The Offshore Voyaging Reference Site

Going Up The Mast at Sea

This article should not be acted on without reading the entire series.

So far in this series we have covered a huge amount that, together with a careful read of the excellent comments thereto, will enable each of us to come up with a mast-climbing system that meets our needs and tolerance for risk—there is no such thing as risk free.

But what happens if we need to go up at sea? Let’s take a look.

First off, we need to clearly understand that going up the mast at sea is one of the most challenging and dangerous tasks a sailor will ever be called upon to do.

I can’t overemphasize this. We can go up the mast hundreds of times when the boat is at rest in smooth water with a system that works perfectly for our needs, and still be totally unprepared for going up at sea when the mast will be swung through a huge arc by swell, even on the calmest days.

The Reality of Mast Climbing at Sea

Just imagine for a moment that the boat is rolling 10 degrees (not much at all) either way and the masthead is 60 feet above the water.

That means that the mast will be swinging through a distance of nearly 21 feet (6.5 meters) on each swell.

Wait, it gets worse. Say the wave period is 5 seconds, which is quite typical offshore in light to moderate weather. Then we will swing through that full arc—assuming no damping, more on that in a minute—at an average speed of 4.2 feet/second.

I know, that does not sound too bad, after all it’s only 2.8 miles per hour, but wait, it gets worse again…much worse. Every 5 seconds we will be decelerated to zero and then accelerated back again to the same speed in the other direction.

And it’s that acceleration and deceleration that can, if we lose our grip and swing clear, smash us into the mast that is likely coming the other way at us with crippling force. How much force? Sorry, way past my math abilities. Let’s just say this is really going to sting.

But wait, it gets worse for a third time. The movement of a boat offshore is not in just two directions, as I have portrayed above. It’s multi-dimensional, with pitch and roll mixed together in unpredictable and ever-changing ways.

And then we need to remember that wave height and period are not constant at sea. So every so often a wave will come along that’s at least twice as high as the others and can catch the boat wrong-footed, perhaps rolling her to 20 degrees either way. It only takes one of those to perhaps pry our terror-fuelled grip loose and set us off on a wild free swing, ending with being smashed into the rig.

OK, now imagine it’s blowing 25 knots and the significant wave height is 15 feet…wait, let’s not, too terrifying…anyway, I’m sure we all get the picture.


All of the above applies to monohulls, but what about multihulls? One could be forgiven for assuming that their huge form stability solves the problem, or at least makes mast climbing easier.

And that’s true in small waves where the width of the hull spans the entire wave length, but as soon as the wave length exceeds the beam of the multihull (or length if bow-to the waves), which happens at quite low wind speeds at sea, everything changes.

And when the distance between crest and trough (half a wave length) equals or exceeds the multihull’s beam, the cat or tri will immediately roll to conform to the angle of the front and back face of each wave, without the damping of the monohull’s keel and ballast, resulting in a more violent motion, albeit at lower amplitude.

This is not intended as a criticism of multihulls. In fact, I’m a big fan, to the point that a trimaran was on our recent boat-purchase shortlist. My intent is only to point out that multihull owners need to read on, too…so don’t go all clannish on me, OK?

Do We Need To Do This?

Given how dangerous mast climbing at sea is, before we get into the how, we need to think about whether we are even going to go up in a given situation…i.e. the if. So let’s look at that:

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Drew Frye

What do you use for a helmet? On my last boat I would have a bike helmet available–something, but not best. Now I carry a Zihk H1 that I like (low boom). In fact, my regular sailing hat has a bump cap insert (I don’t have enough hair to ward off companionway bumps anymore).

Drew Frye

In fact, climbing helmets, like hard hats, are more intended to protect against falling objects (rocks) than side impacts. They’re really not what the salespeople think they are. The helmets used by sailors are watersports helmets that are optimized for side impacts.

But I’m sure it will serve your purposes.

Drew Frye

EN1385 is the standard for kayak helmets, and most of the pro sailing helmets you see are built to that standard. Examples include the Protec Ace Wake and the Zhik H, seen on a number of AC boats.

Another problem with many climbing helmets is that because they protect against falling objects they sit higher on the head, making you head a taller target for the boom.

Stein Varjord

Hi John,

Sweet Protection is a company I actually used to know a bit. They make high end sports helmets and more in Trysil, Norway. Really good stuff. I used one of theirs looking just like that one for downhill biking. However, I think it’s perhaps an overkill to go for this price and protection level. Since we plan to never climb the mast at sea, price per use minute gets astronomical. It’s also too weird to go Darth Vader when sailing, so something that would be comfortable and ok in bad weather might be a smarter investment?

Some years ago there was indeed a sailing helmet that has a full face visor integrated. It would slide up inside the helmet when not in use. The helmet covered the whole head and was reasonably low profile. Thin layer. Don’t remember the brand. It was used much on the 60 foot ORMA racing trimarans and Volvo race boats some 20 or more years ago… I’m not on the scene anymore so maybe still? The great benefit was to protect against the constant blinding high speed spray. It looked very much like this surf helmet: Perhaps one could add a hinged jaw protector on that? This helmet stuff was really a lot more comfortable than the hood of the jacket. Maybe worth considering for general foul weather gear, with additional functionality?

With kayaking and biking we need protection from impacts on sharp objects at pretty high speed and energy levels. Even though the rig can really hurt us, the impact speed and forces are much lower. We just need help to not slam our head or face on the mast. Doing that can disable us momentarily, which will certainly have dire consequences.

I think the cheapest stuff available should do the job just fine, but this is just a guess. Maybe ice hockey has something suitable? A shell with a wee bit of padding? We don’t really need a full face protection, just something in front of our jaw to take the bumps, rather than our teeth. A curved tube or so would probably be fine.

Stein Varjord

The above mentioned one is actually the helmet I was thinking of. Perhaps the visor could be enough to fill the face protection purpose? I’m somewhat doubtful, but maybe?

Drew Frye

The visor helmet was probably a Gath Surf Helmet. My understanding is that they are not built to EN standard (because they don’t feel it is the best standard for what surfers need), which does not mean they are not good helmets.

Ernest E Vogelsinger

Do a search for EN1385, as Drew mentioned. There is a helmet designed around this norm especially for water rescuers, at least in Europe named “Palm AP2000”, available from miscellaneous outlets for EUR 45.-.

Eric Klem

Hi All,

I was curiously watching where this helmet discussion went, it is not a subject that I know a lot about. The helmet that I use is my old whitewater kayaking helmet but I don’t know if it is the right or wrong thing to do. I had 2 friends get knocked out paddling in around 2005 with reasonably hard hits but the type of ones that were not uncommon. As a result, a few friends started researching helmets and felt the best ones available at the time were from WRSI so all of us got them and to my knowledge they worked fine and do claim to meet EN1385. They have a hard plastic shell, foam inside and a good strap system and are supposed to be designed for multiple hits. At the time, most other kayaking helmets were some combination of huge, awkward fitting, homemade or worse so these really seemed like an improvement.

Around the same time, “full face” helmets started to actually go a bit more mainstream in the creeking community (people paddling very low volume and very steep stuff like you would see in a video). Prior to this, there were bolt on face masks that some people used but it was rare. These looked kind of like hockey face masks but there were fewer larger diameter bars. There were some rumors floating around about these being able to get hooked in strainers (fallen trees in the river) but I have no idea if that ever actually happened. I think the wide adoption of full face helmets was thanks to the chin protector type design like a dirt biking helmet and like the one John linked. I can say that after they came out, I don’t remember ever again seeing a bloody face which used to be kind of common. I never hit my face on a rock but did break my nose twice from my own paddle on big waterfalls, both times prior to have a full face helmet. Some helmets also had 1 metal bar down the center running from the top of the helmet to the chin strap. The WRSI helmet I have has a removable chin guard. I only paddled whitewater for another 4 years or so after getting this helmet but it seemed to serve me well although the attachment of the chin bar did not inspire confidence in me. I have not used the chin guard when climbing the mast ever but I have it there and would use it if there was a lot of motion as it is pretty unobtrusive.


Stein Varjord

Hi Eric,

Interesting observations. Makes sense. As mentioned, I strongly believe that a helmet for going up at sea needs some level of face protection, which you confirm.

However, as also mentioned, the main conclusion of this discussion seems to be (I agree): Do NOT not go up the mast at sea. Buying a space consuming helmet at +500 Euros/Dollars, which we plan to never use, doesn’t make sense.

To make this useful, we need something that is:
– Really cheap and can be stored compact, and/or
– Useful for other far more frequent situations,
so we’ll actually want to have it. If not, the whole helmet issue becomes a nice to know theory that very few are actually equipped for. Not in line with the attitudes of this awesome site.

Helmets around 50 Euro/Dollar were mentioned in a comment just above by Ernest. That seems about right. Maybe one such has a face protection bar that can be attached? Maybe there is some very easy DIY method to add one ourselves? I can fabricate one in composite, but that’s not very easy for most.

As mentioned, I believe, (I may be wrong), that the forces we need protection from are much less than we need for some biking or white water sports. That seems to indicate that some cheap and compact construction would be good enough.

When we’re sailing in foul weather, we’re wearing something on our head, usually the hood of the jacket, perhaps a wool hat. Those give no protection against head trauma. That’s more likely to happen on deck or in the cockpit than when climbing the mast, because of the time we spend in each situation. If our foul weather head gear was a helmet, that would be wise. However, that change will only happen if the helmet:
– Is clearly more comfortable than the hood, and
– Makes us feel even cooler.

(I stopped denying my vanity long time ago…) I don’t see a complete answer to all the needs yet, but it seems like we may find usable answers here. So, as I see it, what we need is probably:
1. More comfy in foul weather than the hood
2. The looks makes us feel cool
3. Has some face protection
4. Cheap (depending on the degree of nr 2)
5. Compact

Arne Mogstad

I think I mentioned it before, but maybe avoid the type of helmets that are made of “styrofoam” and designed to absorb the impact. They are usually a “one-hit-wonder” (take one hit, then they provide limited protection). Rather choose helmets designed to deform, as they can take multiple impacts. Because if you get hit once, the rig will come back again and might hit you, again… That pretty much excludes most bike helmets etc.

Modern climbing helmets do not have the same high-rise form, and do protect fairly well against side impact. The exact helmet you already have John, I would say is a very good helmet for this purpose. You don’t want something too restrictive either. A motorcycle helmet might give decent protection, but you won’t see well, and that is also a risk.

Realistically, bringing a full-face style helmet offshore, is way beyond what I will ever do. I bring a similar style helmet as yours John, and I am very happy with that. The head is not the only thing that can get hit bad and will deal a SEVERE amount of injury. If we go down this road, I would say that bringing a protective vest, similar to what horseback riders, motocross riders, and downhill skiers use would be more beneficial. As going skiing is something I tend to do while sailing, I actually often have one onboard, but that is purely coincidental, and I would probably not have thought of using it if I happened to be in that situation before today.

Drew Frye

The “protective vest” can be a type III waterski or whitewater vest, not a bad thing to have for the dinghy, hull maintanance, kayaking, and general knocking around. Variations are often used for whitewater rescue (MOB recovery can be similar) because they allow swimming AND protect the ribs). Inflatable PFDs are neat, but they don’t serve all purposes. Underfoot in the dinghy they won’t last, and imagine trying to re-board a kayak wearing an inflatable–self rescue is basically impossible unless you defalte/reinflate, and they it simply adds sodden weight while reboarding and may be a hazard if you are reboarding in steep chop or surf. Every cruising boat should have at least one sturdy non-inflatable type III PFD. The one time I went up the mast underway I was wearing a type III, and I suspect it prevented a few rib bruises. Certainly, it allowed me to brace against the mast and concentrate on the work. No helmet, since we didn’t have on on-board that time.

On my F-24 (sporty boat with low boom) I sometimes wear a Zhik H1 with a balaclava under it when singlehanding in breezy weather in the winter. It seems higher consequence, as you said. I always were a bump cap insert in my sailing cap. Why not, it’s comfortable and helps keep my hat on.

I believe all whitewater hats are designed for multiple hits. Really, it is only bicycle helmets that tend to fall apart, and only the cheapest ones.

Charlie Armor

Whoops, already mentioned

Alastair Currie

I went up the mast on a Jeanneau Sun Fizz (38′ LOA IIRC), off Portuguese coast, Atlantic swell, calm conditions. It was a big lazy swell, long wavelength and low period. The mainsail was jammed at the top of the mast, halyard jumped the sheave, and I went up to open the shackle. Back then it was a sit in type of bosuns chair, hammock style that cinched in around the hips as the weight was taken. I was skipper and we did discuss the swell and roll and decided that I would not risk (paying) crew. I was raised on one of the other halyards (it would have had twin genoa and spinnaker halyards). A safety harness tether was used to secure me to a shroud and a tail line was used back to deck. It was a bendy, skinny racing mast. I can remember using my legs and arms to grip the mast and mainsail, like a human genoa, luff pre-feeder. At first it was no big deal until about the first shrouds. The overriding memory was at the top of the mast when it took all my effort to hold on, and then working up the courage to get the pliers out of the pocket, then again to use the pliers to open the shackle. Coming down was easy. The next day I was all bruised, arm and leg muscles were aching. I don’t recall if I attached the safety tether to the shrouds until I got above the first spreaders, but I do remember when descending that the safety tether went tight because I forgot to disconnect it. I think I had wrapped it around the two cap shrouds when I got to the top to help hold me secure. That was the one and only time. If it had been rough, or the period higher, It would have been very difficult if not impossible. I am now much heavier and not as strong as I was back then. My own boat has mast steps, not sure how they would have helped as clamping / gripping the mast as I was pulled upwards, lowered downwards held me in place. Lifting a hand and foot off a secure mast step, or negotiating around each mast step may have been more risky.

Alastair Currie

At the time the tail line was probably thought of as a good idea which was not tested in real life. I have experience of tail lines used to handle loads lifted by the vessel crane. The lines are just to move a load by say swinging a corner into a tight gap; the crane is supposed to do all the work. I have seen people flicked up and dropped onto the deck and even flicked over the side of the vessel. Both these incidents due to load swinging rather than crane operation. I guess the point is that the momentum of a human being swinging at velocity, is not going to be easily stopped by someone hanging onto a tail line. If such a tail line was used, it would need to be controlled. Perhaps similar to the hoisting halyard, by friction, say via a snatch block at the base of the mast back to another winch. Or perhaps rigged to free run through a jammer when hoisting (with stopper knot), the jammer could be applied if the person swung out and the tail line used to pull them back close to the mast. Then we are back at the issue with shorthanded crews controlling two lines; the jammer option could be a solution to regaining control if the swing risk was realised.

Alastair Currie

Regarding the low velocity of a roll.

My employer uses a “convincer” to persuade people to wear seatbelts. It consists of a car seat, with seatbelt on a sloping track. The seat has a velocity of no more than 3mph when it strikes the stops. Everyone comments on the force of impact at such slow speeds being significant. Swinging back in and striking a mast, could easily result in life threatening injuries.

Alastair Currie

Replied to wrong comment.

Matt Marsh

John wrote:

The one change I think I would make to the backup is dispensing with the bosun’s chair or other separate fall-arrest harness in favour of attaching the backup to my climbing harness.

Yes, I know that breaks the fundamental rule that backup systems should share no components with the primary system…

I would clarify that to read “backup systems should share no components that could fail with the primary system….”

A proper, well-fitted harness with appropriate OSHA etc. approvals is not going to be at significant risk of unexpected failure. Having both your primary and backup fall arrest / fall protection attached to the same harness (albeit on different D-rings) is completely normal, provided that the harness is in fact designed for climbing and work aloft.

You use separate halyards, blocks/sheaves, winches, hardpoints, etc. for primary and backup because those things can and do sometimes fail unexpectedly. But the harness itself, assuming that it’s of a suitable type to begin with and that you inspect and maintain it, won’t.

Eric Klem

Hi John,

All of this makes sense to me. I have spent a fair amount of time aloft while underway but in a very different context on boats that require work aloft to furl, tack, etc. and have provisions for it. I can say for sure that it was terrifying the first time I did it but got better with time. Some of the accelerations could be quite high and dangerous plus they can be unpredictable, it really feels like a lot of lurching in some sea states. Just being aloft in calm water with normal heeling even in gusty weather is no big deal but the minute the swells show up, it is a totally different ballgame. The people who worked on the big Windjammers going through the southern ocean in the middle of winter must have been absolutely amazing, I can’t imagine trying to work out on a yard in conditions half that bad. And like you, I have no real experience aloft while underway in a harness or bosun’s chair. I completely agree on prevention being the best bet and then thinking very hard about whether climbing is truly necessary.

The key to climbing traditional rigs was that you were climbing with both hands and both feet with them all spread out horizontally. Sitting in a harness I find to be very non-ergonomic to brace yourself. I think that the issue is that it is very hard to resist the yaw moment. Roll and pitch manifest themself as yaw when you are attached radially up high to a thin object like a mast. The actual radial forces from yaw and pitch are significant but totally manageable. It wouldn’t be nearly as bad if we had hand and footholds spaced nicely 2 to 3 feet horizontally apart but just trying to wrap ourselves around a wire or the mast, we yaw around a lot and use a lot of muscle power trying to grip tight enough to counteract it. I have never tried it but maybe putting a really tight spare halyard (if you have one) from masthead to deck a few feet away from the mast and keeping a hand there and one on the mainsail luff might work well as then you can actually apply torque? It would become much less effective towards the top of the rig but you can probably grab a cap shroud at that point. Climbing ratlines actually has this issue too, they are not too bad until you get within maybe 10-15′ of the top when the stays get very close and you lose your leverage and you start yawing a lot.

On large enough boats, a very effective climbing technique is to actively climb up the sail slides like a ladder. This requires a pretty large boat with appropriate vertical slide spacing or a gaffer with mast hoops for the gap between the luff and mast to be enough.

You can also climb 2 parallel wires quite effectively and I have used this to go up lower shrouds quite effectively. The technique is to put your knees inside the stays and hook your foot outside allowing you to clamp hard with your legs. By alternating clamping with your legs and pulling yourself up with your arms you can climb surprisingly well.

I know quite a few people including myself who have had to go aloft due to flags getting sucked into a sheave preventing a sail from being lowered.


Eric Klem

Hi John,

Yes, I think what you propose for attaching the halyard far outboard probably makes sense. And yes, it would definitely need to be high modulus and preloaded quite hard. The problem on a lot of boats might be where to attach it on the bottom end. It definitely wouldn’t stop all motion but I think it would really calm it down and cause the user to use a lot less energy. Of course, I am not dying to try this idea for anything other than a relatively calm water trip up the mast.

If anyone has tried this or can think of an issue with it, I would definitely be interested about it. I hope to not have a reason to try but you never know.


Stein Varjord

Hi John,
While reading I felt the urge to add exclamation marks all over the place. Nothing here is exaggerated. I have enough painful experiences to keep me alert. I’ll do every thinkable effort to make climbing the mast at sea a never event. I’m healthy and not at all afraid of climbing the mast. The reason I strongly want to avoid it at sea isn’t fear. It’s awareness that going up usually just isn’t going to work.

You mention catamarans. As you know, I’m definitely part of that clan, but I won’t say anything against your warnings. Having been up several both racing mono and multi masts at sea, I’d say it’s far worse on a multihull. The low amplitude that makes a cruising cat so comfortable at deck level is far from low when you’re high. Motion distance multiply with height and frequency stays close to the same. Some more mass up there won’t help noticeably.

That means acceleration enough that even an arms length distance from the mast can break bones and destroy your face. The latter is a serious issue. I strongly recommend a helmet with a jaw protector. It doesn’t need to be big, as long as it has something to help protect the face and head from hard surfaces. Perhaps something from ice hockey or American Football? I didn’t have this, but wish I did. I’ve never come down without bleeding at least a bit from somewhere. If a cat mast had steps on it, (probably doesn’t exist?) I would definitely not consider climbing it at sea. Might as well put up some knives there too… 🙂

On big racing multihulls my experience has been that the best was to head straight down wind and significantly reduce sail area until the speed was slightly slower than the wave train. That slows down pitching a lot and the hulls will mostly stay on the same wave, preventing the very violent sideways motion when one hull crashes onto a wave. However, I think this downwind method demands a skilled helm and crew. I wouldn’t trust that this is a good solution for a cruising cat, but it might?

Heaving to does significantly reduce amplitude also on a cat etc, but not enough to compensate that this orientation, not far from beam onto the waves, makes the boat contour the waves. Brutal stuff.

I also strongly agree that a bosuns chair is just not safe for this potential rag doll in dog’s mouth experience. I’ve had situations where I’m strapped to the mast, but my body behaves like a flag from side to side, fully horizontal attitude both ways. That never ends pain free.

I’ve used a climbing harness with shoulder straps and an extra ring higher up. I think it might have been Petzl and made for arborists, but it was 25 years ago last and not my equipment, so I don’t remember properly.

It was also adapted with two lines that both had a small snap shackle at one end and went through an eye via a cam cleat for each, attached flat on either side of the harness. The tail outside of the cam cleat was tied on the harness. The point was to operate it fully with one hand only. Put the end with the snap through what you want, snap it to the harness and pull in the slack on the other end. The cam cleats and snaps made it quick enough in use to actually do it. Far from enough to be safe, but a very good help for work ease and hurt prevention.

I actually think as you John, that especially on a short handed cruiser, the good choice is quite often; just accept that it can’t be done. If that means a danger of losing the rig, so be it. Also losing a crew member won’t help…

Drew Frye

A very recent fatal accident involving climbing the mast underway. The crew became injured and terribly tangled. It’s a gruesome tale. The kind you wish you had not read.

Michael Jack

I thought I was going to vote for a single-handed article until reading this one, John (thanks). If you can avoid going up at sea for so long I am certainly going to continue doing so as well. The only time I have been on boat when that happened was so distressing, just about every time I look up at my own mast I think of how close we came to disaster that time. So I am going to try and avoid, at almost all costs, going up at sea. Going up in a harbor where I can probably get help from others is a much better option.

Alastair Currie

A description of how Ellen Macarthur climbed the mast solo. It is light on technical detail but confirms that going down wind with the waves is a positive help; used an external halyard and jumars.

Matt Marsh

That’s certainly an interesting observation.
That said, I would use some caution in considering how the experience and technique of someone who is undoubtedly among the ten finest and most skilled skippers in recorded history might translate to an average cruising boat!

Anton P.

When I was the bowman on a V60 about twenty years ago I once had to go up in heavy seas and +35 knots to trip a blocked Martin Breaker which locks the halyard of the 1.5oz kite we had up. I was pulling so much G’s up there that I puked from the top of the mast! Ever seen one of those centrifugal simulators where jet pilots get trained not to loose consciousness?

I came down with a broken rib (found out a few days later), various bruisings and a crushed finger. The right hand sole my Chameau sailing boots had a cut in it that if I would have worn anything else I would have been seriously injured. I remember being stuck between the diagonals and the mast a few times.
My mates had rigged me the windward spi halyard behind the shrouds to keep me guided close to the mast but I mostly grabbed about anything I could to keep on the rodeo ride. Climbing harness, no helmet (helmets are for pussies), pitch black night.

It was a dirty job but someone (the bowman) had to do it because we were roaring for land and a gybe was out of the question. I was 27, all muscle, balls of steel. Never again!!

Anton P.
Simon Robinson

Given the context from this article and comments, that is one SCARY stunt!

Iain Dell

There’s a very timely article in the latest (March ’23) edition of the UK’s ‘Practical Boat Owner’ magazine of a lady who got stuck up the mast of her Oyster 56 trying to free their stuck Code 0 on an Atlantic crossing with squalls forecast.

A gust knocked her off the mast, jammed her harness and repeatedly swung her into the rigging in a 3m swell. “The fall preventer was attached too high and was pulling me up”, she said. “Each time I slipped, it kicked in but I was forced to go higher to release it while trying to hold on with both legs and one arm”. While trying to release it, another gust again flung her into the mast tangling her preventer around the shroud 3ft away and she was forced to disengage her safety line. Thankfully, she escaped with only minor injuries but it must have been a very traumatic time both for her and her husband, who because of the conditions couldn’t hear each other.

The article concludes by stating that they’ve now bought an attachment for the Bosun’s Chair which slows the ascent, but stops it from swinging out more than half a metre. However, I loved her final words on the incident: “At least the rest of the crossing felt very calm by comparison”!

Dick Stevenson

Hi John and all,
Sobering stuff!
I would probably contend that the only reasonably safe place to go up a mast is in a marina or tied to a wharf. I have been up the mast at sea only to the lowers completely uneventfully and used usual procedures adding only a helmet.
I say the above as, my worst experience up a mast was some masthead work in a small secluded anchorage. A medium sized displacement powerboat came in and circled us at speed with all on board looking and pointing at the silly sailor up the mast. After two turns enjoying the spectacle, someone noticed the masthead movement and my desperation holding on and they took off with a wave.
It was decades ago: I believe my grip (legs and arms) let go at least once and I was very glad that I was at the masthead as there was little free halyard so any movement away from the mast was limited. I was terrified, especially when they went for the second circle, but I was also glad I was not lower down where breaking loose from the mast, I would have swung farther out.
It was in a convention but higher end bosun’s chair of the kind one got at Defenders or West Marine at the time and I slid around in it a bit (unsettling), but never felt I would slip out. I do know I quickly bought a Brion Toss harness-type bosun’s chair which I felt to be much more secure, which I have used exclusively for decades now. I sort-of remember experiencing the question:  “Do I hold onto the halyard with both hands when things got boisterous (to ensure staying in the conventional chair) or do I hold onto the mast?  With the BT harness/chair, I do not feel any need to hold onto the halyard and always have both hands free for holding onto the mast or other work.
Random remembrances and thoughts, Dick Stevenson, s/v Alchemy

Karl Coplan

Here’s a trick I used recently in the “avoid going up the mast if at all possible” department. If the problem is just a halyard lost up the mast, and you have a backup halyard or topping lift in the right place, send a treble fish hook up the mast with the spare halyard and a very well secured retrieving line. You can swing the hook around until it snags the lost line, then pull both halyards back down with the retrieving line.

Admittedly I didn’t think of this until safely docked in Hobart after a passage from Eden where our topping lift/staysail halyard unsnapped itself from a flogging staysail. But there’s no reason it wouldn’t work offshore.

Matthew Dehn

has anyone used a SWI-TEC mast lift system? seemed like a good system although not cheap.

Eric Autenreith

Just as anecdote- many years ago- 1970, 42′ Creekmore yawl, rounding South Africa, night time, ~ 40k, sailing with just storm jib, i was 14, on watch. Somehow noticed the forestay was slack. Brother Jim steered us off the wind, younger brother Arch and Dad hoisted me up the mast on the basic wooden bosun chair. I did wear a life harness and clipped it on and moved it as needed. First trip up was to assess problem- bronze clevis pin sheared. Had to come down for tools and parts then back up. Was hoisted on main halyard. Used the spinnnaker halyard secured to forestay below the swage fitting to pull that into position the put in stainless clevis. i dont recall being scared at the time though now i wonder wth.
Things that made that work- children can be pretty monkey-like – strong for their weight so somewhat better able to endure the extra g forces. And there was a pretty good comfort level that happened just from play. Good steering- downwind eased the motion and reduced stress on the storm jib luff cable and halyard which were keeping the mast from falling.
For years we climbed the ratlines to spreaders even under sail and played swinging in the bosun chair, and dunking while under sail. It could never have worked having little boys hauling Dad up the mast. Of course it could have all ended badly.
And obviously, who put that bronze clevis into stainless tang!?

Eric Autenreith

was thinking also, that our shoal draft boat was a pretty short rig yawl, designed for cruising Bahamas- mast height ~41′.
typical sloop- Valiant 42- has mast height ~58 ‘. Such a mast top would have about 42% increase in arc and accompanying velocity. Where force (in the change of direction) varies as to the square of velocity, i can see such a taller rig would have been a great deal more difficult and hazardous.