Arwen's meanderings

Hi everyone and welcome to my dinghy cruising blog about my John Welsford designed 'navigator' named Arwen. Built over three years, Arwen was launched in August 2007. She is a standing lug yawl 14' 6" in length. This blog records our dinghy cruising voyages together around the coastal waters of SW England.
Arwen has an associated YouTube channel so visit www.YouTube.com/c/plymouthwelshboy to find our most recent cruises and click subscribe.
On this blog you will find posts about dinghy cruising locations, accounts of our voyages, maintenance tips and 'How to's' ranging from rigging standing lug sails and building galley boxes to using 'anchor buddies' and creating 'pilotage notes'. I hope you find something that inspires you to get out on the water in your boat. Drop us a comment and happy sailing.
Steve and Arwen

Sunday 22 September 2013

Passage planning and safety thoughts


In learned something new today......"lee bowing". I'd not heard the term before but now I have briefly read up on it I can see it makes sense. Apparently when approaching the shore you try to get things in such a way that the wind is blowing on the windward bow but the tide is pushing against the lee bow. In this way you will not drift too far along the coastline in either direction from your intended mark.

I've been thinking about longer distance sailing again. Didn't do much this summer but I am wondering about a couple of weekend voyages in the not too distant future. SOLAS regulations state you should take into account weather, tides, limitations of the vessel and her crew, navigational dangers and a contingency plan in case things go wrong.

Anyway I started to think that actually having some lists drawn up to help my thinking might be useful. So for my passage planning checklist I guess it might cover the following

- my charts
- tidal stream data from my small boats almanac
- port details for all the ports I will or may have to call in

Then with a more detailed view in mind
- passage plan review on small scale charts
- any inshore passages, most of mine would be
- sunrise, sunset, daylight hours times
- tidal ranges, springs or neaps, direction of tides to avoid foul tide streams, ETA's at various places along a tidal flow/stream
- weather patterns in the lead up to departure along with latest forecasts and details about where to get different forecast updates whilst on passage
- pilotage plans for ports visiting both entry and exit
- filling in my passage plan tables with notes about courses, waypoints etc
- programming the GPS with waypoints
- working out minimum times to get between waypoints and whether these are achievable given latest forecasts
- dangers to be avoided including distances off rock marks, shoals, wrecks etc
- working out clearing bearings for above and any headlands on route
- identifying sheltered refuges and their entry points

After all this I guess it is a matter of checking boat safety equipment. I use the Dinghy Cruising Association safety guidelines. Then checking the supplies needed for the passage. This includes catering (food, water, cooking equipment, cooking fuel, rubbish disposal, cleaning equipment) and things for boat (spare fuel, outboard toolkit, spare rigging equipment and hardware etc).

Then there is sorting out my SPOT PLB including the tracking page and notifying the coastguard and my nominated safety people, including leaving a copy of passage plans with my close friend who is an excellent small boat sailor.

Finally, out of paranoia, a final check of the passage plan against chart and an ordnance survey mark, circling any noticeable landmarks that can be used as checkpoints on the way. At this point I often annotate my charts with courses, bearings, tidal heights etc. I also draw up any tidal port height charts.

I also came across an interesting article in October's PBO magazine by Sticky Stapylton, a yacht master ocean ticket holder and RYAN yachtmaster instructor. He has a few handy little tips. One is taking account of high and low pressure and the impact it will have on tidal heights. To what extent it would affect me and Arwen I don't know but he argued that a change of one millibar leads to a change of sea level by 1 centimetre. He had a chart which he used to calculate such changes and it goes like this.....

963mb.    +0.5m
983mb.    +0.2m
1003mb.  +0.1m
1013mb.  0
1023mb.  - 0.1m
1043mb.  - 0.3m

He has a similar chart for converting the rule of 12ths into %s as well. Very useful.

He also made some interesting checklists about what to do in heavy weather. His advice included
- not planning passages so that ports of refuge are on lee shores or where there a wind over tide situations
- preparing in position ready any drogues that may need to be deployed, getting them out of cockpit lockers in advance so that when deployed there is no risk of cockpit locker swamping
- plot position and if a survival situation is anticipated, report position and interiors to coastguard
- keeping a towel close by to charts in the cockpit to dry them
- making sure no gear can shift, come loose or roll around
- putting on heavy weather gear in advance
- make sure grab bag is accessible and secure but easy to release
- tape up exposed locker hatch seams with duct tape
- make sure anchor and deck gear is very secure
- hoist radar reflector on separate mast halyard
- get some snack food available and easy to hand along with water bottle
- check PLB is still working, spare batteries to internal dry pocket in jacket, safety knife attached to lifejacket along with light, whistle, spray hood, personal small flares,

Most of this I do as a matter of daily sailing checks but it never hurts to have a laminated checklist to run trough to give peace of mind does it. Of course,  if I have done my pre safety passage planning, then I am unlikely to be setting sail in the first ace. I guess this is the checklist for when things unexpectedly change whilst at sea.

Sticky had a similar checklist for what to do in fog.
- slowing down and getting a fix on the chart
- Reviewing the passage plan
- if possible, heading for shallow water and anchoring
- being aware that if heading for a GPS waypoint, others may be doing the same from the opposite direction
- keeping channel 16 on and listening to all communications
- hoisting radar reflector immediately
- flares and torches and whistles to hand
- stopping engine at regular intervals to listen

There was more useful advice but this gives the flavour. Sticky has a website
Go to www.sail-help.co.uk
Sticky's forms can be downloaded from www.pbo.co.uk

Steve

2 comments:

Bursledon Blogger said...

Low pressure 963mb the least of your worries will be an increase in tidal height of half a meter unless maybe you're holed up in a waterside pub

steve said...

thats true - its what happened on the surge of '52 in east anglia along with the confines of the english channel causing tidal heights to rise even further

steve