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justthemaid
climber
Jim Henson's Basement
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Mar 16, 2018 - 11:05am PT
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OMG^^^ Ski lift goes totally haywire.
NOT.. jumping for your life...
was NOT an option.
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monolith
climber
state of being
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Mar 16, 2018 - 11:05am PT
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I hope they build their pedestrian overpasses better than we build ours.
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Reilly
Mountain climber
The Other Monrovia- CA
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Mar 16, 2018 - 11:45am PT
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It ain’t Russia, homes. But why wuzzit running backwards?
Having been on quite a few Rooskie aircraft I don’t plan on getting on any more if I can help it.
I prefer my mechanics sober.
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Rollover
climber
Gross Vegas
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Mar 16, 2018 - 11:49am PT
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HO LEE FUK!
Worst nightmare as a lift mechanic!
Why didn’t the rollback dog brake engage!?!?
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WBraun
climber
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Mar 16, 2018 - 11:54am PT
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Meh ... more Russia bashing by st00pid brainwashed Americans.
This very same thing happened on Chair 2 in Mammoth in the 70's.
The bullwheel brake failed and the cable went backward throwing people off the chairs on their way back to the loading ramp
until one of the chairs jammed itself into the bullwheel.
I was right there working Chair 2 when this happened.
It's NOT a Russian thing only.
The dumb ass American media is obsessed with bashing Russia and Putin.
st00pid brainwashed Americans .....
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Reilly
Mountain climber
The Other Monrovia- CA
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Mar 16, 2018 - 11:57am PT
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It wuz GEORGIA!
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Reilly
Mountain climber
The Other Monrovia- CA
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Mar 16, 2018 - 03:42pm PT
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It’s simple. They ran out of quarters.
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gruzzy
Social climber
socal
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Mar 16, 2018 - 10:30pm PT
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We will probably find out soon enough about their aircraft
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Reilly
Mountain climber
The Other Monrovia- CA
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Mar 16, 2018 - 11:48pm PT
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There's no free lunch, especially in aerodynamics. Yes, Rooskies design
good aircraft per their design parameters, such as operating from secondary
airfields. But designing intakes such that they are less likely to ingest
foreign objects mean they don't ingest air as well. That's why nothing
could touch the Tomcat, the Strike Eagle, or the Fighting Falcon. The
Rooskies design good aircraft, but we design the best.
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neebee
Social climber
calif/texas
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Mar 16, 2018 - 11:59pm PT
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hey there, say....
oh my... also, liked werner's bit of history, as to
what happened...
will go read about bullwheel brakes...
good that it was not worse, :O
thanks for some tech-stuff, here, to go learn...
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John M
climber
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Mar 17, 2018 - 12:32am PT
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Tad..
I am not an expert, but have worked a few lifts. Most lifts have multiple brakes. Some on the drive shaft and some on the bull wheel. One reason a lift can spin backwards is if a drive shaft breaks. That negates the driveshaft brakes which are usually the main brakes. ( In my limited understanding )
The reason the lift spins backwards when being operated is because there is a greater load on the uphill side with all the skiers. With no brakes, gravity takes over.
The bull wheel also has a number of different mechanisms that are used to keep it from spinning backwards. I believe that some lifts have a friction brake on the bull wheel. Plus there is some form of an anti roll back device. I worked lifts over 20 years ago, so this is likely old knowledge, but we still have lots of older lifts out there. One anti roll back device I have seen worked like a kind of ratchet. A gear on the bull wheel had teeth on it. A metal bar laid over those teeth. As long as the bull wheel turned in the proper direction, the bar would slide over it. If it started to spin backwards, then it would drop into place and stop it. I do not know if they still use this kind of anti roll back device, but I doubt it. This kind of device needs no activation. So it is a failsafe device.
Another antiroll back device is called a dog pin or drop dog. It is a large steal pin that can be dropped into the spokes of the bull wheel. This is a method of last resort as it would destroy the bull wheel and if the spokes break, then other catastrophes can happen, such as the bull wheel dropping and dropping the cable. Plus if it is activated and the cable is spinning very fast, then the sudden stop would cause the chairs to swing wildly. That could cause many people to be ejected from chairs while high off the ground.
For a catastrophic rollback to occur, there needs to be a number of failures.
This is just my limited understanding.
Here is another video of a chairlift spinning backwards during a test.
[Click to View YouTube Video]
Edit: this article describes the causes of one accident at sugarloaf.
http://www.saminfo.com/headline-news/8089-14005-687-sugarloaf-releases-preliminary-findings-on-lift-rollback
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hossjulia
Trad climber
Carson City, NV
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Mar 17, 2018 - 07:37am PT
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That's a classic lift op training film. There was a broken leg involved in that film from what we were told.
Guardia is blaming the haul rope manufacturer. I'm not getting how that could cause multiple braking systems to fail.
Another report says the lifty "accidentally shifted it into reverse", and in trying to correct it broke the transmission. That doesn't sound right at all.
We may never hear the real reason. Doppylmayer is investigating too so there may eventually be a report from them.
Werner is spot on again.
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Jon Beck
Trad climber
Oceanside
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Topic Author's Reply - Mar 17, 2018 - 07:39am PT
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I will not be able to ride a lift without planning my escape from a failed brake
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Chaz
Trad climber
greater Boss Angeles area
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Mar 17, 2018 - 08:14am PT
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In Soviet Russia, ski lift rides you.
What a country!
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justthemaid
climber
Jim Henson's Basement
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Mar 17, 2018 - 11:06am PT
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FYI sidebar: Georgians HATE being called "Russians" just ask one- they will emphatically tell you so.
...chairlift engineering notwithstanding.
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Toker Villain
Big Wall climber
Toquerville, Utah
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Mar 17, 2018 - 01:34pm PT
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But the lift tickets are much lower than here.
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Jon Beck
Trad climber
Oceanside
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Topic Author's Reply - Mar 17, 2018 - 01:53pm PT
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But the lift tickets are much lower than here.
Cuz they take you down the hill!
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