and showing at least one and a half threads
Standard securing in case you do not know to ensure a nut and bolt are in Safety.
For your Info,The US have a different take on the amount required to be showing though, it being less.
It's been so long since I touched a Military Jet, but the Civilian side of things, if a torque is not specifically mentioned, there is normally a chart in the front of the manual with generic torque settings for standard nuts and bolts, however, one suspects the shackle bolt was not a standard item.