13 replies to this topic

[Old Timer]

I heard some ski patrol chatter on Sunday that there was a Return Terminal incident in New Hampshire? Any confirmations?

[Emax]

Old Timer, on Jan 2 2008, 08:48 AM, said:

I heard some ski patrol chatter on Sunday that there was a Return Terminal incident in New Hampshire? Any confirmations?

Confirmed. Discussion at a later time - when actual facts are known. Right now, it's all "yellow press".

[Old Timer]

Emax, on Jan 2 2008, 12:18 PM, said:

Confirmed. Discussion at a later time - when actual facts are known. Right now, it's all "yellow press".

Thank you, standing by.

[Peter]

It is the North Peak Triple chair at Mt. Sunapee.

From the SnowJournal.com forums...

Quote

Here's the best article/video clip I've seen (note that in the video clip, the first guy they show as "Jay Gamble" is not Jay Gamble - he speaks later witht he correct caption):

http://www.wmur.com/...355/detail.html

boybud can probably provide more detail on this, but...

It appears that the bearings on the top bullwheel went bad. As stated in the video clip, they observed some issues earlier this week and were planning to service the top bullwheel.

Generally, one is able to observe a) excess vibration from the top bullwheel b) a clicking on every rotation of the bullwheel c) a grinding noise as the bullwheel rotates d) visible movement of the bullwheel as it rotates. Knowing the folks at Sunapee, it is likely that the signs were very minimal, hence their decision to wait on servicing this.

My guess is that the boy who fell off may have had his safety bar up in preparation for unloading. Another possibility is that his chair was bounced when the cable deroped off the idler sheaves (I think that's the start of the deropement in the video clip, though it looks like its off a full uphill sheave too).

What causes bullwheel bearings to go bad? It's a pretty rare occurence in most lifts (though some brands have this happen more frequently). Often times it's caused by lightning or moisure/some other foreign matter getting into the grease/bearings and freezing/thawing.

It's a pretty big deal to service this - its a multi-day fix that requires detensioning the cable, etc.

[skierdude9450]

Wow that sounds a lot like the Teller lift accident at Keystone. It is a good thing that only 19 people were on the lift.

[Peter]

I don't think a bearing breaking is quite like a faulty weld where the bullwheel falls off completely. The media might want you to think so though!

[Lift Kid]

I don't believe that the bullwheel came off, like on Teller. It broke a bearing, which caused the line to bounce vigorously.

[ski89]

The Bullwheel came off and ended up 40' down the mountain.

[Peter]

ski89, on Jan 3 2008, 03:28 PM, said:

The Bullwheel came off and ended up 40' down the mountain.

I don't believe it.

The news report cited above showed the lift from the bottom and it appeared to still be somewhat tensioned. Industry people, would a bearing failure really cause a bullwheel to fall off? Ski89, what is your source?

Attached File(s)

•  northpeaktriple_2006_0402d.jpg (58.25K)
  Number of downloads: 39

This post has been edited by Skier: 03 January 2008 - 04:09 PM

[liftmech]

I haven't heard official details, but- if the bullwheel were to fall off, chances are the rope would drop and be stopped by the support structure for said bullwheel. This would only allow it to move downhill a small amount, say 15', and it would still be 'somewhat tensioned' as you say. I have also heard the 40' downhill story, but as I said it's not official. As none of us has heard official confirmation of anything in this incident, let's not speculate until we do. It's not likely we will know anything until the investigation has been concluded and made public.

[ski89]

I'm going to let this one go. All bullwheels should be retained in order to prevent them from traveling down the hill. That's what I have learned from this incident.

[Ryan]

If you look at this illustration from ColoradoSkiHistory you can see it fell down and was restrained.

Attached File(s)

•  ky_yan_0002.jpg (36.13K)
  Number of downloads: 53

[aug]

As a result of an earlier accident new design criteria was adopted for DRIVE terminal BW retention in case of bearing or shaft failure. Many older lifts needed to have BW catchers installed at the drive terminal . I have not seen any upgrades to older lifts at the return (idler) terminal for BW retention

[Old Timer]

Does anyone know if lift operation incidents are reviewed thru NIOSH?