The Offshore Voyaging Reference Site

Going Up the Mast—An Industrial Fall Prevention Approach

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

[Before Matt gets going, a word from John.]

We sailors tend to be a close-minded lot, often thinking that all the good knowledge resides with fellow sailors, the more experienced the better.

But that’s often not true. For example, we almost all used sidedeck jacklines, and many of us used high-modulus materials for jacklines and tethers, before some rock climbers and engineers pointed out with irrefutable logic how ill-advised both those methods were—you can learn about that in this Online Book.

Given that, I’m excited that Matt is coming at this subject grounded in his industrial fall-protection training, coupled with his deep understanding of the forces at work from his professional engineering training.

Despite having climbed masts for some 50 years, I learned a lot from reading what follows.

If you have a sailboat large enough to cruise on, you’ll probably have to go up the mast at some point. This can be one of the riskier parts of cruising, particularly since many (probably most) of us don’t have the proper training, or the proper equipment, to do it safely.

And guessing, or relying on internet forum advice, can be dangerous—it only takes one error to cause a disaster we’ll regret for the rest of our life, whether that’s measured in minutes or decades.

Much of the risk comes from the rare, non-routine nature of the task. Unlike a cell tower technician or a mountain climber, who work at heights all the time and are (usually) well trained and practised, cruising sailors might only go up the mast once or twice a year. It’s easy to forget some of the details and special safety precautions if you haven’t needed them for ten months.

We should, then, give some careful thought to how we’re going to do this.

What follows is a description of how I do it, on my boat.

My approach is copied more or less verbatim from industrial fall-protection training, which I took back in my commercial construction days.

This is not necessarily the best way for you to do it, on your boat, but we can at least get an idea of the risks that must be considered and the industry-standard precautions to take against them.

I must emphasize that working at heights is not something to take lightly! I can tell you how I do it, but you are responsible for your own safety, and for obtaining any professional training that seems appropriate.

Login to continue reading (scroll down)

Inline Feedbacks
View all comments
Jeff Sowell

Hi Matt, nice write up! The one point that runs a little counterintuitive is the idea that bowlines should be used in lieu of halyard shackles – especially because you drive home the point of enormous dynamic loads if the climber falls. Bowlines reduce line strength significantly. A quick google shows the strength reduction to be between 25-40%; quite a range but significant nonetheless. (Arguably a halyard with a fancy core should not be the weak link even with a bowline.)

Anyway, long story short…we use shackles and will either tape or seize them with wire. We spliced the halyards and are confident that they were done properly.

Dan Perrott

A bowline (with a stopper knot) or a rethreaded double figure of eight is the standard way to attach yourself to a climbing rope. No fancy core materials. The reduction in strength should still leave your halyards way stronger than they need to be.
I’d probably be happy with splices I knew but never with any kind of snap shackle or someone elses/inherited halyards and splices
Also it’s quicker to tie a bowline than mouse a shackle.

Jeff Sowell

Fair points, but climbing rope is designed to absorb shock loading relative to a halyard.

Dan Perrott

Lots of good advice. As a climber I know I approach this slightly differently and have the experience to deal with it. I’ll try and keep this general without relying on specialist skills.

Importantly for me. If you are going up solo, don’t use the rear clip on a harness (For backup or anything). If something in your system fails and you end up dangling from it there is almost no way to sort yourself out. Or if the backup halyard jambs or has a problem it is very hard to untie yourself. I actually dislike them a lot.

I’m not sure I feel the need to back up a good bosun’s chair. Its a good idea though if you have any doubt about its integrity or it’s a DIY plank of wood with holes drilled in it.
I much prefer use a climbing harness if I have to up the mast at sea, I find it more secure, but definitely not as comfortable for working in aloft.

If using climbing ascenders. I prefer to use a halyard to pull up a dedicated rope. This way I don’t have to worry about damaging an expensive halyard, or the sheath slipping on a dyneema halyard.

Make sure your crew knows how to safely lower you. And let them practice when you are only a short distance up and can give advice. This also ensures a check on your leads to a cockpit winch to ensure you don’t get overrides.

Bring up a rope with you that will reach the deck from where you are working. You will forget a tool/tape/bolt at some point and it’s easier and quicker to haul it up than come down and back up.

If you don’t have any mast steps at the top then rig up a loop you can put your feet into. It makes a huge difference if you can (even temporary) unweight your self from your chair or harness. They can also give you a lot of extra stability and leverage while working.

I often use a short quickdraw (short length of webbing with 2 carabineers) to clip myself directly to the top of the mast. This allows me to sit comfortably and work a bit higher up.
Caution!!! if you do this. If you are unable to unhook yourself your crew at the bottom won’t be able to lower you down.

I’ve never done it but heard that the capstan on a windlass can be used for a powered assist hoist. I think this requires a very high level of competence from whoever is hoisting you.


Richard Ritchie

I would not advocate use of power hoist using existing capstan/ windlass etc without VERY careful planning. The person being hosted may easily be crushed. Control and communication is everything. I am sure John will follow up on this …

Richard Phillips

Good article – on a topic where there are many truly dangerous articles out there. I watched a few dozen youtube videos on solo mast climbing and I would say most of them were very dangerous indeed. I particularly commend the recomendation to use a harness on a safety line *seperate* from bosun chair; lots of articles miss that important point.

I do have some quibles though – and to be honest I don’t think the approach recomended here is *sufficiently* safe to recomend.

I don’t agree with the comments about climbers: in almost all circumstances a well trained climber will identify safety problems with a sailors approach to mast climbing. This is what they do – and whilst most climbers don’t know sailing, they *do* know rope work.

Any climber trained in the last few years would not use a bowline: that is now considered dangerous practice and they would use a double figure of eight instead. Don’t believe me, pop down your local climbing wall and ask!

The article refers to a crew member tailing the safety line – without saying *how* they are tailing: a few turns around a winch is not a safe approach at all: do what climbers do and have them wear a harness and use a proper belay device. And that means, they should be *trained* to belay a safety line: if they are not trained, it is not safe and you need a different approach.

A winch is *not* a belay device.

And use a dynamic climbing rope for the safety line. Consider fixing this off and raising a prussic up this as you go, so you are in control of your own safety and avoid the risky and likely untrained crew member tailing you.

A proper climbing rope has lots of give so you don’t break your back if you fall a couple of meters. *Never* use dyneema or similar for a safety line – most halyards are less than ideal for the purpose because these will have been selected for their low stretch character.

I know a following article will get into solo mast climbing, but this is one of the best mast climbing videos I have seen. I use a similar technique but with a Grigri on the ascender line and Asap on the safety line.

Richard Phillips

I would certainly agree that skepticism is needed – particularly in picking youtube experts. My training in climbing is well over thirty years old and not well practised since – but left me with a sufficient eye for good safety practices that I was utterly horrified by most of the ‘how to climb a mast’ youtube videos by sailors. The vast majority of these are terrible – and it led me into a little stint of climbing videos, which are *consistently* better on the basics of safety. My 14 year old daughter has been doing climbing courses for two years now – and even as a relative beginner she could make me a veritable list of safety failings of the sailor videos.

I maintain however that your reliance on a crew member tailing the safety rope with a winch is a significant safety risk in your system. It relies on perfect winch handling at the exact moment of a fall. All it would take is an absent minded crew member re-winding the winch after a riding turn, at the wrong moment, and you are dead or badly injured. It does not fail safe. In particular, on the way down, the crew will take a turn off the self tailor and manually feed rope: your life depends on them doing this correctly even when there is a sudden and *massive* load (even droping a couple of foot is a huge load).

Although I agree with your points about fall arrestors to a point – I am not sure you have considered all the options in this department. I use a Petzl ASAP *without* the additional absorber – so this is NOT single use. Indeed I have tested it a couple of dozen times. Importantly I use a dynamic rope as a safety line as this has some give, and I clip the asap to my harnes directly (or with six inch loop) so it is never far behind. This way, I don’t depend on anyone else for my safety: if I fall, I drop only a few feet on a springy rope and by ascending a few inches can release the ASAP and carry on. Nothing one use about it. Of course a prussik on the safety line to your harness also works well, but needs to be manually moved up as you go.

Stein Varjord

Hi Richard and Matt,
I also struggle with trusting someone on a winch. Maybe I’m a control freak. “Maybe”, ha! 🙂 Either way, when I’m climbing a mast, there is not a single second that I don’t control safety myself.

I can use various methods for getting lifted, normally someone on a winch. For safety backup, I always use a separate rope that remains fixed and tensioned a bit during the whole climb. On that I run a sliding Prusik knot.

I have a small steel ring just under it. That ring has a shock cord running freely through it, which has its ends hooked at the top of each of my shoulder straps. This keeps the Prusik knot always pulled relatively tight as high as it can get. Completely hands free. If the lifting line should let go, I cannot possibly fall even one foot (31-ish cm). Typically I’d say half that. I’ve tested it.

To descend, I have to hold my hand on the Prusik knot and pull it a bit down to let it slide on the rope. The pull from the steel ring hasn’t been a problem for me, but if so, the shock cord is just hooked on. Easy to release before descending. If something goes wrong and I fall, I just let go of the knot and I stop immediately. The shock cord and steel ring is not needed for this to work, of course. The fixed rope should of course be a hoisted dynamic climbing rope. At the moment mine isn’t, but I’ll fix that.

Richard Phillips

I think this is a sensible system. The most important bit is simply that the climber should have control over the safety rope so even if someone else screws up you know you are safe.

John Harries

Hi Stein,

I think the key weakness in your system is that all constrictor knots, including prussic hitches tend to loosen when we handled and slid down. Also, like the mistake I was making using a jumar for this, you are assuming you can, and will, let go of the knot fast enough in the event of a fall. I think that’s a fundamentally flawed assumption and it’s why I changed to an ASAP arrester. See part 3 for more on this.

Stein Varjord

Hi John,
This article series, and the many smart comments, has made me rethink my system. I’m not finished thinking, but it looks like I have to agree about the knot. I think it’s pretty good, and have tested if I can provoke it to fail, which is hard, but probably possible.

I think I’m smart enough, but with any type of stress, I need a system that I won’t mess up. Sooner or later I’ll act like a moron. The most probable person to kill me, is moron me. I’d prefer to not give moron me suitable “weapons” for that hit job. The knot with the bungee and ring tensioning it upwards is better than without, but I agree that it might still not be good enough.

John Harries

Hi Stein,

From one moron to another, I think yours above is the smartest comment so far.

Alex Borodin

Very good info. I would only add one minor point on knots for tie-in. At the Bavarian Mountain SAR organization (which is where I learned how not to fall), they allow two knots for tying in climbing rope to the harness: figure eight follow through and the bowline on a bight, tied through the harness (by following a bowline backwards with the tail). The bowline on a bight is my preferred knot, because it’s considered as safe as figure eight and yet is easy to untie even after a hard fall. IMO, this knot deserves to be wider known.

Personally, I prefer to climb the mast solo. That way, I don’t need to stress the crew by forcing them to take an exam on safe belaying. They only need to know how to lower me safely if I’m unconscious, which is much easier.

Richard Phillips

Yes, you are right – I have heard the same two knot standard is common elsewhere. At my daughters climbing club they have a one knot – figure 8 only rule because they think it is easier to buddy check that is correct: it is obvious if it is right at a glance.

I also prefer solo. The first time I climbed a mast I did so under the instruction of a competent *climber* and his safety rigour convinced me that I should not trust most sailors on this one!

I hoist a piece of 10mm dyneema as my ‘climb’ rope (could use halyard but I don’t want to damage it), with foot loops to an ascender and a Grigri to ratchet my way up.

For safety, I hoist a 10mm dynamic climbing rope loosly tied off at base of mast. To this I attach a petzl ASAP to my harness.

Working well so far, and coming down is very smooth and fast. I originally used a prussik to the safety line but having to move it constantly is a bit annoying; the ASAP moves with me both up and down.

Randy Reese

John and Matt,

Thanks for the insights. And thanks to the other commenters.

As a solo sailor often without crew to help go aloft, I’d be interested in a follow up article or comments about safety and strategy for going aloft without crew, particularly keeping a safety line tight while ascending. I know, not ideal but it has to happen sometimes.

James Evans

I used to use an 8:1 tackle hoisted to the masthead with a ratchet block at the top and an ascender on the fall. Easy to hoist oneself or lower. However, it’s a load of rope and potential for getting left up the mast if it tangles. As for the rest of the gear, the least said the better. I’m still alive but by luck, not judgement. The only time I fell was only about six feet, but believe me that’s enough to get your attention.

John Harries

Hi Jim,

Very good point about all the potentially dangerous stuff people like you and I have done over the years. Starting from that point, rather than “I have all this figured out” is probably the most important step to safe mast climbing.

That’s going to be the thrust of my article on the subject. Or said another way, doing dumb shit so you don’t have to is just one of the services we offer at AAC.

When we publish that, I hope you will share some of your single handed experiences and the trade offs between climbing safety, and safety of the boat if I don’t do this by myself.

Peter Sweitzer

So, this technique is not advised?

I do like and will add a separate harness attached to a separate fixed line. Up to now, I have attached a prusik directly to the bunson chair. With the separate harness, if it were to fail, I can disconnect and still be lowered.

Arne Mogstad

Great topic and article!

I’m a climber and both professional and volunteer alpine rescuer, and a few things strike me, so here’s an embarrassingly long comment…

As already said, bowline is generally considered a no-go. To further expand on that, the use of knots at all is a big controversy on super-static ropes (like dyneema). I use locking-gate climbing carabiners, and/or a climbing rope.

Consider using a “downhaul” if going aloft offshore. Heeling over you might end up over the side when lowered down.

I do not agree in the use of belay devices and doing “climbing-belay”. If your boat have large winches, they are able to hold fairly big loads. But most of all, when belaying, you need a trained belayer, and the rope to come down to the belayer from the masthead for them to not be pulled horizontally towards the mast in case of a fall. The belayer should not stand under the mast if possible.

As mentioned, safety lines should be dynamic (basically this means climbing-ropes). The forces involved in a dynamic fall onto a static system is, like Matt said, incredibly high!! There is done testing on that by the likes of DMM and others.

Further on the previous point is to never unload a static system. If you are hoisted up in a totally static system, do not be tempted to stand up on a mast step. If you slip, and then shock-load it, the forces might well brak you and/or the gear.

Be aware that when going aloft, you’re just a “meatbag”. It is the person(s) on the “ground” that have the difficult task. They are the ones that need to know how to operate the ropes and solve any difficulties that arise (like entanglements) without you being able to really see or help them. Worth remembering if you have new people to help you.

Regarding the use of a backup, I am split on that. Personally I rarely use a backup in the sense of two ropes. This is based on the fact that I climb the mast myself (alpine style), and as such, I am the primary safety, and the single rope I use, is the backup. This is also supported by a prior inspection of the ropes and thereby I have a high level of confidence in the gear. I use a short tether to attach myself at the work site.

If I was unable to climb the mast myself (using my own hands and feet), and needed to hang in the rope (through the use of ascenders or someone winching me up), I would be more inclined to use a second rope as backup. However I do consider the backup a potential hazard with the added clutter, and it would be an operational assessment in the situation, for example:

Going up solo using ascenders and with a backup rope means a lot of devices and ropes and slings that can snag or get entangled if it’s moving a lot or very windy. You need 2 extra crew members to tend both lines on deck if you go that approach. And you might not have when that many crew onboard (double handed sailing). The procedure generally becomes a lot more complicated both on deck and up the mast with two ropes.

Getting advice from certain climbers can be valuable. Most take a lot of falls frequently and have seen a lot of gear fail. I would say that many climbers have very valuable input on this. This have indeed been my experience locally with my friends that have done like me, and moved from climbing/alpinism to sailing.

Bottom line is, find a system that works for your fitness level, risk acceptance level, masthead design, and crew composition. And practice it. This is a complex, scary, high-risk activity, that is rarely executed. All the ingredients needed for a bad outcome.

In the end, I’m not sure if my comment ended up being helpful, or not. However I hope it can have a few valuable points.

Arne Mogstad

Hi Matt. Absolutely agree on the fact that the overall strength is the important thing. But as you have said, only use gear designed for it, so no halyard snap shackles and similar. Personally I am familiar with climbing gear and techniques, and as such, prefer to use gear from that discipline. I do however not want to imply it is better.

And I totally agree with what you are saying about climbing/mountaneering gear and techniques. It is indeed favoring dexterity etc! Absolutely worth thinking about, both regarding which gear, and also which techniques/procedures to adopt. In fact, I do not think that the climbing-approach will fit most people, and the technique and system that you outlined in the article, is probably a much better one for most sailors!

I think you are very right in the last point about a dynamic system adding extra risk on its own. For climbing the mast assisted by crew, I think a static system is the best way to go. It will keep the loads low, and the risk of a “fall” is much lower! In case you “fall”, it will be a few centimeters, and merely an inconvenience. A fall in a dynamic system will potentially have higher loads, and a MUCH higher risk of injury during the fall (hitting a spreader for example). This is due to the fact that it will most certainly result in a longer fall. Unless being very attentive, it can easily be a couple meters. Going solo, it is near impossible to use a fully static system.

I think the most important thing is, as I said in my previous comment, that we choose a system that fits us, and to practice it.

Again, great article! And a tough subject to write about! Especially when a bunch of people like me are scrutinizing and picking on it… 🙂 Although, it is not a setup that works on my boat solo, I basically agree with everything you’ve written and would not be hesitant to climb your mast with your setup if I was crewing there!

Kindly, Arne 🙂

Andrew Craig-Bennett

Nice article.
These comments are from an unfit 70 year old with an elderly 55ft cruiser racer:
1. All our halyards are Dyneema or Vectran. Luckily, we have six of them if I count the topping lift. I doubt if many boats have a climbing rope rove in place of a halyard and I would want the same diameter (12mm) if I were to reeve one in place of a halyard as a safety line, to exclude the risk of it jumping the sheave.
2. Our halyard winches are at the mast, and I’d rather stow a hard hat in the locker with the bosun’s chair than lead halyards to sheet winches via snatch blocks. That would be a lash up, and would increase the risk of a mistake. In any case the halyards are not long enough. All tools that go up the mast are on lanyards, by definition!
3. My nice Harken bosun’s chair came with strict instructions to use figures of eight, not bowlines, but I have been tying bowlines for sixty years (my father made me tie them behind my back!) and I have more confidence in a knot that I know thoroughly, than in a new one that I’m still having to think about!

Dick Stevenson

Hi all,
I wrote about the advantages of the Brion Toss harness (a climbing harness with added padding and other features to make it his design for going aloft) in the first AAC part of this going aloft series which I have used for 3 decades now.
One advantage not mentioned (or at least I have not noticed) of a harness over a chair is that the lift point of a harness is at your naval (there are other advantages). This allows masthead work without resort to foot-slings or a pair of steps at the masthead.
My best, Dick Stevenson, s/v Alchemy

Dick Stevenson

Hi Matt and all,
I have been using a Brion Toss harness for 25-30 years and it is still in perfect shape. I have been upside down in it, stretched horizontal and spent much time in it doing various projects over the years. I could not recommend it more highly (as I do his book, The Rigger’s Apprentice). It is not so expensive if amortised over many years and there is great pleasure in using a well designed well constructed piece of gear.
My best, Dick Stevenson, s/v Alchemy

Augustus Wilson

Thanks very much for posting this. One comment about using a snatch block. With that purpose ultimately in mind,years ago, I bought a snatch block with the highest working load I could find. Going up the mast, I had a halyard led through a block at the base of the mast trough the snatch block fastened to a secure anchor point on the foredeck and then to the rope capstan of the anchor windlass. I had a second halyard led to a cabin top winch by the companionway, through a jam cleat and tended by my wife, who knows exactly how to keep that safe. I was not worried about being injured by the windlass hoist. However, I had a friend from another boat whom I thought knew what to do, tail the line and operate the windlass. (Using a competent third person to tail would have been better). All went ok, until somehow the snatch block was twisted and all the load was on the side, and it was dangerously deformed, barely holding the line. I didn’t know this until I was back on deck. The snatch block was from Ronstan, i think, and at the next boat show I brought it and showed it to someone in the Ronstan booth, who said they are not capable of any significant side stress and are not safe to be used for going up the mast. Surprised me…… But I have never used the windlass again for for going up the mast.

Before that I used a friend’s inchworm climbing harness to go up the mast on my then 27 ft boat. I did that several times over several years. Then, after replacing the halyards I went up again with no problem. But even though the halyards were the same diameter, there was some subtle difference and I could not get it to slide properly to allow descent. I had a safely line halyard and soft bosun’s chair, so was able to take the climbing harness off and be lowered by my wife tailing a winch carefully. However, before then there was some humorous discussion with others nearby on the dock about my taking up residence at the masthead……….

Charles Starke MD

Hi All
My son climbed El Capitan seven times, and, in the rescue service, rescued climbers on the side of El Cap and Half Dome by dropping out of a helicopter on a steel wire.
All of the best climbers who were his friends, have since died. I urge all of you to take all these recommendations extremely seriously. The long term statistics are not in your favor. Take every care and precaution.
Best wishes,
Charles L Starke MD FACP
s/v Dawnpiper

Ben Logsdon

As a rock climber, I fully trust a single rope and seat harness. I don’t want to introduce the added complication of a back-up line to an industrial style harness in addition to a bosun chair. If you ever have the opportunity (misfortune) to hang in one, it is nearly unbearable because it is designed solely as a body arrest system. The crew I generally have is one of my rock climbing partners, so I have full confidence in their line management below. If I don’t have crew, I look to other rope-based disciplines for my solo rig: canyoning and arborist’s single rope technique (SRT). Both use rock climbing type gear and are very applicable to climbing a mast. Many hunters also use a similar setup to get into their high tree stands. Having the specialized knowledge (and strength) to use SRT, I’m not sure I could give different advice to the cruiser who occasionally ascends the mast than what you outlined above.

Paulo Sousa

One aspect that I find critical to a hassle-free mast-climbing operation, is good communication with your, non-expert, crew winching you at, sometimes considerable, distance and even inside a dodger. Yelling hard is not the answer. For that, the use of an intercom headset has proven invaluable for us.

Reed Erskine

Not sure if anyone has mentioned this, but my wife and I have always used two-way headset walkie-talkies to communicate between the deck/winch person and the person aloft. We have electric primary winches so my wife can handle the winching, and the ride up is essentially an elevator….but this can be dangerous if any part of the gear or person being lifted gets caught in the rig. Having continuous, hands free communication between the lifter and liftee is a huge plus for safety and convenience, especially when approaching the top of the mast, or critical height adjustments. The only practical headset choice currently on the market is the Eartec Ultralight at $385 a pair. Not cheap, but they work very well, and useful for anchoring and mooring coordination as well.

Eric Klem

Hi Matt,

Thanks for the article. It sounds like the person on deck for you is tending 2 lines. How is this done in practice or are there 2 people on deck? It seems like you would need to constantly be making one off, adjusting the other then swapping at least every foot. This would be >100 trade-offs for a rig like ours which seems like it would take forever and increase risk just by the high cycle count. For this reason, we have the person aloft take care of the safety line by using a short prusik on a taught line so that there is never a chance to fall more than a few inches. This obviously adds the complication that you need to make sure you are rigged so that you could lower a person who became injured (we do use a helmet when the boat is somewhere it could start rolling).

One issue I have run into on several boats is not having 2 halyards available on the same side of the mast. On our own boat, because we are hank-on we always have all halyards ahead of the mast available and usually climb that side. I have seen people flip halyards around the spreaders but this makes me nervous. When pressed, I have re-rigged at each spreader to use a halyard from the other side but this is a pain and introduces room for mistakes.

Do you know the reasoning behind needing a full secondary harness assuming this comes from the standards? Has there been a history of failures and if so, are the causes consistent like wear out failures or something? I typically use a bosun’s chair but occasionally use a search and rescue harness that I have. I have not worn redundant harnesses except when I was working commercially and our chairs were the old school planks with a few pieces of line. If there is a history of failures and they are hard to prevent, then I certainly would understand the need to have a full backup harness.

We look at the masthead with binoculars before climbing but this is mainly to make sure that the climbing line and safety line we have hauled up are lying correctly but we do also look for anything else amiss.

In our case, if my wife is going up, I generally grind her up with a winch but if I am going up and we are not underway, I jumar up. I can get up there quicker and can do it many times, my record is something like 8 times in a single day. Any more than this and I might want a rope walking setup but those seem a bit fiddly for general mast climbing. I have thought about getting a winch bit just for my wife to send me up but it has never been a real issue.


Eric Klem

Hi Matt,

Thanks for the additional information. I can certainly see the argument for just making everything independent (ignoring general rig dependency) and redundant. To me the key in doing that is that you have to have full confidence in both systems. In design, I really try to avoid belt and suspenders almost all the time. I find that the temptation to take a shortcut on the belt or suspenders or both is too high and often that means that if one fails, the other one does or you have no knowledge that you are already on your backup so you often don’t gain anything besides complications and sometimes actually lower reliability. My exception to this is where you have wear or other hard to predict/monitor failure modes and I do think that there are some present here. It is relatively straight forward because you can feel what you are hanging from but you do need to really consider everything a primary system and not say “that is only the safety and won’t really get used” as the safety is actually more likely to be shock loaded.


Alastair Currie

I inspect drilling derricks and trained to use industrial safety harnesses and lanyards. They are designed primarily to be used with two safety lanyards, when working at height using three point contact through feet, hands and always one lanyard. The attachment point is at the back. If you fall, the attached lanyard will reduce the loads to avoid trauma. There are various styles of fail safe lanyards and styles depending on the job. The other way they are designed to be used is by being attached to either an inertia reel or a self retracting lanyard (SRL). If you fall the inertia real simply resists acceleration and maintains a low velocity; the SRL acts like a seatbelt and stops extending when loaded. The key point here, is that there is only ever one device to stop me being injured if I fall. I believe what is being proposed, bosuns chair or belt, plus safety harness, and double halyards, two sets of controlled lifting processes is too complex and that introduces increased probability of an event whether climbing or in an emergency. The simpler systems are easier, less complex.

I use a bosuns chair and any halyard that does not rely on a swivel block. I use a round turn and two half hitches, with the tail bound with electrical tape. This maximises the hoist height. My son berates me as he uses the figure of eight being a climber and trained, plus he is tall with very long arms. I am short.

All my halyards and winches are at the mast and all except the topping lift, pass through clutches. My partner will tail outside the drop zone and I climb, no winching required. I use grippy shoes on the mast, and the shrouds, when they close in. It sounds harder but with my partner tailing, every inch is easy as I don’t have to support my weight the whole time, and it gets easier to climb as I go higher. I do stop and rest at the spreaders as I am fatter and less fit. When being lowered I keep myself on the opposite side of the mast from my partner.

Tools are tethered and placed into a bucket, with the tethers tied to the handle, which I haul up, the bucket lanyard being attached to the bosuns chair and long enough to go from deck to masthead.

Before I go up everything, except the truck sheave, is inspected, including the halyard over its length (the bucket lanyard allows this). I have a rigging company inspect my mast every second year, hence the sheave condition is not quite a guess.

I think, an inertia real would be a good safety feature for single handing and in a remote area. It would be hoisted on a spare halyard, with a light line to retrieve the line with carabiner. Clip it to the bosuns chair or climbing harness, then get hoisted on another halyard. The inertia real will self retract. If the halyard failed the inertia real will allow a slow descent. Similarly if the halyard jammed, release yourself from the Jammed halyard, easy with a round turn and two half hitches, then let the inertia reel do the work.

Finally, the safest job is the one you don’t do. If accessible, go to the marina or harbour wall and use a telescoping access basket from the dock side.

William Murdoch

Alister Currie said, “I use a bosuns chair and any halyard that does not rely on a swivel block.”

I have beside me as I type two Schaefer Series 7 swivel blocks that have failed because the rivet in the swivel connection broke. One was the mast base turning block for my mainsheet where it broke during an unintended gybe. I had temporarily used that same block as the turning block at the mast base to lead the main halyard to a genoa winch for my wife to raise me up the mast. I sent photos of the two broken blocks to Schaefer.

Broken Blocks.jpg
Cliff Schubert

In researching mast climbing, I read lots about avoiding swivel blocks at the top of the mast and how they can fail. However, this is probably the first time I’ve seen it mentioned to consider the mast base turning blocks.
For boats that have halyards led back to the cockpit winches, its not mentioned enough the need to consider all those failure points along the way.
I have mast base turning blocks for my genoa halyard. When I use the halyard as a backup in my ascending setup, I use a locking carabiner to either bypass or back up the block.

Mark Buss

i plan on using ATN Mastclimber next trip up the mast. Allows you to stand up to reach over the top of the mast when you’re up.
Has redundant ascender mechanism, comes with a bosun chair and I would use a second spinnaker halyard for the fall protection backup. Deck crew only needs to manage the safety line.

John Harries

Hi All,

I have been following along here and the thing that’s really jumped out at me is that most of the comments are along the lines of “I do it this way and think that’s the best” (the last part implied).

However, to me, the best use of Matt’s article is:

Here’s a professional engineer with proper trained in fall protection construction worker who has applied that knowledge and training to boat mast climbing with an open mind and no preconceptions.

So I’m going to measure what I do, which if you are anything like me, is based on hearsay in the sailing community, claims of people trying to sell me gear, no formal training, and my own habits that may be terrible, against Matt’s article and actively look for what I might be doing wrong.

That will be the thrust of Part 2

William Koppe


We applied large 4 lease letters 6 ft high to a glass facade in Sydney CBD on a Sunday using the building window washing cradle. On Tuesday morning that cradle made the front page with 1 window washer plastered on the pavement and the other holding on to a vertical cradle held by only 1 wire.My crew was not happy. Turns out battery acid had corroded the failed wire.
We then moved to separate safety lines of 11mm climbing rope and ASAP to harness for each worker.
We used the electric anchor winch on Delta Wing with main halyard led throuch Harken snatch block and a fixed and tensioned climbing rope with ASAP for a safety line. Worked well. Used same system on Pacha with 72 ft mast.
In addition used a short harness strap around mast to stop swaying away from mast which was taken several times around the mast when working at the top.This short strop also limits the fall to the next spreader and by looping around the mast twice would slow any fall by friction/tension.
Finally in selecting electric winches for Tanielle I came across several horror tales of runaway winches usually caused by sticky controls. There was even one case of someone being winched through the masthead turning block and killed.
That is why I would prefer 3 turns only on the winch with the tail person keeping enough pressure on the line to give grip.
With a 90 ft mast and lots of electric winches it is practical to simply press the button and up you go.

Mark Wilson

I have been reading each comment as it comes in. I have always found going up the mast unpleasant. I hadn’t realised quite how dangerous it could be. I was always worried by it; now I’m thoroughly frightened. My main takeaway from this is: if I am in harbour and need to go up the mast I will pay someone else to go up. Maybe I can offset the money spent on this by painting the bottom of the boat myself – another joyless exercise.

Now on to the big question to be covered by John in part 2. Going up at sea short or singlehanded. I know what has worked for me in the past. Also unpleasant and with several drawbacks.


PS. My attitude has been further coloured recently by a medical diagnosis of vertigo. I had thought vertigo meant fear of heights but apparently not.

John Harries

Hi Mark,

That’s a very sane analysis, although another way to look at it is that if we go cruising sooner or later we will need to go up and therefore it’s better to practice that regularly, which is the school of thought I subscribe to, although I can totally sympathize with your thinking. Of course your vertigo changes all of that.

As to going up at sea and short handed, I’m going to cover that, but I’m afraid I don’t have any magic bullets to make it easy and safe.

Tom Borgstrom

Thanks for exploring this topic; it was one of the first questions I posted when I joined AAC a couple of years ago.

While I appreciate the risk of climbing the mast and have a healthy fear of going aloft myself, in all my years of sailing I have never heard a story of somebody falling or being injured when working up the mast.

Are there any statistics, or even anecdotes, of mast-climbing incidents and the failure mechanisms involved? I gain a lot from reading sailboat incident reports (like the recent one that lead me to reconsider my upwind reefing approach), but so far I don’t recall seeing anything like this for mast-climbing incidents.

John Harries

Hi Tom,

I know of two different mast climbing fatalities and a maiming.

That said, as is pretty much always the case in offshore sailing, I don’t think there are any reliable stats on mast climbing accidents given that there is no accident reporting requirement and even if an accident is reported there is no aggregation system that I know of.

Therefore I think we need to rely on logic to personally assess risk, just as we need to for pretty much everything else around offshore sailing. To me anyway, a bunch of mostly totally untrained people being hauled up masts on uncertified gear is intrinsically dangerous.

Dick Stevenson

Hi all,
I may have missed this, but the location of going aloft should be considered.
I would appreciate thoughts on going aloft on the hard. Is it generally considered that hard stands/cradle etc. that can tolerate the winds of a winter storage is acceptable stability to go aloft. And some marinas do not allow going aloft.
I try to go aloft in a marina, but often I ended up being at anchor or at a mooring (some or all of the following apply to going aloft at sea). Depending on the company I notice around me, I sometimes wear a helmet (climbing). When a wake/wave is noticed I do not rely on the strap around the mast to keep me from banging around: I hug that mast as if trying to mate.
On the subject of helmets, the few times I have been caught out and surprised, I have thought that a football helmet would be wise to protect the face. Climbing helmets protect from above and the worst that can come from above when up the mast is produced by birds. However, it is a very real possibility to get slammed into the mast face first: holding on once or twice has taken all my strength: even with a strap, it allows at least a few inches of movement and the momentum that can development in those few inches can be impressive and do face/head damage.
 Random thoughts, Dick Stevenson, s/v Alchemy     

Matt Molkoski

The first time i went up the mast was in a bosuns chair, with the main halyard and the spin halyard as a safety.

Since then, I’ve switched to a rock climbing harness. I run a dedicated climbing line (with a sewn eye rated to 22kN hooked into the screw shackle of the main halyard.. curious thoughts on this practice) and have both mechanical ascenders, or prussiks depending on the day. Then the spin halyard is attached to the harness as the safety line.

To lower, we just lower the main halyard, and the ascenders or prussiks stay in place. I’m fairly young and fit, and it works better than having someone else try to winch my 200lbs up the mast.

Matt Molkoski

Great comments on the spinnaker halyard.

Thankfully on our CS30 the spinnaker halyard is run through the mast, the same as the main and Genoa halyards, to the top of the mast and we don’t have to worry about it running through a swivel block.

Appreciate the feedback on the screw shackle. I will definitely make sure to check how we have it tightened next time!

Dick Stevenson

Hi Matt,
I have found that using halyards that emerge straight out of the masthead and go various side  directions are prone to chafe: for me it was using the spare halyard for a topping lift on my whisker pole. The use of a fully articulating block after the halyard leaves the masthead sheave makes chafe very unlikely.
My best, Dick Stevenson, s/v Alchemy

Bill Harju

Great advice! All the same gear I use! I’m a safety guy for a marine construction company. I get to borrow a harness for now. I’ll buy one before I sail off into the wild blue yonder

Drew Frye

Climbing always generates comments, and there is lots of good information here. A few thoughts, from perhaps the longest term and most active climber on the thread (40 years of rock and ice. all over the country).

Harnesses. There is nothing wrong with a seat harness if you have hips and no beer gut. The harness must be snugged above the hips in such a way that it is unimaginable that it could be pulled down in a head first fall. And I have watched climbers fall in every way. If you don’t have distinct hips, a full body harness is required.

A fall arrest harness and a harness for working at height are not he same thing. For example, the illustrated harness would put your legs dangerously to sleep if used without a chair, because of the way it presses on the femoral artery (read up on suspension trauma). It is more convenient to use either a tower harness or a big wall harness, which feature more padding and better leg loop design. I use a seat harness with additional loop padding, much like a tower harness.

Winches. I know of several fatalities that were caused by momentary slack (one was on the Appledore), which allowed the turns to come off the winch. Splat. They are NOT as idiot proof as a climbing belay devise and I would be uncomfortable using that as a soul belay. I would have a passive fall arrest device (see below) on another line. In fact, this is required and often see with pro riggers.

Fall arrestors. The author seems unfamiliar with trailing auto belay devises like the Petzel ASAP, Camp Goblin, or many industrial variants. I use these rock climbing and up the mast. On a mast they can be used without the tether because you are following the safety line, eliminating the fall distance and the need for a frangible tether. Additionally, you need to take a HARD fall (over 700 pounds in most cases) to trigger the rip stitching in the tether.

Never use a bowline to tie in. The climbers you know will all walk the other way. This has been poor practice for 50 years at least. Even with a back up knot it is not the best way. Figure 8.

Finally, safe climbing involves NOT falling. The climber should be able to focus on his hands, feet, and movement, not frigging with the knitting. I have fallen perhaps a thousand times, but never climbing something as straight forward as a mast. I concentrate on smooth, solid movements. I secure myself at the top.

John Harries

Hi Drew,

Thanks for the comments, very useful. I will leave it to Matt to discuss the industrial fall arrest harness.

On the bowline figure eight debate. I know many climbers piss all over the bowline but I have yet to hear a reason, other than “we don’t do it that way”. I have been using bowlines for 60 years (since boy scouts) and have yet to see one fail. Don’t get me wrong, I’m not saying you are wrong, just that for me to really get on board with the idea that bowlines are no good I need to hear solid reasons so as to make sure this is not just a meme in the climbing community or alternatively that there are reasons in rock climbing not to use them that don’t apply in mast climbing.

To me the the big benefit of bowlines is that we sailors tie them every day. Not so the follow through figure 8, so I need to hear a reason the the latter is better than the former and that reason has to be good enough to outweigh the safety of tying a knot you use every day.

Stein Varjord

Hi John,
I also use the bowline, and have for decades. I never tie it wrong, as it’s thoroughly embedded as an automatic motion, plus I still always check that it is actually done right. My conclusion is that the bowline is safe, for me, and probably for the majority of the very experienced people here.

However, Drews comment made me search for reasons why I might be wrong. I found two possible flaws with my above conclusion.

1. The bowline is a smaller knot with sharper bends and less surface friction than a double figure eight. Does that weaken the rope slightly more? I don’t know, but it’s possible.

2. I see people tie a faulty bowline, without realising it, at least once a week. The double figure eight is more hassle, but if done wrong, it’s visually obvious, and it still works. It’s fault correcting and fault tolerant. The bowline is arguably neither. The fault modality is the worst possible. One flaw – you fall.

To me, point 2 is enough to make me change my mind. While the bowline is safe for me, it’s not a safe knot for climbing in general, thus also not for the average sailor.

I think there might be value in having a specific knot that is used for this task only, to make it clear that there are unusual risks at play, reminding us that other precautions must also be taken.

I’d guess that the percentage of unskilled and uninformed people participating in rock climbing etc is far lower than ditto in mast climbing, also on boats run by highly skilled sailors. I think the less experienced need to see and learn a systemic approach to climbing the mast. A fault tolerant system. I should not do what I don’t recommend for others.

Stein Varjord

One more problem with the bowline: When it’s done wrong, it usually looks like a knot and will often hold for a while. I’ve seen many boats tied up for days with only faulty bowlines, and one untouched for two months, in protected harbours. It fails with more load, of course.

I can reliably spot a correct or faulty bowline with a quick glance. When I teach that knot to others, I show the right and the wrong version next to each other. If the wrong one is dressed well, a significant percentage of coastal cruisers etc cannot reliably pick the right one. This problem often remains even after they have known and used the knot for some time. Some never learn to see it reliably.

Normally a faulty bowline knot will slip under light load, but not always. It depends on how the flaw was made, and rough surface thicker ropes can hold, especially with a long tail. It’s possible to be hoisted up the mast on a faulty bowline knot, which suddenly releases when the climber changes position.

My conlusion:
Since many struggle with detecting a faulty bowline, and it can hold until high in the mast, the bowline in climbing is a dangerous trap for the average sailor.
Red flag! I’ll use the double figure eight from now on.

As a lifelong sailing fanatic, getting my boating related opinions challenged like this, only happens here, with the amazing AAC. I love discovering that I’ve been wrong, since it means I got better! Thanks!

Glenn Pullen

I use a figure 8 because I have never had one come undone, no matter what I did all day climbing. And it works in stiff ropes, or frozen ropes. A bowline can also be snugged up of course, but I just do not trust it as much as the follow through figure 8. And my eye just sees that it’s tied correctly. Same is true for a bowline though. So I guess it comes down to a security thing.

Rob Gill

A quick search for stress failure caused by different knots, in different ropes, revealed this study:

It documents that indeed a correctly tied and dressed figure-8 knot fails at a higher % of the rope breaking strain (BS) than the simple bowline, across all the rope types tested. If you are expecting falls as an integral part of your sport or profession, then this would be comforting I would imagine.

Like Stein, I believe (but don’t know for sure) this delta in % of BS will be because the rope radiuses are greater for a double figure-8 knot, than for the single line bowline. Also the double figure-8 knot will probably tighten evenly when the load comes on, but possibly unevenly with the bowline.

This made me wonder if the bowline tied on the bight, correctly dressed with its larger radius bends (having two ropes inside each bend rather than one), would out perform a single line bowline? Unfortunately the test results don’t provide answers here.

To bypass the halyard shackle, I admit to tying the bowline on the bight through the bosun’s chair, and so wonder if there would be a significant difference in the % BS performance between the double figure-8 (tied using the climber’s follow-through method), and a bowline tied on the bight if both are properly formed and dressed?

Must agree with John though, all sailors should be able to tie a proper bowline, even on the bight, and if they can’t they probably have no business going up a mast. And certainly not supervising others doing so.

John Harries

Hi Rob,

Thanks for the link. very useful.

The take away for me is that the strength reduction for a bowline, while significant, may not be enough to justify learning and practicing a new knot that we will only tie a couple of times a year, if we are already 100% reliable tying a bowline and the halyard in question has enough safety margin to accommodate the strength reduction of the knot we know.

Rob Gill

Hi John,

On reflection, I agree the bowline (on the bight for me) is a solid knot for the bosun’s chair with its static loads, but the doubled figure-8 knot is better for the safety harness, which can experience dynamic loading.

We use the figure-8 as a stopper knot (sometimes with an extra turn around the standing part) so for me, the doubled figure-8 knot is no more complicated than achieving a well dressed bowline on the bight.

Best of both worlds?

John Harries

Hi Rob,

As I say in part 2, everyone should use the knot they are most confident in and if that’s a figure eight that’s fine with me. My only concern is when climbers try and jam their best practices down our throats without being able to show how that applies to us sailors. And so far I have head nothing conclusive that convinces me that a bowline is unsafe in this application.

Drew Frye

There are a number of reasons, not all of them applicable to mast climbing. But best practice is best practice.

  • A bowline can be tied incorrectly and is harder to quickly check by sight. Remember that just one mistake and you are permanently dead, and that in the mountains you may be tying the knot wearing mittens, in the dark, dead tired, and under duress. It is idiot proof, and we can all be idiots once.
  • The UIAA drop test standard is based on using a figure 8. No other kind of knot, not a splice, not a wrap.
  • The figure 8 is slightly stronger than a bowline when tied in climbing rope.
  • The figure eight absorbs a significant amount of energy when tightening in a severe fall. Important if you fall right off a second pitch belay (a ledge) with just a few feet of rope out and no intermediate belays. A fall factor 2 direct against the belay. Standard practice is to place a redirect anchor just above the belay itself, but everything helps. This is the most severe fall in climbing, much like the UIAA test. The 50-foot whippers you see on YouTube are much less severe in terms of forces. Not applicable to mast climbing since there is no actuall fall involved. (Climbers do not consider falling against a tight line with virtually no slack to be a fall, in terms of forces, wear, or energy. More like a casual slip, often taken a dozen times in quick succession while practicing something difficult.)

Yes, a figure 8 can be impossible to untie after a serious fall. In fact, that is one of the ways you judge if the fall was serious enough to damamge rear. If you can untie the knot with your fingers it wasn’t bad in terms of forces. A bowline gives no such indication.

Climbers tie figure 8s multiple times every day. In the dark, in the snow, no problem. In fact, most are familiar with at least 2-3 variations for special purposes. Bowlines a a little less often, but still every day.

No, a bowline is not deadly and climbers do use them. It’s just not best practice. No reason to fight it.

John Harries

Hi Drew,

Good to hear there is nothing intrinsically wrong with a bowline in the climbing world.

That said, I’m sure you are right that the figure 8 is best practice in climbing, but I think you, like most climbers are missing a key point here: we sailors don’t tie follow through figure 8s every day. I think this is an important factor in safety that should not be ignored. And with halyards, particularly on bigger boats, the shackle will often not fit through the D ring on the chair or harness, so there’s the added complication of tying the knot doubled over.

Don’t get me wrong, I will take some time to learn a follow through figure 8 and may easily change over to that (I love learning new things), but I think we are wrong to jam that idea down peoples throats since I still think it’s safer to use a knot you use every day, rather than a knot you use say twice a year, and particularly with my hack of fastening the shackle to the loop on the bowline.

Also, in my view, in our application not being able to untie the knot after a fall is not a feature, but a bug. This also means that the figure 8 has no uses on a boat where most knots will take high loads, so reinforces the fact that we won’t tie on often.

Dick Stevenson

Hi all,
In all this talk of knots, it renewed my interest (and confusion) about the “right” way to tie a bowline. The methods (as I understand it) are having the free end “outside” the loop (wrong) and having the free end inside the loop (right). Now the “inside the loop” variation has always just looked right to me, but the only knock on the “faulty” bowline I can discern is: with the free end dangling outside the loop, it might end up being hung up on things (such as the sheet being tied to the clew and getting hung up on a shroud). The “correct” bowline would more smoothly travel over and around things.
But I am at a loss as to why the integrity of the “outside the loop” bowline knot is so compromised that it is deemed faulty. It looks like it should hold just fine, but some reading I have done seems to say otherwise without explaining the failure.
Thanks for your thoughts, My best, Dick Stevenson, s/v Alchemy

John Harries

Hi Dick,

I’m with you on this. In fact I have to admit that I tied my bowlines outside tail for some 55 years without issues until Eric Klem pointed out that inside tail was less likely to snag.

That said, the only way I have seen a bowline fail from being tied wrong is when the fox goes though the hole the wrong way. And in that case the knot falls apart in your hand before you can use it, so I really can’t see how a bowline can be tied and pulled tight, and then fail.

Frankly, at least to me, all this about bowlines not being safe is much ado about nothing and distracting us from much more important safety issues around mast climbing.

Eric Klem

Hi Drew,

If the Appledore incident you are referring to is the one on Appledore II out of Camden, Maine that happened at her winter berth in Key West about a decade ago, I don’t think it applies very well although your broader point on winches stands. I know the boat pretty well and the person would have been belayed off a belaying pin with the line direct to the underside of the pin and not a winch, they don’t have any (I heard about the accident through the grapevine but never saw a report or anything so please correct if you know it to be wrong). Belaying pins are very tricky with light loads. I can’t remember the exact size but I would guess that the halyards are 5/8″ 3 strand nylon going around a 1-1.5″ diameter pin. On some of the bigger boats, the halyards would be 1″ and the pins maybe 1.5″-2″ which was way worse. The line’s inherent stiffness means it wants to ride off the pin on its last turn and at light load there is usually only a single turn which wants to jump off on you. On smaller boats like Appledore, there are not deck level turning blocks so gravity is also working against you if there is slack as the first turn goes under the pin and if it pops off, a whole bunch of slack just got introduced so you will never get it under control. Of the people I was involved in letting go from boats for safety reasons, in all cases ability to handle a line on a belaying pin safely was a big part of it.

When I started working on these sorts of boats, pretty much everything in going aloft was single fault to the point where climbing aloft was done without a harness mostly. A not insignificant portion of the reason for this is that big gaffers typically grease (slush) their masts and it makes anything that touches the mast disgusting and too slick to handle so you typically just went aloft on a gantline made of an old halyard you would rig and that line would be permanently disgusting. The scariest part was actually that without winches if you went on a gantline and not a halyard which had a block and tackle, you would climb the ratlines then get in the bosun’s chair aloft with no safety as it wasn’t practical to haul you up with no mechanical advantage. While I was working on these sorts of boats, there were a couple of deadly falls and people started to get more serious. The typical backup that I saw on a bosun’s chair was a prusik from the chair to the part of the halyard going up the mast. While this did not provide the redundancy that Matt describes, the gear on those boats was massive and they were effectively proof tested at much higher loads regularly so it was a bit of a different calculation. I hope the safety standards have improved from when I stopped working on those boats.

All that being said, it does take some skill to belay on a winch. The number of turns is critical to hit the sweet spot where you have enough turns to arrest a fall but not enough that you get an override.

Securing yourself at the top is an interesting question in my mind. What you give up is the ability for someone below to lower you. I have actually climbed aloft to unclip and lower a person who had a major pinch injury involving a wire block that rendered them unable to unclip and get down. That was a specific big boat type of accident but I could see someone smashing their head into the mast with a big wake or something. That being said, you are much more likely to have this sort of injury if you have not tied in locally. I guess I don’t know what is best.


Drew Frye

Yes, probably the same incident. As I recall the climber had unweighted the seat by climbing out on a spar, which supports your conclusions. I think the report said winch, but it was certainly wrong (I sailed on the boat once, and there were no winches). But same idea, same warning.

The point is that winches and belaying pins are shaky as belays because they can fail if there is slack, which commonly occurs in a fall. In fact, if there is a fall there is always a moment of slack. Climbing belay devices are immune to this failure, as they must be. Many times I have been lifted off a belay ledge, secured only by my anchor tether (which was quite stout). As long as you keep your hand on the rope tail, all is good.

From my reading, the most common failure climbing the mast are belay errors and pulley failures, followed by people using snap shackles. The same is true in climbing; belay errors are too common. It seems easier than it is, because when things go wrong it happens fast. I was dropped about 20 feet once by an inexperienced climber that dropped the rope. Fortunately, I landed in sloping gravel without harm.

John Harries

Hi Matt,

Some good points, but I’m not at all convinced that having a line around the mast from hip to hip adds a lot of safety or would allow a safe decent in the event of a winching screw up.

I have climbed poles with a hip strap (in the army, sort of (Bermuda Regiment) long story) but that was with climbing spikes on. I just can’t see a climbing mechanism that makes this work without spikes, and nor can I see it working in a sudden hoisting halyard failure situation where one second we are sitting in a chair being hauled up and the next the chair is gone from under us.

I’m also not much liking the idea of one crew tending both halyards in this set up since as soon as we have even a foot of slack we are getting into some pretty strong arrest loads. I guess that might be OK on a Dacron halyard (don’t know) but I’m pretty certain that a fall of a foot on HM halyard would really sting and might even maim. Also, surely having someone grind the winch a foot, then cleat off, uncleat the safety, grind a foot, repeat, is excruciatingly slow? Assuming 30 seconds a cycle that would be 25 minutes to go up a 50 foot mast?

Drew Frye

You bring up a good point:
“I am very reluctant to recommend harnesses without an upper body component unless you get equipment-specific training and a proper fit check by an expert when purchasing them. Properly fitted, some of them can be very good, but they’re not as forgiving of imperfections in fit (or of being worn over foul-weather clothing) as full-body ones.”

I just returned from a morning of ice (waterfall) climbing. As a rule, even frozen falls drip, and sometimes just plain pour right in your chest (ice screws that penitrate through to running water) a whole lot, and so your clothing must be suited for rain in a tmperature ranging from -10 to 35F. Lots of Goretex. Sometimes waterproof soft shells. But, unlike sailing gear, which is fitted rather loose, with a coat with a long tail, with climbing gear everything is tailored with interaction with the harness waist belt in mind. Jacket must be thin, tailored, and capable of being tucked under the belt without interference. Or it might end short of the belt, but it cannot interfere with access to the belt, since your gear is clipped there. And no one has a gut.

Foul weather gear, to be certain and very carefully selected for the purpose, but very different from sailing clothing.

I’ve never climbing a mast in foul weather gear, and if I did, it would be fitted, layered, and light. Most likely I would wear my drysuit; it is quite fitted and there is nothing to snag. But I’d rather get wet than fiddle with the bulk of traditional foul weather gear. I think the real take away may be that you do NOT climb in heavy foul weather gear, no matter the weather. The clothing cannot be allowed to pad away away body structures and preclude a good fit. The same problem extendes to PFDs and relates to some of the accidents where PFDs have slipped off. But that is a different conversation that has been covered elsewhere. None the less, this is something that sailors should be aware of; don’t let you clothing turn you into a puff ball that safety gear cannot fit and secure.

John Harries

Hi Drew,

Good point that I had never really thought about. Now you bring it up (thanks) I’m with you on the fundamental here: don’t go up in foul weather gear.

As an aside, at first I wondered about pro bowmen on race boats and what they did, but then I realized that these days most of them are wearing dry suits, just as you suggested.

I will work that into the next article.

Drew Frye

About industrial fall arrest harnesses. This is case of gear designed for something different. The dorsal attachment point protects and industrial worker on a scaffold from falling backwards and hitting his head. No such risk on the mast. In stead, it forces a forward fall, face into the mast (or rock if you are a climber–imagine how fun that is). Tower and rigger harnesses always have front attachment points, and these are the ones you use.

A dorsal (back) attachment is all wrong for climbing the mast. It is also what leads to suspension trauma.

My advise, if you want to spend on a chair and a harness, is to buy a low-end tower or arborist harness, which can be had for $120-170, and skip the traditional chair and separate harness. That is what pros do. There are more expensive, more rugged harness, but these are designed to last a decade of rough, daily use. You don’t need that.