum of 10 of these repairs shall be acceptablewith no more than three repairs in any quadrant.Liner splice damage defects shall be repaired if lessthan 250 mm in length.
Exposed cord. Exposed cord, either in thebreaker or carcass ply, shall not exceed 1 % of thebuffed total tread area on one spot or more than 2 %for the entire tyre.Exposed cord shall not exceed onecarcass ply in depth.
Type testing shall be conducted on firstlife (R1) retreaded tyres manufactured from
carcasses that have been previously approved bythe approving authority (see foreword) for eachaircraft type to which it is intended to fit theretread.Carcasses used to manufacture R1 retreads fortype testing shall have been worn to a minimumof 80 % in service, and shall have representativemaximum damage repairs (see 3.3 or 3.4) naturallyor artificially induced.BS 2M 47 pdf download.