There are two sides to every engineering project; functionality and user experience.
Both are essential to the long term success of the solution.
I’ve come to the Prague city hall for their paternoster elevator.
In terms of functionality, it’s the world’s best.
For user experience, well, there’s a reason some call it the Elevator of Death.
We’re now moving up inside the building.
As we approach level two we could jump off now...
but we want to go a little bit higher.
As we approach level four, a sign says Vystup – which is Czech for exit.
At this point we can simply step outside of the elevator shaft.
That is such a better experience.
Just jump on and jump off.
No waiting around.
We’re now at level four, which is as high as this building goes.
The staircase doesn’t go up any further than this, but the lift does.
So, what happens if you enter the lift at the top level and then keep heading up?
As we ascend, we can see normal wooden boards, bit of light here and there… and now a massive wheel.
[Whiiring cogs and low rumble]
Heading back down we can just step off… and we’re back to level four.
We went up that side and then back down that side.
We turned around somewhere in the roof.
Inside the roof we find another room, filled with engines and gears.
If you wait around long enough you’ll even see a cab come around.
This gives us some clues as to how the elevator might work.
These are all the things that we’re going to need in order to create a small-scale model
of the paternoster elevator.
After spending the afternoon building and debugging, we now have a working model of
the elevator.
These four wheels are what allow the whole thing to operate.
These two are the ones we saw when we went over the top, and then around the bottom.
The ones at the back make sure that the elevator going up doesn’t collide with the other
ones coming back down.
The cabins are connected one after another, making a continuous loop.
The resemblance of this structure to prayer beads is how the paternoster elevator gets
its name.
This daisy chain allows us to have many simultaneous journeys taking place at the same time.
Vastly increasing the carrying capacity of the system.
As the building gets taller, we can add in more and more cabins – making the elevator
even better.
So if these elevators have such good function, why aren’t they installed in more places?
I’ve had to come all the way to Prague to find one in working condition.
The problem is user experience.
Getting into and out of these elevators is actually pretty difficult.
From 1970 to 1993 five people were killed using elevators just like this one, and many
others have been seriously injured.
There are some ways to improve safety, such as installing handrails and having an emergency
stop button.
However, these don’t always work – especially if the emergency stop button is on the wrong
side of the cabin.
Even though these elevators can move a lot of people and have effectively zero wait time,
the prospect of potential death is just too negative a user experience for these machines
to be viable in the modern day.
Since 1994 the installation of new paternoster elevators has been banned in many countries.
The places that do still have them are gradually ripping them out to be replaced by their safer,
if less fun, counterparts.
If safety isn’t a key issue, then we can use this design to move packages around a
facility, or as a new type of mountain lift for thrill-seeking skiers.
The elevator of death lives on.