Going Up The Mast—Four Dangerous But Common Mistakes

How many dangerous mistakes can you spot? For extra points (and better personal safety) how many of them have you made?

Before we get going, if you have not done so, Please read the first two parts (Table of Contents at the bottom of this article), otherwise this article will make no sense to you.

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Jim Schulz

Whether or not it has any safety benefit sometimes tying off can be helpful for comfort or ergonomics can’t it? As in it can be hard to get positioned comfortably at the masthead when the highest you can get your tie in point is a halyard sheave. Here’s a product I’ve found useful climbing, because it makes it easy to control slack in your anchor system. Useful in this case?


Alex Borodin

FWIW, Connect Adjust is standard issue gear at Bavarian Mountain SAR. I like it a lot.

Alex Borodin

Hi John,
I think it’s not fair to say that your backup is completely useless until fully stretched and extended. Both rope stretch and screamer extension absorb energy and thus reduce the amount of “ouch!” in case you do crater.

Drew Frye

Do not use a long extension lanyard on the ASAP or any other device. This creates fall distance and there is no need. Instead, for shock absorption, use an arrest line with sufficient stretch, hauling up a climbing line if need be. I have probably taken 30 rock climbing falls on a Goblin with no lanyard (the Goblin is certified with no lanyard and dynamic or semi-static rope–I think the ASAP may require a very short lanyard), and none of these was at all jarring. I use a short lanyard once, and within moments it was obvious what a mistake this was. I clip it directly to the harness, reducing the fall distance to about 2 feet plus stretch. Do not use static rope for the arrest line; this is just not good practice and using a screamer will not make it so.

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Industrial practice is different. Often a long lanyard is used to get the climbing rope out of your way, perhaps behind you, for easier work. They may be using tools that would cut the rope in a blink. The use of long lanyards for convenience (which you do not need) is the reason shock absorbers are needed. And for this reason, long lanyards and shock absorbers are vertually never used in climbing. Long lanyards should only be used for positioning (preventing swing) and should never be slack.

Do not tension the arrest line directly to the deck. Instead, tension it with a bungee cord (I recommend a very heavy duty bungee, such a long Davis Shockle or something of similar construction). This will allow you to move out on the spreaders. On rock, the common tensioning method is to coil up the excess rope and let it hang a few feet above the ground; the weight of the coil is enough to ensure the device feeds well and you are free to follow a slightly meandering line up the cliff (or by extension, out the spreader). The route up a cliff is seldom straight.

Climbers tie-off all the time, but they follow the “no slack” and “don’t climb above the tie-off” rules religiously. The tie-off is used on the mast to reduce swing from wakes and such, and is not something you climb around using, at all.

Drew Frye

The zero-stretch concern goes away if the halyard is polyester, at the length in question, it becomes semi-static. At the very least, the longest lanyard should be a short screamer. Anything more and you are adding complication.

Using a bungee to hold the device up is fine. Many rope climbing (Google “rope walking”) systems use something similar. More knitting to get tangled in, and it will make climbing more awkward (making falling more likely?) if using any system other than a bosun’s chair, but it will shorten the fall.

I have been around falls where a lanyard was used with a static anchor point. It is a method that will keep you alive, but the victim is generally injured by the impact and the harness and related equipment is often damaged. It will keep you alive, but if you read industrial rescue standards, static ropes are not recommended for fall arrest. Semi-static lines are generally used for this purpose.

I doubt you will find a climber or industrial user that does not use tie-offs for work in situations where sway is a problem. Positioning lanyards are made for this purpose and meet OSHA and UN standards. Petzl sell them. Many variations, some of which are adjustable. You either find them handy or not, but they are accepted by OSHA and EN.

I am adamant because I have spent many thousands of hours up in the air, in both industrial and recreational settings. I have used the system you describe, other fall arrest devices, and settled on what I described above. I have nothing against the ASAP. It’s good hardware.

I am not imposing climbing standards in place of industrial standards. Nothing I said did not meet OSHA and EN requirements. You are right, in that OSHA standards are designed around the lowest common denominator and must fit every possible use and mis-use situation.

I like the final image, with the ascender at the perfect lever-off angle. The chance of failure on that is really quite high, since it has happened a good many times (ascender coming off rope when Jumaring an angled line). With the leg around the shroud, this will be a semi-inverted fall if the suspension line or belay fails. If the arrest line is static, even with the screamer, this is going to hurt and back injury is possible. Some of the nastiest climbing falls involve leaders that get a leg wrapped around the lead rope (head first), so savy climbers are constantly watching out for leg-trapping hazards.

Great articles! This is very difficult topic.

Drew Frye

Obviously, the user should read the technical manuals on all equipment. There are too many ways to use every piece of equipment incorrectly to quickly list. Some are obvious, but some much less so. The trickiest are often those that relate to how equipment can get twisted around in use.

One of the more important specs is rope type and diameter. It must be the correct diameter (10-11 for the Goblin, 9-13 for the ASAP). It must be firm enough and it must be semi-static or energy absorption must be provided. It must have a cover with the correct friction characteristics (nylon or polyester–not Dyneema/Dyneema or Dyneema single braid, and I do not know about Dyneema/Technora blend covers). The risks of pulling the cover off covered Dyneema must be considered in the smaller sizes, since the cover alone of a 9mm Dyneema/polyester rope will not hold a severe fall and the slippage risk has not been researched to my knowledge. I’ve seen jammers strip covers.

The wide range in acceptable rope diameters and types is one of the strengths of the ASAP. The ASAP also tracks more easily up and down the rope if pulled at an angle. The disadvantages of the ASAP are bulk and greater vulnerability to fouling with grit and salt. Both should be periodically rinsed with freshwater if contamination is suspected. The Goblin can be locked in place, like an ascender; this is only an option on the ASAP Lock.

Overall, I would recommend the ASAP for mast climbing. The Goblin is safe, more compact, and perhaps more forgiving of certain environmental factors, but the line size is a difficult limitation for many. I my case, climbing ropes are a good fit for use at the crag, and on the boat I pull up a climbing rope if the halyards are not suitable.


Safety is mostly a matter of checking each critical part of the system. Are both halyards very good? If not, pull in a climbing line. Masthead blocks require some faith, but that is also why you use two lines. Is the harness safe (good condition, cannot come off inverted–yes, I saw this happen climbing–it was fatal). If not, fix it. Is the tie in safe (you covered this)? Is the belay safe (many precautions about using a winch as a belay, mostly relating to the turns jumping off–also jammer tie-off comment was smart–I typically use jammer-winch-hitch on both)? Each of these must be 100% correct or you do not climb. Then you can relax climbing and focus on safe movement and the work at hand.

Drew Frye

One last comment on safety and accidents I have witnessed or am intimately familiar with.

None were related to equipment failures. One bad tie-in knot (bowline tied wrong… we believe). One harness came off (buckle not doubled back because it was too small–was still on the rope, 200 feet in the air). Two belay errors (inattentive or poorly trained– dropped ~ 50 feet but lived).

Climbing is not dangerous, but you need to be meticulous in set-up and belaying.

Maciek Sarnowicz

Thanks for the great article and this good discussion here in the comments. I’m just trying to clarify what I think you are saying. Caveat: I’m not a climber so I don’t know how to translate “semi-static rope” to sailor-speak. I guess that’s the crux of Drew’s comment.

Anyway, I think you are saying that for devices like ASAP or Goblin, the best is to purchase a recommended climbing rope for the device selected, instead of trying to somehow find a match in marine ropes. Then hoist it up with a spare (backup) halyard and secure it to the deck. Is that correct? Of course, then there is a question of how you tie the climbing rope to the halyard. I’ve seen double-figure-eight recommended for such a thing, but I am sure you know more about this than I do.

Dick Stevenson

Hi John (and all)
I like the idea of a “drag” line pulling the ASAP up after you and looking at the picture, I worried about one aspect of this:
If the pull is directly in line, then all should be well. But the pull line might drag the ASAP up at an angle to the line it is attached to. Some of these devises load their line at an angle and then twist around to their “securing” position. In a fall, if the ASAP loaded up when at an angle to the its line, it seems that the securing safety line might “squeeze” out of the ASAP’s jaws. (sort of like a pinched snatch block might release an out-of-line loaded sheet).
I tend to push my ASAP up ahead of me by hand which does not seem to be a problem as I am largely just a passenger when going up. This gives me the least fall distance as that pretty much stretches out the connecting line.
My best, Dick Stevenson, s/v Alchemy

Drew Frye

Gotta share this video.

Because the ASAP depends on the SPEED of the fall and the RPM of the wheel, it seems that keeping the ASAP high with a bungee may not help. It seems that if you use a short lanyard, the fall speed r3equired to trigger the lock results in similar lockup delay. I was surprised.

Not sayin’ just sharing.

I have not played with the ASAP a lot, so I would rather not comment on the details. The Goblin, and most industal fall arrest devices, are based on weighting/unweighting rather than fall speed (they lock as soon as the tether is not holding them up, no movement required), which makes them immune to this problem, but more likely to lock up if pulled at an angle. It also makes them much more sensative to rope size. Compromises.

This is not a jab. The ASAP is considered the best.

Dick Stevenson

Hi John,
Sobering video. It is so easy to make such a simple error with such dire potential consequences.
I do not help my windlass raise me so holding the ASAP out ahead is not a problem, but your point about offshore is well taken. And. It is always nice to have hands free.
My best, Dick

Drew Frye

You can get a an ASAP Lock, which will function as an ascender, allowing you to push it ahead and lock it. Handy for possitioning also. The Goblin also has this function.

The ASAP Lock is effectivly identical, with added feature.

Drew Frye

Locked and pushed ahead, the fall is limited to rope and harness stretch, typically just a foot or two. I often do this with the Goblin when climbing hard moves above a bad landing.

Fernando Ostos

Has anyone used a GRIGRI?

Chuck Batson

I do use a GriGri as part of a holistically-designed mast climbing system, on the way up to hold my weight while pushing the ascender up, and of course on the way down. It’s crucial to thread the rope in the correct direction and have the carabiner go through both holes to keep the cover plate in place. I consulted with a professional climbing instructor to design my system.


Lots of ideas and techniques. In my experience problems are more likely from poor execution of a particular technique rather than the wrong technique. I keep a bag for the climbing kit AND a laminated card describing how we are going to do things. I typically sail with 2 or three others of varying degrees of experience so a simple system, well explained is critical…. oh, and a 60kg 22 year old to go up the mast!
For single/short handers it’s a different story.

Arne Mogstad

Hi. Great article and many good points! So, some of this have been mentioned already, so I will just briefly add to that:

I have used the ASAP a lot (mostly in alpine rescue settings), and it is never lifted. As Drew says, it works by speed. So unless you have a very long tether, there’s no benefit to lifting it.

The GRIGRI is, as is mentioned, a belay device and descender. It locks incredibly quickly and hard when taking a fall, and using it in a dynamic system require some serious thought. It is normally used attached to a climber that is standing on the ground. If the belayer is catching a fall, the person will be lifted and thereby add dynamicness (is that a word) to the system. I use the GRIGRI a lot, however used as a fall arrest device in a somewhat static system, I would be very reluctant! Using it as a part of a system for ascending ropes like described in a previous comment, is absolutely fine.

As to your idea of letting Phyllis lower you after you’ve taken a fall and you’re unconsciously hanging on the backup that is tied around the mast: If the backup halyard is routed inside the mast, that will be VERY difficult to do with any sort of knot, unless you have enough halyard available to just offload it with the double-rolling-hitch, and then untie it from the mast to move it to a winch. Then untie the double-rolling-hitch and lower from the winch with the excess halyard. My halyards are not that long on my boat, so that’s not an option for me. For my boat, I don’t have a good solution to this problem. However I mostly singlehand so there’s no one to lower me down anyway.

And lastly, as I mentioned in an earlier comment, the way things load up, the distances you fall, and directions you go when loading up a slack system, never cease to amaze me! Add a bigger fudge-factor than one would think.

I hope this is in any way helpful. I do find these articles very good! And also, even if one can’t eliminate every potential pitfall, the more pot holes one can cover in the system, the better!