Hi Duncan, thank you for your comment.

I can understand why you think this, but I assure you I tested that setup a number of times before I went up the mast. Despite the nylon safety line being a larger diameter than would usually be used on a line with the diameter of the topping lift, I tested it by pulling on the prusik lots of different times, from different directions, and in different ways (i.e. sharp tugs, slowly increasing the load etc.) It didn’t slip at all. Not once. After these initial tests I again tested it using my body weight and had exactly the same result. If anything it was almost too ‘grippy’ making it a tad difficult at times to slide it up and down with me. (The topping lift outer core is very rough on our boat, if it was a new line the results may have been different.)

Regarding ascenders, let me quote a section from the book “Climbing Self-rescue: Improvising Solutions for Serious Situations ” in the context of moving up and down fixed lines.

“Compared to friction hitches, mechanical ascenders have several advantages: they are extremely easy to clip on and off the rope, they slide with great ease, and they offer a comfortable grip. There are, however, disadvantages to using mechanical ascenders: they are heavy, expensive, and their application is more limited than a set of prusiks.

Mechanical ascenders, if used at all, should be used with great caution when belaying or hauling . Testing shows that a shock load on mechanical ascenders can dangerously damage the rope – even shred the core. Because of mechanical ascenders small camming area, in the event of a fall the rope can be severely damaged at as little as a third of the rope’s rated strength. We do not recommend using a mechanical ascender in a raising system.

There are a few ascenders that are light and small. The Wild Country Ropeman and the Petzl Tibloc are two examples. These devices solve the weight issue whilst being quick and easy to use. They still have the disadvantage of being able to severely damage (even cut) the rope in a dynamic loading event, and they are not releasable under a load. Prusik hitches are the rescue tool of choice despite the apparent advantages of a piece of manufactured gear and easy application”

[I was unable to copy and paste the above, so had to type it all out manually!]

Thank you for sharing your opinion, we can all learn from each other and as this is an important subject it is good for there to be a healthy discussion about our various techniques.

Fair winds,
Chris