Team of 3 in moderate terrain? Try end roping

Note - This post discusses techniques and methods used in vertical rope work. If you do them wrong, you could die. Always practice vertical rope techniques under the supervision of a qualified instructor, and ideally in a progression: from flat ground, to staircase, to vertical close to the ground before you ever try them in a real climbing situation.

Scenario: You have a team of three climbers and one rope. You’re in moderate technical terrain - low fifth class rock with good climbers, 4th class with occasional “steps” of harder moves, a open big slab, or fairly steep snow. The terrain falls lies that in-between spot, ranging from “No prob, I can solo this!”, to, “Hmm, I think I want a rope!”

This might be a good time for end roping.

Look! It’s our friend Sticky! She’s back, and climbing with her 2 pals. Hi Sticky!

This is a technique often suited to alpine climbing, where you may have many pitches of easy to moderate climbing, and speed can become more important. It’s best not to use it on much anything higher than mid 5th class.

The leader heads out as usual, but the two followers tie in close to each other near the end of the rope. (End roping, get it?) The leader then belays up both followers at once.

The “end” follower ties in to the rope end as usual with a rewoven figure 8 knot. The “middle” follower, about 4-5 meters away from the end person, ties in with one of several ways, more below.

With the middle person on a large bight of rope, it gives them some freedom of movement. If the end person falls, the middle person may not be pulled off because of this loop. And, it means the followers do not have to be moving at the exact same rate.

A few things to note:

You need to use a single rated rope, not a skinny twin or double.
This is ideally for rock and maybe steeper snow. For ice climbing, you always want your seconds on separate ropes and end roping is not a good choice.
The anchor needs to be especially stout, because it could potentially be loaded with the weight of two people with a little slack in the rope.
If the last person falls, it’s possible they will pull off the middle person. Because of this, it’s best if the strongest climber of the two followers is on the end of the rope.
This is really only a safe system up to low fifth class for most people. For more difficult terrain, you probably need a different rope system.
If you're in an area where the rope is going to be potentially loaded over sharp rock edges, keep in mind that you could be putting a double load on the rope if the seconds fall together.
This works best if the route is pretty much straight up. If you start any kind of a traverse, a slip by either of the two followers will probably result in a fall for both of them.
Communication between the belayer and the followers needs to be clear and obvious, in case something goes wrong. If the route is long, it goes out of sight around the corner, it's a windy day and it's hard to hear each other, or all of the above, this may not be the best technique.
The large loop connecting the middle person to the rope is a bit of a trade off. The loop can give you more freedom of movement, but it also can also be a tripping hazard. Use your judgment here. A smaller loop (1-2 feet) might be a better choice depending on terrain, skill of the climbers, if you have crampons or not, etc.

Use some common sense. If the consequences of a fall are low, meaning the terrain is a slab or snow or not very blocky, and it goes pretty much straight up, and your climbing team is skilled enough to mean a very low chance of a fall, this technique will probably work fine.

Anything more advanced or difficult than this, you're probably better off using a two rope system and bringing up each climber on a separate rope.

There are a few ways for the middle person to connect to the rope. Here’s one that's pretty straightforward - tying in directly to your harness with the rope. There are a few ways to do it. This example uses a bowline knot.

1 - Tie an overhand knot, leaving a large bight of rope about 5 feet long.

2 - Pass this bight through the two tie in points on your harness, and tie a bowline knot. (Yes, you use both strands of rope, and this might look a little funky if you've never done it before. It's the exact motions as tying a bowline with one strand of rope.)

3 - Finally, secure the tail of the bowline with a locking carabiner to the loop through your harness.

Another option is to clip this bight of rope to the middle’s belay loop with two carabiners, opposite and opposed, with at least one being a locker. (If you are feeling a bit bold, one good locker with the carabiner properly aligned with no chance of cross loading is probably okay too. It's really up to your personal level of acceptable risk. Me, I like two carabiners.)

Cross loading the carabiners is the main thing we're trying to avoid here. There are several ways to avoid this:

Use the belay loop rather than the harness tie in points, as this minimizes tri-axial carabiner loading.
You can tie a clove hitch in the bight loop and crank that down on your carabiners.
You could use a nifty new-school locking belay carabiner, like the Black Diamond Gridlock, that has a clip that captures the carabiner so it can’t be cross loaded.