Chairlift

A chairlift is the most stripped-down aerial ropeway there is: a bare bench, a bar across your lap, and a steel rope that never stops moving. No cabin, no doors, no floor — you sit down outdoors and ride the mountain in the open air.

How it works

A single wire rope runs in a continuous loop between two terminals, wrapped around a large bullwheel at each end and carried aloft by towers in between. One bullwheel is powered; the other keeps the rope under tension as it stretches and contracts with load. Chairs hang from the rope and ride up the mountain on one side of the loop while empty chairs circle back down the other.

Loading is choreographed: you walk into a marked spot, a chair swings around the terminal behind you, and you sit down as it scoops you up. At the top you stand and ski away as the chair rounds the bullwheel and heads back down. Nothing ever stops — the rope just keeps turning.

Fixed-grip vs. detachable

Almost everything about how a chairlift feels comes down to one detail: how the chair clamps to the rope.

• Fixed-grip. The grip is bolted permanently to the rope, so the chair travels at exactly rope speed everywhere — including through the station. To keep loading survivable, the whole rope runs slowly (around 2.5 m/s). Simple, cheap, and reliable, but a fixed quad tops out near ~2,400 people per hour.
• Detachable. Inside the terminal the grip springs open and hands the chair off to a slow rail. The chair crawls for loading, then re-clamps and accelerates back to full line speed — often 5–6 m/s. This is the "high-speed quad" or "six-pack," and modern detachables move 4,000+ people per hour.

The entire difference lives in one clever part — the detachable grip — which decides, hundreds of times an hour, whether to hold the rope or let go.

From banana hooks to Sun Valley

The chairlift was invented for Sun Valley, Idaho, which opened the world's first ones in 1936–37. Engineer James Curran had built conveyors that loaded bunches of bananas onto ships using hooks on a moving cable. He swapped the banana hooks for chairs and hung people from the rope instead. The idea worked on the first try and has barely changed in principle since — every high-speed six-pack is still a banana conveyor at heart.

Bars, bubbles, and comfort

Because riders sit in the open with nothing underneath, the main restraint is a safety bar that pulls down across the lap, usually with a footrest. Resorts add clear fold-down bubble canopies as windshields and heated seats, turning a cold exposed ride into something almost cozy on a storm day.