Thank you for the responses. Another question: I was wondering what the trusses that connect the tension members and compression members do for the boom. Some designs have it but some don't.
They have two purposes:
1. Preventing the boom from "splitting open".
2. Prevent buckling along the compression member
and prevent the whole boomi from collapsing because it's too much pressure downwards for the chords to handle
also to make the boomi firm and prevent it from wobbling side to side
just adds support overall like you dont see real life cranes with no trusses at all