Crew Blog

Light airs downwind

30 April 2008

Glasgow: Scotland with style Clipper recieves a little help from their Chinese mascot

Here we are on Glasgow: Scotland with style Clipper on a beautiful hot sunny day with blue sky and hardly a cloud in sight sailing down along the Baja California in Mexico. I say hardly a cloud but the one cloud on our horizon is that we are meant to be racing and we do not have much wind, with even less forecast for the next few days. If there is one thing which a racing yacht need above anything else it is wind – and not the kind we often have on board from eating too many beans.

What wind we do have is coming from behind us, giving us downwind sailing under spinnaker. When you are sailing downwind the effective strength of the wind is reduced. The apparent wind which the yacht experiences is less than the true wind as a result of the yacht’s own boat-speed carrying it away from the wind. This effect is more pronounced the deeper the yacht sails downwind. Sailing downwind in light airs poses a special problem in that the yacht needs wind to power it, but what little wind there is becomes even further reduced by the yacht’s own speed. The key is not to try and sail deep downwind but rather to reach across the wind and use the increased apparent wind to generate boat-speed. Maintaining boat-speed and apparent wind becomes more important than simply trying to point straight at your destination. Therefore we sail higher and hotter angles than we would in stronger wind and gibing angles are increased. The extra distance sailed is compensated for by higher boat-speed. Apparent wind direction also changes much more rapidly with changes in the yacht’s heading than it would in stronger wind.

The effect of this on sail trim is to sail with the spinnaker pole set further forward and the spinnaker sheeted in more. In very light airs the mainsail may blanket the spinnaker and starve it of air so the mainsail is centred to allow better airflow over the spinnaker. Other tricks to improve light airs performance include replacing the heavyweight spinnaker sheet with lightweight ones and removing the barber haulers and lazy guys to reduce weight and drag on the spinnaker.

Downwind sailing in light winds can therefore be quite a difficult, technical and cerebral affair requiring high levels of concentration, which some sailors love but some hate. Luckily here on the Black Pearl we have a specialist light air downwind helmsman who joined as a legger in Qingdao and who always seems able to squeeze that extra tenth of a knot which has given us our reputation as being a quick and slippery boat in light winds.

Andrew Sheppard
Glasgow: Scotland with style Clipper aka The Black Pearl

1. Emma, 30 April 2008

Keeping everything crossed for you guy’s, in front again. Hoping you get your own personal windy patch propelling you all the way to Colon. LOL Emma

2. Andy Cole, Worcester 30 April 2008

Andrew, I knew this had to be your blog well before seeing your name at its end - a great explanation on light downwind sailing which I will expect to see appearing in the next version of the Clipper training manual!
Well, I’m sure there are many more secrets to setting the pace in this race that you haven’t passed on - keep up the concentration and maintain the competition with those other regular front-runners.
All the best
Andy

3. caroline, Brussels 30 April 2008

big kiss to my little brother - thanks
go go glasgow !!!

4. caroline Fitzpatrick, dornoch 30 April 2008

Well Black Pearl - you’re holding hands with the Yankees all the way - just make sure you get over the winning post just ahead - keep it up you love the light winds as you are all so good at changing tack - is that the right expression not being a sailor!! Best wishes Caroline Fitzpatrick

5. Bruce and Jackie Smith, Glasgow 30 April 2008

Please anchor immediately!
I am getting no work done because I am glued to the screen all day. Glasgow in the lead,
Glasgow overtaken by New York, only a mile in it, Glasgow and NY joint leaders but H & H better boat speed reported
If you show lights at night gradually reduce the voltage to your stern light very very slowly.
It doesn’t half drive ‘em daft astern of you!
In an effort to catch up they may do something too risky and POP! that’ s one less to worry about!

Have you any mines? One or two rolled off the transom perhaps?

You’re doing great. We’re all rooting for you and whistling for a good breeze just for you and windholes for the rest!!

6. Lynne Ingham, Lichfield, Staffordshire 30 April 2008

Hello Jeanette and fellow crew members!
Hope the sun is still shining and that the wind is doing exactly what you would like it to - last lot of April showers here!
Very impressed with your endeavours so far - sounds so exciting!
Will look forward to keeping up with your progress.
Take care!
Much love from Lynne, Peter, William & Olivia xxxx

7. Lorna & Jon, Barry, Vale of Glamorgan 30 April 2008

Well, that clears things up then! (sorry, motors not sails are our thing!) Half understood it but its the race viewer we go on and so far you and NY seem to be playing leap frog! Still a long way to go but fingers and a lot of other things crossed for the Black Pearl and a podium. Looks like its going to be another nail biting race but every faith in you all - carry on doing whatever in the light wind because it seems to be working but try to keep NY and the others behind you!
Sail very fast and safe as always,
Lorna & Jon.

8. Duncan McKeeve, Toronto Canada 01 May 2008

Keep it up Hanna and crew you are doing so well. The Black Pearl can be home first, come on “let her go lassie go”
Duncan in Canada

9. Sarah, Crowthorne 01 May 2008

Looking at the latest sched you’ve still got the BP’s nose out in front and successfully squeezing those extra knots - keep up the great sailing Glasgow!

10. Erica, Edinburgh 01 May 2008

A great blog Andrew, thank you. Your light airs downwind helmsman has an interesting look! Delighted to see you guys battling away at the front of the fleet again where you belong. The Black Pearl has deservedly built up an excellent lights airs reputation, and I know you have the focus and commitment to keep this up over the rest of this nail-biting race. Good luck!

11. Doddsy, Finally back at work in the weege! 01 May 2008

Mr Sheppard, it almost sounds like you know what your talking about, haha! You also brought back the “fondest” memories of the beans, aah the beans! Good to see freak toy is paying for its berth and making itself useful these days too.
Loving your work guys, keep it up and hopefully that yellow pennant will be flying from the inner forestay where it belongs! Finally came back to the UK on Sunday - man its cold here!!
Thinking of you all,
Doddsy

12. Diane Searls, Ireland 01 May 2008

Interesting techie info Andrew - a good insight into what you all have to think about constantly when we at home are thinking - light winds, little progress. Just one question - lately pictures have often featured the smaller, furrier members of the crew at the helm. Is this a tactical approach, for less wind drag than a large humanoid at the helm? If so, it seems to be working - up the teddies!

13. Gavin Sherriff, Essex 01 May 2008

A very detailed explanation of the intricacies of light-airs sailing. As the non-sailing Sherriff brother, I just wish I understood it! Whatever it is that you do to squeeze some extra speed out of The Black Pearl, I’m glad that you appear to be better at it than most of the other crews. Well done all, but particularly Colin. A good effort for an old man.

14. Roger & Chris Brunton, Bright's Grove Canada 01 May 2008

Robin
Happy Birthday to the OLD MAN of the sea
Happy 60th birthday!!! We have a cold bottle of bubbly on ice for you when you reach Canada
LOVE Roger & Chris arrrrgh…
happy sailing the Black Pearl

15. David Frame, Lenzie, Scotland 01 May 2008

Robin,
Hope I am not too late but the computer was down.....Happy 60 Birthday; remember 60 is the new 40. The delights of the free travel Scottish Government bus pass await you; at least you will be able to travel for free unlike the trip you are on. Could you finish the birthday celebrations of Tunnocks Caramel wafers and IrnBru and you and the rest of the crew get on with getting back into the lead. Take care now that you are slowing down due to age.
Go Black Pearl and regain the lead; all the best to Hanna and the crew.

16. Alice, Derbyshire england 01 May 2008

Robin Happy 60th birthday you are getting to be an old fart will soon have caught up with me. you take care.
Loads of love your big (older)cousin Alice
xxxx

17. joanna broughton, Stratford Upon Avon 01 May 2008

Hi Jeanette
Wow, go for it ‘not so Ancient Mariner’. Loved hearing your progress via gail and this wonderful website. I take my hat off to you for your focus and drive. Praying for the right amount of wind for you. Goodest luck, love jo

18. John Diffenthal, Sandhurst, Berkshire, UK 02 May 2008

I thought that you would all be missing the Times crossword, but it sounds as if you are being set teasing problems all day.

Sail safe and fast.

Go Glasgow!

19. Joe mac (Glasgow leg 4), Scotland-work ;-( 02 May 2008

You been reading them books again Andrew, it will be quantum physics next.
Dont give too much away you never know whos reading these blogs, we need all the advantage we can get.
Brilliant to hear from you at last, and the explanation on light wind sailing was fantastic, i now know where i was going wrong…
I think Liverpool will be taken over by Glasgow on the day for your arrival so ive book flights to meet you in Cork. More room to see you and more beer to go round.

sail safe and fast… 60 points up for grabs.

Joe

20. sian reynolds, Bristol - no where near Hawaii! 02 May 2008

Come on the Ninja Black Pearl! Great job guys- but having said that its the only way you guys know how to do it, with STYLE! Keep up the great work and you’ll soon be flying past H&H;& NY stealth style! Love to you all & hope the choc is not melting in the bildges!!! All my love & best wishes sent in the wind. Sian.x x x

21. Peter & Elspeth Eggleton, Sunningdale 02 May 2008

Great to have the opportunity of seeing the Lisa and some of team as well as the boat during their stay in Santa Cruz. We may need to read the down wind description again on a day that we’re not suffering from jet lag (not something you all have to contend with!) now that as Elspeth & I have arrived safely back in the UK. Keep up the good work and see you in Liverpool.

22. Alison Duffin, Belfast 02 May 2008

Glasgow you’re doing well, keep up the great work. It’s nail-biting as always but I’m following the race viewer religiously and cheering you on every day.

Keep it up, sail fast and go Glasgow goooooo!

Love Alison

23. jerome aucan, PBYC Hawaii 03 May 2008

It s heartwarming to see you girls and guys in first place. You ll always be first place for us !
Doddsy, it fits awesome, and maybe see you in London Sunday .

24. Andy Cole, Worcester 03 May 2008

Unbelievably close racing - I can’t imagine the pressure each time you go on watch...enjoy the fantastic sailing and keep on pushing hard with the leaders...looks like there will be many more twists and turns in this race!
All the best
Andy

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