Originally Posted by
bigoil
Can someone please give me a technical reason for the hollow bolt design?
Like in the wing bolts of some ac and apparently helicopter blade bolts.
Thanks
In most cases stress loads on a object such as a bolt are taken up by its surface(s) not the core of the bolt.
Another reason is to save weight and in the case of blade bolts they are used to store additional weight for main rotor balancing purposes.