I saw a 16000 topal over cause the operator boomed down to far without setting the block down or grabbing it with the lull to carry it. Boom down it went. No one got injured.
My guess it try to get some of the main stress from raising the boom from ground level to something more reasonable so the drums do not have as much stress on them
That is a good question. I am surprised nobody has given you an answer. I would like to know myself. I am no engineer, but from looking, It appears the cables from the mast to the end of the boom, when it is completely down, are very close to being parallel to the boom its self. I think that would put too much stress on the cables and the boom.
