Is it worth tacking upwind with a Flat Earth sail?

Flat Earth kayak sails will sail to about 68 degrees off the wind. This means they can definitely get to windward but is it worth tacking upwind or should you just drop the sail and paddle? To find out I did the following experiment and recorded the data on my Garmin GPS.

This GPS track shows tacking upwind into a 12kt WSW wind. Although I seemed to be sailing about 45 degrees off the wind, that was the effect of the apparent wind, the combination of true wind and the wind generated by boat speed. The GPS track shows that a Flat Earth sail will point about 68 degrees off the wind. This compares with about 45 degrees for a typical dinghy with a centre board. At first I tacked upwind while both paddling and sailing. I covered 1600m over the ground but only 600m upwind in 15.28mins. The over ground speed was 6.3km/hr but the upwind speed was only 2.4km.

Next I dropped the sail and paddled directly upwind. I covered the next 600m in 6.72mins, which meant the upwind speed was 5.4km/hr. The conclusion is that it is not worth tacking upwind with a Flat Earth sail. However, if you can lay, or nearly lay your mark, by sailing on one tack then it is definitely worth paddle sailing upwind with the Flat Earth sail. That is exactly what we did in the top photo, we were just able to lay Gull Point at the South end of Little Cumbrae on our way from Portencross to Glencallum Bay on Bute.

Alan Wilson is about to set off on his round Scotland trip.

Our good friend Alan Wilson is about to set off on his sea kayaking expedition round Scotland. He launches from East Tarbert, Mull of Galloway on Sunday 8th April 2012.

Alan is raising money for three charities, The Erbs Palsy Group, The Childrens Hand Surgery Education Fund and Microsurgical Reconstruction. You can visit his charity page here.

Good luck Alan and have a safe adventure. :o)

How's your roll?

 Just beyond the heavy industrial land of Hunterston...

 ...we were back on a wild stretch of coast. The Three Sisters of Hunterston were formed during the current Holocene period, when brash ice erosion rapidly cut the cliff line as the land rose at the end of the last ice age. Once the ice melted, the land continued to rise but the rate of erosion slowed leaving a rock platform at the base of the cliffs. Caves in the cliffs were inhabited as the area was populated following the retreat of the ice. The stunning Hunterston brooch was found here in 1830. It dates from about 700AD and is finely worked in gold and silver with amber decoration.

As we approached the end of our paddle, Colin and Andrew were somewhat overheated from keeping up with the kayak sailors.

As we approached Portencross Castle, Andrew asked me "How's your roll?" As I was looking forward to it with some relish, I said that it had bacon, lettuce and tomato with a thin spread of mayonnaise. Then, as Mike, Phil and I landed, Andrew and Colin cooled themselves with lots of rolling and thrashing about in the icy water. I watched them as I munched my roll and I realised that sea kayaking encompasses a very broad church of activity.

The shift in wind from SW to NW and our choice of launch site in the SE meant that we sailed the whole of this 30km circumnavigation of the Cumbraes. Yes, paddle sailing your sea kayak is a whole heap of fun, even though it might lead to excommunication!

Fast breeders at Hunterston.

On arrival at the Ayrshire coast we arrived at...

Hunterston nuclear power station. The water in these parts is like warm tea...

...due to the outflow from the reactor's cooling water. It is a particularly attractive spot for the local eider ducks. Quick as a flash, Phil quipped "radioactive whoo whoo birds!"

"Not so" I retorted, "those are fast breeder whoo whoo birds!"

Paddling like lions round the Cumbraes,

 We proceeded down the Largs Channel towards the giant cranes of the Hunterston ore terminal.

On the way, we passed the stone "lion" (a weathered basalt dyke) on the south end of the Great Cumbrae.

High above paragliders were enjoying the  uplift above the Fairlie Hills.

At sea level we were still able to sail across the Tan, which separates the two Cumbraes.

 Colin and Andrew carried on paddling hard keeping up with the kayak sailors. They paused only until a motor sailor decided on which way to turn.

Finally the Firth opened out and we set off across the shipping channel to the Ayrshire side.

The application of elbow grease to avoid a ferry glide.

 Refreshed by our stop we...

...continued up the west coast of Great Cumbrae island with Bute and Arran in the background.

 Mike and I swapped the Delphin and the Cetus MV and it was...

...not long until we rounded the north end of the island and entered  the Largs Channel which separates the east coast of Great Cumbrae from the town of Largs on the Ayrshire coast.

 We could now see all the way down the channel to the twin cranes of the Hunterston ore terminal.

The SW wind had now veered to the NW and we were able to continue sailing on the final leg of our circular course.

 However, we needed to apply a little elbow grease...

...to make sure we kept clear as MV Loch Shira (the Largs Cumbrae ferry) rapidly glided towards us.

Returning to sea after a refit.

By the time we got to the Great Cumbrae, the two newcomers to our little group, Andrew and Colin, were pretty tired, trying to keep up with the kayak sailors, it was time for a break. They are shortly to sit their BCU 3* with Bruce so we thought it would be good to give them some experience of open crossings. They had now completed 2 crossings of 7.5 and 7.2 km so they were feeling rather pleased.

We made landfall on the...

 ...delightful red sands of Fintry Bay...

...where we took second luncheon and whiled away a pleasant part of the day...

 ...watching the geese migrating to their summer breeding grounds near the Arctic Circle and watched...

the ships pass in the channel we had just crossed. This is HMS Atherstone (M38), a Royal Navy mine hunter. She was launched in 1986 and has just returned to sea after a major refit. It was now time for us to return to sea after our luncheon refit. We launched ourselves with a nip of 10 year old Jura.

MV Solitaire, the World's biggest pipe layer ship.

 From Glencallum Bay, we took off in fine style, sailing on a broad reach...

 ...past Little Cumbrae Island...

 ...with its Stephenson lighthouse.

 We were bound for the north end of Great Cumbrae...

 ...where a great ship was lying at anchor.

She is the MV Solitaire, the largest pipe laying vessel in the world. She was taking on a supply of pipes from tender vessels. She was built as a bulk carrier in Japan in 1972 but converted to a pipe layer in 1998 by Swan Hunter on the River Tyne. She is 300m by 40m with a gross tonnage of 127,435 tons. She can carry 22,000 tons of pipe and can lay 9km of undersea pipeline per day.

Leaving Glencallum Bay under sail.

 All too soon our sojourn at Glencallum Bay came to an end.

 The breeze picked up as soon...

 ...as we left the bay and...

 ...cleared the Rubh, an Eun lighthousen on...

...our way across the Firth of Cyle Channel to the Cumbraes.

Crossing the Firth of Clyde channel.

From Little Cumbrae island our course lay a few degrees further north. This allowed us to ease our sheets and pick up speed on our crossing of the Firth of Clyde channel.

 Andrew and Colin worked hard to keep up with the kayak sailors as we crossed...

 ...some rough water beneath the Little Cumbrae lighthouse as the ebb tide met the opposing SW wind.

 Slowly the wind increased as we crossed the channel...

... and entered the ebb stream off Garroch Head  but soon we passed...

 ...the light of Rubh' an Eun and entered the shelter of...

Glencallum Bay. Time for first luncheon.