Fear in the Bay of Plenty

By Rob

The Scene

The build up of tension (read weather forecast) that sailors all know and fear the most. Wind forecast to die to nothing..... for many days...... seriously !!!. 

Just before the start, Sally on the foredeck

In the best long term interest of our campaign be both decided to up the "resistance training level" by starting the race as tired and work stressed as possible. Sleep would be a low priority for the next 3 days, grunt up !

I don't like light air and truly many of my really bad memories of this are in the B.O.P. When there is always a left over swell that rolls the boat uncontrollably and makes the sails crash in the rigging and just tear my heart out. It was this fear that consumed my mind until we finished that any moment the breeze may die. But while the wind came and went throughout the race we never lost steerage way, so again like so often the worrying was just a wasted emotion.

 The Race 

Another awesome start by Rob! (Photo Alison Howitt / comment Sally)

In fact on average there was more wind than predicted with interesting (funnelling) acceleration thru Colville Channel well above the forecast and lots of wind (gusting 30) around White Island. These  last 10 miles into White Island were on the wind, we   rounded about  23:00 on a very dark Friday night  . We know its not safe to rely absolutely on gps in close quarters but they are great tools to be used in conjunction with all other available sensors. So with a close eye on Hdop position errors, (a significant function on our Expedition performance software) cross referenced with depths and my eyes wide open we skirted White Island as close as I dared.  Things (like rocks) look closer to me at night. That was the highlight of the race for me, which is probably as it should be.

So the breeze came and went as we sailed back to Auckland. Luckily we held more wind than we expected and had a great sail in from Coromandel until Waiheke when it got really tough and we worked it as hard as we could for 6 hours until we literally drifted across the finish line on an incoming tide at 08:30.

What a relief. 2 1/2 days for 320nm? worse things happen at sea !

And we are off - 300nm to go!

Things that worked well:

Sally's handmade beanbag mattress, so comfortable and surprisingly warm, a must have

The Icom HF (long range) radio. I just love the fact that an electronic thing has lasted 12 years and still works perfectly.

Expedition performance software. When you are so tired you just cant think anymore but you need to know whatever, its right there, like a perfect navigator. Thanks Nick

Finished – 3rd on PHRF, 6th on Line

 

“Far better it is to dare mighty things, to win glorious triumphs even though checkered by failure, than to rank with those poor spirits who neither enjoy nor suffer much because they live in the gray twilight that knows neither victory nor defeat.”
Theodore Roosevelt (1858 - 1919)

 

First, sorry for the lack of communications. I damaged our modem at some stage and spent a lot of time thinking the problem was the new aerial, but it was actually the SIM card.

We finished yesterday morning at 8:39 am, 6th mono hull, just over an hour behind the Davidson 42 Mr Roosevelt. For me this was one to the toughest races I have sailed in mentally for a long time, I was certainly challenged to say the least. However, the best thing is that we went and raced and finished.

A full report to follow.

Thanks to Alison, Jenny and Jackie for watching the start and taking photos.

White Island starts 7pm tonight

Quick note, I am running late. The White Island Race starts tonight 7pm at Orakei. You should be able to see our AIS track until at least midnight. Check our updates on this site, or look at http://www.rayc.org.nz/ for our position reports at 06:40 and 18:40 daily.

Speak to you soon

Sea Breezes

Thou the sound of “light sea breezes” sounds rather nice to me, when cruising or staying at the beach cottage, it is a term that slightly concerns me with a 300nm race to be completed.

As we all know a sea breeze is in very common terms the breeze caused by the difference in temperature when the land and adjacent sea is heated. The land (in a theoretical world) will heat quicker than the sea. Once heated the land heats the air in contact with it, which will rise and be replaced by air which rushes in from offshore. The reverse will happen at night, the sea does not cool rapidly due to the specific heat capacity of water (think tomatoes in your toasted sandwich) as the land. Air then flows from the land to the sea.

Source: Adapted from graphic by National Oceanic Atmospheric Administration, Jet Stream.

The above description is very much sea breeze 101. In the real/non-physics world, the sea/land breeze circulations are affected by a number of other meteorological parameters including: 

• Soil moisture, increased soil moisture has been associated by decreased sea breeze frequency and strength.
• Sea surface temperature, lower sea surface temperature creates a larger temperature differential and therefore stronger sea breezes.
• Overall stability of the lower atmosphere. Very strong subsidence under high pressure can prevent air from rising, thus preventing the formation of cells. 
• Land topography, the greater the elevation, the cooler it is, so  less heating that occurs.

The Auckland/Hauraki Gulf sea breeze has been well described by various researchers , however it is a somewhat of a difficult  due to  local breezes from three different harbours interacting to form the final wind field.

Sea breezes in the Hauraki Gulf area are generally found in the summer and early autumn months with fine days and weak synoptic flows.  Their occurrence is correlated to the Southern Oscillation Index (SOI), an index used to quantify the El Niño/La Niña circulations of the Pacific Ocean. In periods of SOI close to zero sea breezes develop up to one day in five in October-December and March-May and once every three days in January-February. In periods of larger SOI the frequency is less due to the increase in synoptic wind, however sea breeze development has been observed one day in seven between October-May during such periods

In the absence of a geostrophic wind, immature sea breezes or ‘bay breezes’ tend to develop in the mornings reaching speeds of 5-8 knots by 11 am. These bay breezes are small areas of wind that move onshore in a variety of directions from ‘bays’ to the nearest land. The directions of the Auckland bay breezes are shown below.

Map showing elementary development of sea breeze in the absence of synoptic flow - source Mc Gill (1987)

In the early afternoon the bay breezes may mature in a true sea breeze with peaks wind speeds of between 15 to 26 knots. The direction of the wind of the mature breeze is dependent on the synoptic situation. If there is no geostrophic wind present at the time of sea breeze development, a convergence zone forms in the middle of the Auckland Isthmus and a small heat low develops in the south Auckland area as shown below.

Map showing mature of sea breeze in the absence of synoptic flow – source Mc Gill(1987)

If the prevailing wind is from the southwest the convergence zone is formed in a similar area to the no wind situation and then pushed east, and a large heat low forms over the central North Island thereby leading to large variations in wind speed and direction as the sea breeze develops as shown below.

Map showing mature sea breeze in south west flow – source Mc Gill (1987)

In north east flow conditions the sea breeze convergence zone is displaced towards the west as shown below.

Map showing mature sea breeze in north easterly flow – source Mc Gill (1987)

More tomorrow….

Mc Gill A.J (1987) “Sea breeze circulations about Auckland”:New Zealand Meteorological Service, Scientific Report 29, New Zealand Meteorological Service

White Island

The Round White Island race starts on Thursday next week, 7pm. So after a day at work, and a 3 hour motor down, we are off, through the Gulf, passing Channel and Cuvier Islands before the 90nm each way leg to White Island.

We have been very busy of late with safety equipment, Rob is preparing a posting on it at the moment. However without revealing too much, I can say that we are both feeling increased confidence from testing several our emergency systems, including steering with a drogue, man over board drills and a revisit of sailing with our storm sails.

Tactically, the White Island race, could possible require all my knowledge of coastal meteorology. The Bay of Plenty is well known for it’s sea breeze, however the “sea breeze season” is only starting. Over the last few days I have watched the predictions from various models and also the observations for the Bay of Plenty. The sea breeze development is still weak and is not extending far offshore. This could mean decisions between increasing the distance we sail to ensure we can take advantage of the sea breeze, or staying on the direct line between White Island and Cuvier Island, hoping that shortest distance will be quickest.

More time downstairs at the PC for me I can see!

Sea and bike survival

This weekend Rob renewed his Advanced Sea Survival. The two day course is focussed on practical skills for survival at sea.

I went to Rotorua and competed in the Bike the Lake cycle race. No podium finish, or even place  in the top few hundreds, but I did make it without getting a puncture this time.

 

    

My Riding Buddies – Neil, Jenny and Alison at the finish.

More on HF – SSB - Antennas

Carrying on from my previous blog on engineers antennas HF and SSB, in this second part I will more fully describe our emergency antenna setup.

 

I draw your attention to a very useful set of resources available free on the internet:

1. Field Antenna Handbook - US Marine Corps
2. Radio Operators Handbook - US Marine Corps

In the previous post I worked out the length of antenna for a given frequency that would provide the best chance of effective communication.  This certainly does not mean for a given frequency if the length is different you can not communicate, it just means that there is more chance at the lengths specified.

So how is it all going to work on the boat.

Situation one – the antenna is broken, but the tuner is intact.

Cut a new antenna from a piece of wire of a length greater than 7m as specified for our ICOM tuner. 

One end of the antenna would need to be lifted towards the sky, if the mast or part of it is still standing the wire could be hoisted on it, otherwise some other pole, like the prod, kite pole or boom could be used. The resulting antenna would have the characteristics of this sloping wire antenna show below:

 

Sloping Wire – source: US Marine Corps (1991) “Field Antenna Handbook” pg 4-34

Situation two – the antenna is broken, the tuner is broken

This is the situation where  having the antenna length appropriate for the frequency you want to transmit of is important. Normally the tuner, tunes between length suitable for the frequency and the actual antenna length using a series of capacitors and inductors. Without a tuner each time you change frequency, to optimise the chance of being able to communicate the length of the antenna must be changed.

The length of antennas required for international emergency frequency range between 32.6m for 2182 Hz to 11.6m for 6125Hz.

32.6m is greater than distance between the back of Coppelia and the mast head. Therefore the sloping wire arrangement used above can not be used. Moreover, it is likely that if we have broken the tuner, we might have suffered damage to the mast, and therefore we would not even be able to make a 11.6m sloping antenna.

The answer is a different sort of antenna, a vertical half rhombic antenna.

Vertical half rhombic antenna – source: US Marine Corps (1991) “Field Antenna Handbook” pg 4-37

The plan onboard would be to make some sort of pole in the middle of the boat. A shielded cable would then be run from the radio to the back of the boat, and a second wire from the ground plate to the same location. A piece  of wire equal to the length of antenna required for the frequency to be used would then be attached to these wires, and hoisted aloft in the middle, then fastened at the bow. The resulting antenna setup would form a vertical half rhombic antenna.

Ambition and Frustration

Today I was reading “psychology today”,  and came across an article on ambition and frustration, something that Rob and I both struggle with at times. We both have boat loads of ambition and become frustrated at how many things come in the way of our goals.

I found the below paragraph truly motivating and would like to share it with you…

 

The trick is to selectively give up specific battles, rather than to globally capitulate. Helplessness tends to be global. But maintaining determination while accepting temporary setbacks positions us well for future success.

Helplessness allows us to shun responsibility for the choices we make and the frustrations we encounter. We blame circumstances, fate, or other people, giving ourselves excuses for copping out. But nowhere is it written that everything must be easy or that others are the cause of our difficulties. Refusing to capitulate to helplessness allows us to accomplish the enduring goals we have for ourselves—and we mobilize the positive energy known as ambition.

 

check out the full article http://www.psychologytoday.com/articles/200804/neanderthink-the-ups-and-downs-ambition