How ski lifts are installed: Vail's new Chair 5 (2011) [video]
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What I mean is: pre-optimizations like that. My current cofounder and I build and run fire effects [flamethrowers] at music festivals, and every load-in/setup is a fun game of seeing what ways we can optimize our setup process. Stuff like figuring out the wrenches and tools we need to assemble a specific component, and then storing those tools with the component.
Seeing those bolts sitting on the grate like that (I think it was 4 on each side) means that somebody had the foresight to realize that it was easier to strap the bolts to the piece like that, than to have the guys assembling it carry them with them up the ladders (imagine if they forgot one, what a pain that would be).
So freaking cool.
Definitely something to keep in mind though.
As a lighting guy I saw to much stuff fall from the sky. One concert hall I worked at used a rice-paper snow effect for a Japanese show. Four years later we still had the occasional bit of rice paper glide slowly down from 100' up. It could never hurt anyone, but film/TV clients who used the hall would be screaming mad when they saw it.
Not to curb your enthusiasm or downplay the ingenuity of those builders, but the assembly process seems fairly repetitive and easier to optimize over time. I doubt they had this foresight before doing the first (ever) pole.
It's like building a really good workshop. Ideally everything is exactly where it needs to be, and in the exact order you might need it.
Another example is: my electronics assembly dreamcart (that I haven't gotten to build yet):
-18-24ga stranded wire in at least 3 different colors on spools above the worktable
-Soldering iron
-Oscilloscope
-Power supply
-Multimeter
-Strippers/side cutters [1]
-Crimpers
-Crimps/ferrules
-Network switch/ethernet cables
All of this stuff on a cart that is on casters, with a UPS that can power it so if I need to move away from an outlet I can.
I didn't figure out exactly the tools I wanted and how I wanted them arranged on my first project, but over time I figured out the exact tools I want, and where in my workspace I want them, so that I have to spend as little time as possible looking for things, or thinking about where they might be.
I think seeing the little improvements people have made is really cool. Like the bolts. It's cool because maybe the didn't figure it out on the first time.
[1]: I particularly like this one because it puts the strippers and the side cutters in the same hand, which is just closer to my optimal dream-shop/workflow: https://www.amazon.com/DA76070-KLENK-Wire-Cutter-Stripper-Sm...
http://www.kaman.com/aerosystems/solutions/air-vehicles-mro/...
https://www.youtube.com/watch?v=iEx3dJTIjww
They've also developed an unmanned version for military resupply missions:
https://www.youtube.com/watch?v=jQ4X7Y2ydS0
http://jalopnik.com/this-is-the-weirdest-dang-helicopter-i-h...
It seems that there are reasonably long period of time here when the helicopter is still connected to a tower segment when the workers are in the process of screwing bolts in. Why isn't this problematic?
The operations depicted are not uncommon on construction sites (e.g. when mounting rooftop equipment) and there are OSHA regulations for helicopter cranes. https://www.osha.gov/pls/oshaweb/owadisp.show_document?p_id=...
The use of guide cables/pins was really neat. Assuming the camera is 'real' time (it wasn't sped up for the video) it looks like about 15 seconds between starting to pull the guide cables through to the point where they have two bolts installed. So a pretty narrow window for problems, of course you wouldn't do it when it was windy out either.
Deck hand on Indian fishing trawler is more toward the dangerous end. This is pretty in the middle. Very few variables are uncontrolled here. Anything involving confined spaces and chemicals is definitely more on the dangerous end.
1. Tower segment is hanging from helicopter.
2. Tower segment is in place with pins preventing it from falling over, but can be lifted away by the helicopter.
3. Tower segment is in place with pins preventing it from falling over, and will be released if the helicopter needs to fly away.
4. Tower segment is in place, fully secured by bolts.
The key point here is that under good conditions -- and they only ever do this under good conditions! -- a few pins is all it takes to stop the tower segment from falling over, but they won't stop the helicopter from lifting it off again. Securing the tower with two dozen bolts is only necessary when you want it to stay in place during strong winds and with the added load of the lift cable + chairs.
This is due to the calculated risk of something going wrong: workers on the pole can quickly move around if the unmounted pole starts falling, similar to lumbar can quickly change position when tree falls. With helicopter however, a violent pull of attached line could probably end up with part of helicopter being chunked out of the hull.
In the event there is a risk to the helicopter due to the winch operation (such as the line becoming stuck in some tress below) - the pilot has the ability to cut the cable to ensure the helicopter is not compromised.
http://www.raf.mod.uk/rafsearchandrescue/rafcms/mediafiles/7...
You need to see it in HD to see the rope. It's called "recovery assisted landing" or sometimes "hauldown".
Ski lift installations are rare, but power line towers go up by the tens of thousands. So the power line people need a way to do this routinely and safely.
We were shown this video during our training, and our boss said with a very straight face that if she were ever on a chair that started rolling backwards, she would jump off.
The reason "rollback" can happen is because the weight of all the people is only on one side of the line, and that weight wants to come back downhill. The chair has a couple of different kinds of brakes that are supposed to prevent this, but you can see what happens when it fails / is engaged too late.
Two broken legs are better than that.
NOTE HOWEVER: Newer "Detachable" or "high-speed" chairs and gondolas are often designed to run in reverse, so don't immediately jump off one of those if it goes backwards.
I wonder if the "up and down" lifts that go down and up a valley (e.g. there is one at Alpe d'Huez) or over a ridge (e.g. the one at Val d'Isere) suffer from the same problem - even allowing for the fact that I'm pretty sure that they are modern detachables.
Until you work a chairlift they are all fun and games.. after.. well, they are serious pieces of heavy machinery.
On my first day running one I hit the stop button and then watched the chair continue for ~5 feet, which snapped a young ladies Femur clean in two about 3 feet from my face. Safe to say that was not pretty.
I've also seen countless people knocked out by them, seen full derailments (scary) but happily never seen fingers or hands go into places they shouldn't.
Also had guests fall off the chair and die.
so yeah, very serious.
> I wonder if the "up and down" lifts that go down and up a valley suffer from the same problem
My gut says yes, because when all is said and done they are moving a lot of mass from down to up, and all that mass is still only on one side.
Her snowboard was dangling and caught on the beginning of the unload ramp. About that time I hit the e-stop, though of course a many-hundred ton machine with a 1200hp drive motor is going to continue for a bit before it actually stops moving. Even with the e-stop a big heavy four-seater fixed grip will go 6-8-10 feet or so. If it wasn't my first day maybe I would have hit that button sooner.
(Side note, they make the chairs heavy on purpose so they are less susceptible to the wind.. Otherwise they blow around and hit towers. I have been sitting on a chair when it slammed sideways into a tower before. Not fun)
Her board caught in the snow and started to pull her forwards off the chair, but her arm through the slats stopped that happening, so the chair started to swing back and load up with all the forces. It got to quite an impressive angle before something gave way, and it was her femur, because it was half off the leading edge of the chair.
Obviously that was a major ski patrol incident, and I had to write witness statements and draw diagrams of the whole thing in case she tried to sue the resort within 7 years (California...)
Another day I watched a liftie raking the top ramp look up just in time for the chair to smash him right on the forehead - he was out cold for 10 minutes.
That same guy was later scooped up by the chair at the top, and the sudden weight in the chair as it went around the bull wheel caused a derailment. The haul rope (cable) came out of the bull wheel (the big wheel at the top). This is a pain in the ass to fix, especially when there is the weight of hundreds of people sitting on the haul rope. That was a full manual evacuation, which takes hours and hours of lowering people down with ropes.
Some of my best days were "saving" people from getting hit. At the bottom once you have worked 100+ days you can see an issue coming three chairs before it happens, so it's like you are Superman. Often kids would be in the worst possible place and were about to get creamed by the big heavy chair. It's not possible to hold the chair back (even if you could , maint. doesn't want us doing that, we can damage stuff) and the e-stop won't stop it in time. I hate seeing kids get hit, so I would run over and tackle them to the ground, holding them down while the chair sails over both of us. Everyone lined up would cheer. It was great fun!
Of course, we screwed around a lot too - holding on the chair and letting it drag us along the snow, sitting on the chair and waiting to be the last to jump off into the powder, trying to "hurdle" the chair as it comes towards you (which was insanely hard because you have to jump the chair, but duck the steel bar at the top)
All in all, really, really good times.
I was out in Aspen two weeks ago and we were wondering if the lifties get drug tested (never thought about it before). I said they have to, they are responsible for other people's lives and safety. My friends all said no way.
What's your experience?
Where I worked literally every single employee on the mntn smoked, so if you were a pain the neck to your boss they would ask for a drug test and you were basically fired.
In Canada, as far as I know, it never happened (I worked there a few seasons, everyone smoked)
I would say on the majority of days that other people lives and safety were in our hands, the vast majority of lifties were severely hungover and/or stoned.
Did see 2 guys jump from a chair from about 10m up onto a pretty horizontal surface - no idea what they were thinking fortunately the snow was quite deep so they just looked dazed rather than badly injured.
2:12 https://www.youtube.com/watch?v=IHsF1kRKEV0
TLDR; Spool out cable (rope), lift the end up with helicopter drape it over the sheave train (the wheels on the cross arm) pull out more rope, etc
The splice for the Vail lift is about 300 feet long apparently.
I used to play it quite a bit when it first came out.
I used to be a volunteer on an emergency lifeboat crew, we would do a lot of drills with a man on a winch and the first rule is, don't touch until he's earthed. Helicopters pick up a hell of a lot of static electricity so you normally see a small earthing line hanging below the man on the end of the line.
One time we were practicing fast recovery, the boat and the helicopter doing crew exchange at high speed. We screwed it up and the static charge blew a hole in the side of the boat!
TIL: Not everyone uses the term earthed!
Your point stands though: gondolas are probably not a great form of transport. That said, I have no idea what the speed limits would be for a gondola that was designed for speed.
http://www.curbed.com/2016/7/25/12248896/urban-gondolas-cabl... http://www.curbed.com/2016/5/19/11714678/urban-cable-austin-...
http://wdwnt.com/blog/2017/04/depth-speculation-disney-world...
While you can make a multiple stage detachable gondola, every detach point/stage is adding significantly more points of failure and complexity. There is a reason you don't see more than ~3-4 stages and that's it.
They are also very maintenance intensive and not all that reliable.
Unique geography there; the city is in a bowl, but El Alto, its main commuter suburb, is on the high plain above the rim of the bowl. There is a single road linking them, which in rush hour is jammed with minibuses.
London also has its "Emirates Air Line", which is a pointless gimmick that doesn't serve a useful route.
Fun video