Rocks and Heuristic Traps

On our last cruise in company we went for a very pleasant sail across to Inchcolm Island, anchored in the bay had a pleasant lunch and then we set off for an informal stern chase up Mortimers deep and back to the harbour. We had a bit of a nerve wracking few minutes, when one of the fleet bumped to Medulse Rocks on a falling tide. Quick thinking and action on the part of her captain, meant nothing more than a bit of embarrassment. Looking back over my chart plot I also had gone over the Western end of the rocks. It’s been a big wake up call to me and feel it would be helpful to share this with others.

I have come back to sailing after 20 odd years flying paragliders and being up in the mountains walking and skiing – mostly offpiste and more recently on touring skis. As a paraglider pilot, I have in the past been a trainee instructor and club coach. Rocks and hillsides hurt plain and simple and it doesn’t take very much to cause a fatal or very serious accident. We always reckoned and taught that most accidents happen to either novice  Pilots in their first year after learning to fly (I know how to do this), after 3 years (I have lots of experience now and lets push the envelope) and after 9 or 10 years (been flying so long its instinctive), and usually happen on local hills after a long period of poor weather. Paragliding is a very selfish sport and once you are in the air nobody can give you assistance – you have to rely on your own skills, and if you get it wrong it hurts. After 20 years of flying, I know that I actually know and understand very little about clouds, air movements etc etc. With sailing I am at the 3 year point.

With sailing, you might be on your own, you will have others on board who may be more or less experienced, but never-the-less getting it wrong might not be so quickly fatal (as a paragliding or skiing accident) but the consequences can be very severe, not only to yourself, but others with you and especially to the bank account.

Over the winter I went on a very good ski touring and avalanche course at Glenmore Lodge – basically how to move across mountains on skis and not get avalanched. There has been a lot of study recently on “Heuristic Traps” and how people naturally make decisions. I am not going to repeat it all here – there is a two page article here by Alan Halewood of Glen More Lodge, but to be brief we all unconsciously rely on simple rules of thumb –  “Heuristics”  – to tackle complex decision making processes.

We absolutely fell into a “Heuristic Trap” on the last cruise in Company – a potential accident came out of nowhere. It’s a really thought provoking article and following of the key parts, analysing the wee bump on the rocks:

Familiarity – “There aren’t any rocks here” The Forth is familiar to most of us. I don’t think any of us looked at our charts on the day. We all know that there are Rocks on the North Side of Inchcolm. Instinctively I think the Forth lies East West – it doesn’t – its more North East / South West, and when I asked my crew to steer Northwards out of Inchcolm whilst I put the sails up, I was using instinct. The Medulse Rocks lie Due North of the Abbey.

Consistency / Commitment – “Let’s stick to the plan….” – or “Let’s get back to the pub” how often do we carry on regardless. We were rushing to catch up with other boats that were already sailing away, and to be back in time for the boatman.  The larger the group the more susceptible you are to such a trap. If we were on our own I would have checked the chart.

Acceptance – “Shes Nice” – a lot of avalanches happen to mixed groups. You want to be appear good in front of others. In sailing you often have friends, family or colleagues on board and you don’t want to appear the boring old fart constantly fiddling with the charts, taking a site or tweaking the sails or rigging a restraining line to prevent an accidental gybe. Don’t be afraid to accept the soft option or ask advice.

The Expert Halo – others in the mistaken belief that I have a clue, followed my lead. Leaders can get it wrong – and I did. When it comes to decisions add your opinion, and if there is a concern voice it.

Social Proof –  this is the sheep mentality and the acceptance that because everybody else is doing something it must be OK.  Just because you see lots of boats sailing between the Car Craig and Inchcolm don’t assume its safe – make your own decisions.

Scarcity – we have all been here – snowed under at work, weather has been foul for weeks, I have a day off and there is a window in the weather. There is another gale coming in, but haven’t been out for weeks and it’s the only opportunity I have for ages. The short window we had with the tides was definitely a factor – if we had spent five minutes studying the charts at the beginning of the day I wouldn’t be writing this email.

Take a moment to study the charts, take a moment to check the rigging and the boat, brief yourself and other well and don’t be afraid to ask.

And Rocks are useful – for barnacles, ballast and building with, but generally rocks and boats don’t mix very well so keep safe.

Patrick Angier
Cruising Secretary, RFYC

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