It might seem like they should have more redundancy - one cable broke, then a second, and just a week later the whole thing falls apart - but for structures held in place by tension it doesn't work like that.
A bicycle wheel has redundant spokes: you could design a wheel with 66% of the typical number of spokes and it would work OK. But if you do break a spoke, the wheel will start deforming straight away. If you can't replace the spoke, one piece of advice is to loosen the spoke directly opposite the broken one to even out the distribution of force.
This is not a matter of incompetence. They even had auxiliary cables installed some time ago, one of these was the first to fail.
All well-known best practices don't matter if structures cannot be maintained because the governing bodies deny the necessary funding for maintenance/repairs/operation.
Well, there was a bit of incompetence. The auxiliary cable was almost certainly installed incorrectly and the failure mode that occurred (cable slipped out of its socket) would not have happened if best practices were followed.
But it was installed on the cheap: if they'd had more money they would likely have paid for more diligent engineers. After all, they built it pretty well the first time round. So at some level, yeah, the root cause is a lack of funds.
Where? What evidence do you have for such a claim?
>The auxiliary cable was almost certainly installed incorrectly
Are you almost certain? How do you know? What stopped you from being completely certain?
>and the failure mode that occurred (cable slipped out of its socket) would not have happened if best practices were followed.
Are you a radio observatory specialist? Please share! Looking at your submission and comment history, you don't appear to have any special expertise at all. Curious where your very specific and definite pronouncements arise from.
>But it was installed on the cheap
Again: What's your evidence for this claim? And inferring this from historical under-funding isn't a satisfactory answer.
>So at some level, yeah, the root cause is a lack of funds.
Kind of strange to make all of those claims above and then come out and just plainly state this at the conclusion.
You've made lots of claims and I think you're just talking out of your ass. If that's the case, your comments are shameful and inappropriate.
Not to defend incompetence, but could the design have made it a bit unwieldy with the 900 (US) ton receiver housing the array of focusing lenses/mirrors? Is it common enough to suspend something that massive from so few points?
The only comparison I know is the FAST which opted to actively deform the dish itself for focusing rather than suspend such a heavy receiver.
The original platform didn't include the Gregorian dome. The auxiliary cables were added in the mid 90s during a major upgrade that included the dome, adding a considerable amount of weight.
The choices were made based on funding and ability. The main platform, towers, and reflector was designed and constructed in 1960, long before our computing capabilities could have even conceived of being able to accurately deform the surface. Heck, the reason the dome is so massive is that it holds a secondary and tertiary reflector to convert the focal line (an artifact of the primary reflector being a spheroid instead of a parabola) into a focal point.
Also, the 30-ton platform in FAST is the main limitation preventing FAST from being able to perform planetary radar science. It is too small and cannot support the weight necessary for a radar system of sufficient capacity.
In lots of telescope designs, the sensor is behind the dish. The part in front of the dish is only a reflector. Done that way, weight of a transmitter doesn't matter.
Around 5 years ago there was talk about shutting this facility down. So yah, it was knowingly given up, but it wasn't just a short term thought, this was decades of administrators all saying the same thing.
A bicycle wheel has redundant spokes: you could design a wheel with 66% of the typical number of spokes and it would work OK. But if you do break a spoke, the wheel will start deforming straight away. If you can't replace the spoke, one piece of advice is to loosen the spoke directly opposite the broken one to even out the distribution of force.