A basic checklist for your next ocean passage

I have now done quite a few open ocean passages, and I start to be picky which boat and crew I want to sail with. A well prepared boat and crew is not a guarantee for a pleasant and safe passage, but surely a good starting point.

This is the checklist I made for myself, and -though not complete- might also be a base to start from, for any skipper planning an ocean passage, specifically if this is his/her first crossing.

The list starts with stuff related to the boat itself:

Rig inspection

Have a certified rigger do a thorough standing rigging inspection: condition of the stays, chainplates, spreaders, and all connections. Check the condition of the mast. Check all running rigging for chafing. Have a spare halyard and sheet.

Sail plan

Many ocean passages are done downwind. What is the sail plan? While it is perfectly possible to cross the Atlantic East-West with a small 100% self-tacking genoa, it might not make for a fast and comfortable crossing.
I'd rather look for a 120+% genoa, preferably with a whisker pole to pole out the genoa: downwind waves will push the boat left-right, deflating and inflating the genoa several times per minute, which will wear out the genoa, and put a lot of stress on the rigging.
Find ways to keep that genoa open. If no whisker pole, possibly find a way to sheet your genoa aft (through spinnaker tackles?), and use a barber hauler to keep pressure on the genoa sheet and trim it better.
Of course it would be nice to have a light downwind sail: a symmetrical or asymmetrical spinnaker (gennaker), or a kite (like a Parasailor), to be used in lighter (<20 kts) winds.
Have a good preventer system for your boom, connected to the end of the boom and onto your deck, preferably onto a cleat. Crash-gybing your mainsail can be a cause of major, if not catastrophic, damage. On several boats we did a crossing with, we always had both starboard and port preventers on, not only to prevent crash gybing but also to avoid excessive deflating/re-inflating of the main sail. The stiffer your mainsail (e.g. with batons), the more likely your mainsail will deflate/re-inflate rather violently, wearing out the sail and cars - and putting pressure on your mast, goose neck and rigging.

Chafing

On an ocean passage, anything which rubs against anything, will cause wear-and-tear or chafing. Even while, for instance, there might not be any tension or pressure between a sheet rubbing over your rail, after 2 weeks of ocean passage's "rubbing", for sure, there will be chafing damage.
Anything flapping (like a loose bit of sail cover) for weeks on end, will get damaged or worn. The foot of your genoa, at the luff e.g., rubbing over your bow's rail, will cause wear and tear.
My advice is to bring along some cheap and real thick plastic water hoses. Any running rigging rubbing against something else? Cut a piece off the hose, splice it, and clamp it over those bits rubbing. It will limit your wear and tear.
One note -though not part of the preparation but as part of your actual ocean crossing-: Twice so far, in a transat, we chaved through our spinnaker halyard, at the top of our mast (see picture). We learned to, every day, tighten or loosen up the spinnaker halyard a bit, changing the point where the halyard is "frictioning" at the top of the mast. A halyard chafing through (with a bang), with your beautiful spinnaker graciously falling into the sea and wrapping itself around your keel and rudder, can cause a major disaster or at least have you loose/damage your spinnaker.

Autopilot

Bless those who sail an ocean passage by hand-steering, but "most of us" use an auto-pilot, which, if well tuned, will steer far better and longer than a human. When is the last time, your autopilot was inspected? Do we have spare pieces for the autopilot, or a backup? I have never sailed with a wind-vane autopilot before, but that looks like a good alternative or backup to an electric autopilot.

Electricity - power management

Talking about "autopilots": if your autopilot is electrical (and not a mechanical wind-vane), your "Bob" (as we used to call our autopilot), will be the main source of electricity consumption.
Add to that the consumption of pumps, radar, communications (Starlink! - see further), navigation and charging devices, watermaker... and it is highly likely that whatever battery charging solar panels, wind generator and hydro-chargers you have to charge your batteries when doing day-cruising, will not be able to keep up with the demand for electricity on an ocean passage.
Wind generators are not very efficient when sailing downwind. The efficiency of hydrovanes is questionable - and sooo many buddy boats we sailed with on ocean passages had structural issues with hydro-generators which get hammered by the ocean waves.
The efficiency of your solar panels might be limited in hazy/cloudy conditions, if not shaded from the sun by your mainsail/rigging.
Choice is yours how you want to top off your house batteries: do you have a built-in generator aboard? Will you charge from the alternator on the main engine (maybe not a good idea if you have a turbo-charged engine, as charging batteries is typically done on lower RPM without engaging the turbo).
On several boats we sailed across oceans we had a small 0.9-1 KVA standalone generator we used to charge the batteries at night. A cheap and effective solution.
Oh, and those two 5-year-old 120 Ah lead-acid house batteries you used -up to now- for day cruising, might not be enough to hold the charge or keep up with the power consumption for too long.

Water

Sure you can cross an ocean using the capacity of your normal water tank and some spare jerrycans. It will demand strict water-usage "rules", though. Better if you have a water-maker, and better still if it is built-in, in the boat, with its saltwater in-take through a built-in seacock. A "portable" watermaker, with an intake via a floating tube, did not work well in our previous passage: we never found a way to ensure the intake tube stayed well under water. The intake sucked air bubbles (might have been cavitation bubbles), which can damage the membranes, and made any "water making session", a labour-intense and tiring venture.

Emergency and safety equipment

I do insist on a (properly registered and serviced) EPIRB (satellite emergency beacon), serviced life raft, "throw overboard" MOB buoys/lines fixed to the boat. Properly serviced quality self-inflating life jackets (PFD's) are a must (standard "rule" on past crossings was: PFD's on, from sunset to sunrise and any winds above 20 knots). Preferably PFDs are to be fitted with MOB (VHF-AIS auto-deployed location device) and proper tether lines (Oh, I had long discussions with the ARC safety crew, whether 2-point or 3-point tether lines are better. I stick to 2-point tether lines). I like crew to wear PLB's (Personal Locator Beacons) at night - these are small personal EPIRB devices, allowing to send a satellite distress signal to a coastal rescue station, when overboard and out of VHF/AIS range.
((And yes, rules #1, #2 and #3 on a boat are all the same: "DO NOT fall overboard"))

Navigation equipment

While you can cross an ocean single-handed on a raft with a paper chart and without any auxiliary equipment, I do prefer, on any yacht I sail on for thousands of miles, to have a good chart plotter system - preferably also with a screen at the helm position - with an AIS - Automated Identification System - receiver/transmitter connected to it. Hardly any boat sails across oceans, these days, without AIS.
And a radar, even if only run e.g. once per hour (to save power), can make a passage more safe at night. Not all boats (referring to those &&%%$$!! many small Chinese fishing boats we crossed paths with in our last transat...) transmit an IAS signal, AND a radar will help you to spot rain squalls building up behind you, allowing you to dose your spinnaker in time, or change course to avoid the squall.

Long-range comms

Being a radio-amateur ("ham"), I love HF radio, but long gone are its days as the main long-range comms system on a yacht. "Starlink", is the new norm now: affordable and reliable. And useful for safety, social communications, and downloading weather routing etc... When, last year, our fellow ARC+ boat "Hilma" lost their mast 3 days out of Cape Verdes, one hour after their distress Whatsapp message to the group chat via Starlink, three other ARC+ boats were standing by her for assistance. Do I need to say more? And beyond: my family and friends loved my daily updates during our crossing, via pictures, videos, microblogs, and progress plots.
Beyond Starlink, as a contingency, a small portable satcom device (Garmin Inreach or Iridium Go), is advisable. Not cheap though, comparing their bandwidth/functionality with Starlink, but a good fallback. And -God forgive- something you can take with you in a life raft.

Insurance

There is a more-than-a-fair chance your Med cruising insurance e.g. will not be valid for an ocean crossing. What insurance do you have for the crossing? Insurance fees are notoriously high for ocean crossings, but so are the fees to rescue your yacht and/or crew in case something goes wrong. See also the ARC-chapter.

And now moving onto more "non-boat" topics.

To ARC or not to ARC.

Every year about 100 boats cross the Atlantic in the ARC+ flotilla from Las Palmas to Grenada with a stopover in the Cape Verdes (Mindelo). 200 more boats cross from Las Palmas to Rodney Bay Marina in Saint Lucia about a week later.
I did two transat crossings with the ARC/ARC+ and two crossing "by ourselves".
Participating in the ARC/ARC+ is not cheap. But it has its clear advantages: It is nice to cross the ocean as part of a like-minded group of fellow sailors and the ARC organizers are great in creating that social environment to meet up with fellow ocean crossers. AND the ARC crew create a whole safety/experience-based environment to "chaperonne/mentor" participants into a safe passage.
Once the fleet assembles in Las Palmas, they do safety inspections, run a ton of seminars on topics ranging from "ocean fishing" to "weather routing" or "downwind sailing", organize social events, day-care for the kids (so their parents can prepare their boat), facilitate customs and other administration, help with booking your berth in the marinas, etc..
During the actual passage, they are super-efficient and professional in providing assistance in case of emergencies or incidents. All-in-all VERY well run, and my utmost respect goes to the ARC/ARC+ "yellow shirts"!
When we did not cross as part of the ARC, we kinda created our own social network of buddy boats who we picked up sailing months prior in the Med or in preparing the crossing, and we kinda created a virtual buddy-boats' flotilla, with many parties held in our "assembly points" of Gibraltar, Gracioso, Las Palmas and Mindelo. But it is up to you to engage and/or to organize.
Beyond the main transat E-W passage, the ARC also organizes group W-E transat crossings, the "yearly migration" from the UK to Las Palmas, and the "World ARC" - a global crossing. One thing to check out, though is: Many insurance companies give a significant premium discount when you are part of the ARC (or ARC+), as the ARC rules and inspections are rigorous. In our past crossing, our skipper said that his crossing's insurance premium discount, as an ARC+ participant, was bigger than the actual fee he paid for his ARC+ participation. Keep in mind, though, that in order to pass the ARC/ARC+ safety inspection, you might have to buy/install some extra stuff (and spares) which you had not planned for, thus incurring extra costs (also for the sake of extra safety of course).

Food... ah.. Food...

I hope your yacht has a fridge. A freezer is a great "plus": Frozen pre-prepped meals for those "difficult" days, are heaven-sent when the boat is rolling left-right so heavily, it is hell even just to cut those ever-rolling and escaping veggies, leave alone to stand on your feet next to the stove, or keep the boiling water in the pot even on a swivel stove.... Lacking a freezer, and maybe confined to a small fridge: manage your provisions and your meals well. Some fruits and veggies (in those swaying nets!) will last for almost 2 weeks (potatoes, cabbages, carrots, oranges?), and some will last only for a few days (any soft fruits and veggies, bread,...) and are best kept in a fridge. Some food, e.g. cold cuts for lunch sandwiches, meat, etc. is best kept in the fridge and if well managed, will last well into your passage.
We keep 3 tiers of food and store accordingly: (1) short lasting: to be consumed in the first week - in the fridge (2) longer lasting: fresh food to be consumed in the first two weeks kept in nets and dry storage and (3) for ever lasting: canned, jarred or dry foods (or frozen in the fridge).
God bless you if you can bake your own bread/pizza/cake/cookies. After two weeks at sea, the cook becomes the hero. And bless the cook who can dish out a savoury meal after two weeks at sea without a fridge! And heaven-sent is the smell of freshly-baked bread or pizza a week into a wild crossing!

Itinerary and weather routing

Moving on.., but no less important though! No matter the safety equipment, how well the yacht is equipped, with the best cook and food, if I can not agree on a sound (and in my mind "the right") overall itinerary with the skipper, I will hesitate to step aboard.
First of all, good weather routing software/apps are a must. Forecasts to be downloaded daily. I swear by Predictwind's ECMWF forecast (with the GFS model as a backup), for wind, swell, precipitation and CAPE (lightning!) forecasts. AND I like a way to download those forecasts - in high resolution and over a wider area - fast! ("Hurray to Starlink!" - higher res forecasts over a larger time-period and larger area via Iridium Go take forever, argh!...)
But even then, a solid overall routing plan is a must, avoiding the turbulent areas, favouring the -maybe slower- trusted routings. E.g. In an E-W transat, I favour the longer route to go down to 12°-11°N or even 10°N to avoid wind-still or even upwind turbulent areas. Longer, but safer, is what I like.
Note: I take Predictwind's automated weather routing as "advice", but always make up my own mind what route I want to take, based on an overall weather systems in a wide area.

Emergency procedures and basic rules

I have crewed in trans-ocean sailing yachts where the safety briefing took 5 hours and on other yachts where we never got a safety briefing.
I like to sail on a yacht where the basic emergency procedures and rules are clear. E.g.: Safety jackets on between sunset and sunrise and with windspeeds above 20 knots. No-one on the bow at night unless a 2nd person is present in the cockpit..., etc
But also basic procedures like "what to do in case of MOB ('(Wo)Man Over Board' - my nightmare scenario), and a clear agreement on the chain of command if the skipper becomes incapacitated, are a must. Or even more basic: what are the rules on the consuming alcohol onboard? On my past passages, we either agreed on "no alcohol" or "one beer only at sunset".
Or more basic: in case of emergency: who to contact on what telephone number, in what way, giving what details, for what purpose?

Crew and watch systems.

Sure you can sail across any ocean single-handed, or short-handed. This might not be the most comfortable and enjoyable crossing you had, though. Depends what you look for and prioritize: excitement, comfort, or safety,..
I sailed a 72ft racing cruiser with only me and the skipper. And I loved it. For 5 days. Not sure if I'd like to do this for 2-3 weeks in a row, with 4 hours on and 4 hours off watches (and cooking, repairing, cleaning in-between)...
An ocean crossing should be an adventure to enjoy, according to me. Running with two people for days and weeks in a row, might not allow you to fully enjoy the unique experience an ocean crossing offers you. Crossing shorthanded is perfectly "doable", but is that what you want?
An additional note for families with young kids: I met loads of boats with only mum and dad, and 2-3 younger kids, who cross oceans with the goal of making this "a true family experience". My hats off to them, but if I were them: I would take 1-2 additional crew on board: If not for safety (in case anything happens to one of the parents, or one of them is not feeling too well for some days), then it would be to also spend more time with the kids - who need to be kept safe, and "busy" too: Ocean crossings are typically very boring for younger kids. Talking to many "family-cruisers" with kids, after their passage, most regretted not taking some additional crew onboard.
Ideally, I'd say a crew of 4 sailors is a good quorum. This will allow for a watch system of e.g. 4 hours on, 8 hours off watches, with one of the crew, every 4th day, responsible for the "mother watch": cooking the main meal, cleaning and general house keeping. More crew than 4, is a luxury - and will need more food/water/space,... Less will be more stressful. Your choice to make.
Apart from the "system" of keeping watches etc.., I am picky on how the crew is selected. Are they actually sailors? Have they lived in closed quarters with others before? How do they handle stress? What are their personal goals for this crossing? Are they fit? Do they get sea-sick? The smaller the crew, the more critical the people you select for a crossing. Luckily for you, dear skipper, there are LOADS of people looking for a crew-spot, sharing the crossing's food cost, who are very capable (and often ocean-crossing-experienced) sailors.
As a skipper: select your crew well. As crew: select your boat well, as, believe me, it is the "people" which will make this crossing a heaven or a hell for you.

I hope this basic checklist helps you in preparing for safe(r) and enjoyable ocean passage! The better prepared, the more you will enjoy those fabulous ocean sunsets, the stars at night, the pod of dolphins swimming at your bow, with the wind in your hair and the salt on your skin.