How to calculate how long a large project will be delayed? How likely it will be completed at all?

Eric_the_Cerise
2025-08-12T10:23:31Z

I'm talking Really Big Projects.

NASA plans to have astronauts skinny-dipping in Shackleton Crater by 2030. Norway wants to build the first ever commercial ship tunnel, done by 2030.

That's the level I'm talking about.

And also, I'm not talking about cost overruns or resource requirements, or anything like that.

I just mean, really big, really public, engineering projects -- typically chock full of political complications -- get announced in the news, like ...

"NASA to build Super-Duper-Big Telescope on Olympus Mons, for $8B, by 2034"

-- and everyone knows it's actually going to cost 6-16x that amount, and be ready to use in the late-2040s ... assuming it gets built at all.

I want something vaguely formulaic to calculate how much and how long it will actually take NASA to build that telescope.

Back before he became universally hated, it was kind of a meme-level joke that Elon Musk was already living on Mars time, so all of his project-completion estimates had to be multiplied by 1.88 (to convert from Martian back to Earth years). The funny thing, as a rough guideline ... that was actually a pretty reliable formula.

I want something like that formula, but given a bit more thought and research, maybe some optional variables to take into account the project circumstances.

There are plenty of studies (I've been looking) that seek to identify and calculate the causes of large-project delays and cost-overruns, and how to minimize/avoid them. But I'm not trying to rein in the delays and overruns ... I just want to have a way of semi-realistically calculating, right at the start, just exactly how badly people are underestimating the timeline for building their Big Shiny New Thing.

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