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Came down after first lap and saw a gondy carriage completely fell off in the loading area. Everyone was ok from what I know but still scary. Not a good look for KH or RCR
cyphersholy fuck the hanger literally snapped. never seen that in my life. is it super cold up there or something
No it’s been between +3 and -8ish at the top. Hasn’t been -25 since like a month ago. Very catastrophic failure hard to say exactly how it happened, but it’s been long overdue for major repairs/ replacement
this shouldnt happen in the first place, but damn are they "lucky" that it fell where it did, any further up the mountain and it'd been lethal especially where the ridge opens up, wouldve been a long tumble down the mountainside.
WilliamHenrikgthis shouldnt happen in the first place, but damn are they "lucky" that it fell where it did, any further up the mountain and it'd been lethal especially where the ridge opens up, wouldve been a long tumble down the mountainside.
Yeah it’s insane how lucky they were. Even 10-20 metres more could have been way worse
Yikes, ya thats a new one. Interesting but not surprising to see it snapped right at the bend in the arm after the cabin suspension. Thank god it happened so close to the ground. Metal fatigue is spooky
2008 leitner poma, so still fairly new. revy has the same model but a year older, the one at breck is 2 years older. guessing there will be some conversations between the three over the next few days
Resort ops are also probably going to be shut for the next little while too seeing as how you need to take that gondy to go anywhere on the mountain, its pretty much the only way to get to terrain there, and to their other lift higher up.
very spooky
Haven't really heard of this happening recently, but I'm just glad they didn't get any higher up on the mountain. Kinda reminds me of when that one lift started running in reverse at like crazy speeds.
there better be a thorough investigation to determine the contributing factors leading to the failure. and the findings get relayed to all other gondola carriers to raise the current safety & inspection standards
seems like theres been quite a few more mechanical lift incidents on a global level this year compared to others. maybe we are just hearing about them more
cyphers2008 leitner poma, so still fairly new. revy has the same model but a year older, the one at breck is 2 years older. guessing there will be some conversations between the three over the next few days
Kinda scary for whistler too, the whistler village gondola been operating since 1988 and is poma too. I do know they are planning to replace it soon and it has also been having more mechanical issues this season. This event will probably lead to a lot of disruptions for resorts all over the place, and a huge investigation will follow for what happened and if this is an isolated problem or not.
snormanKinda scary for whistler too, the whistler village gondola been operating since 1988 and is poma too. I do know they are planning to replace it soon and it has also been having more mechanical issues this season. This event will probably lead to a lot of disruptions for resorts all over the place, and a huge investigation will follow for what happened and if this is an isolated problem or not.
haha yeah that thing is an absolute POS. but at least it got new hangers when they upgraded the cabins a few years ago so something like this would be near impossible.
i don't think there will be disruptions outside revy, seems like it was just a crack that got missed. obviously a huge fuck up but not an engineering issue. as far as i know they don't NDT hangers, just a visual inspection so you're relying a lot on the $20/hr dude to notice something
Jesus christ, lucky it happened at that low altitude. Somebody definitely missed something on the inspection. That’s what happens when management tries to cut costs wherever they can.
Late stage capitalism babyyyy, putting profit above all else couldn’t possibly have any negative implications
Situation really is like an intrusive thought come to life though, visualized it more than a few times while crammed into the jackson and snowbird trams
K-Dot.Late stage capitalism babyyyy, putting profit above all else couldn’t possibly have any negative implications
Situation really is like an intrusive thought come to life though, visualized it more than a few times while crammed into the jackson and snowbird trams
This season I’d heard a few things from staff about how RCR spend the absolute bare minimum they think they can get away with on any kind of infrastructure investment or maintenance, including lifts.
A similar thing with a gondola cabin fall happened at Mont Sainte Anne in 2022 - another RCR managed resort.
This one could have been so much worse - that KH gondy runs high and over some gnarly terrain. Thoughts with the evacuation crew who will be having a long and stressful day today.
in all seriousness the failure was probably most likely to happen there anyways as the momentum leaving the terminal can cause lifts of all types to swing and in this case, maybe swung a bit and the arm snapped. Usually its a failure in the grips and the whole thing comes off… thats wild.
The failure point makes no sense to me. It's not like a wear item failed. When I first heard this I thought the grip would have failed. That steel tube hanger should never fail even after a 100 years of operation. Especially with zero rust at the failure point
doing some napkin engineering. Assuming that is 3" diameter tube, 1/4" wall, made of the weakest grade of mild steel with a tensile yeild stress of 30,000psi gives a max tensile load on that hanger of 65,000Lb! which is a factor of safety of like 20x the expected load from the gondola+passengers. And the real hanger is using a much stronger grade of steel than my calculations.
I don't even think this should have been caught in the resort's lift maintenance inspection because that item is assumed so strong it never fails. This was a failure of the manufacture. And realistically it's the fault of Poma's steel supplier
Bit of background - I work for RCR (not KH though), and while yes, they skimp on so many things - including staff pay - not safety. They legally cannot skimp on safety. There are teams of millwrights at all resorts that are actually paid quite well for ski industry jobs, and are on every day, 365 a year. As deadhead said, this is an ultra unusual break, in a spot that should never happen, so it is not surprising it may not have been found. It also makes sense it broke where it did, that is where it speeds up, rattles, and re clamps to the cable. Of course it is lucky it was not up high though. This is in my opinion, straight manufacturer/material defect.
TLDR I am not a Murray Edwards or RCR fan, but this was not their fault IMO
deadhead420The failure point makes no sense to me. It's not like a wear item failed. When I first heard this I thought the grip would have failed. That steel tube hanger should never fail even after a 100 years of operation. Especially with zero rust at the failure point
doing some napkin engineering. Assuming that is 3" diameter tube, 1/4" wall, made of the weakest grade of mild steel with a tensile yeild stress of 30,000psi gives a max tensile load on that hanger of 65,000Lb! which is a factor of safety of like 20x the expected load from the gondola+passengers. And the real hanger is using a much stronger grade of steel than my calculations.
I don't even think this should have been caught in the resort's lift maintenance inspection because that item is assumed so strong it never fails. This was a failure of the manufacture. And realistically it's the fault of Poma's steel supplier
what the fuck
I’m very curious to see how this is all managed. From what I’ve heard from friends that work there the gondola itself is thousands of hours over its “lifespan”, but you’re right in that piece should be rated for more hours and load than it’s taken. It’s been super windy and some of the carriages have been slamming into the terminal insanely hard but hard to say what is the root cause and who will take the final blame
cyphers2008 leitner poma, so still fairly new. revy has the same model but a year older, the one at breck is 2 years older. guessing there will be some conversations between the three over the next few days
I think it’s 2000 or 2002 ? Inside the gondys themselves the tags say manufactured 2002 on them. It was getting way up there in age and hours
SurfinCowI think it’s 2000 or 2002 ? Inside the gondys themselves the tags say manufactured 2002 on them. It was getting way up there in age and hours
Sorry, Mont Saint Anne’s gondola was built in 1989 and is still operating today. These things can operate for 60 years or more with proper maintenance. They did buy new cabins in around 2002.
Looks like it twisted and sheared off. Ive never seen anything like it…
glad someone made a post about this, I was on it when it happened. Thankfully it wasn't too high up, and all my buddies in it including myself were fine. Shit was scary tho and I have a bruised ass.
partyandBSseems like theres been quite a few more mechanical lift incidents on a global level this year compared to others. maybe we are just hearing about them more
No this has been a big year for lifts falling for sure. Never seen this many in a season
K-Dot.Late stage capitalism babyyyy, putting profit above all else couldn’t possibly have any negative implications
Situation really is like an intrusive thought come to life though, visualized it more than a few times while crammed into the jackson and snowbird trams
Idk about that for here. Shit happens. Hears rumors of Vails lift at Attitash VT this seasin being that. Like they didnt replace the grips to save money or something. Again just hearsay but seems plausible
SurfinCowI’m very curious to see how this is all managed. From what I’ve heard from friends that work there the gondola itself is thousands of hours over its “lifespan”, but you’re right in that piece should be rated for more hours and load than it’s taken. It’s been super windy and some of the carriages have been slamming into the terminal insanely hard but hard to say what is the root cause and who will take the final blame
It's not even at a weld though. Shit's kinda baffling
isthiscoreglad someone made a post about this, I was on it when it happened. Thankfully it wasn't too high up, and all my buddies in it including myself were fine. Shit was scary tho and I have a bruised ass.
Pardon me for being suspicious, but you were on the one that fell??? Damn
Apparently the chair at attitash fell due to low maintenance and the guy broke his back my friends were on the chair behind him
theabortionatorIdk about that for here. Shit happens. Hears rumors of Vails lift at Attitash VT this seasin being that. Like they didnt replace the grips to save money or something. Again just hearsay but seems plausible
theabortionatorIdk about that for here. Shit happens. Hears rumors of Vails lift at Attitash VT this seasin being that. Like they didnt replace the grips to save money or something. Again just hearsay but seems plausible
not unless they were falsifying records. grips rarely get replaced but they do get rebuilt every 4-5 years depending on the lift. over the summer they'll take ~1/4 of the chairs off, take the grips apart, NDT all the metal bits and replace all of the wear parts (bearings, pins, sometimes wheels) and put it back together. then they do a test where the grip is clamped to a metal bar that gets pulled until it slips and the force reading gets recorded. i forget what the minimum was but it's far higher than a fully loaded chair on even the steepest incline.
to be honest i'm not sure how you'd slack on that unless they were just writing down fake test results. detachable grips are like the #1 most scrutinized part on any lift but obviously none of that testing would catch what happened at KH. crazy stuff
-skian-Pardon me for being suspicious, but you were on the one that fell??? Damn
yeah it was like right before 9:30 n I was with 2 of my buddies and 5 other random people. It happened as soon as we left the terminal, and idk I was j chillin' on my phone and we heard this noise and then it detached.
TOAST.Member that joined in February happens to be on a gondola that fell a month later...
sorry im not a new schoolers og like u guys 😔. But no i was on it yesterday, I was really excited since we drove pretty far just for the resort to shut down (understandably)
deadhead420The failure point makes no sense to me. It's not like a wear item failed. When I first heard this I thought the grip would have failed. That steel tube hanger should never fail even after a 100 years of operation. Especially with zero rust at the failure point
doing some napkin engineering. Assuming that is 3" diameter tube, 1/4" wall, made of the weakest grade of mild steel with a tensile yeild stress of 30,000psi gives a max tensile load on that hanger of 65,000Lb! which is a factor of safety of like 20x the expected load from the gondola+passengers. And the real hanger is using a much stronger grade of steel than my calculations.
I don't even think this should have been caught in the resort's lift maintenance inspection because that item is assumed so strong it never fails. This was a failure of the manufacture. And realistically it's the fault of Poma's steel supplier
what the fuck
Completely agree it was likely a material defect with the part that led to this, but that wasn’t a tensile failure. Likely fatigue due to repeated rocking upon exit and entrance to the lift terminal each time. There would’ve been cyclical loading in both compression and tension at the defect sight. A defect could’ve significantly decreased the limit load that needed to be cycled to ultimately cause failure. The actual loads that led to this could have been comparatively quite low with the right defect and location.
At a glance it certainly is a gut punch and head scratcher why that heavy-duty tubular structural hangar was the failure point.
With hindsight maybe...death by a thousand cuts as it were. First off I do think this failed right below a bracket...but was it a weld? It looks like a tiny bracket for the door closure mechanism is immediately above the point of failure...
deadhead420The failure point makes no sense to me. It's not like a wear item failed. When I first heard this I thought the grip would have failed. That steel tube hanger should never fail even after a 100 years of operation. Especially with zero rust at the failure point
doing some napkin engineering. Assuming that is 3" diameter tube, 1/4" wall, made of the weakest grade of mild steel with a tensile yeild stress of 30,000psi gives a max tensile load on that hanger of 65,000Lb! which is a factor of safety of like 20x the expected load from the gondola+passengers. And the real hanger is using a much stronger grade of steel than my calculations.
I don't even think this should have been caught in the resort's lift maintenance inspection because that item is assumed so strong it never fails. This was a failure of the manufacture. And realistically it's the fault of Poma's steel supplier
what the fuck
Although it's hard to make it out, there is a small bracket on those hangar arms (below the grip), and I could be wrong, but it does look like the failure point is that a microscopic crack may have started there (or close to it) and propagated until it failed from fatigue (see below marked-up photo). It looks like a U-bolted door closer mechanism is around the hangar arm...each are aligned at some point...was a tiny area "scored" to mark where to line it up...could it be that a potential scoring mark may have led to the early acceleration of a fatigue crack? Does maintenance need a box of sharpies instead of whatever implement was used in it's place to mark their alignment? Proving once again the Pen is mightier than the Sword (or screwdriver or insert other metal implement).
I read somewhere else that it was Cabin #15 that went down. Some cabins are super noisy and rattle like crazy and others are more quiet...I wonder if that was one of the "noisy" cabs? I also wonder if they track that kind of thing, you'd hope a noisy cabin gets more scrutiny at service time!
Fatigue Failure and Crack Growth from Cyclical Loading are a real bitch, forces can quickly escalate into the millions of cycles, so micro-level forces, acting on a given component add-up in a hurry (with vibration frequencies that magnify the forces). There are fatigue formulas that de-rate a material's yield stress and essentially those vibes become at least on par to those classic dynamic macro-level "impact forces" we typically think of (like bounces, or cabs slamming into the station at the top, or rapid decelerations, or wind). Let alone any resonances associated when the vibrations pass thru certain frequencies. Which is why, at a glance that large arm looks 100x over-engineered as mentioned, but clearly not when it has potential to fail...which it did because it's on the ground now.
Obviously the most violent point is that initial "take-off." There the vibrations are worst in the first few metres after gripping onto the ropeway and running under the first few sets of sheave wheels on those hold-down towers...at least acoustically-speaking (and what my butt feels). Afterwards going over/under every other tower's rollers is the next harshest series of vibrations...and each tower passed, for every lap of the gondy, is going to clock-up a certain amount of "fatigue vibrations" onto the odometer for these hangars. So the life of these components can be boiled down to hours of operation fundamentally, but that depends what variables went into that lifecycle fatigue stress calculation.
Next knowing how assumptions (missing variables) are the mother of all f*ck-ups lets us shed light on a few "unknowns" and maybe we can arm-chair reverse-engineer this snafu:
1). LONG SERVICE HOURS: I would not be surprised to find out that Poma engineers didn't account for this lift running from 6am to Midnight winter and summer vs. a typical lift going 8am-5pm (or less) and only in winter! If the standard PM maintenance inspection criteria weren't customized to take this extra service into account (give or take)... I would not be surprised. Sort of a classic finger-pointing weasel-clause...RCR might camouflage some accountability so on paper it might look like they follow a legal maintenance checklist and fully comply with safety, and when the chickens come home to roost, the manufacturer will just point back to RCR's operating outside their design spec...hence nobody could really know there was a problem...right!
2). OVERLOAD: The cabin's posted load/weight rating is typically exceeded every time they load 8 passengers on a normal ski day afaik. I forget the exact number off-hand but it's about ~1400 lbs as stickered in every cabin, so with 8 people that's 175 lbs per person...including heavy powder skis+snow that's a fairly skimpy design figure. I've sat in this gondy many a day...shoulder to shoulder with 7 other guys and we are easily pushing 200+ lbs per person net all kit and kaboodle! We laugh about "safety factors" ... those fine folks that fell might not be laughing yesterday... But this one is so obviously I'm sure they crossed all the other T's and dotted all the i's to increase the design load limit to a higher operational load limit... but then just didn't print out 55 new stickers...
3). MORE LOAD: The original door baskets to hold skis were too narrow for modern 100mm+ all mountain/powder skis plus a mix of Snowboards. Today, every door has a custom extra large aluminum cage which was custom fabricated after installation and retro-fitted onto every door (2 per cabin). However it added so much weight and torque to the cabin's doors that the closer mechanisms required many hours of "farm engineering" from the ski hill millwrights to tweak them so the doors would close properly, and reliably, regardless of weather conditions...that further dents the safety factors for the above load.
4). EVEN MORE LOAD: Not to mention 8 sets of long powder skis, loaded with snow and leaning way out, has gotta add a nice lever arm to those cyclical fatigue force calculations over-and-above the likely euro-style 67mm waisted GS skis assumed on the stock doors...I'm just guessing but what inputs were used...they didn't likely exceed what the stock ski baskets were designed to hold is all you can say!
5). EXTRA BANGING: The top station is rumored to be out of alignment from day one, it's off by a few mm (or more). Rumor has it original owner Ballast Nedam installed that station instead of Poma...they are a construction company but their surveying wasn't millimeter accurate enough in this case the rumour goes. So at every revolution it has those cabins landing hard and slamming each time, adding-on a huge torqueing/moment-force onto those hangar arms that probably isn't accounted for in that PM plan. But... rumours...
6). COLD service. Operating the lift in severe cold can really shorten mechanical component's life too (especially the deratings in those fatigue equations). Lately, like past 5-10 years, that Columbia Valley has had periods of extremely low temps below seasonal averages. I can only recall 1 or 2 days they actually stopped spinning lifts due to the cold. Because on -25C days that gondy still spins...when maybe it shouldn't. They stop it at -30C or is it -27C? We did have a cold spell a few weeks back...and this latest storm cycle was much heavier snow and lots of it was stuck to the outside of the cabs.
I would be curious if that little bracket above the failure is an inspection point for their NDT program, like you'd expect some inspection around that elbow area of the hangar...it certainly will be now if it wasn't before! Perhaps they'll learn they need to unbolt that bracket to properly check the entire hangar's elbow...sort of metaphorically failing to "roll-up up your sleeves" before starting!
I think it will be over a year before we ever see a report from TechnicalSafetyBC about this incident. But it could be faster, when the Squamish gondy was cut down their report was authored in just shy of 2 months. I agree there are laws that govern safety, and very unlikely RCR would not be in compliance as -skian- said. But basic compliance is one thing, then there's just the basic rotten attitude within sick human corporations. You can't hang it all onto a single owner, as loathsome as he may really be and certainly gets tarnished verbally like a bogeyman. Despite that each person in that RCR organization has the choice to either contribute to the crappy attitude, or rise above it; sadly it's typically a race to the bottom for everyone...but who knows...you don't know what you don't know...you're not going to get a SpaceX technician working there at any rate.
Hard to say if this incident was preventable or not, but it's not a novel method of failure (fatigue stress cracking fundamentally associated with long service life and punctuated by a single violent overload situation). The cabin that fell was apparently filled with 8 large men. I'd like to think there was a way to detect this in advance of catastrophic failure. But it's a Preventative Maintenance problem fundamentally, so ahead of specific extra PM procedures, it's a searching for a needle in the haystack problem. Word on the street is the RCR leader has a penchant for running things until they break to keep PM to a minimum. So this incident is quite on brand for them. Kicking Horse PR even gave Home Owners a presentation this Holiday season that was proud of how they had reduced maintenance related expenditures (or some such) last year. If you were taking bets on a root cause, well the clock was ticking and every hangar's number will come due at some point & the runway on that time limit was clearly & seriously under-estimated (see above factors).
To a lay person this seems like a lightning-strike kind of anomaly; but it's a well understood phenomena in aviation. But despite that, it's one that is still just as difficult to quantify, and more so in a ropeway installation vs. a plane that is mass-produced. I doubt there is a detailed model of this specific installation. 747s are made by the hundreds, and each is kind of the same, so it's better engineered and more stones are "turned over" to quantify fatigue and service life. There's only one Golden Eagle Express Gondy, and its at Kicking Horse; so you could probably fill a huge volume with the amount of unknown unknowns for this ropeway. Hopefully we'll see some Poma-Leitner big wigs or technicians on site in the near future. I'd like to see some active data acquisition of the vibrations and acoustics turn the loudest cab here into a scientific study.
It'll be telling how quickly they return this lift into service again.
ChuckWallSkiAt a glance it certainly is a gut punch and head scratcher why that heavy-duty tubular structural hangar was the failure point.
With hindsight maybe...death by a thousand cuts as it were. First off I do think this failed right below a bracket...but was it a weld? It looks like a tiny bracket for the door closure mechanism is immediately above the point of failure...
Although it's hard to make it out, there is a small bracket on those hangar arms (below the grip), and I could be wrong, but it does look like the failure point is that a microscopic crack may have started there (or close to it) and propagated until it failed from fatigue (see below marked-up photo). It looks like a U-bolted door closer mechanism is around the hangar arm...each are aligned at some point...was a tiny area "scored" to mark where to line it up...could it be that a potential scoring mark may have led to the early acceleration of a fatigue crack? Does maintenance need a box of sharpies instead of whatever implement was used in it's place to mark their alignment? Proving once again the Pen is mightier than the Sword (or screwdriver or insert other metal implement).
I read somewhere else that it was Cabin #15 that went down. Some cabins are super noisy and rattle like crazy and others are more quiet...I wonder if that was one of the "noisy" cabs? I also wonder if they track that kind of thing, you'd hope a noisy cabin gets more scrutiny at service time!
Fatigue Failure and Crack Growth from Cyclical Loading are a real bitch, forces can quickly escalate into the millions of cycles, so micro-level forces, acting on a given component add-up in a hurry (with vibration frequencies that magnify the forces). There are fatigue formulas that de-rate a material's yield stress and essentially those vibes become at least on par to those classic dynamic macro-level "impact forces" we typically think of (like bounces, or cabs slamming into the station at the top, or rapid decelerations, or wind). Let alone any resonances associated when the vibrations pass thru certain frequencies. Which is why, at a glance that large arm looks 100x over-engineered as mentioned, but clearly not when it has potential to fail...which it did because it's on the ground now.
Obviously the most violent point is that initial "take-off." There the vibrations are worst in the first few metres after gripping onto the ropeway and running under the first few sets of sheave wheels on those hold-down towers...at least acoustically-speaking (and what my butt feels). Afterwards going over/under every other tower's rollers is the next harshest series of vibrations...and each tower passed, for every lap of the gondy, is going to clock-up a certain amount of "fatigue vibrations" onto the odometer for these hangars. So the life of these components can be boiled down to hours of operation fundamentally, but that depends what variables went into that lifecycle fatigue stress calculation.
Next knowing how assumptions (missing variables) are the mother of all f*ck-ups lets us shed light on a few "unknowns" and maybe we can arm-chair reverse-engineer this snafu:
1). LONG SERVICE HOURS: I would not be surprised to find out that Poma engineers didn't account for this lift running from 6am to Midnight winter and summer vs. a typical lift going 8am-5pm (or less) and only in winter! If the standard PM maintenance inspection criteria weren't customized to take this extra service into account (give or take)... I would not be surprised. Sort of a classic finger-pointing weasel-clause...RCR might camouflage some accountability so on paper it might look like they follow a legal maintenance checklist and fully comply with safety, and when the chickens come home to roost, the manufacturer will just point back to RCR's operating outside their design spec...hence nobody could really know there was a problem...right!
2). OVERLOAD: The cabin's posted load/weight rating is typically exceeded every time they load 8 passengers on a normal ski day afaik. I forget the exact number off-hand but it's about ~1400 lbs as stickered in every cabin, so with 8 people that's 175 lbs per person...including heavy powder skis+snow that's a fairly skimpy design figure. I've sat in this gondy many a day...shoulder to shoulder with 7 other guys and we are easily pushing 200+ lbs per person net all kit and kaboodle! We laugh about "safety factors" ... those fine folks that fell might not be laughing yesterday... But this one is so obviously I'm sure they crossed all the other T's and dotted all the i's to increase the design load limit to a higher operational load limit... but then just didn't print out 55 new stickers...
3). MORE LOAD: The original door baskets to hold skis were too narrow for modern 100mm+ all mountain/powder skis plus a mix of Snowboards. Today, every door has a custom extra large aluminum cage which was custom fabricated after installation and retro-fitted onto every door (2 per cabin). However it added so much weight and torque to the cabin's doors that the closer mechanisms required many hours of "farm engineering" from the ski hill millwrights to tweak them so the doors would close properly, and reliably, regardless of weather conditions...that further dents the safety factors for the above load.
4). EVEN MORE LOAD: Not to mention 8 sets of long powder skis, loaded with snow and leaning way out, has gotta add a nice lever arm to those cyclical fatigue force calculations over-and-above the likely euro-style 67mm waisted GS skis assumed on the stock doors...I'm just guessing but what inputs were used...they didn't likely exceed what the stock ski baskets were designed to hold is all you can say!
5). EXTRA BANGING: The top station is rumored to be out of alignment from day one, it's off by a few mm (or more). Rumor has it original owner Ballast Nedam installed that station instead of Poma...they are a construction company but their surveying wasn't millimeter accurate enough in this case the rumour goes. So at every revolution it has those cabins landing hard and slamming each time, adding-on a huge torqueing/moment-force onto those hangar arms that probably isn't accounted for in that PM plan. But... rumours...
6). COLD service. Operating the lift in severe cold can really shorten mechanical component's life too (especially the deratings in those fatigue equations). Lately, like past 5-10 years, that Columbia Valley has had periods of extremely low temps below seasonal averages. I can only recall 1 or 2 days they actually stopped spinning lifts due to the cold. Because on -25C days that gondy still spins...when maybe it shouldn't. They stop it at -30C or is it -27C? We did have a cold spell a few weeks back...and this latest storm cycle was much heavier snow and lots of it was stuck to the outside of the cabs.
I would be curious if that little bracket above the failure is an inspection point for their NDT program, like you'd expect some inspection around that elbow area of the hangar...it certainly will be now if it wasn't before! Perhaps they'll learn they need to unbolt that bracket to properly check the entire hangar's elbow...sort of metaphorically failing to "roll-up up your sleeves" before starting!
I think it will be over a year before we ever see a report from TechnicalSafetyBC about this incident. But it could be faster, when the Squamish gondy was cut down their report was authored in just shy of 2 months. I agree there are laws that govern safety, and very unlikely RCR would not be in compliance as -skian- said. But basic compliance is one thing, then there's just the basic rotten attitude within sick human corporations. You can't hang it all onto a single owner, as loathsome as he may really be and certainly gets tarnished verbally like a bogeyman. Despite that each person in that RCR organization has the choice to either contribute to the crappy attitude, or rise above it; sadly it's typically a race to the bottom for everyone...but who knows...you don't know what you don't know...you're not going to get a SpaceX technician working there at any rate.
Hard to say if this incident was preventable or not, but it's not a novel method of failure (fatigue stress cracking fundamentally associated with long service life and punctuated by a single violent overload situation). The cabin that fell was apparently filled with 8 large men. I'd like to think there was a way to detect this in advance of catastrophic failure. But it's a Preventative Maintenance problem fundamentally, so ahead of specific extra PM procedures, it's a searching for a needle in the haystack problem. Word on the street is the RCR leader has a penchant for running things until they break to keep PM to a minimum. So this incident is quite on brand for them. Kicking Horse PR even gave Home Owners a presentation this Holiday season that was proud of how they had reduced maintenance related expenditures (or some such) last year. If you were taking bets on a root cause, well the clock was ticking and every hangar's number will come due at some point & the runway on that time limit was clearly & seriously under-estimated (see above factors).
To a lay person this seems like a lightning-strike kind of anomaly; but it's a well understood phenomena in aviation. But despite that, it's one that is still just as difficult to quantify, and more so in a ropeway installation vs. a plane that is mass-produced. I doubt there is a detailed model of this specific installation. 747s are made by the hundreds, and each is kind of the same, so it's better engineered and more stones are "turned over" to quantify fatigue and service life. There's only one Golden Eagle Express Gondy, and its at Kicking Horse; so you could probably fill a huge volume with the amount of unknown unknowns for this ropeway. Hopefully we'll see some Poma-Leitner big wigs or technicians on site in the near future. I'd like to see some active data acquisition of the vibrations and acoustics turn the loudest cab here into a scientific study.
It'll be telling how quickly they return this lift into service again.
This is a stellar post - really appreciate the detail you went in to.
ChuckWallSkiAt a glance it certainly is a gut punch and head scratcher why that heavy-duty tubular structural hangar was the failure point.
With hindsight maybe...death by a thousand cuts as it were. First off I do think this failed right below a bracket...but was it a weld? It looks like a tiny bracket for the door closure mechanism is immediately above the point of failure...
Although it's hard to make it out, there is a small bracket on those hangar arms (below the grip), and I could be wrong, but it does look like the failure point is that a microscopic crack may have started there (or close to it) and propagated until it failed from fatigue (see below marked-up photo). It looks like a U-bolted door closer mechanism is around the hangar arm...each are aligned at some point...was a tiny area "scored" to mark where to line it up...could it be that a potential scoring mark may have led to the early acceleration of a fatigue crack? Does maintenance need a box of sharpies instead of whatever implement was used in it's place to mark their alignment? Proving once again the Pen is mightier than the Sword (or screwdriver or insert other metal implement).
I read somewhere else that it was Cabin #15 that went down. Some cabins are super noisy and rattle like crazy and others are more quiet...I wonder if that was one of the "noisy" cabs? I also wonder if they track that kind of thing, you'd hope a noisy cabin gets more scrutiny at service time!
Fatigue Failure and Crack Growth from Cyclical Loading are a real bitch, forces can quickly escalate into the millions of cycles, so micro-level forces, acting on a given component add-up in a hurry (with vibration frequencies that magnify the forces). There are fatigue formulas that de-rate a material's yield stress and essentially those vibes become at least on par to those classic dynamic macro-level "impact forces" we typically think of (like bounces, or cabs slamming into the station at the top, or rapid decelerations, or wind). Let alone any resonances associated when the vibrations pass thru certain frequencies. Which is why, at a glance that large arm looks 100x over-engineered as mentioned, but clearly not when it has potential to fail...which it did because it's on the ground now.
Obviously the most violent point is that initial "take-off." There the vibrations are worst in the first few metres after gripping onto the ropeway and running under the first few sets of sheave wheels on those hold-down towers...at least acoustically-speaking (and what my butt feels). Afterwards going over/under every other tower's rollers is the next harshest series of vibrations...and each tower passed, for every lap of the gondy, is going to clock-up a certain amount of "fatigue vibrations" onto the odometer for these hangars. So the life of these components can be boiled down to hours of operation fundamentally, but that depends what variables went into that lifecycle fatigue stress calculation.
Next knowing how assumptions (missing variables) are the mother of all f*ck-ups lets us shed light on a few "unknowns" and maybe we can arm-chair reverse-engineer this snafu:
1). LONG SERVICE HOURS: I would not be surprised to find out that Poma engineers didn't account for this lift running from 6am to Midnight winter and summer vs. a typical lift going 8am-5pm (or less) and only in winter! If the standard PM maintenance inspection criteria weren't customized to take this extra service into account (give or take)... I would not be surprised. Sort of a classic finger-pointing weasel-clause...RCR might camouflage some accountability so on paper it might look like they follow a legal maintenance checklist and fully comply with safety, and when the chickens come home to roost, the manufacturer will just point back to RCR's operating outside their design spec...hence nobody could really know there was a problem...right!
2). OVERLOAD: The cabin's posted load/weight rating is typically exceeded every time they load 8 passengers on a normal ski day afaik. I forget the exact number off-hand but it's about ~1400 lbs as stickered in every cabin, so with 8 people that's 175 lbs per person...including heavy powder skis+snow that's a fairly skimpy design figure. I've sat in this gondy many a day...shoulder to shoulder with 7 other guys and we are easily pushing 200+ lbs per person net all kit and kaboodle! We laugh about "safety factors" ... those fine folks that fell might not be laughing yesterday... But this one is so obviously I'm sure they crossed all the other T's and dotted all the i's to increase the design load limit to a higher operational load limit... but then just didn't print out 55 new stickers...
3). MORE LOAD: The original door baskets to hold skis were too narrow for modern 100mm+ all mountain/powder skis plus a mix of Snowboards. Today, every door has a custom extra large aluminum cage which was custom fabricated after installation and retro-fitted onto every door (2 per cabin). However it added so much weight and torque to the cabin's doors that the closer mechanisms required many hours of "farm engineering" from the ski hill millwrights to tweak them so the doors would close properly, and reliably, regardless of weather conditions...that further dents the safety factors for the above load.
4). EVEN MORE LOAD: Not to mention 8 sets of long powder skis, loaded with snow and leaning way out, has gotta add a nice lever arm to those cyclical fatigue force calculations over-and-above the likely euro-style 67mm waisted GS skis assumed on the stock doors...I'm just guessing but what inputs were used...they didn't likely exceed what the stock ski baskets were designed to hold is all you can say!
5). EXTRA BANGING: The top station is rumored to be out of alignment from day one, it's off by a few mm (or more). Rumor has it original owner Ballast Nedam installed that station instead of Poma...they are a construction company but their surveying wasn't millimeter accurate enough in this case the rumour goes. So at every revolution it has those cabins landing hard and slamming each time, adding-on a huge torqueing/moment-force onto those hangar arms that probably isn't accounted for in that PM plan. But... rumours...
6). COLD service. Operating the lift in severe cold can really shorten mechanical component's life too (especially the deratings in those fatigue equations). Lately, like past 5-10 years, that Columbia Valley has had periods of extremely low temps below seasonal averages. I can only recall 1 or 2 days they actually stopped spinning lifts due to the cold. Because on -25C days that gondy still spins...when maybe it shouldn't. They stop it at -30C or is it -27C? We did have a cold spell a few weeks back...and this latest storm cycle was much heavier snow and lots of it was stuck to the outside of the cabs.
I would be curious if that little bracket above the failure is an inspection point for their NDT program, like you'd expect some inspection around that elbow area of the hangar...it certainly will be now if it wasn't before! Perhaps they'll learn they need to unbolt that bracket to properly check the entire hangar's elbow...sort of metaphorically failing to "roll-up up your sleeves" before starting!
I think it will be over a year before we ever see a report from TechnicalSafetyBC about this incident. But it could be faster, when the Squamish gondy was cut down their report was authored in just shy of 2 months. I agree there are laws that govern safety, and very unlikely RCR would not be in compliance as -skian- said. But basic compliance is one thing, then there's just the basic rotten attitude within sick human corporations. You can't hang it all onto a single owner, as loathsome as he may really be and certainly gets tarnished verbally like a bogeyman. Despite that each person in that RCR organization has the choice to either contribute to the crappy attitude, or rise above it; sadly it's typically a race to the bottom for everyone...but who knows...you don't know what you don't know...you're not going to get a SpaceX technician working there at any rate.
Hard to say if this incident was preventable or not, but it's not a novel method of failure (fatigue stress cracking fundamentally associated with long service life and punctuated by a single violent overload situation). The cabin that fell was apparently filled with 8 large men. I'd like to think there was a way to detect this in advance of catastrophic failure. But it's a Preventative Maintenance problem fundamentally, so ahead of specific extra PM procedures, it's a searching for a needle in the haystack problem. Word on the street is the RCR leader has a penchant for running things until they break to keep PM to a minimum. So this incident is quite on brand for them. Kicking Horse PR even gave Home Owners a presentation this Holiday season that was proud of how they had reduced maintenance related expenditures (or some such) last year. If you were taking bets on a root cause, well the clock was ticking and every hangar's number will come due at some point & the runway on that time limit was clearly & seriously under-estimated (see above factors).
To a lay person this seems like a lightning-strike kind of anomaly; but it's a well understood phenomena in aviation. But despite that, it's one that is still just as difficult to quantify, and more so in a ropeway installation vs. a plane that is mass-produced. I doubt there is a detailed model of this specific installation. 747s are made by the hundreds, and each is kind of the same, so it's better engineered and more stones are "turned over" to quantify fatigue and service life. There's only one Golden Eagle Express Gondy, and its at Kicking Horse; so you could probably fill a huge volume with the amount of unknown unknowns for this ropeway. Hopefully we'll see some Poma-Leitner big wigs or technicians on site in the near future. I'd like to see some active data acquisition of the vibrations and acoustics turn the loudest cab here into a scientific study.
It'll be telling how quickly they return this lift into service again.
great post. to clarify the door mechanism is not welded/bolted at the bottom as it needs to be adjusted to contact the rail correctly. the lowest point of attachment is that U bolt about halfway up the bracket, so a good 16" or so away from the failure. idk about KH but where i worked we wouldn't scribe anything like that to mark it, just a paint pen usually, for bolted connections on grips and towers and stuff we would use that anti tamper goo. we didn't NDT any hangers but i do remember doing a visual check on a bunch of chair bails which is how we found a crack on one of them and removed it from service.
it's understandable but frustrating that reports on stuff like this never get shared publicly (at least in the US), the resorts will exchange info on common failure points and possible retrofits but i never saw a memo that dove into the root cause. for something like this we would get something that said "possible material fatigue area on poma omega gondola hangers, check and advise" but it wouldn't be called out as a material strength vs. engineering issue as that was up to the tramway board to decide.
the rocker bar that snapped on the WP gondola only took it out of service for a couple days. make of that what you will...
