Heights and depths.

[Mudisox]

Having just laboured through the posts on whether the chart symbols will tell us whether one can get under a bridge, I was wondering just how many times one has to do the necessary calculation that seems to be an RYA favourite.
For myself I've only approached slowly, against the ebb tide the bridge to enter the Penze river, only to back off, when the vhf aerial starting to touch.
So any others out there for real?

 

[AntarcticPilot]

Having just laboured through the posts on whether the chart symbols will tell us whether one can get under a bridge, I was wondering just how many times one has to do the necessary calculation that seems to be an RYA favourite.
For myself I've only approached slowly, against the ebb tide the bridge to enter the Penze river, only to back off, when the vhf aerial starting to touch.
So any others out there for real?

If it's close enough to need careful calculation, I don't go there.

 

[OGITD]

Me too!

If it's close enough to need careful calculation, I don't go there.

+1

I was never part of any Navy Mathematics Squad….. but even they get it drastically wrong sometimes. (pink spinnaker, red tanker, Solent, on YouTube ring any bells).... .... so! who's still buying the beer for this one?

 

[onesea]

If it's close enough to need careful calculation, I don't go there.

+1 Or go gently and make sure its a rising tide, if I am going to touch bottom.

 

[alteredoutlook]

How many people actually know the height of their mast??

It was only in Sweden and Norway last year that I required to do so to get under the bridges that cross the fjords

 

[sailorman]

How many people actually know the height of their mast??

It was only in Sweden and Norway last year that I required to do so to get under the bridges that cross the fjords

16.2m from the water

 

[Elessar]

How many people actually know the height of their mast??

It was only in Sweden and Norway last year that I required to do so to get under the bridges that cross the fjords

when I'm in a saily boat and have to go under a bridge, even when there's oodles of space calculated, it still gives me the chills and looks like it's going to be close. If you are going to hit it is bound to be obvious surely?

Summer before last holiday we did Marlow Southampton via Oxford and Cherbourg in our mobo. Some bridges were so tight I had to climb to get my eye level with the top of the radar, to see if I could see the underside of the bridge or not. If you can of course, you will get under. That is easy on most mobos, bit tricky on a yacht. I've had to wait at Hammersmith bridge quite a few times and go under with a clearance far too close to rely on calculation.
However calculation means you have a 10 min wait, not hours.

Having said that I did a few thousand miles this year in a mobo with a 10.3m air draft, some masts aren't that high!

 

[exfinnsailor]

16.2m from the water

Does that include the ariel and wind vane

 

[sailorman]

Does that include the ariel and wind vane

you guess

 

[VicS]

Does that include the ariel and wind vane

Ariel ??

.... or

 

[sailorman]

not a sq 4 then

 

[VicS]

not a sq 4 then

Too heavy for the mast head

 

[sailorman]

Too heavy for the mast head

when we were young my mate had a sq4 with a chair to make it legal

 

[prv]

How many people actually know the height of their mast??

Mine's 27 feet near as dammit, which I know cos it hangs 3 foot over the stern when I have it up on its stands with the foot directly above the bow.

Got to add another 3 foot or so for the height of the step off the water, of course.

Pete

 

[VicS]

I dont think I am likely to be taking my boat under any bridges that will give rsie to any doubts.

Interesting about the bridge over the Penze river. There was time when i was suggesting we went to the Penze river in the Berwick... I was not aware that there was a bridge across it!

 

[Billjratt]

The stuff at the top of the mast is too flimsy and useful to jeapordise by jousting with bridges, cables or even trees. I gather this is what passage planning should be about.
I take it all you chancers have a spare/emergency VHF motorbike with appropriate lights on board, wired and ready to go?
Better leave the goggles off to feel the breeze if the anemometer gets it as well.

 

[prv]

The stuff at the top of the mast is too flimsy and useful to jeapordise by jousting with bridges, cables or even trees.

Only thing at the top of my mast is a burgee made of a garden cane and an old coathanger.

Pete

 

[Beadle]

when I'm in a saily boat and have to go under a bridge, even when there's oodles of space calculated, it still gives me the chills and looks like it's going to be close. If you are going to hit it is bound to be obvious surely?

Summer before last holiday we did Marlow Southampton via Oxford and Cherbourg in our mobo. Some bridges were so tight I had to climb to get my eye level with the top of the radar, to see if I could see the underside of the bridge or not. If you can of course, you will get under. That is easy on most mobos, bit tricky on a yacht. I've had to wait at Hammersmith bridge quite a few times and go under with a clearance far too close to rely on calculation.
However calculation means you have a 10 min wait, not hours.

Having said that I did a few thousand miles this year in a mobo with a 10.3m air draft, some masts aren't that high!

If going under a bridge causes the old sphincter muscles to twitch a bit you really must try going under HV power lines. 440 kV down the mast could ruin your whole day.

It would certainly make your eyes light up.