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Comment by scrumper | Hacker News Reader

The general tone here seems to be against the effort, but separate the circus from the ringmaster and there is a lot to like here.

Having a manned, very high altitude, very fast research plane is undoubtedly useful for all sorts of development purposes.

But more than that, we are as a civilization doing a bad job of preserving cutting edge expertise from the past. We keep letting entire areas of engineering and technology die out without really trying to preserve them even though we know at some point they will come in useful. The skills, processes, even institutional confidence developed in just trying to get an SR-71 flying again will teach us a lot about resurrecting other such dead ends. Aerospace in particular is full of them. That will, for sure, get us out of trouble or speed up something we need at some unknown point in the future. I'd think of it more as developing a general capability than the world's most expensive vintage aircraft hobby.

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Look, I'm certified as the world's biggest SR-71 fan. As a kid, I saw it fly a number of times, got to see it up close, and had a family member who worked as an engineer on the program. I believe it may have even been this Blackbird, 844. It impacted me so much that I later went on to work on my own black and other military aircraft.

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.

Hopefully it won’t be leaking fuel anymore with modern engines

IIRC the fuel leaks on the ground were because the sheet metal was all fit rather loosely to allow for expansion in flight. At the speeds it would fly, the skin got quite hot.

But it is the fuselage gaps which was leaking, not the engines. After the elastomer filler broke down due to heat cycling. They needed the elastomer because the fuselage was heating up during flight which made it expand.

I'm sure we could "fix" it. But changing the engines doesn't seem to be the right way to achieve that.

You'd probably be using some mix of better turbofan/turbojet engines along with ramjets/scramjets and 50-60 years of materials sciences advances. So, yes.

Don't underestimate the J-58. This is as much if an extraordinary engineering feat as the SR itself.

I respect the J58's place in history, but it has no place in modern aviation. The ideas behind it still remain relevant, but the implementation is long, long outdated. I think it could be redesigned and reimplemented for cheaper that it would cost to resurrect and maintain the original J58.

Show me the UFO or it never happened!

I never saw extraterrestrial technology or any indication of extraterrestrials existing, other than gag stuff in hangars.

All the aerospace technology I've ever worked with or heard of has a pretty clear (human) engineering lineage. None of the planes you've seen or heard of, or parts thereof, are based on extraterrestrial technology.

Trump literally used it as a setup for his stupid Aliens == illegal aliens schtick.

> My hope is that if they're going to resurrect the Blackbird, they'll at least retrofit modern engines into the thing.

Question for people who actually make the engines: is this idea feasible? Like, at all?

I always imagined a plane's engines to be very tightly coupled to its electrics. In my mind, even if the wire harnesses somehow lined up right, the signals inside would be talking totally different languages.

There's standards for signaling like this. One being MIL-STD-1553. Another being ARINC. And you're now seeing a lot more Ethernet and such.

Normally, the engine itself uses proprietary signaling for its systems internally, but will present a standardized interface to the avionics.

https://en.wikipedia.org/wiki/MIL-STD-1553

Some quick wikipedia surfing suggests the SR-71 was built at least 7 years before MIL-STD-1553 was introduced. Wikipedia says 1966 for the Blackbird, and 1973 for MIL-STD-1553.

Granted, plenty of de facto standards exist long before they're codified into a formal document. So maybe the Blackbird actually does use it, or something close enough for a dinky little converter box to do the job.

According to that Wikipedia page, out of the first 6 jets to officially use MIL-STD-1553, only one of them was a Lockheed product. That single Lockheed product was the P-3C, which was a retrofitted version of a plane Lockheed started making more than a decade earlier. To me, that suggests that, even if MIL-STD-1553 existed as a de facto standard at the time of the SR-71's contstruction, Lockheed probably wasn't using it yet.

All speculation, obviously. But the timeline leaves me with doubts.

It is worth noting that MIL-STD-1553 can and has been retrofitted into multiple aircraft that were manufactured decades before it existed.

The two things that make or break an airplane are the engines and airframe. Everything else can be swapped out. As long as the airframe can support the engine, structurally and aerodynamically speaking, there are no issues. Wiring and avionics can all be easily replaced. The control systems for the plane can be reworked too.

GP is correct, this is a plane designed almost pre CFD, a clean sheet design would go much further than this. They are missing out on half a century of material science advances.

The control "computer" for the engines of the SR-71 is hydraulic, not electronic. Some of the parts of this aircraft reach temperatures beyond what current semiconductors can cope with.

If you watch a YouTube on the J-58 engines that go into this plane, you will find out that it behaves like a jet at "low" speed (like Mach 1 or below) while at Mach 3 it behaves like a ramjet. There's no other aircraft engine that does this.

You might be interested in the GE RTA :-)

https://ntrs.nasa.gov/citations/20050196667

The spirit of what you say about the J-58 is true -- it does work like that but it is still "just" an afterburning turbojet.

I personally think the path forward is a turbine -> ramjet -> scramjet architecture for an aircraft that goes zero to hypersonic.

> 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.

Came here to say this is exactly my guess.

FWIW I think it's almost always a good idea to keep at least one example of any plane flying, just out of simple cultural principle (I feel this way about the Avro Vulcan and I think it's really sad that none can do more than taxi anymore) so I am not sure it's stupid for them to ask, but I can see why keeping an SR-71 in any kind of functional condition might be implausible.

I would guess this is not a serious project to get it flying, but more a recognition that it will take more than two years to do it, could be cancelled at the two year mark without really wasting vast amounts of money, and ensures some very easy, regularly replenishable goodwill from the man who thinks the USA has planes that are literally invisible.

There is precedent, after all: his insistence on a return to steam launchers on carriers.

> somebody in the Trump campaign forced somebody at NASA to do this out of some misguided nostalgia.

Trump is a huge fan of Top Gun, there is an article he is nitpicking current aicraft carrier design and pushing them to revert to old tech steam powered hydrolic liftoffs because he thinks it looks cooler. https://nymag.com/intelligencer/article/donald-trump-navy-st...

https://www.theguardian.com/us-news/2026/aug/13/trump-aircra...

He also nitpicks where the towers should be located on aircraft carriers and wants them to look more like the ones from WWII: https://www.washingtonpost.com/national-security/2026/08/15/...

https://talkingpointsmemo.com/edblog/trump-to-order-redesign...

Bringing back the SR-71 for nostalgia/cool factor tracks reverting to steam hydraulics liftoffs and overhauling the aesthetics and tower location to look like old warships.

'nitpicking' is a weird way to describe 'expects new technology to be reliable, wants to use the tried and true technology until then'

The F-14 got sent to the boneyard because it was so much more expensive to operate than comparable aircraft. The F-14 had only one real mission: carry the Phoenix to defend the carrier from the Russian bombers. And it was a suicide mission--the sprint to launch position would not leave enough fuel to get back to the carrier.

> 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.

Why would you assume that?

Have you heard about the ‘new’ battleship plans? [https://en.wikipedia.org/wiki/Trump-class_battleship]

It would be shocking if it wasn’t what was happening - resurrecting the SR71 makes no sense, just like resurrecting the idea of a battleship. Tech has far eclipsed their usefulness.

It’s the military budget being prioritized based on boomer nostalgia, not any actual plausible fit to reality.

The Navy has been pushing for a large cruiser for literally decades now. The Trump-class is that under a different name. We're at the end of what we can cram in a hull that's nominally called a destroyer, especially if you want to host larger hypersonic strike weapons and ABM interceptors, plus the radars to manage the ABM battle.

Right but 'battleship'?

That's the same kind of silliness as calling the Russian Kirov class 'battlecruisers' in my opinion. It's not going to stand in the line of battle and exchange shells with other battleships is it?

Kirovs are the size of WWI battleships and exchange the heaviest AShM missiles made with other battlegroups, so yes?

At the end of the day the Navy is seeing Orange Man offer a them a check to build the cruiser they've wanted for decades. They'll finally have the space and power to do all kinds of things they can't pull off on a destroyer hull (even if said "destroyer" is really a cruiser in other clothing). If they have to call it a BBN or whatever to make Trump happy they'll do it.

a single hit from enemy anti shipping missles would likely blow the whole thing up.

I agree with the manipulating the nostalgia angle, the real plan just isn’t anything like an actual battleship, and the approval is also because they’re using ‘battleship’ to manipulate the nostalgia.

By the time they are ready, Trump will have long lost the ability to name anything.

The US Navy needs fewer Kirovs, Yamatos and Ticonderogas. When (not if) the US enters the Pacific theater, they will be going up against Chinese land-based strategic AShMs and potentially 50+ Type 052 destroyers. The moment the US enters any capital ship into this theater, it will be like a 21st-century Battle of Midway with hypersonics, SAR satellites and ballistic missiles.

The Trump-class is pretty clearly one of those interim study projects that only exists to fill a perceived gap in force composition. Unlike the USAF NGAD, I don't think the Trump-class will ever see the light of day, let alone a battle versus a peer-power.

There have been no battleship-versus-battleship combat since 1944. Airpower made them obsolete.

https://en.wikipedia.org/wiki/Battle_of_Leyte_Gulf

The naval terminology reflects a displacement class and use case, not a specific design.

The now-cancelled DDG(X) next-generation destroyer already had a larger displacement than a heavy cruiser. And it was cancelled for not being large enough to support its mission load-out as a modern destroyer.

The name “battleship” may be archaic but the displacement requirements for the next-generation destroyers (or whatever they are eventually called) are roughly in “light battleship” territory.

To put it another way, we were calling battleship-class ships “destroyers” for historical continuity reasons. Over time, ships in a class have become much larger but we kept the old names. Even the older Arleigh-Burke destroyers would be traditionally classified as heavy cruisers if they were commanded by a flag officer.

"Battleship" is based around big guns. What he wishes he had in his pants. In a modern situation there's simply no use case for a big gun. How do you propose to get within range?

On one side we have a battleship. $2B in current dollars for a WWII ship.

On the other side we have 10% of that value in harpoonskis.

The battleship never reaches gun range.

Naval gunfire has use against targets not worthy of a missile. But anything you're going to be shooting it at doesn't have armor to speak of.

Don’t forget thick armor. A battleship with no guns and no armor is literally no battleship at all, hah.

Because Trump has a history of it.

See this comment for a quick set of links: https://news.ycombinator.com/item?id=49910639

> 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.

Is there? High speed turbofans are still exotic technologies. Or are we doing the research with drone rockets now? I have to imagine that building a modern SR-71 replacement would be an expensive development project with little commercial prospects. The sort of thing that is extremely hard to complete in the modern political environment.

Turbofans are not exotic technologies. They are well understood, and their limitations are well understood.

Presumably, an SR-71 successor would use a mix of turbofans and ramjet/scramjet to meet their performance (speed/altitude) goals, depending on whether it would be self-sufficient or use takeoff assist from another aircraft.

Despite them being complex, high-bypass turbofan engines ARE exotic technology. There are vanishingly few countries/companies that have the expertise necessary to produce the single crystal fan blades used in the engines of these aircraft.

As far as the SR-71, its engines were turbojets that transitioned to ramjets above Mach 2ish. They required a special grade of jet fuel and a dedicated fleet of refueling aircraft.

I rather doubt an SR-71 successor would use a turbofan. The mission profile really doesn't require it. I would expect it to be a turbojet that transitions (as you said) to a ramjet and eventually a scramjet.

I would love to see the SR-71 fly again, if only from a nostalgia standpoint, but I really doubt this effort will be successful. I doubt even more that much of value can be accomplished by getting one to be flyable again that couldn't be achieved in a much more cost-effective manner via unmanned aircraft.

> Despite them being complex, high-bypass turbofan engines ARE exotic technology.

Sure, I'll concede here. I think of "exotic" as "few people/nations understand it well enough" but including the manufacture and tooling seems like a no brainer inclusion.

Edit to my comment, I meant "Despite them being common," not "Despite them being complex."

The whole of the SR-71 was built around what kind of cameras was needed to perform the mission. Modern electronics and cameras are much smaller. I would presume an unmanned plane launched from a bomber could perform the mission today.

"Make America Great Again" leans a lot into restorative nostalgia so it's unsurprising that ideas from the past are going to be presented as an idealized goal.

Please note that we are also spending money on getting F-14s flight worthy again, for no other reason than movie-brain and nostalgia.

It's literally called "The Maverick Act."

The current administration is so thoroughly enmired in nostalgia for the 20th century that I won’t be surprised when they restart production of the P-51.

perceived nostalgia, because a lot of that supposed nostalgia can't be defined or isn't actually true.

I would appreciate a solid explanation of which periods and aspects "Make America Great Again" refers to. I can think of a couple ones off the top of my head regarding technical progress, but I'm unsure whether MAGA helps or hinders that progress.

You pose an interesting theory related to "if star wars was real they would have robots fly all the planes". In that, something our own nostalgia and hubris will ultimately lead us to always mostly demand manned aircraft.

I would be willing to wager that the US already has at least one high altitude, very fast research plane that incorporates all sorts of modern materials and technology, and therefore has no particular need for an obsolete aircraft from the 1960s that was primarily designed to solve 1950s problems.

The SR-71A was a reconnaissance or spy plane that flew at high altitude where it avoid anti-air weapons of the era by flying at high altitude and at Mach ~3.

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.

Investing in the well-being of our society will severely impact our ability to mint billionaires and trillionaires.

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