Ramsgate to Harwich

spottydog

spottydog

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Fetching the boat back from Ramsgate tonight. ( HW 0230 ) Going to use the Fishermans Gat, Black Deep route. Done the trip a number of times in daylight but not at night. Anyone with thoughts on the wisdom or otherwise of the route. A suggestion made was go on the outside route. My thoughts are there are fewer lit buoys and no shelter from the Easterlies induced chop. All comments wellcome particularly those telling me to stay at home in a warm and comfortable bed.
 
Been across at night, in strong Swers and took the outside route. Last came across in Sept in strong SWers again and took the Fishermans etc route. Fishermans is well lit, and with easterlies should be a simple trip. I doubt that either route will keep you out of the chop. I'd look at the tides and see which route gives you the least foul tide. Plugging around the outside with the full flood to 02:30 may not be appealing.
 
I am sorry - I apologise to the Forum for what I am about to do but I couldn't resist using my passage planning tables for Crossing the Thames Estuary (currently with Imray for publication in the spring).

Life's a compromise. Be outside Ramsgate at midnight, using the Foulgers Gat, Black Deep route you should at an average of 5 kts be at Cliff Foot SHM at about 7.49am! It'll be slower than the best tide effect up to the North Foreland but you'll keep the the ebb all the way to Cliff Foot. Want the best speed up to the North Foreland, be outside Ramsgate at 0426 but you'll lose the ebb and won't get to the Cliff Foot until 2pm as you'll hit the flood.

Best speed down the Black Deep would be to be at the Long Sand Inner at HW Sheerness +1 ie 0426. Which means being outside Ramsgate at HW Sheerness - 2.30 ie 0100hrs (HW tonight is 0326 GMT). Should get to Cliff Foot at HW Sheerness +4.55 or 08.21 which is the quickest overall passage I can make it on the planning tables. I make the 0100 start an expected 427 minutes duration; the midnight start 449 minutes. There is little difference in the speed up to th North Foreland but the extra tidal rate in the Black Deep makes the extra saving on time. The 0420 start would be at least 460 minutes, probably more like 490 so picking the quick time up to the North Foreland is no use for this journey.

All times in GMT and refer to HW Sheerness. Can do it for 3, 4, 6 or 7 knots as well. Do you have any criteria?

There now. Have I made a mistake? Dare I hit the send button?

I'm sorry to have advertised.
 
Oh dear - I can't resist another advert. It's all in an A4 sized book - well it will be. It all started on a wet Thursday in November with TG laid up. 32 routes across the Estuary between Ramsgate, the Kent, Essex and Suffolk Rivers - through the sands not outside (for Harwich) - sorry got to stop somewhere for the publishers. Basically I selected the common routes, broke them down into sectors effectively representing the changes in course and then calculated in tables the time necessary to complete each sector every 15 minutes of the day allowing for the tide. There will be tables for Springs and Neaps, 'there and back' for average speeds of 3, 4, 5, 6, 7. So to provide the data above took 10 minutes (inc SWMBO arriving with a cup of tea and a 'you're at that d*** book again!).

I am currently toying with a website from which you can download Course to Steer data for each sector of all the routes for every 15 minutes of th day. Done the work but its too many pages for a book.
 
Tillergirl thanks for the exellently detailed reply ( I will be first in line for the planner ). sadly it was all to no avail last night. We arrived at Ramsgate at about 22:00 but the conditions were too bad to consider making the trip, got home at 03:15 this morning, boat still in Ramsgate!!!!! So I will have to await the next suitable window to make the passage. /forums/images/graemlins/frown.gif
 
Probably a wise decision. Doesn't feel too pleasant here today and last night the cat wouldn't go out which is a major clue!

The data will work for the next time, all you have to do is refer it to HW Sheerness times. Is 5 knots the speed you would aim average for planning purposes or do you want another?
 
Keys always available for willing hands. I sail singlehanded through the summer but prefer others onboard this time of year.
 
5 knots is about right although it,s always best, I find, to err on the side of realism - 4knts
To hell with the normal protocols re advertising on the forum tell us all about the book It,s sounds the dogs doobries for us estuary crawlers /forums/images/graemlins/grin.gif
 
I don't think anyone here is going to complain about advertising something as potentially useful as that , sounds to me to be something I would be very interested to hear about , so as the others have already said , advertise away . Come on , tell us more /forums/images/graemlins/smile.gif
 
You are too kind. A little bit more then.

It all started with a personal plan to produce some passage planning tables for Ramsgate to the Blackwater and then encouragement from the trio of authors of East Coast Pilot and particularly Colin Jarman who was very helpful, turned it into what it will be.

As you know, the Thames Estuary is difficult to cross on a favourable tide all the way. Get the best tide up from Ramsgate and, depending on the journey, you've lost the tide before you finish and can face hours of ebb out of one of the Rivers. Do you want to cross, for example, the Sunk on a rising tide or be at a point at the start of the flood. So the idea was to find a way to ease these calculations.

So I picked 32 Routes of which 18 are between Ramsgate and the Swale, Medway, Crouch, Blackwater, Colne, Harwich Harbour and the Deben including three choices across the Long and Sunk Sands for the Essex Rivers and either a Black Deep or East Swin route for the Suffolk Rivers. The other 14 routes are from the Kent Rivers (Swale and Medway) to the Crouch, Blackwater, Colne, Harwich and Deben using either the Barrow or West Swin. I simply had to draw the line there and omit the outside routes to Harwich and some of the simpler journeys between each of the Essex Rivers, between the two Kent Rivers and ditto Suffolk. There would be no trouble including these; its simply space. More pages mean a higher cover price.

The routes are broken down into sectors. Every time there is a course change, there is a new sector plus there are one or two sectors split into two because of their length so as to use separate tidal data. There are 50 pages of comment/guidance on the routes and each sector. One of the hardest bits was reducing undue repetition and only your feedback in due course will tell me if I've got that right as certain sectors feature in more than one route: for example Ramsgate to the Black Deep is the same whether you are heading for the Essex Rivers or the Suffolk Rivers (there are choices for usisng either Fisherman's Gat or Foulgers Gat; indeed the North Edinburgh is also in there). A guide gives you the sectors for your chosen route - from there you go to the tables to do your passage planning. First let me explain there are tables for Springs and Neaps, North and Southwards (or East and Westwards in the case of the Medway and Swale to Ramsgate) and these are repeated each for 3, 4, 5, 6 and 7 knots. Again I could do more but you have to stop somewhere and that accounts for 100 pages of tables now!

I hope the cunning secret is in the layout of the tables. First everything is related to High Water Sheerness (gave me some fun interpolating times from Dover and Harwich based data!) although you can of course simply factor in the time differences of Sheerness if all you have is say HW Dover times (differences are listed). For each sector the duration in minutes is shown allowing for boat speed and tide effect for each 15 minutes of the day: so it is (sorry the forum doesn't do columns properly)

Time Duration Time at end of Sector

-6.00 85 - 4.36
-5.45 84 - 4.21
-5.30 82 - 4.08
-5.15 81 - 3.54
-5.00 80 - 3.40

This set of data is repeated for each sector so if we start this sector at -6.00 (six hours before HW Sheerness) and we will arrive if we have kept to our average speed at our destination waypoint (the start point for the next sector) at - 4.36. Simply move to the next column in the tables (not shown here) and go down the time column for the value closest to -4.36 (-4.30 obviously), read off the duration and 'Time at end of sector' value and you have the tide effect calculated for you.

Move onto the next sector and so on until you reach your destination. You can scan down the duration column to easily see the quickest times and therefore when the tide is favourable. If you want to be at the Sunk Sand let us say when the tide is just starting to rise, get to the column for that sector and find the value for say +1.00 and by working the column backwards and forwards from that point you can set your start time and find the estiamted time of arrival. This enables you to plan the journey any which way you want - start in daylight, arrive in daylight - whatever you like.

It is far more complicated to describe than use. It took me about ten minutes to scan the tables and pick on and work through the alternatives described above without rushing.

I use 45 Waypoints to create 60 sectors for the 32 routes. I best not post the image without Imrays permission as its theirs. To cross the Long Sand, there are alternatives via the North Edinburgh, Fishermans Gat and Foulger's Gat. To cross the Sunk Sand, I've included the SW Sunk, the Sunk Beacon and the 'Barrow No 2' crossing. There are obviously very heavy warnings about the SW Sunk and I only included it because before the beacon fell over I went down there (and the Sunk Beacon) to do a bit of surveying to find where the best water was; and because at the time of finishing the draft I hoped naively that the wreakage might be cleared.

My original plan was to include course to steer data but you East Coast navigators will know that mathematically it is impossible to arrive an answer using the single correction method (all the tide data plotted from start point and CtS line drawn from that end to destination). This is because at the end of the day, you are left trying to calculate the values of a Trapezoid which can't be done. I could however calculate CtS using the multi-correction method (a plot for each hour or part of an hour) but that produces too much data for a printed book. For example for every fifteen minutes of the day, for every sector, for every average speed, for Springs and for Neaps, for Northwards and Southwards amounts to 640 pages! Dead easy to produce believe it or not, hence me thinking about making these available as a download from my own website. I have to cover this with Imray but I think it can be harmoniously done. So you could for example chose to download a bundle of pages to cover all the Ramsgate to Essex Rivers routes for 5 knots or the Suffolk River routes for 7 kts.

The advantage of these tables is that you can use them according to your progress - the book will show whether a bit of motor sailing is worthwhile to speed up a particular part of your passage - the download tables would give every CtS for every 15 mintues so if you are delayed or faster on one sector you can just read off the right data for the next sector within seconds. Of course with you experienced chaps I don't need to explain that a proper CtS is much better than trying to keep on the track by keeping Xtrack error to Zero.

So there we are. I should have got it ready for last year but hit other commitments. Imray are talking about a spring publication date and from my point of view the work is finished and they have all the draft material. I have no idea how much they intend to charge but I know from their guidance on overall size that they understand the need for it to be affordable.

It is entirely compatible with East Coast Pilot although for a variety of reasons my 'Landfall' Waypoints are not the same as those Colin, Dick and Garth use. I regret that but my mesh of sectors becomes too complicated if I use their Waypoints. That said for practical purposes in good vis, as you arrive at 'my' Landfalls, their pilotage guidance is very adjacent.

Are there more? Well certainly I can see a Channel Island replica (although I wonder how many spreadsheet columns behind the scenes it will take to get through the Alderney Race at 3 knts against the tide!). I have also given some thought to an Eastern Channel crossing eg North Foreland, Ramsgate and Dover to Boulogne, Calais, Dunkerque etc inside and outside the Goodwins. The mathematical challenge there is the obligatory heading over the shipping lanes. Rather than a static sector, this would 'move' its start and finish points according to the tide so the preceding and subsequent sector is fixed at one end and moving at the other so to speak. Dead easy to calculate for any particular example but putting the variations into a book for easy reading is quite challenging. What about longer North Sea passages? Frankly I'm not sure, what do you all think?

As to other possibilities, I think the issue is about the complexity of the navigation and tides so I'm not sure how viable other routes are. The Thames Estuary does at least lend itself to fixed routes within certain limits which makes this viable. Otherwise the infinite possibilities of choice just give too many variables.

Sorry to have gone on so long but I hope that since most of us at laid up this is of at least a little interest.
 
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