Would it be madness

[lw395]

No, I've never used a hand bearing compass from a car either. I can see the similarity between driving and sailing here....I've not completed a cross channel passage yet but certainly in the Solent one sails like one drives....attentively! If I was to cross a shipping lane in open sea I would probably maintain a constant watch.....but maybe the length of time that full attention is required to cross a shipping lane is the issue here....so to ask the OP about crew is very pertinent....perhaps the OP's question could have been "if I am unable to maintain a constant watch whilst crossing the channel is AIS a necessity?"

If you can't keep an adequate visual watch, then fiddling with AIS is probably not going to help much.
Crossing the channel you do not need to stare at the horizon 60 seconds in every minute. You need to look 360 degrees around you often enough. If visibility is say 10 miles, you need to be thinking about seeing big ships before they get to say 5 miles. A ship doing 20 knots will get 5 miles closer in 15 minutes. As a minimum I like to scan the whole horizon every 5 minutes.

 

[johnalison]

I'm interested in those who use a hand-bearing compass to determine whether another vessel is crossing or not. I've always either sighted against the land or other background object, or (when steering a compass course on autopilot) sighted from a fixed point on the boat to see whether the target moves against a point on the boat. Either is more sensitive than a hand-bearing compass, where at best you have an accuracy of 1 degree (usually less under conditions other than flat calm!). A degree is twice the width of the moon, so you can easily see changes in bearing less than that by sighting against other objects. Clearly sighting against a distant object is better, but under autopilot the course is maintained quite accurately, and sighting against a fixed point on the boat (usually a point well forward) it works satisfactorily as long as you can find a reliable position where you can fix the position of your head.

Sighting against the land is not an accurate way of determining if a collision risk exists, though it provides an approximation, just as projecting a course from your tidal offset to your destination is only roughly right.

I agree that using a compass is not usually helpful. I would normally have one to hand when crossing shipping, and although I would use it I have been disappointed by the results of my efforts. By the time that I am confident of a change in bearing, my eyes will usually have already seen a change in the ship's aspect and given me the information I need. I still think that we should use all the means at our disposal to assess the situation and endeavour to acquire and maintain our skills.

I suspect that the OP will be far safer on his proposed crossing than the bunch of complacent old fogeys that most of us represent.

 

[rib]

Can you land pet dogs on alderney ?

 

[ghostlymoron]

Can't see how this works. Won't they move relatively due to the movement of your own boat?

I'm interested in those who use a hand-bearing compassg3qZwVsj to determine whether another vessel is crossing or not. I've always either sighted against the land or other background object, or (when steering a compass course on autopilot) sighted from a fixed point on the boat to see whether the target moves against a point on the boat. Either is more sensitive than a hand-bearing compass, where at best you have an accuracy of 1 degree (usually less under conditions other than flat calm!). A degree is twice the width of the moon, so you can easily see changes in bearing less than that by sighting against other objects. Clearly sighting against a distant object is better, but under autopilot the course is maintained quite accurately, and sighting against a fixed point on the boat (usually a point well forward) it works satisfactorily as long as you can find a reliable position where you can fix the position of your head.

 

[Seajet]

Can you land pet dogs on alderney ?

What with, a rocket and parachute while going down the Swinge to Guernsey ?

I always favour bino''s with a compass nowadays, if I really have to start considering the closing bearing of a ship I make a very obvious course change and go behind them - with the best radar reflector or AIS in the world I reckon a good 50% wouldn't know you were there anyway.

 

[AntarcticPilot]

Can't see how this works. Won't they move relatively due to the movement of your own boat?

Just as they do when using a hand-bearing compass! The point is that you are determining the RELATIVE motion of a crossing vessel and your boat. Using motion against a distant background is only a more sensitive way of seeing the change of bearing that a hand-bearing compass measures; doing the same with respect to your own vessel does assume that you are holding a constant heading, which is why I suggested it would work better under auto-pilot, where the heading tends to be held better than manual steering can manage (I would trust it if I was steering !).

Please note that I say a distant background, though.

 

[ghostlymoron]

But a bearing on a background object will change as you move. I sight past an object on my boat say a stantion or something. If it moves forward or aft your ok (preferably forward).

 

[AntarcticPilot]

But a bearing on a background object will change as you move. I sight past an object on my boat say a stantion or something. If it moves forward or aft your ok (preferably forward).

That's why I said distant; that is. many times further away than the ship being observed. Even clouds can work; they are far enough away that their own motion isn't significant in less than gale-force conditions. It it the relative radial velocity that matter, and as long as you're comparing with something whose relative radial velocity is small, it works. The further away the background, the better. However, if you have good spatial judgement, you can take the relative motion of foreground and background into account.

 

[rib]

Me i cant see no back ground in the dark,i use compass ,practise makes for less mistakes use during day be better at night
,

 

[DownWest]

Did DR from Crouch to Alderney with stops at Dover and Newhaven, back in '63. Gale on the nose and reached Alderney after the tide had turned. Spent a night tacking off there until daylight when we could get in.
Modern nav would have made it far easier. Not worried about distress beacons, just get on with it. We saw a few ships, but no conflict.

The quote about the Alderney residents being a 'Bunch of Drunkards Clinging to a Rock' was current then & attributed to Gurnsey.

 

[AntarcticPilot]

Me i cant see no back ground in the dark,i use compass ,practise makes for less mistakes use during day be better at night
,

Good point. I havn'tdone much night sailing, but when I have, I have found that it is never that dark, though.

 

[rib]

Same applys in hazy/bad vis.bit like radar if you practise when you can see your better at it when you cant well at least i am even when its a bit rolly ?