Historically the Western default number in a climbing team is generally two, a number that allows swift and belayed movement, with group gear (stoves, food, tent) being dived, as well as the number of pitches led. As with all climbing dogma, it’s worth looking at why this is, and if it’s a sound way of doing things, after all in places like Russia, teams on hard big routes tend to number 4.
Most climbers begin on outcrops (or in climbing walls), where the optimum number is always two, allowing the most climbing to be done with the least fuss. Just think how people tend to approach breaking up into teams, if there is an odd number then mentally their is a negative value applied to the single climber who must be added to a two person team. Basically we’re tought that three’s a crowd.
But moving away from outcrops their are many many advantages of climbing as a three. Group gear can be divided between three (you still have the same rack. Ropes, and stove as two), as long as both seconds can come up at the same time their should be no loss of speed, in-fact speed could be increased on very long routes, as the sharp end can also be divided up. This can be crucial on low angled alpine terrain and in deep snow, as rotating the ‘snow plough’ upfront will greatly speed up your team. The psychological effect of a three is also huge, not only in retaining belay station psych, but also giving a large and combined bulwark against the weight of a big climb, let alone combined skills, experience and problem solving.
Of course the fasted team will always be a team of one (if they climb unroped), and hence a two person team that is acting as if each is soloing (moving together), will also be faster.
A team of four tends to work in a kind of spearpoint and shaft style, with the spearpoint pair doing the climbing, while the shaft pair carry all the gear and keep the spearpoint heading for its target. This system works really well (like a three) on super alpine objectives and hard big walls, as the lead team can be swapped each day, even to the point where one team can have a day off (if the climb is going very slowly). Russian teams also tend to split the team up in order to focus on their strengths, perhaps with the two heaviest climbers just hauling, while the best climbers lead (or even have one climber lead the whole thing). This system my seem very undemocratic, but it’s worth considering during hard times, as fielding the best team in the best positions is what wins a match.
Alpine technique for parties of three
For alpine climbing a two rope system (probably avoiding super skinny ropes!) with one person leading and two seconding together works really well.
Advanced alpine technique
For routes where you may want to move together as a three then climb as a line of three, perhaps if you’re on ground you’re happy to solo, then have one climber on each end of one rope, and one tied at the end of both thier ends (so you have a 120 metre rope, with one climber at each end, and one at the middle). You can now shorted the rope by taking coils, or climb like that, with the climber in the middle switching protection from the rope above to the rope below them (very important on traverses). With this technique you can use ropemen or tiblocs as protection for a fallings second, but again the middle climber must switch these over as they go.
Big wall technique for parties of three
Big wall teams of three have a few options:
With this the leader will climb a block of pitches (a 3rd of the route if speed climbing). Once they are at the belay they pull up all the slack in the lead rope and rebelay it, so they can rope solo the next 10 or 20 metres. They then attached the haul line and start climbing, limiting their time at the belay to less than a minute. At this point one second jugs up the haul line as fast as they can, with the haul bag being released as soon they they reach the belay (or at the same time if you’re brave or have a light bag). Once the bag is free the the others second sets off cleaning, passing this gear to the leader once they reach the belay (by this time the other second should have the bag up). The best thing about this system is that the work of climbing a wall is devided between three rather than two, plus walking off is much easier with a big wall load with three pairs of legs!
Classic three person speed system
With this system, once the leader reaches the belay and ties off both lead and haul lines, one second jugs the haul line with a spare rope, and once at the belay begins climbing the next pitch while the old leader hauls and the last second cleans. Using a zip line is best with this system and requires good team work, and jugging a free hanging rope with a chunky lead line attached to you is harder than you’d image. Fo this reason I’d recommend a modification of using the short fixing method, pulling up all the slack in the haul and lead lines and using this for the leader (unless the next pitch is all free climbing, which will go faster than the second can clean).
Standard three person big wall technique
With this one second jugs up the haul line and one jugs up the lead line, and is probably no slower than a two person team if the second can jug fast.