Back to the thread, having read the report there is mention of a standard for the threads protuding through the nut but no mention of standard torque figures.If no torque specified then use standard practises. As per report this had been overtightened so that new threads were cut in the bolt. No mention of how much effort would have been required to achieve this which i think would be relevant. Not just a problem for the RAF , but in my experience basic handskills has suffered in the last few years with the reduction in proper hand skills training in the whole industry. Basic engineering also teaches that a shackle bolt doesnt need to be tight, just secure as it operates in shear. Just such a shame that a simple error like this cost a life, most errors like this never cause a problem