We simply don't need that capability anymore. Recon of this sort is now done by satellites (at much higher resolution) and it's unclear if designated enemy states don't have or couldn't have an effective defensive system.

Now you cold have a program to develop hypersonic airframes and engines (eg scramjets) but it's way more likely that this kind of technology will be applied to cruise missiles, anti-ship missiles and so on.

Some things we don't need to maintain just to maintain them.

I'm assuming that, if this rumor is true, somebody in the Trump campaign forced somebody at NASA to do this out of some misguided nostalgia. My hope is that if they're going to resurrect the Blackbird, they'll at least retrofit modern engines into the thing.

But there are much more modern, cost-effective ways to build very-high-altitude, very-fast aircraft. I'm doubtful that going manned is the right approach. It takes a lot of weight and space to carry a person and the required life support systems. That capacity could be better utilized for more fuel and sensors.

There's better technology that's far cheaper to maintain and operate. And you could potentially get hypersonic, or at least near-hypersonic, performance.

Engineering says the juice isn't worth the squeeze. The message management hears is, "It's impossible." They respond - often correctly, if we're being fair - "But of course it's possible." Engineering instead hears them insisting it's feasible.

I bet that cycle gets cranked up to high gear in an environment like the current US administration where two-way communication is impossible because telling your boss something other than what they want to hear is tantamount to handing them a resignation letter.

This is very labour-intensive, which is why it is generally carried out in dedicated workshops, with specialised equipment, and so on, by staff who have been specifically trained and do nothing else.

If you add jigs, production-specific tools, and so on, all of that has been lost and needs to be recreated: staff need to be trained, QA defined and workshops need to be reorganised. This can take decades to return to the expected standard. You can throw as much money at this sort of problem as you like without actually being able to speed things up.

Finding the drawings and dimensions is the easy part of reverse engineering a mechanical device. The real challenges lie in identifying the manufacturing processes and quality control procedures, and achieving the expected performance with an acceptable scrap rate.

If I place a monocrystalline turbine blade on your desk, you’d be able to draw up the plans for it. But that would tell you absolutely nothing about the processes required to produce a monocrystalline ingot of a nickel superalloy.

Source: former mechanical engineer in the nuclear industry, managing obsolescence was one of my day-to-day tasks.

The bigger problem there is that we don't have the people any more.

The Rocketdyne F1 was the pinnacle of hand-crafted engineering, with each engine being slightly different and the people having to account for those differences during assembly. It has a whole bunch of complicated welds which require a lot of tweaking, adjusting, and literally days of welding work? Neil's got to go to the moon, so you better get to it!

Those highly-skilled highly-specialized engineers don't exist any more, and for a good reason: with CNC and robots we can achieve far superior results for a fraction of the cost. It just requires the designers to make it automation-friendly from the start. Those skilled people retired (and by now died) without a replacement, because the job had become obsolete.

So no, we literally cannot build a new Rocketdyne F1. We can design and build a better F1-like engine, though!

As far as #2 and the rest goes, I agree that with enough money you could make anything happen. However, sometimes recreating something so complex could be a "not enough money in the world" type situation. Sure, drawings and specs exist, but even on today's 3-d modelled assembly you're not typically modelling every single part to full accuracy. You have things that are off the shelf that might be a black box drop in, you have things you contract out that are built to spec. You know what you get, but not necessarily exactly how it's done. Then in your own facility there is a certain level of institutional knowledge that is not necessarily documented in such a way you can just recreate it.

Finally, one of the biggest hurdles, there's are not things that you can just throw an LLM and some engineers at. The actual trades themselves have changed so much since the time of production your only option is to call in retirees. The machinery is different now and so are the workers.

I feel like with a large budget they could definitely get an SR-71 in the air for testing and exhibition purposes, Id love to see it happen. I guess it really depends on how much was removed and destroyed when the machine was decomissioned and how much damage lack of maintenance, environmental factors and age have taken their toll. The good news is it hasn't been operated in a long long time. The bad news is it hasn't been operated in a long long time.

Source: I am a toolroom machinist at a material science lab in the aerospace and defense sector.

That's an A-12, not an SR-71

https://news.ycombinator.com/item?id=8251084

https://www.youtube.com/watch?v=Y6tqlf31YTc