It’s not an electrical issue. The breaks failed. The weight of the people riding up the slope are now going down hill. That’s why the lift is running backwards. Not sure how the crashing lifts stacking up at the bottom didn’t bind up the cable and stop it.
Former Ski Patroller here: the chairs disconnected from the haul rope. There are various ways to engineer that connection; every design in use has proper engineering factors for the intended load; at much higher loads, the connections are designed to tear out (or off) without damaging the rope.
The brake on a chairlift is more than enough to hold a fully-loaded upline in the stop position, and the motor is strong enough to start a fully-loaded line uphill from the stop position. If for some reason the whole motor-brake arrangement fails, the lift will naturally roll back. The process is sudden, not gradual.
There is a device on the bull wheel to arrest rollback. It's not a brake; it's a toothed component similar to a ratchet. This anti-rollback gadget is triggered by the slightest backward movement of the wheel; it drops down and positively engages ratchet teeth built into the bull wheel itself. This gadget stops the rollback within hand-shaking distance of where it started.
If the rollback continues for more than a second or two, not even the anti-rollback gadget can stop it. This scenario starts badly and only gets worse for a while, as you can see.
Strange as it may seem, aerial tramways (which includes chairlifts) are statistically the safest form of transportation*; safer than elevators, escalators, etc.
* In America. This rollback incident was somewhere else.
While standing in a lift line many years ago I saw a woman get knocked out by a chair. While she was trying to seat herself, the lift attendant pulled back on the support arm, too far. The chair swung forward and pitched her off, swung back, then forward again as she was trying to get up whacking her in the back of the head. Everyone in the lift line froze for about 10 seconds, then immediately decamped for another line. It took several hours for that lift to be returned to service.
"Ivan! Pull plug! Blyat!"
ReplyDeleteNow, its not my ski lift, but... doesn't anyone know how to open an access panel and find a breaker?
ReplyDeleteWow, aren't you the buzzkill.
DeleteSkiing seems fun
ReplyDeleteThe "ludicrous-speed quad" is an upgrade to the high-speed quad.
ReplyDeleteHey that looks relaxing.
ReplyDeleteIt’s not an electrical issue. The breaks failed. The weight of the people riding up the slope are now going down hill. That’s why the lift is running backwards. Not sure how the crashing lifts stacking up at the bottom didn’t bind up the cable and stop it.
ReplyDeleteI think you meant to say brakes, not breaks. Sometimes auto correct sucks.
DeleteFormer Ski Patroller here: the chairs disconnected from the haul rope. There are various ways to engineer that connection; every design in use has proper engineering factors for the intended load; at much higher loads, the connections are designed to tear out (or off) without damaging the rope.
DeleteThe brake on a chairlift is more than enough to hold a fully-loaded upline in the stop position, and the motor is strong enough to start a fully-loaded line uphill from the stop position. If for some reason the whole motor-brake arrangement fails, the lift will naturally roll back. The process is sudden, not gradual.
There is a device on the bull wheel to arrest rollback. It's not a brake; it's a toothed component similar to a ratchet. This anti-rollback gadget is triggered by the slightest backward movement of the wheel; it drops down and positively engages ratchet teeth built into the bull wheel itself. This gadget stops the rollback within hand-shaking distance of where it started.
If the rollback continues for more than a second or two, not even the anti-rollback gadget can stop it. This scenario starts badly and only gets worse for a while, as you can see.
Strange as it may seem, aerial tramways (which includes chairlifts) are statistically the safest form of transportation*; safer than elevators, escalators, etc.
* In America. This rollback incident was somewhere else.
While standing in a lift line many years ago I saw a woman get knocked out by a chair. While she was trying to seat herself, the lift attendant pulled back on the support arm, too far. The chair swung forward and pitched her off, swung back, then forward again as she was trying to get up whacking her in the back of the head. Everyone in the lift line froze for about 10 seconds, then immediately decamped for another line. It took several hours for that lift to be returned to service.
ReplyDeleteNemo
When HAL's grandchild A.I. goes into the "Kill Humans" mode.
ReplyDeleteAnd a tort lawyer, who was standing in the lift line, immediately handed out his business cards.
ReplyDelete"As god is my witness, I thought skiers could fly." Les Nessman, winner of the Buckeye Newshawk Award
ReplyDeleteHah!
DeleteI saw that episode just the other day.
But it was Mr. Carlson that said it, Les was kept in the dark until the last moment.
https://georgianjournal.ge/society/34329-full-story-of-gudauri-ski-lift-accident-chairlift-horror-in-international-media-spotlight.html
ReplyDeleteWiscoDave
Is that blood on the snow? Also somebody is gonna get killed in that pile of empty lift chairs...ouch.
ReplyDeleteGravity is a bitch
ReplyDeleteOne word, Maintenance!
ReplyDeleteStarker