une mer forte de 3/4 avant

08:54 Nov 8, 2014 

It's about a Motor Yacht (catamaran).

19:28 Nov 7, 2014 

Could you please specify if the text is about a large ship, or is it about a yacht, a sailboat?

18:36 Nov 7, 2014 

Well, I'm very far from being as expert as most of the contributors here, but I just find "3/4" an odd way to express anything other than ... "three quarters"! I think the French expression "trois quarts" is of course quite a different matter...

So I'm only really looking at it from a purely linguistic (and thus simplistic!) point of view; to go back to my analogy of a portrait description, which appears on the face of it equally illogical: a full profile would mean facing @ 90° to the camera, compared to a front-on shot; but AFAIK, a "3/4 profile" means 'with the head turned half towards the side — i.e. at 45°. Even if I am mistaken, and that was a "½ profile", then a 3/4 profile would be one where the head was turned 22.5° — or 67.5°? Either way, I instinctively read this as being 'some way off straight ahead'; but then again, maybe I'd be the one over there on the rocks ;-)

18:08 Nov 7, 2014 

I confess I struggle to understand what 'three quarters' could mean. Three quarters of what?
Florence suggests 'broad on the bow'. I believe it's a heavy sea from a fine angle off the bow.
Another reference to 'trois quarts' meaning 'three points', in the context of drift:
"... si le vent vient de trois quarts avant, il reculera dans la même direction, comme le ferait un objet quelconque flottant à la surface de l'eau, à condition, bien entendu, que le courant soit nul." http://perso.numericable.fr/cf50/articles/1951/1951414B.htm

18:04 Nov 7, 2014 

Thanks.
So is it possible that the French is ambiguous, and it could mean either?

17:54 Nov 7, 2014 

I believe Florence has come closest to the correct technical description, which is pretty close to my own (less expert!) opinion; my only query is with the 3/4, which I believe stands for 'three-quarters' rather than '3 or 4 compass points'

17:54 Nov 7, 2014 

I agree, Florence, that 'a heavy sea' may be better than 'a heavy swell'. That is also why I gave the two options in my explanation of my answer.
Definition of swell: "A swell, in the context of an ocean, sea or lake, is a series of mechanical waves that propagate along the interface between water and air and so they are often referred to as surface gravity waves. These series of surface gravity waves are not generated by the immediate local wind, instead by distant weather systems, where wind blows for a duration of time over a fetch of water. This is the primary definition of a swell as opposed to a locally generated wind wave, which is still under the influence of the mechanisms that created it, e.g. wind blowing over a puddle. More generally, a swell consists of wind-generated waves that are not—or are hardly—affected by the local wind at that time. Swell waves often have a long wavelength but this varies due to the size, strength and duration of the weather system responsible for the swell and the size of the water body, e.g. wavelengths are rarely more than 150 m in the Mediterranean." http://en.wikipedia.org/wiki/Swell_(ocean)

17:06 Nov 7, 2014 

swell c'est la houle ce qui est different de mer forte.. on peut ne pas avoir de vague et une grosse houle ou le contraire...

une mer forte c'est une mer force 5 dans la table descriptive de l'état de la mer hauteur des vagues de 2,5 m à 4 m..

15:24 Nov 7, 2014 

"Close" generally means nearer to dead ahead. "Broad" is further away from dead ahead. Take the example of a "beam reach", i.e. when the wind is blowing perpendicular to the centre line of the boat. A "close reach" is when the wind comes from forward of the perpendicular (i.e. from nearer the bow) and with a "broad reach", the wind blows from aft of the perpendicular (i.e. from nearer the stern). If Florence is right in assuming that the 3/4 refers to the number of points on the bow, this means that the swell is coming from less than 45 degrees from the bow (see my other discussion entry), i.e. it is "close on the bow".

14:48 Nov 7, 2014 

If that's the case, and it seems logical, why have you agreed with Florence's answer? Just wondered...

12:14 Nov 7, 2014 

"3/4 on the bow" is the same idea as a "3/4 profile photograph" etc.?

Although I'm not familiar with this particular term used in this nautical context, I'd have understood it as meaning 'coming at us at around 45°' — 90° would of course be 'abaft the beam' and 180° would be 'astern'.

There are some good glossaries out there for that sort of term, i'll see if I can find one for you quickly...

One I found seemed to be quoting 'official' met office sea terminology, and gave it as 'rough sea'

12:10 Nov 7, 2014 

"...every forty-five degrees of direction ... was divided into four 'points'. Thus, 32 points of 11.25° each makes a circle of 360°." (http://en.wikipedia.org/wiki/Bearing_(navigation)) As I understand it, three points out of four in this context would mean about 33.75 degrees away from dead ahead, which suggests that the sea is close on the bow, rather than broad. But please correct me if I'm wrong.