Reddit mentions of The Lo-Tech Navigator

Funny, was thinking the same thing. I've thought a bit about this, hope the post is not too long.

There are many great examples of people who have become totally self sufficient on a good vessel.

Learning:

There are obviously thousands of books on sailing and a lot of good information. But having read quite a few and done a fair amount of ocean sailing, for these purposes, I would try and find books that ARE about:
Single handers (people operating vessels alone - whether or not you plan to be alone...there is always the chance that you will end up that way)
People who have managed to make it self sustaining
Sailors who equip and manage their vessel on a very strict budget
People who were amateurs that over years logged a lot of miles, and are offsetting their debt by publishing a how to. Lots of honest good stuff in here.

Also try learning what you can about Celestial Navigation, Dead reckoning, Weather, seasonal patterns, and global sailing seasons. A great resource for this is The Lo Tech Navigator. Not only does it explain the theory quite well, but also instructs on how you can actually build some critical sea nav pieces yourself. Depending on tech is good, but the failure rate on electronic devices is ultimately 100%. So knowing how to do it all old school...is well...we're all here so we get the value there. Knowing where you are, and what the seasons do in different areas is really a powerful tool to hedge your bets against adverse weather conditions. IMO, knowing how to batton the hatches, douse all sail in 20+ foot seas and deploying a sea anchor is the next best thing to having the best weather info and a super fast sailboat (in SHTF...unlikely and unsafe respectively).

Take up some basic sailing courses. Search in your area, there are almost always small sailing associations that you can join for a very small amount if anything and learn to sail at least small dhingys. It has been said by more than one person that these are the absolute best way to learn basic sailing theory as it puts your in a very tactile relationship with the forces at play.

Stay clear of books about:
Racing, COLREGS (so called rules of the road), older historical stuff, Any type of boating that is not basically a very heavy, sturdy monohull with a traditional (bermuda or junk) sail plans. While these are all very fun and useful, in a bug out...there not going to be a lot of use, because they are all basically recreational or of legal importance, and I think the USCG will have better things to do than to ticket you for failing to follow rules of the road.

The Boat:

My set up here would be, steel, monohull, full keel, dacron sails, junk rig, preferably between 38 and 45 feet. This covers the basic problems of extended voyages on a sailing vessel. A steel hull will give you better durability. Yes there are issues over a glass boat...but I would rather careen, sand and paint and just blow thru coral that you don't have charts for rather than get sunk. Monohulls...really hard to knock down, and are mostly self correcting in a capsize. While the catamaran in waterworld seemed nifty, if those get knocked over, which they can more easily...game over pretty much. Full keels are more solid in the water, smoother sailing and don't have fins that get stuck if in shallow waters...plus you can carefully careen them on low tides to to bottom repairs with a much reduced risk of damaging the hull...or fin keel. Dacron is the toughest and most durable for the price. Junk rigs while many people will rail against, are slower. But easier to sail alone, easier to reef in rough weather, self tackings, less stress on sail material and reduce rolling of the boat in heavy seas. The size is optimal for comfort, less roll in the swell, and sufficient size to increase speed as the result of a steel hull.

Load out:

Tons has been written on this and everyone has they bug out supply list in their own mind. All I will say is what my father is fond of saying "Keep it simple stupid". The more tech, the more systems you have, the more parts, more weight, more tools you need to have to operate it. I am very much of the opinion that some time spent learning the old school, and keeping the vessel ship shape is way more important than learning to depend on expensive tech which will fail you eventually. If you've read "Sailing around the world alone" a self steering wind vain is replaed by simply learning to ballance the sails and lashing the helm. Just one example. But if all you need is your boat, the required mechanical components (rigging, chain, anchors etc...extra of all of that is worth getting) sails, sheets, etc then you CAN get buy...as the poster mentioned, on 15th century (and way earlier) tech but with a sturdy seaworthy 20th century vessel.. You will be able to outlast all the retirees in factory mint hunters packed with GPS and radar.

Necessities:

Food gathering supplies (out of scope here). Water gathering supplies. A good rain water collecting system is good, and good holding capacities, and always be on the hunt for land based fresh water supplies. As much diesel as you can carry, and always be on the lookout for more.
For power, I am a fan of water impellers. Simple in design, always operating even if you are drifting, easy to repair...just be sure to really tie that sucker on hard. Anything else...vitamins, medicine, etc...obviously whatever you can get your hands on...bring it. I would pack the boat with this before worrying about spending cargo space with tools and parts for tech. Also, as good a set of paper charts and know how to navigate with them. These can be gotten fairly cheaply and in compendium style collections.


The bug out mentality:
The interesting thing about sailing for a bug out..is that you have to apply everything we are all trying to learn and assemble just by being readers of this subreddit. Even in a regular sailing voyage, the sea will test you, demand all of your respect and faculties, strength of body and mind. You need not be some tough as nails sailors...teens circumnavigate alone annually. But you will need to muster all of the know how, planning, smarts etc to stay alive. But since you got through this TL;DR mess, it means you are not afraid to scour for information to equip yourself against anything. And all of that learning will pay off equally as well in a sailing scenario as it would on land. You will always need to go ashore for various things...I cannot think of a single situation where people don't out of necessity. But armed with plans, information, maps, (everything you would want in a land based scenario) your passage times can be relatively short compared with your land falls to resupply, repair in uninhabited or non-hostile places. The south pacific is absolutely filled with such havens.

Sorry for the long response, but definitely fun to write about. Hope any of this is helpful if not in a bug out at least to the imagination.