SR-72: US secret hypersonic jet to allegedly break sound barrier in 2025 | Believed to be a top-secret project of the US Air Force, the SR-72 is touted to reach over 4,000 mph (6,437 kph), making i...

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SR-72: US secret hypersonic jet to allegedly break sound barrier in 2025 | Believed to be a top-secret project of the US Air Force, the SR-72 is touted to reach over 4,000 mph (6,437 kph), making i...::undefined

52

There were a lot of things we couldn’t do in an SR-71, but we were the fastest guys on the block and loved reminding our fellow aviators of this fact. People often asked us if, because of this fact, it was fun to fly the jet. Fun would not be the first word I would use to describe flying this plane. Intense, maybe. Even cerebral. But there was one day in our Sled experience when we would have to say that it was pure fun to be the fastest guys out there, at least for a moment.

It occurred when Walt and I were flying our final training sortie. We needed 100 hours in the jet to complete our training and attain Mission Ready status. Somewhere over Colorado we had passed the century mark. We had made the turn in Arizona and the jet was performing flawlessly. My gauges were wired in the front seat and we were starting to feel pretty good about ourselves, not only because we would soon be flying real missions but because we had gained a great deal of confidence in the plane in the past ten months. Ripping across the barren deserts 80,000 feet below us, I could already see the coast of California from the Arizona border. I was, finally, after many humbling months of simulators and study, ahead of the jet.

I was beginning to feel a bit sorry for Walter in the back seat. There he was, with no really good view of the incredible sights before us, tasked with monitoring four different radios. This was good practice for him for when we began flying real missions, when a priority transmission from headquarters could be vital. It had been difficult, too, for me to relinquish control of the radios, as during my entire flying career I had controlled my own transmissions. But it was part of the division of duties in this plane and I had adjusted to it. I still insisted on talking on the radio while we were on the ground, however. Walt was so good at many things, but he couldn’t match my expertise at sounding smooth on the radios, a skill that had been honed sharply with years in fighter squadrons where the slightest radio miscue was grounds for beheading. He understood that and allowed me that luxury.

Just to get a sense of what Walt had to contend with, I pulled the radio toggle switches and monitored the frequencies along with him. The predominant radio chatter was from Los Angeles Center, far below us, controlling daily traffic in their sector. While they had us on their scope (albeit briefly), we were in uncontrolled airspace and normally would not talk to them unless we needed to descend into their airspace.

We listened as the shaky voice of a lone Cessna pilot asked Center for a readout of his ground speed. Center replied: “November Charlie 175, I’m showing you at ninety knots on the ground.”

Now the thing to understand about Center controllers, was that whether they were talking to a rookie pilot in a Cessna, or to Air Force One, they always spoke in the exact same, calm, deep, professional, tone that made one feel important. I referred to it as the ” Houston Center voice.” I have always felt that after years of seeing documentaries on this country’s space program and listening to the calm and distinct voice of the Houston controllers, that all other controllers since then wanted to sound like that, and that they basically did. And it didn’t matter what sector of the country we would be flying in, it always seemed like the same guy was talking. Over the years that tone of voice had become somewhat of a comforting sound to pilots everywhere. Conversely, over the years, pilots always wanted to ensure that, when transmitting, they sounded like Chuck Yeager, or at least like John Wayne. Better to die than sound bad on the radios.

Just moments after the Cessna’s inquiry, a Twin Beech piped up on frequency, in a rather superior tone, asking for his ground speed. “I have you at one hundred and twenty-five knots of ground speed.” Boy, I thought, the Beechcraft really must think he is dazzling his Cessna brethren. Then out of the blue, a navy F-18 pilot out of NAS Lemoore came up on frequency. You knew right away it was a Navy jock because he sounded very cool on the radios. “Center, Dusty 52 ground speed check”. Before Center could reply, I’m thinking to myself, hey, Dusty 52 has a ground speed indicator in that million-dollar cockpit, so why is he asking Center for a readout? Then I got it, ol’ Dusty here is making sure that every bug smasher from Mount Whitney to the Mojave knows what true speed is. He’s the fastest dude in the valley today, and he just wants everyone to know how much fun he is having in his new Hornet. And the reply, always with that same, calm, voice, with more distinct alliteration than emotion: “Dusty 52, Center, we have you at 620 on the ground.”

And I thought to myself, is this a ripe situation, or what? As my hand instinctively reached for the mic button, I had to remind myself that Walt was in control of the radios. Still, I thought, it must be done – in mere seconds we’ll be out of the sector and the opportunity will be lost. That Hornet must die, and die now. I thought about all of our Sim training and how important it was that we developed well as a crew and knew that to jump in on the radios now would destroy the integrity of all that we had worked toward becoming. I was torn.

Somewhere, 13 miles above Arizona, there was a pilot screaming inside his space helmet. Then, I heard it. The click of the mic button from the back seat. That was the very moment that I knew Walter and I had become a crew. Very professionally, and with no emotion, Walter spoke: “Los Angeles Center, Aspen 20, can you give us a ground speed check?” There was no hesitation, and the replay came as if was an everyday request. “Aspen 20, I show you at one thousand eight hundred and forty-two knots, across the ground.”

I think it was the forty-two knots that I liked the best, so accurate and proud was Center to deliver that information without hesitation, and you just knew he was smiling. But the precise point at which I knew that Walt and I were going to be really good friends for a long time was when he keyed the mic once again to say, in his most fighter-pilot-like voice: “Ah, Center, much thanks, we’re showing closer to nineteen hundred on the money.”

For a moment Walter was a god. And we finally heard a little crack in the armor of the Houston Center voice, when L.A.came back with, “Roger that Aspen, Your equipment is probably more accurate than ours. You boys have a good one.”

It all had lasted for just moments, but in that short, memorable sprint across the southwest, the Navy had been flamed, all mortal airplanes on freq were forced to bow before the King of Speed, and more importantly, Walter and I had crossed the threshold of being a crew. A fine day’s work. We never heard another transmission on that frequency all the way to the coast.

For just one day, it truly was fun being the fastest guys out there.I’m

Every time I see this story I laugh. Thanks for posting it.

That read beautifully, must have been such a good moment. Hope you didn't catch any flack for that though?

Um, that wasn't OP's story, it's an old copypasta from Reddit. https://old.reddit.com/r/copypasta/comments/9z7923/sr71_blackbird_copypasta/

Which was in turn derived from the book "Sled Driver: Flying the World's Fastest Jet" by Brian Shul.

It might even be from before then. I could swear I saw this copypasta back on the GameFAQs message board in the early 2000's.

This is my favorite copypasta. Love that Blackbird.

Got all the way to 71 by 1966, but then 59 years to get to 72? What've those skunks been doing?

Sexually harassing cats and talking with French accents.

There was more of an attempted rape vibe going on there. Sexual harassment was just the icing. Get your Warner Brothers silliness straight.

If those cats didn't want it they wouldn't have been wearing those paint stripes. /s

This new plane is a hypersonic weapon delivery drone, barely related to the SR-71 aside from the speed it can travel.

As to the sixty years thing, satellites made spyplanes nearly entirely obsolete and traditional aircraft with stealth technology covered the remaining cases well enough that there wasn't a need for more speed. Research went into making missiles better instead, and this is designed to be a launch platform for those missiles.

Then why do we still operate the U2? SR-71 was operated all the way until 1999. Hubble was launched in 1990 so the large mirrors for spy telescopes had to have been in use well before that.

A little late to allegedly break sound barrier in 2025: https://en.wikipedia.org/wiki/Sound_barrier

Right! They used to have a commercial airliner that broke the sound barrier.

I was confused about how the article kept saying "hypersonic" without defining it. Looks like hypersonic means 5x the speed of sound.

https://www.dictionary.com/compare-words/hypersonic-vs-supersonic

It means a little bit more than that. Mach 5 at sea level is usually when the properties of air changes into a plasma. The electrons are separated from their atoms creating an electrically charged plasma that the vehicle travels through. The speed where hypersonic is defined differs at higher altitude due to the composition of the fluid it travels through. I'll have to dig up some old textbooks to get a more accurate definition though.

Source: Aerospace engineer who worked on hypersonic projects for the Air Force

EDIT: The conventional rule of thumb is to define hypersonic aerodynamics as those flows where the Mach number is greater than 5 however that is no more than a rule of thumb. Hypersonic flow is best defined where certain physical phenomena become progressively more important as the Mach number is increased. In some cases these phenomena might become important above Mach 3, in other cases they are important above Mach 7. Example phenomena:

  • Thin shock layers
  • Entropy Layer: It's a region of strong vorticity and effects boundary layer calculations
  • Viscous Interaction
  • High Temperature flows
  • Low-Density flow

I forgot to mention before the edit that the actual shape of the object traveling through the fluid also effects when the fluid becomes hypersonic due to it's interaction on the fluid (shocks, recapitulation, boundary layer interactions, etc.).

Source: Hypersonic and High-Temperature Gas Dynamics 2nd Ed. (John D. Anderson Jr.)

Thanks for delivering on that textbook, even though I don't understand most of it, it sounds cool as hell

Back when Ukraine invasion kicked off there was a lot of puffing about Russia and Chinas hypersonic capabilities, fearmongering essentially. I was a nerd bout the X projects so i knew it was all smoke. When I would say that Russia or China can't even begin to touch US hypersonic tech, this is what I mean. The US has been working on hypersonic flight for decades, before China's economic boom, and while post soviet Russia was still a baby with a destroyed economy. I would be very surprised if the have anything anywhere close to what we have.

Aren't the Russian hypersonic missiles essentially just regular ballistic missiles? I remember reading something saying that calling them hypersonic was a stretch, and they have been intercepted by standard missile defense systems which actual hypersonic missiles wouldn't be.

I think they have gliding capabilities and can maneuver but they generally follow a predictable trajectory and thats why they are able to be shot down, because if they do maneuver they lose a stupid amount of range.

I'm extremely curious what those weapon systems look like. A missile? Maybe two? 10 bricks? 5,000 ball bearings? Any object hitting anything at ~4,000 mph would do a fuckton of damage.

Why does it take one year for this plane to warm up before it breaks the sound barrier? Aren't there planes that already break the sound barrier in minutes/seconds and not take years?

I think the speed is more in regard to the capability to go into space. From what I remember, the SR71 was easily fast enough to go, but the limit was atmosphere (engines). If they could get something into space that could come back as a single unit (needing just a refuel), it could change a lot. Total speculation though, it's probably just super fast so it can go destroy other humans super good, because that's super important.

The speed of sound is roughly 750mph

This plane goes 4000mph. Thats like Mach 6 right?

Edit: looks like SR71 still holds the record for now at Mach 3.5 or around 2000mph

They'll test it on the ground and flying slowly first before going fast to make sure it's safe enough.

Reminds me of the ship from Gatchaman/G-Force/Battle of the Planets (just needs a new paint job and some minor modifications)

A rat done bit my sister Nell

With whitey on the moon

Her face and arms began to swell

And whitey's on the moon

I can't pay no doctor bills

But whitey's on the moon

Ten years from now I'll be payin' still

While whitey's on the moon

The man just upped my rent last night

Cause whitey's on the moon

No hot water, no toilets, no lights

But whitey's on the moon

I wonder why he's upping me?

Cause whitey's on the moon?

Well I was already giving him fifty a week

With whitey on the moon

Taxes taking my whole damn check

Junkies making me a nervous wreck

The price of food is going up

And as if all that shit wasn't enough:

A rat done bit my sister Nell

With whitey on the moon

Her face and arm began to swell

And whitey's on the moon

Was all that money I made last year

For whitey on the moon?

How come I ain't got no money here?

Hmm! Whitey's on the moon

Y'know I just 'bout had my fill

Of whitey on the moon

I think I'll send these doctor bills

Airmail special

To whitey on the moon