Also correct in that when the sail is set, the boom will be well clear of the helmsman's head. Even on the Charlotte Rhodes – whose wheel was atop the deck-house – had her boom set high enough that it wouldn't really hit anyone's head if it swung around. (It would indeed have hit the cradle first if it was that low, but the force the boom could carry with it would be enough to smash through the cradle. Oh, the cradle might slow the boom down enough to give a quick-thinking helmsman time to duck, but that's about it.)
If you look closely at the early episodes when Charlotte Rhodes played a large role, you'll notice that all three of her masts have cradles for their booms and gaffs. The ones for the Main and Foremasts are much lower and narrower than the one for the mizzenmast.
I see the new photo of the Soren Larsen crew standing around the wheel. R, you in there?
The photo doesn't show the "roll bar" wooden structure that is behind them in TOL, like in the last episode S8N9. Especially during the closing credits you can see that it's positioned so the end of the main mast boom could rest in one of the 3 notches on top of the "roll bar" (what's it really called?) Also the helmsman does not need to duck to avoid the swinging boom because it would hit that structure.
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