Regulation 60

Longitudinal stays shall have a tensile strength between the limits of 28 tons and 35 tons per square inch, with an elongation of not less than 20 or 24% measured on standard test‑piece B or F respectively, but a range of not more than 4 tons per square inch shall be permitted in any one case.

Combustion chamber stays shall have a tensile strength between the limits of 26 tons and 30 tons per square inch, with an elongation of not less than 23 or 28% measured on standard test‑piece B or F respectively.

Angle and tee bars shall have a tensile strength between the limits of 28 tons and 32 tons per square inch, with an elongation of not less than 20% measured on the standard test‑piece A.For material under ⅜ inch in thickness the elongation may be 3% less.

Rivet bars shall have a tensile strength between the limits of 26 tons and 30 tons per square inch of section, with an elongation of not less than 25 or 30% measured on standard test piece B or F respectively. The bars may be tested the full size as rolled.