Free Supplement to the Second Edition: Supplement No 2A – Dover to Ramsgate Sectors and TSS Offset Distances at the Dover Straits
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Free Supplement to the Second Edition: Supplement No 2a – Dover to Ramsgate sectors and TSS Offset distances at the Dover Straits Crossing the Thames Estuary is published by Imray, Laurie & Wilson Ltd Wych House, St Ives, Cambridgeshire, PE27 5BT, England +44(0)1480 462114 Email: [email protected] www.imray.com First edition 2008 Second edition 2014 This document is the Supplement No 2a published by R Gaspar (2016) www.crossingthethamesestuary.com All rights reserved. No part of this publication, Supplement No 2a, may be reproduced, transmitted or used in any form by any means graphic, electronic or mechanical, including photocopying, recording, taping or information storage and retrieval systems or otherwise without the prior permission of the publisher except where a reader has purchased a copy of the second edition of Crossing the Thames Estuary. © R Gaspar 2016 Roger Gaspar has asserted his right under the Copyright, Designs and Patents Act 1988 to be identified as the author of this Supplement No 2a CAUTION Every effort has been made to ensure the accuracy of this Supplement No 2a. It contains selected information and thus is not definitive and does not include all known information on the subject in hand; this is particularly relevant to the plans, which should not be used for navigation. The author believes that his selection is a useful aid to prudent navigation, but the safety of a vessel depends ultimately on the judgement of the navigator, who should access all information, published or unpublished. PLANS The plans in this supplement No 2a are not to be used for navigation. They are designed to support the text and should at all times be used with navigational charts. Note Supplement 2a includes one typo correction. Imray have kindly given permission to allow drawings to be based on their material. Dover to Ramsgate and Offsets at the TSS at the Dover Straits Introduction This supplement needs some explanation but I hope it is not over tedious! This includes two components: a set of regular tables of new sectors to extent Ramsgate to Dover and the beginning of the Dover Straits Traffic Separation Scheme, and, an entirely new and unique set of tables providing the ‘offset’ when crossing the TSS1. I will explain! Dover and the TSS to Ramsgate Sectors Some conversations in 2015 prompted me to add sectors between Dover and Ramsgate. Crossing the Estuary from Dover to the North or vice versa is always significantly longer because the strength of the tides between the South Foreland and Ramsgate. Passage from or to Dover across the Estuary can challenge the best fit from the Essex and Suffolk rivers. So if you are coming up or down the Channel or across the Dover Straits, these new sectors can help choices; coming up the Channel, do I want to stop at Dover or carry on to Ramsgate? If I am crossing the TSS at the Dover Straits, how long or what is the best time to make towards or from Ramsgate. Ramsgate as a destination or starting port across the Estuary, gives more flexible choices than Dover and avoids less adverse tide across the Estuary to or from Dover particularly with lower boat average speeds. Dover is not impossible across the Estuary, timing is perhaps more careful so the new sectors can assist readers. You may be wondering why I did not complete full routes across the Dover Straits, say, to Calais or Boulogne or indeed the Ramsgate to Calais via outside Sectors from Dover or the TSS to Ramsgate the Goodwin Sands. It could be done but a rigid route south side of the TSS is 1 TSS – Traffic Separation Scheme: one way traffic lanes with separation zone or line © R. Gaspar, 2016. www.crossingthethamesestuary.com 1 the best. Both French ports will have strong ‘up and down’ tides so there is flexibility to choose where you want to start to cross the TSS. For this reason the waypoints selected on the north side of the TSS are notional. The Sectors and Waypoints There are three choices of routes: Dover to or from Ramsgate, the western side of the Dover Straits TSS to or from Ramsgate or eastern side of the Dover Straits TSS to or from Ramsgate. The detail of sectors and waypoints follow a short summary. Route ‐ Dover to or from Ramsgate – 14.58nm This route is obviously directly from port to port but it could also be used coming further from the western side of the English Channel. It has three sectors – Sectors W1, from Dover to a waypoint off the South Foreland, Sector W2, from the South Foreland waypoint to a waypoint at the Downs, and Sector W3, the Downs to the Ramsgate Approach Channel. The route benefits (or suffers) from high tidal rates and in particular just off the western entrance of Dover, tides HW+1 on springs can reach 4.1knots to the north‐east. Of course, excellent progress will get round to Ramsgate but beware of such tidal rates. Immediately outside the western entrance where the breakwater intrudes into the tidal flow can make lively waters and against the wind positively nasty! I have been told that leisure craft may sometimes be given permission to leave the eastern entrance so contact with the Port may be beneficial. Approaching Dover to or from the west in the Channel slightly further out will benefit from calmer waters clear of the breakwater (and clear of shipping) and slightly tidal rates. The tables give good warning: Beneficial tide in Sector W1 at 4kts boat speed on springs can complete the 4.26nm sector in 30 minutes going with the best tidal rates. Conversely up to 2 hours 36 minutes for the Sector can be the worst against the tide! Sector W1 Dover to South Foreland Wpt.68 Off Dover Harbour Entrance 51˚06’70N, 001˚19’85E 054˚(T) Northbound 4.26 nm Wpt. 69 Off the South Foreland 51˚09'19N, 001˚25'34E 234˚(T) Southbound Sector W2 South Foreland to The Downs Route Wpt. 69 Off the South Foreland 51˚09'19N, 001˚25'34E 006˚(T) Northbound 5.34 nm Dover to Ramsgate Wpt. 70 The Downs 51˚14’50N, 001˚26’24E 186˚(T) Southbound Sector W3 The Downs to Ramsgate Approach Channel Wpt 70 The Downs 51˚14’50N, 001˚26’24E 008˚(T) Northbound 4.98 nm Wpt. 71 Ramsgate Approach 51˚19’43N, 001˚27’35E 188˚(T) Southbound © R. Gaspar, 2016. www.crossingthethamesestuary.com 2 These tables are particularly useful in judging whether to keep on round to Ramsgate when come up from the west of the Channel or whether to complete a full crossing of the Estuary is better starting from Ramsgate or Dover. Route ‐ the western side of the Dover Straits to or from Ramsgate – 16.01nm This route is using a waypoint at the north edge of the Traffic Separation Scheme (TSS) towards the western side of the Dover Straits. This benefits heading to or from Boulogne. Heading south it naturally follows the south‐west tidal flow from Ramsgate, across the TSS (following the Collision Regulations at a heading of right angles but benefitting from a south‐westerly slant) and finally once clear south of the TSS to get the end of the same tidal flow down to Boulogne. Getting the opposite tidal flow gives help from Boulogne up to Ramsgate. Again there are three sectors: Sector W4 from the north edge of the TSS to the waypoint off the South Foreland, and then from the same two Sectors W2 and W3 to connection up from the South Foreland waypoint via the Downs to the Ramsgate Approach. The waypoint at the north edge of the TSS is fixed for the Sector. However, the slant or ‘offset’ across the TSS may make sense to adjust the positon of this waypoint along up or down the edge of the TSS, particularly at different boat speed average rates. As a passage planning assumption, an adjustment of this waypoint will still retain the Table as viable data. An explanation of the second set of tables providing the slant or ‘offset’ follows shortly. Sector W1 Dover to South Foreland Wpt.72 Northern edge of the TSS 51˚03’53N, 001˚24’44E 006˚(T) Northbound 5.69 nm Route Wpt. 69 Off the South Foreland 51˚09'19N, 001˚25'34E 186˚(T) Southbound Sector W2 South Foreland to The Downs Northern Edge of the TSS (towards the Wpt. 69 Off the South Foreland 51˚09'19N, 001˚25'34E 006˚(T) Northbound 5.34 nm western side of the Wpt. 70 The Downs 51˚14’50N, 001˚26’24E 186˚(T) Southbound Dover Straits) to Sector W3 The Downs to Ramsgate Approach Channel Ramsgate Wpt 70 The Downs 51˚14’50N, 001˚26’24E 008˚(T) Northbound 4.98 nm Wpt. 71 Ramsgate Approach 51˚19’43N, 001˚27’35E 188˚(T) Southbound Route – the eastern side of the Dover Straits to or from Ramsgate – 13.41nm This third route is intended as a route towards Calais using inside the Goodwin Sands. Different intentions for Calais rather than Boulogne require crossing the TSS further towards the east. So a different waypoint from the northern edge of the waypoint lies south‐west of the SW Goodwin cardinal buoy. As before in the previous route, the waypoint may benefit sliding up or down the edge of the TSS. © R. Gaspar, 2016. www.crossingthethamesestuary.com 3 The three sectors are: Sector W5, a short rhumb line from the edge of the north of the TSS to the SW Goodwin, Sector W6 from the SW Goodwin to the waypoint at the Downs and then the same final sector W3.