Trainee Engineer

[colinb]

Hi all, I have a rather large problem, that will be a challenge to all!! I wish to buy a yacht 40-45 foot and moor it in our local waterway 200m from home. The problem is someone built a bridge with only 5 m clearance between the passage and the open ocean. Avoiding blowing up the bridge, does anyone have a concept for a lowerable mast (hydraulic), Telescopic mast and rigging etc, to solve this problem? Any help or tips would be appreciated. Of course I could always move to the other side of the bridge, but that would be to easy!!!!!!

[whoosh]

the only way really is a strong taberacle, , solid plates each side of mast, with stout pin at about a metre height to pivot from
the ram force reqd is a lot, and could be calculated by someone like Ric W HERE, But you need a very strong deck and anchor point for the ram
Best suited to a yacht of metal build although possiblefor any given sound engineering practice
you could tacke from an anchor capstan or tackle back to a sheet winch

[PAR]

Tabernacles have been used for hundreds of years and without hydraulic assist. I've seen very tall masts lowered with one hand pressure.

Of course as Whoosh (the noise that occurs when he takes his hands off his ears) has pointed out, you'll need some engineering and modifications to your boat and rig.

I did one recently on a 24' sloop and used the boom vang tackle to easily raise and lower the stick.

Telescoping masts should be left to the special effects guys on big budget movies.

(couldn't resist Stewart)