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Night Sail across Lyme Bay: Swanage to Dartmouth

After a few weeks in the Poole/ Studland area it was time to push west a bit, which meant once again crossing Lyme Bay. Last year was our first time doing this particular crossing and with hardly any wind we ended up motoring the whole way for 12 hours! You can read our blog on that crossing here. This year we were taking it up a notch by opting for a night sail across!

As many of you know the Lyme Bay crossing can be a challenge if you get your weather and tides wrong, and the races at Peveril, St Albans Head and Portland Bill need to be navigated with caution. But with careful planning it’s no different to most sails and in fact once you get past Portland Bill it’s actually a long old (and relatively boring) slog across the bay!

We had stopped for a short stay at Poole Quay Boat Haven (only £7.50 for 4 hours!) to top up our water tanks and carry out a spot of food shopping. Catching the last of the ebb tide out of the harbour we motored sailed past Old Harry Rocks to Swanage Bay, where we dropped the hook in the northern corner for a few hours to wait for our later departure.

Swanage is a place dear to our hearts but this bay always seems to be rolly! And despite being sheltered by the wind we were still subjected to an uncomfortable swell for a few hours as we waited.

Yacht anchored in Swanage Bay by Ballard Down.

However conditions for our crossing were looking good; a 10-16 knot breeze from the north, an overnight temperature of 10°C and a wave height of just 0.2m, with the tide set to turn at Portland Bill to a westerly direction at around 21.30.

We plotted our waypoints as follows:

WP1 – 50°36.323N 001°54.848W Close to Peveril Point
WP2 – 50°30.862N 001°59.282W Approaching St Albans
WP3 – 50°27.973N 002°20.000W Approaching Portland Bill
WP4 – 50°23.500N 003°00.000W Roughly halfway across the bay
WP5 – 50°20.007N 003°29.977W Approaching East Blackstone
WP6 – 50°19.792N 003°32.977W Entrance to Dartmouth

Sunset was at 20.52, sunrise at 05.19.

We decided on a departure time of 20.30. Although this meant we would be against the last of the flood tide up through the channel, we figured that it allowed us enough daylight hours to navigate out through the many pots that litter Swanage Bay and down the coast to St Albans Head!

The Actual Passage

Well we got bored waiting so weighed anchor at 19.45, 45 minutes ahead of schedule 🤣 The wind was very light, just 1-2 knots, not the predicted 7-10 which was forecasted for this time. We raised the main to the 2nd reef, well under for the predicted wind of 10-16 knots but our main sail is very powerful and we would rather feel comfortable and overly cautious at night than over powered.

Sunset Hour – 20.35
Civil Twilight – 21.21

21.45 – 50°30.677N 002°05.373W – We attempted to sail for a short bit but the wind just wasn’t strong enough to keep the sails filled, plus we still seemed to be against the tide. The tidal stream atlas showed the tide in the channel ebbing at 21.59 so we must have been close to the turn of the tide, it just seemed to be taking its time! Over to shore we noticed a stack of falling lights in the sky. Peering through the binoculars we realised it was the firing range near Lulworth who were carrying out a night exercise. These must have been flares of some sort to simulate night fire, unfortunately impossible to capture on camera from our distance but pretty impressive to see.

23.40 – 50°26.959N 002°26.043W – We were approaching South of the Bill, the tide was fully in our favour and the wind was starting to increase – finally! With a speed overground of 8.9 knots we were flying along, albeit still with the motor running.

Nautical Twilight – 22.11
Astronomical Twilight – 22.37

Midnight – Finally the engine goes off and we’re sailing out into the darkness of Lyme Bay. Despite the lack of visibility it feels more reassuring having the engine off; less chance of getting snagged on a pot. Plus the quietness is almost meditative; the sound of the waves gently slapping at the hull is rather soothing. One of us takes the opportunity to get a spot of shut eye whilst the other maintains watch.

01.50 – 50°24.457N 002°48.062W – We head up a degree from our initial course of 260° to avoid 3-4 fishing trawlers that were circling in front of us. The wind was very light at just 7 knots from the north but we were still sailing along comfortably at 5.7 knots.

03.15 – 50°23.448N 002°58.310W – Wind still hasn’t got to the forecasted 10-16, it’s fluttering around 7-8 knots but still she sails on. Our speed over ground has dropped a little to 4.1 knots but it’s all good.

04.45 – 50°22.242N 003°06.182W – Damm it!….the wind drops off totally, our speed over ground drops to 1.5 knots and the sails begin to flap. Engine goes back on. But we take the calm opportunity to stick a couple of sausages on the hob and cook up some tasty breakfast baps in time to watch the sunrise!

Sunrise in Lyme Bay

And just 45 minutes later the wind returns and we’re back to sailing! One of us heads back to bed for an hour whilst the other enjoys the morning sail.

07.30 – 50°19.924N 003°27.730W – The wind is around a constant 10 knots but we’re now against about a knot of tide as we make our final approach towards Dartmouth. Despite the tide we’re still sailing along nicely at 4.7 knots.

Arriving into Dartmouth
Le Bellot Cruise Ship

08.30 – We slowly edge our way through the harbour entrance. We’re against the tide but it doesn’t feel particularly strong and traffic is very light. Moored up in the harbour is Le Bellot, a Ponant cruise ship, which we had seen on AIS earlier that morning. At 9.00am we come alongside at the walk ashore visitor pontoon in Dartmouth feeling happy and exhausted! However we still had the energy (and surprisingly the hunger again!) to have another spot of breakfast before heading to bed for a few hours.

We hope our account of our night sail across lyme bay is of help but please remember to plan your own passage with care. Each sail is different with different sea states and weather so prepare accordingly. This is for guidance only.


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