BRITISH STANDARD HC
British Standard HC relates to high strength casting materials and products.
British Standards originated in 1901 as an effort to standardise steel sections and later screw threads used in manufacturing, up until 1931 being called the British Engineering Standards Association, or BESA. After this time it was renamed the British Standards Institute and continues to operate to this day as BSI Group. After WW1, an effort was made to specify many of the new aircraft materials developed during the conflict as a body of Aircraft Material Standards. These introduced groupings of materials recognized by a suffix such as ‘S’ for steel, ‘L’ for light metals such as aluminium and magnesium, ‘T’ for tubes and ‘V’ for timbers. Modern versions of some of these Standards continue today and can be secured from the BSI Group.
A number of Indexes are provided to indicate what Standards were current at a specific time and what Standards were revised or canceled at that date.
BRITISH STANDARD CANCELLATIONS AND SUBSTITUTIONS
Where British Standards are revised, the later version will contain a sequential number at the beginning of the title, eg S28, 2S28, 3S28
These Standards were often designed to be disposed off when obsolete, so early revisions are often difficult to find. An earlier version of a Standard does much to explain the material design constraints and possibilities of the day, so the automatic application of a later revision to an earlier design may not be appropriate. An example may be in the use of a modern aluminium sheet with mechanical properties superior to a vintage sheet material, but the higher strength may make the complex forming of a vintage shape, that relied on lower mechanical properties, impossible. Accordingly, multiple revisions and their dates of publication are listed.
Where you have copies of any old aircraft Standards please use the Contact button to arrange scanning and sharing.