I spent the last weekend of November 2022 in London.
Mostly, I didn't do anything worth writing about. Walking around. Looking at shops. Complaining about the lack of bookshops. (Though it turned out that one of the better and larger Waterstones bookshops still existed.)
But on Sunday, I did something that's not one of the default London experiences.
I did an abseil down the ArcelorMittal Orbit.
The Orbit Tower (the ArcelorMittal part of the name is from the company that sponsored the building) is a large sightseeing tower / sculpture that was build as in the Olympic Park for the 2012 Olympic Games.
The central column is a rather dull steel shaft, housing the elevator, with a spiral staircase going down around it. (Ok, technically it's also going up around it, but most people use the elevator on the way up and then the staircase for going down.)
What makes the structure visually interesting is a red steel lattice that goes around it in a asymmetrical, knot-like structure. Or, if you want to see it that way, like a gift-wrap bow around the tower.
Though, ultimately, I wasn't much interested in the look or shape of it. I was more interested in going to the observation level and then going back to ground level, using neither the stairs nor the elevator.
I did do an abseil from the Euromast in Rotterdam two years earlier. So it seemed like an interesting thing to do something like that in London as well.
The abseil height is a bit less in London (80 meters instead of 100 meters). But when you're hanging on a rope high above ground level, these 20 meters don't make much of a difference.
I got to the Orbit Tower early, as there was a half-marathon (and a 10K run) going on around the former Olympic Stadium. So I wasn't sure how crowded public transport to the venue would be and how much of a detour I would need to make to go around the runners to the Orbit Tower. (The answer to both turned out to be 'not that much', but I didn't know that.)
I got into the abseil gear and up to the observation platform.
The atmosphere up there was interesting with some mutual admiration.
Every half-marathon finisher with a medal (and probably the 10k runners as well) had free entrance to the Orbit Tower that day. So most of the people up there had finished a half-marathon earlier that morning. Those of us in climbing gear were kind of impressed by those half-marathon finishers, while they were, kind of, impressed by people going down the tower on a piece of rope.
(Almost forgot to mention - there's not only the elevator, the staircase and the outside rope to get from the observation platform back to the ground - there's also a slide that is threaded through the steel lattice in twisty ways. But the slide was closed for the day, so nobody was taking that way down.)
In most cases, two people abseil from the tower at the same time, as there are two sets of ropes installed.
But there was a small mishap with one of the two people preceding the two in front of me.
When you abseil down an overhanging platform (as opposed to going down along a wall), you need to keep your feet on the edge (or some stepping area below it) and then lower your upper body until the feet still touch the platform, but your upper body is well below it. Ideally you do that until you're hanging almost upside down.
Only then do you take the feet of the platform. (Although in most cases you don't actively do that. You keep abseiling until you're so far below the platform that your feet stop touching it and you swing around to the normal position - head over heels.)
The reason for this is that you don't want to scrape with the climbing gear along the edge of the platform. So you lean back at the beginning to get the rope (and everything attached to it) away from the platform.
And you want the rope to go smoothly back against the edge (where it will be for the rest of the abseil), which is why try to go as close to upside down below the platform as possible. Then the rope touching the edge of the platform again and when you 'step off', the rope doesn't suddenly swing around.
So far, so obviously sensible.
However, there can be a bit of a problem when you lowered your upper body so far that your head is about the same level as your feet (when you are more or less 'standing' there horizontally on the platform edge) and your feet slip off and under the platform. Then your upper body slams into the side of the platform, which can be unpleasant.
With the safety lines in operation at the Orbit Tower, there's not a lot of real danger involved. You're wearing a helmet, so it's unlikely you injure the head by bashing into something. You swing only for about half a body length, so the sideways impact is about the same as standing a meter in front of a wall and jumping against it. If you're unlucky, there might be a bruise later, but not much more. But if you're dangling on a rope 80 meters above the ground, it can be a bit unsettling. Although it might scarier to a spectator than it is to the person on the rope.
There's some real danger involved in this when you do an unsecured abseil. If you're with an abseil eight on a single rope, then the risk is not so much in the slam against the wall. The danger is that you instinctively use your hands to brace for the impact. Because then you let go of the rope below the abseil eight and slide down the line without braking. Which is likely to cause problems.
Although that won't happen at the Orbit Tower as there are extra safety measures. Even if you completely let go of the rope you're hanging on, you won't hit the ground at speed.
The reason for explaining all this is this: Of the two people preceding the two in front of me slipped off the side of the ledge when descending and banged right against the side of the platform. This looked a bit scary from above (as you could see her slowly descending, suddenly slipping out of view and then hear her bang against the wall), but otherwise not a problem. After a few expletives she continued her abseil without further issues.
Then the next pair of rappellers stepped out onto the platform and were clipped in.
One of them got over the edge and abseiled down, but the other one did have second thoughts and, after being all clipped in and ready to go, asked to be clipped out again, go back inside the tower and use the elevator to go down.
So they asked the next one in line (me) to step out onto the platform.
By the time I was ready to go, the person on the other line was almost at the bottom of the tower, so I was going down the rope (essentially) beside an empty rope.
After everything is set up, you step on the edge, lean back and they'll take a picture of you. Although that tends to look (almost annoyingly) boring and mundane.
You are already outside the platform, with an 80 meter drop below you, holding onto the main rope, worrying about slipping off, while trying to look confident (or at least not overly panicky) at the same time - and the picture looks like you're standing on a viewing platform somewhere, leaning against a guardrail (the red metal tube behind me is part of the lattice structure around the tower and a good three meters behind me at that point).
I think it would look a lot better if they did put in a camera somewhere above the platform and include more of the ground directly below (and not some distant scenery). The images taken at the Euromast in Rotterdam look slightly more impressive in that respect...
But at least the picture showing the guide taking a picture helps to explain the rope setup.
The configuration used at the Orbit Tower involves three ropes per rappeller.
The main rope is the white one in the middle. That's the rope that goes through and around your abseil eight and the one you abseil down on. You grab the rope below the abseil eight (with gloved hands) and how hard you grab the rope determines the speed of your descent.
You are also attached to another rope (the blue one) with an auto-brake device. On a normal descent, this doesn't (and shouldn't) do anything. It simply slides along the rope. But if the descent is too fast, it clamps onto the blue rope and stops the descent. It acts as an emergency brake in case someone lets go of the white rope or the abseil eight breaks. The it's not a smooth stop, though. The safety device is called a 'fall arrester' (a Petzl ASAP Lock) and, like the locking retractor on a seatbelt, it suddenly stops the movement. Which is the reason why it's not directly clipped into the climbing harness. If something goes wrong and you're heading towards the ground at high speed, then being suddenly stopped by the harness is only a marginal improvement over suddenly stopped by the ground. (Yes, the terminal velocity before stopping might be lower, but still...) So there's an energy absorber between the fall arrester and the harness (like the one you would use on a via ferrata). If the brake clamps onto the rope, an elastic band will dampen the effect (like a mini-bungee rope).
The other safety device is the yellow-green rope. While the other two ropes hang down from the tower to the ground (with the white one hanging free and the blue one fixed to the ground), the end of the yellow-green rope is attached to the harness. The rope then runs through a belay device and allows the guide to slow your descent from above. The rest of that rope is in a large bucket beside or behind the guide and let down while you descent, so once you're back on solid ground, you unclip that at the guides hauls it back up. While the guides can use that rope to slow your descent, they pretty much only use it as safety device in case something goes wrong. We were told in the beginning - as long as you look like you're in control of the descent, you can go down at quite some speed. So if you feel like doing an 'action movie' abseil, they won't (within reason, presumably) spoil the fun by slowing you down. The purpose of that rope is (in addition to being a second failsafe device) to get people safely to the ground in case of problems. For example, if someone becomes unconscious during the descent or takes the hands of the rope. In general, this is preferable to using the auto-brake, as this will leave the person hanging somewhere along the way. Then someone needs to descent to the rappeller and 'unclamp' the fall arrester (not a trivial thing) or, possibly cut or untie the blue rope and lower the person with the yellow-green rope afterwards. So it's preferable to use the yellow-green rope as the primary safety device in case there are any problems and only rely on the clamp on the blue rope to keep things that go wrong from getting disastrously wrong,
After all this text about safety measures - nothing went wrong during my descent and the text is mostly there to keep the description of the experience from being only two or three lines long (if even that). ("Went up, abseiled, got back to the ground safely.")
On the two pictures above, you can see the edge of the platform. I'm already past the first parts (the silver metal tubing and the tread plate below it) and am now 'standing' on a white metal box below. This is the section where it is important to have your feet on the yellow-ish stripes, as these are adhesive tapes that keep your feet from slipping off. The person who went down that rope before me did put her feet on the metal itself, which was the reason why she slipped and banged against the side of the platform.
I made sure that my feet were safely on the yellow-ish stripes (and the guide probably had a closer look and a tighter grip on the yellow-green rope than she usually has) and everything went without a problem. In the second picture my upper body is already well below my feet (and the ropes are already resting against the edge of the platform) and the 'stepping off' the tower went smoothly.
There's a second 'observation level' directly below the one I left from, giving me a chance to look at my reflection in the mirror before continuing. The Olympic Stadium can be seen to the left.
It was all downhill from there. (And how could it not be?)
On the first few meters, the abseil was close to the some parts of the red lattice structure surrounding the tower. It's also not too far from a transparent section of the slide, so someone abseiling could see someone sliding down on a day when the slide is operational. (The oddly shaped building on the left is the London Aquatics Centre, which was also built for the 2012 Olympic Games.)
After the first ten meters or so, the ropes are no longer near any part of the tower, so there's a bit of 'hanging free in the air' feel to rappelling that you don't get when going down a rock face or a house wall.
Although, admittedly, the freedom to look around was smaller than it was on the Euromast or on a rappel I did in Brazil. On both of those occasions, I was hanging on only one rope (although there was an additional belay rope from above in Brazil), so I could turn around freely and look to all directions.
Here I was not only descending on the white rope, but also attached to the fixed blue safety rope. So I couldn't turn around and have a look at the scenery away from the tower. It didn't matter much (after all, I could look at the scenery in all direction while standing at the top of the tower), but it gave the abseil a slightly different 'feel'.
An the plus side, it was a much smoother experience than it had been in Rotterdam.
While being fun, that Euromast abseil turned out to be harder work than expected. Instead of a single rope, the abseil there uses two ropes going through the abseil eight. This not only increases the friction on the abseil eight. It also makes the descent slightly more 'jerky' (as the ropes don't always run smoothly in parallel, but sometimes twist against each other). More importantly, it also means that the weight of two ropes below is putting tension on the abseil eight. Since the speed of the descent is controlled by the 'pull' on the rope below the abseil eight (which is usually provided by the hand of the rappeler), this meant that at the beginning of the abseil, the weight of the ropes alone was sufficient 'pull' to keep me from going down.
So for about half of the Rotterdam abseil, I wasn't braking my descent, but actively feeding the ropes into the abseil eight to keep moving. Only when I was about halfway down was the remainder of the ropes 'light' enough that I started sliding down on my own. So I probably had to lift, on average, 2x75 meters of rope with my arm for around a hundred times before I got into the section where gravity alone was enough. Admittedly, not a really hard task, but it was something I didn't expect to happen.
Here, on the London abseil, it was only light work. On the first ten meters or so I did a bit of 'rope feeding', but that was to speed things up a bit. After that, things got considerably faster. I didn't try to do a 'speed run', but I did grab the rope lightly (I did most of the speed control by the angle in which I held the rope and less by applying pressure on it) and was pleasantly surprised that they didn't slow me down with the belay rope from above. As long as it looks like a controlled descent (and you're not about to smash into the ground in a second), they pretty much let you do what you want.
A short time later (about two and a half minute after my feet left the platform) I was back on solid ground.
After that, I did take the tube and then walked around a bit more in London, having a look at Battersea Power Station, which had only been recently opened (as a shopping mall) a few weeks earlier, but didn't do anything interesting. (I didn't even take the elevator that goes up one of the chimneys of the former power station to allow sightseeing from top. After abseiling from the Orbit Tower, riding an elevator up and down again seemed somewhat anticlimactic.)
