self locking bolts

designed for shock load

used in aircraft application

provided with hexagonal depression in head

initial tension

external load applied

relative elastic yielding (springness) of the bolt and the connected member

All of the above

is just sufficient to hold parts together

approaches yield point

is 50% of yield point

is about yield point divided by safety factor

joint may not open up

bolts are weakest elements

the resultant load on the bolt would not be affected by the external cyclic load

bolts will not loosen during service

square

acme

buttress

BSW