That is rather a bizarre thing to say. If you want to use YouTube for your statistical analysis, try replacing 'crane collapses' with 'car crashes' or 'plane crashes' in your search. Compare and contrast results.
A compilation video of many different types of crane, taken over a period of many years, in numerous countries all with differing legal frameworks, different enforcement policies and different cultural attitudes does not provide meaningful data.
I would imagine those selecting them are only concerned with the cheapest way possible to build whatever they are building. These cranes are everywhere now, was watching one operate out of the window in hospital for a few weeks, the speed the job was progressing was very impressive operatives on the ground working away like ants. But the same work was compleated for years without the big cranes just lots more men and time into the job.Tower cranes aren't my forte, but I wonder if anyone involved with the location of them looks at the "worst case scenario"?
It's not rocket science to realise that it's a gravity defying structure that's bolted to the floor, and it "could" go horribly wrong.
I would imagine those selecting them are only concerned with the cheapest way possible to build whatever they are building. These cranes are everywhere now, was watching one operate out of the window in hospital for a few weeks, the speed the job was progressing was very impressive operatives on the ground working away like ants. But the same work was compleated for years without the big cranes just lots more men and time into the job.
who built these great edifices using basic tools, plumb lines, and rope blocks.
Funnily enough, as I wander my weary way around this green and pleasant land, I love looking at churches and cathedrals. I'm not in the slightest bit religious, but I marvel at the craftsmanship of these structures.
It occurs to me quite often that I honestly don't think it would be possible to build something of that scale these days. I was in Preston a while back, within spitting distance of the church of Saint Walburge. The spire is over 300 feet high and is truly magnificent, but can you imagine the risk assessments that would have to be carried out to build that nowadays?
I regularly doff my metaphorical cap to the folk of yesteryear who built these great edifices using basic tools, plumb lines, and rope blocks.
Is there a reason why they now seem to mainly use Luffing jibs, it always used to be the T type of crane (not sure of its correct name).
Other type is known as saddle jib. Luffers are used a lot now in city sites as there are issue with overflying permissions of adjoining properties.
Saddle jibs have a long back end and fixed length front end, so if you have multiple cranes on a site, you either have to stack them so one overflies the other or put them far enough apart so they cannot crash into each other (leaving part of your site not reachable).
A lot of sites use what is called a SMIE system (https://www.en.smie.com/anticollision), which is a computer which can be set to limit the crane's movement (so you cannot jib out fully when you are facing the railway, but you can do so when facing away). It can also be used on multi-crane sites to stop them crashing into each other. This also means the luffers can all be the same height (and you only need a mobile to erect the first one; the first then erects the second and so on).
...The set up was too far out of reach for my 25 metre reach hiab, so the main contractor hired in a mobile Leibherr tower crane...
Latest update, that looks a heavy load ?
https://www.theconstructionindex.co.uk/news/view/woman-killed-in-london-tower-crane-collapse
...We in the general public will never know the full truth behind it as we are not in the loop...