Endurance limits

PhillM

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Ok so I am currently only marina sailing, usually only at weekends, but I do want to grow the cruising grounds over the next few years. I am expecting to be SH.

As I am now putting everything back after the refit, I got started thinking “how much of ...” I should or could I carry.

I’ve worked out that with an extra leisure battery and running the engine for 1.5 hours a day I could keep power topped up. Assuming 2L / hour diesel for the new Beta 14, tank of 25L + 2 x 10L jerry cans, I have over 15 days fuel so keeping about 1/3 spare I could go for 10 days and have all the power I need.

I think that I could live on about 5L fresh water a day. So far I have easily found space for about 50l –in the small tank and a variety of bottles sizes = 10 days’ supply. I guess I could probably find space for a few more bottles, so let’s say we get to 80L that would give me 10 days at sea and 2 days spare.

I can easily see how to store 15+ days of food. Keeping it fresh would be a challenge but there is no reason i coundt live on tins / packets etc.

So it looks like my endurance limit could well be 10 days at sea. Does that sound a reasonable supply to have on a 25’ MAB playing in the Solent and eventually along the channel (and perhaps across it)??
 
So it looks like my endurance limit could well be 10 days at sea. Does that sound a reasonable supply to have on a 25’ MAB playing in the Solent and eventually along the channel (and perhaps across it)??

Seems significantly higher than necessary to me!

Singlehanded around the Channel you shouldn't be out for longer than you can go without proper sleep - I'd suggest 36 hours as a maximum although I wouldn't stretch it that long myself. So this idea of many days' endurance at sea is not really relevant. The nearest you probably get is how long you can hang out in a lonely anchorage before having to fetch more fresh water. Even where you can't lay alongside a quay with a hose, lots of places have somewhere ashore you could fill up a jerrycan or two in the dinghy. Similarly, food endurance is just a question of how often you can be bothered to go shopping. I generally provision for a week, not dissimilar to a supermarket shop at home really, but generally assume I'll pick up some bread and milk etc on the way. If cruising France I might back off on the pre-stocked provisions a bit to allow for buying interesting local scran.

Personally I'd prefer solar panels to running the engine purely for charging (but if you're coastal around the Channel, you'll probably need to run it for navigation anyway) - but appreciate they may not be easy to fit on your boat.

Pete
 
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Coastal sailing along the South Coast you will not normally need to run your engine just to charge the batteries, and it will also not do your engine any good as it is not designed to run long periods under light load. However you will need to run your engine far more than you think. Not unusual to find a cruise log showing 30-50% of the time with engine being used for propulsion. Fit a solar panel to top up the battery. Your tank capacity is on the low side, but will give you about 15 hours running time plus your back up - but that is not unusual for a small boat like yours.

Water is never in short supply if you top up every time you are in a port. Unless you are using water for regular showers you do not need that amount per day. You can cook in salt water if you need, but using bottled water for tea and coffee and water tank for other uses is common.

Expect you will learn to adjust your way of cruising to match the resources you have and doubt that being away from land based facilities for 10 days at a time is a desirable way of coastal cruising!
 
If you are running your engine just to charge the batteries then you will use a small fraction of 2l/hr. If you are using an electronic tiller pilot whilst sailing you will probably need more than 1.5 hours a day, even with smart charging from alternator. At cruising revs and propelling in gear you will be looking at more like 1 or 1.2l/hr.

Water - if you take other drink with you, eg apple juice, energy drinks, and 'wash' using wet wipes then it is surprising how little water you need.

If you look at the Jester forum you can get an idea of the endurance that small yachts are capable of if you put your mind to it.
 
If you look at the Jester forum you can get an idea of the endurance that small yachts are capable of if you put your mind to it.

I'd love to be able to do the Jester. When I was a kid I wanted to sail round the world on the whitbread. Nowadays, I will celebrate when I make it round the island.

But yes, am in awe of what those guys can do in a small boat.

Thanks for the fuel tip. I'm not sure where I got the 5L of water a day from. Distant memory of one of the guys on here who did that mini transat but it sounds like I got it wrong.
 
I find that when I need to use the engine it's because there's no wind and my beta 16 uses about 1.5l p/h at 2000rpm which will push me through calm seas at 4.5 - 5 kts. I sail whenever I can using a spinnaker and light airs genoa to keep me making headway but utimately 30% or more is spent under engine. Similar to you I have a 30l tank and 2x10 reserve cans but I always work on leaving minimum 5l in the tank so the pickup tube doesn't suck air and always leave 5l in one container for emergencies so giving 40l of range (I work on 24 engine hours of range) but the wind usually picks up in 24h at some point.

If your canny with things like washing up and bathing you can use a lot less than 5l water per day. It'll probably disgust some to learn that you can do a flannel bath, wash your hair and clean your teeth in less than .5l of water.

Endurance wise, I find 150nm is the kind of the absolute max from one safe haven to the next. That works out about 36 hours and is seriously knackering even in calm conditions. 24 hours is tiring enough for me now. I have hove-to and done 10 minute cat naps on occasions but only when I'm really tired and when I'm well out of any sort of hazards (shipping, land, weather, fishing boats, tides etc -you need to work out your own rules on that one as strictly speaking you are not keeping a proper watch).

Electrickery is a problem (especially as my LED masthead is out at the mo) and find that if I run nav lights (3.3amp), autohelm (1.5amp), instruments (1 amp), vhf (unknown) and some interior lighting my battery (100ah) is running low after an all nighter. I have a 40watt solar panel but this will not charge the battery up so I usually motor for an hour at least before arriving at an anchorage to have some charge in the battery for domestics. If I had more money I would get a another solar panel and a wind gen and then I think I could be almost self sufficient in power. I have a second, smaller, battery kept strictly for engine starting if the other one is flat. The real problem is when (like this last week) you get stuck somewhere because of bad weather. Water, electricity, fuel and food all become a problem if you don't know how long you will be stuck there.

Food is up to you, I spent four days living off porridge and instant noodles which is cheap, warming and ultimately very boring.
 
I should add that I am not planning to be sailing for 10 days, but I could see me anchoring or picking up a moorning for a couple of days and not wanting to lug lots of food, water and fuel around in a dinghy.
 
PhillM,

I have just finished re-reading ' Very Willing Griffin ', the story of David Blagden taking a Hunter 19 across in the 1972 OSTAR.

He was on minimal supplies and had 2 pints of water a day, which I'd think on the insufficient side !

Dehyration is horrible and subtley creeps up on one slowly, making one feel ghastly and performing badly withthout one catching on; if this is down to seasickness, ' Dioralyte ' sachets are a great help, about £4.00 for 4 sachets from pharmacists, I reckon a very worthile part of any boats' first aid kit.

Another thing David Blagden had was a ( partly succesful ) solar still, but for sailing in the Solent / cross Channel I'd strongly recommend a large bottle of mineral water, I've had serious stomach upsets from the water at certain Chanell Island ports and seaweed in the boat tank but hopefully things there are much better now.

Have Fun,



Andy
 
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For me 3 or 4 days is enough then the draw of warm shower is enough to get me to a marina...

If your within range of marina's there is no shame dropping in on one once in a whilst to top up and clean up...
 
Perhaps working to 'endurance limits' is a flawed concept.

It is important to have enough decent water to drink in one form or another. That's not difficult to achieve. Then it's important to have enough 'other stuff' to drink when the mood suggests, whether beer, cider, wine or single malt.... That's not difficult to achieve. A couple of long-life carrier bags of stuff to eat....

One is never very far from a mini-supermarket, and there's no harm in anchoring v. securely, going ashore, and walking to the adjacent village shop. Fresh bread, some milk, and a local newspaper for laffs is good cruising stuff.

As for the frequent warm showers, there speaks a Solent dilettante...! :rolleyes:
 
For me 3 or 4 days is enough then the draw of warm shower is enough to get me to a marina...

I've done my share of bucket washes in the cockpit (actually I rather enjoy it if the weather's nice and noone's around) but there are often showers available even outwith a marina. Most West Country ports for instance have either a sailing club that's happy to make a few quid from coin-in-the-slot meters, or a harbour master's office with facilities. Itchenor's an example closer to home, and I hear there are showers at the Folly though I've never used them.

Nothing like Greece fifteen years ago though (dunno if it's still the same now). Lots of little old ladies up in the town somewhere, looking out for Brits with towels under their arms and renting out their bathrooms for a few drachma!

Pete
 
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