Check 6 Revisits: Birth Of The Blackbird, YF-12 Reveal And What May Be Next

On the 60th anniversary of an LBJ press conference, Aviation Week editors revisit the moment Lockheed’s YF-12 was revealed for the very first time, and discuss what similarities that unveiling might have with recent developments of today...

Check 6 Revisits delves into Aviation Week's more than 100-year archive. Subscribers can explore our archive here and read Aviation Week's coverage of the "A-11" here in the March 9, 1964, edition of the magazine: A-11 Proven In Reconnaissance Missions

Read the CIA memo on former Aviation Week editor Bob Hotz relating to the "A-11" here.

Listen to President Johnson's full speech here courtesy of the University of Virginia's Miller Center.

Don't miss a single episode of the award-winning Check 6. Subscribe in Apple Podcasts, Google Podcasts, Amazon, Audible and Spotify.

Discover all of Aviation Week Network's podcasts on our Apple Podcasts channel or aviationweek.com/podcasts.

Transcript

Christine Boynton:         Welcome to Check 6 Revisits, Aviation Week's new podcast series where our editors comb through more than a century of Aviation Week and Space Technology coverage. In this podcast, we'll explore pivotal industry moments and achievements of the past, while considering how they might relate to the events of today. I'm your host, Christine Boynton, Aviation Week Editor for Air Transport in the Americas. And today I'm joined by Aviation Week Defense Editor Steve Trimble and Aviation Week Senior Editor Guy Norris. You find us all together on February 29th, 2024, a date that marks the 60th anniversary of a press conference at the White House that revealed a member of Lockheed's iconic Mach 3 Blackbird family for the very first time.

President Lyndon B. Johnson:           The United States has successfully developed an advanced experimental jet aircraft, the A-11, which has been tested in sustained flight at more than 2000 miles an hour, and at altitudes in excess of 70,000 feet. The performance of the A-11 far exceeds that of any other aircraft in the world today. The development of this aircraft has been made possible by major advances in aircraft technology of great significance for both military and commercial applications. Several A-11 aircraft are now being flight tested at Edwards Air Force Base in California. The existence of this program is being disclosed today to permit the orderly exploitation of this advanced technology in our military and commercial program.

Christine Boynton:         That was President Lyndon B. Johnson on February 29th, 1964, and what he was doing here was a partial disclosure. The circumstances, a highly advanced aircraft developed by Lockheed in complete secrecy, may be eerily relevant today, but more on that later. So to kick us off, I'll note that LBJ said the aircraft was the A-11, even though it was the YF-12. That was not unintentional. So Steve, why the use of a different name? What else was being concealed? And what was so groundbreaking here?

Steve Trimble:              Yeah, there's just so much to unpack from that one little snippet of audio. So this is February of 1964, as you mentioned, it's an election year. It's a month after his Republican challenger, Barry Goldwater, is criticizing his administration for not sufficiently supporting the Mach 3 B-70 program, so that's in the mix and why possibly we're seeing the reveal of what he's calling the A-11 here. Obviously, as you mentioned, it's actually the YF-12 and I can get to that, but we also need to unpack several things.

                                  One is he says that they're in testing right now at Edwards Air Force Base, and when he said that, they weren't. They were at Area 51 at Groom Lake in Nevada, several hundred miles away from Edwards Air Force Base. In fact, the program knew that the announcement was coming out, but they didn't know when he was going to say it. So they first heard about it, but that he said that, when he said it, and the news broke about the program. So they had to scramble and launch the YF-12s, not A-11s, YF-12s from Area 51 to get them to Edwards Air Force Base, so that when the news crews and reporters from Los Angeles got to Palmdale and Edwards Air Force Base, they would see that there were these aircraft out there and the President wouldn't have been incorrect in his announcement. So that's one of the things.

                                  So, why is he calling it the A-11? That's another whole thing. There are so many different designations going on with the Blackbird series. Some of them are right, some of them are wrong. There's some myth about some other things about it. But the program starts out in August 1959, with a contract award by the CIA to Lockheed Skunk Works to develop something called the A-12, not the A-11. And so it starts there as a Mach 3 aircraft that can fly as high as 83 or 90,000 feet maybe, and it would carry a camera for the CIA to replace the U-2 with something that was high altitude and would hopefully be invisible to radar, although it never was.

                                  So the other thing the CIA did was they also found another aircraft that was called the M-21, another part of the Blackbird series that was just going to launch a Mach 3 drone, called the D-21, that would launch from the top of the aircraft. And that program didn't work out. There was a bad crash when they tried to do it and they had to shelve the program. And then the Air Force got involved. And so they had two variants of the Blackbird family, starting with the YF-12 and then of course with the SR-71, which we all know. Now, the YF-12 was actually an interceptor. It was a Mach 3 interceptor that was designed to launch and scramble and shoot down supersonic Soviet bombers before they could launch nuclear missiles at the United States. This was in an era where ICBMs were just beginning to become a threat, but still they felt like they needed to have some ability to intercept good old-fashioned bombers coming over the polar ice cap.

                                  So now, to answer your question why he's calling it the A-11, to try to unpack all these things, the A-11 was part of a design series that the Skunk Works started under what was called the Archangel program, which was the design study that led to the A-12 and there were 12 different designs. The last one of which was called the A-11, but it was just a paper design, it was never built. And I think, based on Kelly's notes and his log book about the A-12 program, it seemed like it was his favorite, because it was the one aircraft that was the most advanced, of all the designs, that was not compromised in any way for the radar stealth changes that they made to make it the A-12. And you could see a basic resemblance to what became the A-12, but it was very different. There was still kind of a double delta wing, like you see on the SR-71 or A-12, but it was a top wing, it wasn't a mid-wing. The engines weren't blended into the fuselage. They were slung under the engines. There was a single tail instead of those two canted tails. So that was the big difference.

                                  And it flew higher. It didn't fly any faster, because there was a constraint imposed by just the thermal issues on the engine, but it was a lot lighter, so it could go farther on the same amount of fuel. So that's why Kelly, I think, liked it the most. So when they announced it at the time, they still just had the CIA program that was called the A-12, and that was supposed to be covert. And so the President wants to announce it, but the program really doesn't want anybody to know about this A-12 program that's out there. And now, if they say that there is this program that's called the YF-12, this interceptor for the Air Force, well, I think they were worried about people getting that mixed up and getting that all jumbled up. So, they decided to call the YF-12 something else, for the purposes of the announcement, just to try to keep the A-12 safe. And they probably chose Kelly's favorite design of the Archangel series, which was the A-11 instead.

                                  So that's the history of all that. It's a weird history. And then there's still a lot of people, remember also six months later, that was when President Johnson also unveiled the SR-71 aircraft and there's this mythology built up that he announced it as the RS-71 instead of the SR-71. And it's actually not the case. It was intended to be called the RS-71, but Curtis LeMay didn't like that. And there's some really good research on this that just got published by Peter Merlin in his excellent book, "The Secret History of Area 51," where he breaks down how this myth got built up, that LBJ mixed up the name for the SR-71 and was supposed to be called the RS-71.

                                  And the issue with that was that there was another aircraft called the RS-70, which would've been a reconnaissance strike version of the Valkyrie, the B-70, the bomber. And so when the RS-71 or SR-71 came along, they applied the same designation. The problem is that that implied a strike mission for the SR-71. And Curtis LeMay didn't like that, because he didn't want anybody to get confused that his favorite aircraft, the B-70, was going to be the strike aircraft and not the SR-71. So, he turned it into SR-71, which Lyndon Johnson, when he announced, he announced it accurately the way Curtis LeMay wanted him to. So, there is a bit of mythology about that, but if you want to read more about that, read Peter Merlin's book, because it's really good.

Christine Boynton:         That's a lot to unpack. Thanks, Steve. No, that was great. Guy, I think you wanted to jump in here.

Guy Norris:                   Well, yeah, I was just going to say one of the things about that moment when, after Lyndon Johnson had made the announcement, and Steve mentioned they had to scramble Louis Schalk and Bill Park, who were the two test pilots really at the center of the program, flew two of the, as Steve said, two AF-12s to Edwards in a real hurry. In fact, they were in such a hurry that when they got there, they put them into the hangar and the engines were so hot, in fact, the airframes were so hot, because these things flew hot, they set off the sprinklers in the hangar. And so I think Kelly Johnson, of course, the famous designer, the creator of the Skunk Works and of these aircraft said, "We got a free wash out of the whole business." Anyway, just thought I'd throw that one in.

Christine Boynton:         And do any of these still exist? I think there's one, is there one left? Because I know one of them crashed and part of it was Frankensteined into a different aircraft. Steve, can you get into that at all?

Steve Trimble:              Yes. And you can see the aircraft at the National Museum of the U.S. Air Force in Dayton, Ohio. The last remaining YF-12. Yeah, there was one that was converted into an SR-71C for NASA and, yeah, one crashed.

Christine Boynton:         So I'm going to touch on another part of the press conference from LBJ, not part of the audio we played, but he does mention that one of the most important technical achievements was, quote, "the mastery of the metallurgy and fabrication of titanium metal." So Guy, this was one of three aircraft, I believe, to be powered by the Pratt and Whitney's J58. Can you talk us through some of the overall specs, including that engine, and really what was it capable of?

Guy Norris:                   Oh, boy. Yeah, like Steve said, there's a lot to unpack even from the programmatic perspective, but talking about the technology behind this beast... So, okay, let's start with the operating environment. This aircraft or the whole family of Blackbirds designed for the highest Mach number ever achieved, and to this day, well, we'll go into that more later on, but as far as we know, the highest speeds ever achieved by an airbreathing piloted aircraft that was not powered by rockets. So, airframe temperatures, now that's the thing you're talking about here, aerodynamic friction. Average surface temperatures were roughly between 460 and 620 Fahrenheit. So, if you imagine... But at peak could reach over a thousand degrees on certain parts of the airframe. That's over 565 degrees Celsius for those that are interested in that calculation.

                                  So, just like any materials, that precluded the use of aluminum, from an airframe structure perspective, you literally couldn't make it out of that. So in the end, they had to go to this dramatic use of titanium. Over 95% of the weight of it was made up of this relatively new material, certainly for airframes, that there was a bit of steel and a little bit of exotic, high temperature plastics. This is pre-composites of course. So, let's just think about titanium. They had to learn how to use, form and create, weld, put together all of these parts out of titanium. Nobody had ever done it before. So they had all sorts of issues. Part of the problem was the thermal expansion that you got. As the aircraft got hotter, it expanded, so how to build a structure without it literally popping its own rivet, sort of thing.

                                  So what Kelly's team came up with was this amazing idea of corrugating the inside of the structure. So, externally it was smooth to look, but inside it was this little corrugated set of a structural... And the idea here was that chordwise, anyway, the corrugations would absorb this heat, the heat flux, without warping. And in fact, Kelly Johnson joked that he was accused of trying to make a 1932 Ford Trimotor go Mach three. Of course, the other thing was the titanium. As I said, they couldn't really figure out how to make it, in the early days. 6,000 parts, at some point, 95% of them were rejected by quality, because they were cracking. They were just... So they had to figure out using an acid pickling system, they had to keep those parts away from, say, if you were using a drill, where the drill head had even been coated with cadmium, they found out that that would react with the titanium and cause some sort of corrosion in it. So all of these lessons.

                                  One of the great stories I love is they found out when they were spot welding, the spot welds that they did in the winter lasted indefinitely. And the ones that they did in the summer failed prematurely. And it turned out that Burbank City Water Department, the water treatment thing, would be heavily chlorinated in the summer to avoid algae growth in the water. And they realized that that was what was causing the problem. So they had to use distilled water from then on to wash all their parts. Steve, did you want to jump in?

Steve Trimble:              Well, and I just wanted to add, this is amazing hearing all these changes and this evolution, and they're learning as they go, but they start this project with 135 engineers, a 10th or a 20th or a thousandth of what you would see on similar projects of its era, like the B-70 at the time. And they literally went on a contract in August of 1959, and they were flying the aircraft, not with the J58, they had to substitute the J79, because it wasn't ready. They were flying in 1962 with that engine.

Guy Norris:                   J75, right? I think it was.

Steve Trimble:              It was J75. Thank you. Yes. J79 was the F-4 engine. Yes. But yes, they were able to substitute J75 engines and get it flying, just to get the aerodynamics figured out, and then the J58 came along later.

Guy Norris:                   So yeah. No thanks, Steve. You're right. That's a good reminder of what a miraculous thing this was, achieved with this core team that was minuscule compared with others. But let's look at the rest of some of the other elements here of what made up the Blackbird as it were. The other crucial thing about it was the leading edge sections, the vertical stabilizers, the chines, the very distinctive chines which we see on the aircraft today, they were mostly made of this phenylsilane material. And there was silicon asbestos, which of course in those days was still not known as being such a dreadful material, and fiberglass. And it was really strange, because although the A-12 prototypes, the M-21, which Steve mentioned, and the YF-12A used a lot of titanium in all of those parts, for the production vehicles, they decided that they needed, mainly for low observable, for stealth reasons, it was their attempt to try and make this beast stealthy. Of course, it was almost impossible, but that's what they tried.

                                  Another thing about that is really interesting is the Blackbird family is called the Blackbird, because of this decision to use high emissivity paint to radiate away the heat from the vehicle. It takes advantage of the black body radiation phenomena. And of course, they found out that you could actually, by painting it black, you could reduce surface temperatures by 54 degrees to cruising altitude, even though you added 60 pounds of extra weight by painting the whole thing black. And in fact, it was 60 years ago this year that they decided to paint the whole fleet black, and that's why they became Blackbirds.

                                  And the other one is the cockpit windows, it was just weird little things, you're like, "Okay, why is that a big deal?" You are dealing with cruise temperatures on the outside of 420 degrees Fahrenheit, but the boundary layer of the air is whizzing directly adjacent to the glass is up to 620 degrees Fahrenheit. Sorry, 630 degrees. So, you have to basically create a layer of two glass panels and a tiny air barrier between the two. There was actually a seven millimeter gap, so that's about 0.23 of an inch gap of air between the two adjacent panels. And each panel was made up of different layers, and apart from the outer window was just three eighths glass. But anyway, the point was that the heat, even with that protection, the inside temperature of that window, if you tried to touch it, was 80 degrees. Can you imagine that? So the pilot had to be protected. He was already in a spacesuit basically, but to make it even remotely comfortable, they had to pump in air at minus 40 degrees Fahrenheit just to chill that down, so that you ended up with a 60 degree Fahrenheit environment. Anyway, so that's the airframe.

                                  There's so many more things you could talk about, but to me, the most amazing achievement of the aircraft has got to be the propulsion system. Without an engine, you're not going anywhere. But this was an engine like nothing else that had ever been seen. As Steve mentioned, it was a difficult job to get this done. They began with the J75. That was good, managed to get them to Mach 2, but the big beast was the J58 and that was really what they wanted. Pratt and Whitney called it the JT10-11B, right, Steve? 11B-20, I think. The Air Force called it the J58. Anyway, but the inlets and exhaust design remains unparalleled in terms of air breathing, high speed engine performance to this day. The incredible single spool design, it's just a turbojet at the core of the system, had only nine compressor stages, which is, for what it was doing, was amazing. And just two turbine stages. A variable geometry inlet diffuser, complex air bleed bypass system, which could bypass air past the turbine and directly into the afterburner, which is basically turned the turbojet into this famous turbo ramjet.

                                  So let's just quickly talk about the inlet first. I love this stuff. Sorry. It's amazing. So it was an axisymmetric cone, basically, an axisymmetric inlet, with this spike that translated forward and aft. The further backward it retracted, the faster the Blackbird would fly, basically. So the mixed compression inlet works by slowing the air to subsonic speed before it reaches the compressor, because obviously nobody's even now built a supersonic engine like that. So the cone or the spike moved forward or aft depending on what part of the flight it was in to control the position of the shock wave, with the inlet Mach number. And the process was helped by these bypass doors, which opened or closed to maintain exactly where this shockwave position was. And the movement of these doors is automatically controlled by pressure sensors in the duct. But the pilots operated aft bypass doors as a function of the Mach speed and forward doors controlled the airflow at the turbine inlet.

                                  So, amazingly, and this is just what I think blows me away, is that even they managed to get this complicated system to work, this choreography of doors and cones and stuff, the Pratt & Whitney engineers realized that to get the maximum efficiency out of it, they had this issue, right in the center, this cone, you'd get this boundary layer that obviously formed over it. So they invented this porous center body bleed system, which basically took in even that little bit of boundary layer air and improved the overall inlet efficiency, as well as internal cowl shock traps and bleed control. It was amazing.

Christine Boynton:         That is amazing. No, I was just going to say, you mentioned, to this day, technology unsurpassed, and I want to come back to that at the end, but I'd also like to touch on some of the AW&ST coverage from back then, because digging into that was incredible and we'll absolutely post some of those PDFs in the show notes. But in the March 9th 1964 issue specifically, our then editor Bob Hotz covered this subject in detail and he, in that edition of the magazine, had an editorial where he commends Kelly Johnson and his crew at Skunk Works. He remarks on what the industry could accomplish with a specific mission and, quote, "a path free of bureaucratic red tape." And he ends the editorial with this, quote, "We paid our original tribute to Kelly Johnson for the A-11 performance on December 24th 1962, when we noted ‘Clarence Kelly Johnson of Lockheed Aircraft for his continued ingenuity in the Skunk Works.’ Until President Johnson's announcement, this was all we chose to publish on that project."

                                  So, that brings me to the next point I'd like to talk about here is this coverage was discussed in what is now a declassified CIA memo, which we'll also link in the show notes, but maybe you two can jump in on some of the colorful language in that memo. And really also how Hotz was, he was on top of this coverage, he knew a lot more about this aircraft than even the CIA had seen anyone else report this far.

Steve Trimble:              Right. Okay, so let's talk about Robert Hotz, himself, Bob Hotz, a legendary figure in Aviation Week lore. I think whatever reputation Aviation Week developed in that era was really the responsibility of Bob Hotz. He was an incredible editor. He started out as a B-25 pilot flying for Claire Chennault and the Flying Tigers in China during World War 2. He wrote a book about it during the war and somehow got it published and got it past the sensors back then. But then he went and joined Aviation Week and quickly became the editor and was really the driving force behind all the scoops that Aviation Week had, some more accurate than others back in the '50s, we have to admit, if you go back, we could talk about some of those things.

                                  But in the CIA memo that comes out, that has been declassified by the CIA, it's available on their website if you look for it and just search for H-O-T-Z, Hotz, in their CREST Archive of declassified documents, there's this memo to the security staff from James Cunningham, who was at that time the deputy guy in charge of this particular project, and saying that he ran into somebody else who had talked to Hotz. And there were some issues going on at the time about what Hotz knew about the program, but it reveals that Hotz had actually had approached the secretary of the Air Force, and maybe it was the chief of staff of the Air Force back in September of '63, so a few months before the "A-11", quote-unquote, was revealed, where Hotz came in and said… "Hey, I know about this program. I don't know what it's called, but I know you've got something. I know you're flying it and if you work with me and you give me privileged access, when you're about to announce it, I won't reveal it right now…"

                                  And he apparently felt like he got assurances from the secretary of the Air Force, or maybe it was chief of staff of the Air Force at the time, that that was going to happen. Well, of course, they... What Hotz probably did not know was that the Air Force wasn't really in charge of that program. It was the CIA and the CIA reports directly to the President. And the President announced this, even catching the program by surprise when he did. So Hotz did not get the privileged scoop when this happened. In fact, he wasn't even at the press conference that the White House called, because they didn't say what they were going to announce, and he had no idea that they were going to announce that. So we missed that scoop even though Hotz had it. So you could tell from the way that memo was written, was that they were a little concerned that they had annoyed the editor of Aviation Week by failing to adhere at least to what he had perceived to be some assurances that he was going to get the scoop on this before it was announced in the way it was.

                                  So that was the context of the memo, but there's some funny things about that memo, because it says that Kelly, or not Kelly, that Aviation Week's coverage got some things wrong, or at least that Hotz, not even in their coverage, but at least... It goes through some things that Hotz was telling the CIA, that he knew about this aircraft, that the CIA believed Hotz was wrong about. And Hotz hadn't reported these things, but he was trying to tell them… "Look, I'm not trying to reveal secret stuff that's going to get you guys in trouble with the Russians, if you try to fly these in operational missions. In fact, here are some things I know about this aircraft that I know are true based on my sources…" and the CIA was debunking those things, so that there's a chemical in the fuel that turns the exhaust orange. That was something that Hotz believed. And of course, anybody who's seen videos of the SR-71 fly knows that that never happened and that the CIA guy does talk about that.

Christine Boynton:         But there was a sketch, Guy, that we were talking about right before we jumped on this from our coverage. Maybe you can touch on that a little bit and why we could see why some of those things were interpreted that way.

Guy Norris:                   Yeah. Well, yeah. Now just to jump in on what Steve was saying, our own interpretation really from the Air Force or the images that were released, I presume by the CIA as well, Steve, I'm not sure, but maybe Lockheed, but-

Steve Trimble:              It was the Air Force.

Guy Norris:                   It was the Air Force. It was, okay, clearly show a perfectly rendition side view, for the time, but the top down view shows that they literally, that's all they were going on. They were fooled, I think, by that early pre-Blackbird paint scheme, because it looks... You can see why they gave this thing some weird outboard, relatively high aspect ratio wings when of course we know they never had that. The other weird thing is that Steve mentioned how Hotz was saying about this strange coloring, the orange stuff. Weirdly enough at the time, the only way to start... The thing about these aircraft is they used this low vapor pressure, high flashpoint JP-7 fuel, and it was so hard to ignite that you could drop a lighted match into a bucket of that stuff and it would just go pfft. It would go out. So to get it even started, you had to use this horrific stuff called pyrophoric triethylborane, I think it... TB was what it was called. And basically there was a tank in the aircraft that could, for up to 16 relights or starting the afterburner, either on the ground or in-flight, but the thing is when you press the button to do this, you've got a green flash. So there was some strange colors going on there, not orange, but green.

Steve Trimble:              And another thing that Hotz told the CIA that he knew was, because the CIA had come to him and said… You just reported in Aviation Week that the fins, the vertical stabilizers are canted 15 degrees, and we weren't going to tell anybody that. And now we're a little worried that the Russians know that… And Hotz said… Well, I know that that has nothing to do with radar stealth, and that's only being done for aerodynamic performance, so that's why we reported it, because we know that that's not an issue… And Cunningham, in his memo to the security guy at the CIA says, "This constitutes that Hotz knows neither his aerodynamics nor his radar," because in fact... The primary purpose of caning those fins like that was for reducing the radar cross-section, because you see that only in the A-12 and all the previous versions in the Archangel design series had a straight tail, because they weren't worried about the RCS. But in fact, there is some aerodynamic benefit and Guy, you could probably talk about that.

Guy Norris:                   Well, yeah. No, you're right. He may not have been spot on, but it would reduce the potential for roll/yaw coupling, for example. And of course the other thing is even-

Steve Trimble:              High AOA.

Guy Norris:                   Yeah, a high AOA, and of course... Yeah, you're right. The other thing, of course, if you have an engine unstart, which this thing was notoriously unfortunately susceptible to early on, you would get more ability to control that, of course, particularly at lower speeds when you've got two fins like that and especially with a cant. Should we just quickly mention about unstarts, because I think that's a big... Is that worth talking about?

Christine Boynton:         Yeah, jump into that. Yeah.

Guy Norris:                   Okay. So, one of the things is that, and this was a fearsome effect really that pilots, when it happened, they would refer to it as like being in a train wreck. So obviously, as we mentioned earlier, the key thing about these engines is to control where the shockwave is as it enters. The faster you go, the deeper that shockwave goes into the engine, and you had to maintain that by altering the position of that cone in the inlet. So if something happens to the position of that shockwave that you don't expect, say if you improperly control the inlet or there's a disturbance, the inlet itself would expel that shockwave out of the front again, and you'd get this fearsome surge-like event and it would violently yaw into the direction of the unstarted engine. And so the crews would be thrown around, they hit their heads against the side of this tiny cockpit. It was a pretty awful thing. So eventually, it wasn't until the '80s that they developed a digital automatic flight and inlet control system, which the computer basically looked after that choreography. But anyway, that was the fearsome unstart.

Christine Boynton:         Well, I think this brings us to the point we've teased now a couple of times where we've talked about this technology, some of which is unprecedented to this day, and about how some of the circumstances of this 60-year-old press conference being eerily relevant to today. So, I'm tossing it back over to you guys, Steve and Guy, what is it that you can tell us about what's happening now?

Steve Trimble:              So, it is February of 2024, 60 years after this announcement. We are in an election year. I'm not saying that that means that we're going to see a secret aircraft get announced or unveiled, because of that. I wish that were true, but the context is quite different this time. But there is a secret aircraft in development at Lockheed Martin Skunk Works in Palmdale. We know that, starting out, going way back till, I think it was, in 2021, maybe 2022, I think it was 2021, Safran in Canada announced that they had received a contract to develop the landing gear for a next generation, an advanced aircraft by Lockheed. And they didn't say what it was, and Lockheed wouldn't comment on what it was. And then disclosures started coming in Lockheed's financial filings, starting about a year and a half ago, saying that they've got this very advanced, very highly complex aerodynamic vehicle that's being developed as part of a program of record, and they're having some trouble with it. They'd already, on a fixed price basis, had lost about $270 million on the project and they were reserving another $900 million or so.

                                  And on top of that, we know that the employee count that the Skunk Works has disclosed has shot up since 2018, where it was around 2000, is now up at 5,500 at Skunk Works, which that is about the same as what they had at the peak of SR-71 production in 1964 and 1965 in Skunk Works way back then. So it does suggest something very large and a sustained program is in the works there. And in fact, we've got comments from the current director of the Skunk Works, John Clark, telling us back in September that yes, they do have some things in low rate production and he couldn't go any further, because of security restrictions.

                                  So, there's a lot that we know here, and there's a lot we don't know. There's a lot going on in the classified military aircraft development space. There's next generation air dominance. There's been prototypes developed for that, just one-off prototypes. So far, the contract has not been awarded. That's supposed to come later this year. Lockheed is in contention for that, but they wouldn't have commissioned a new landing gear quite yet until they get that contract. So we can probably rule out next generation air dominance. The timing of this, if you look at the similar programs and how they evolve and how many years it takes to go from contract to award, to nailing down the design, so that you can actually sign up your suppliers and get them in contract, there's a sequence that happens here. So it looks like this program was probably started around the same time as B-21, within a year or two, give or take, of the B-21. And we know the B 21 is part of a family of systems.

                                  So when the original Next-Generation Bomber Program was canceled by Defense Secretary Gates in 2010, because it was going to be too expensive as a standalone aircraft, the Air Force came back and proposed a long range strike bomber family of systems, which would include a bomber, it would include a penetrating ISR aircraft. It would include an airborne electronic attack aircraft as a family of aircraft. That's how they unveiled it publicly in 2010, I believe, very shortly after the cancellation of NGB. So, it is possible that one of these aircraft that comes out of that program going back 15 years ago is now sort of coming to fruition, except they may be having a little bit of trouble, because the last financial disclosure from Lockheed and their annual results last month suggested that there's some uncertainty that they have about some pre-contract costs that they've made, as I think that they're transitioning from development to production, that they're at risk, because the program could still get canceled. And so because of that, they warned shareholders that they might get stuck with some extra costs there, that they've invested to be ready in case a production contract actually comes forward. So that's all we know about this.

Christine Boynton:         Guy, did you want to quickly jump in there?

Guy Norris:                   Well, I need to say that, because 11 years ago, Lockheed basically came to us, to me and said, "Hey, we want to tell you about something we're developing or a plan. It's an operational hypersonic vehicle. There's the baseline for a scale demonstrator for what we're going to call the SR-72, which will be a replacement, of course, for the long retired Blackbird." And then it all went quiet. And then in 2017, I bumped into Rob Weiss, who was at the time the general manager for advanced development programs at Skunk Works and the executive vice president. And at that time he said… All I can tell you is the technology's mature and we, along with DARPA and the services, are working hard to get that capability into the hands of our warfighter as soon as possible… And he was saying, things are moving along pretty quickly, but it's important to stay quiet about what's going on.

                                  So, going back to what they told us in 2013 was, at the time, it was going to be a Mach 6 type vehicle. Lockheed Martin was working with Aerojet Rocketdyne on basically a combined cycle TBCC with a combined scramjet in it. And that was all... A lot of it was building on high speed development, they'd worked with for DARPA on the HT3X. So there was a lot of heritage and a lot of elements being pulled together for this. But Steve and I think that since then, maybe things didn't go as well as they hoped. This FTV, this idea to have a flight research vehicle, as they call it an FRV, which would've been a single engine unpiloted demonstrator, we think things didn't work out so well and maybe they had to scale back their ambition, which takes us neatly to, Steve, drum roll.

Steve Trimble:              Well, okay. So Pratt & Whitney, a couple of years ago, disclosed to us through this very sort of painful series of interviews, where we finally got some more information on it, this project they have called Metacomet, and Metacomet is a great name for a high speed propulsion system, by the way, but it actually comes from the name of the ridge that overlooks Pratt & Whitney's test facility in Connecticut, which is itself named from the Indian chief who led King Philip's War back in the 1600s against the New England colonists. But besides that, sorry, that's a very irrelevant history for this podcast, but I'll let Guy actually go into the technical details of Metacomet. But it's a nice bridge between what we were talking about before with A-12 and maybe where we're going with whatever this secret Lockheed aircraft is going. Even though, we don't have anything, I should be upfront, we don't have a connection. We don't know that Metacomet is the propulsion system for whatever Lockheed is doing, but we know GE is not doing something in this, because they just unveiled their high speed concept and it's very much at the very earliest stage of development. So that leaves Pratt & Whitney. If it's going to be air breathing and turbine-based, the engine's going to be coming from Pratt & Whitney in this space. But anyway, Guy, go ahead.

Guy Norris:                   Right. Yeah. No, that's a good intro actually. I think the point about this is that, and the reason why it's so wonderfully relevant to this podcast is the fact that the J58 is still an awesome technology and it's an architecture which could conceivably, 60 years later, be quite significantly updated. And we think that's really where Pratt has been looking at. For example, even in the later stages when NASA was the last to operate the Blackbird and it retired in the '90s, even then they were looking at potential ways of increasing turbine exhaust temperatures, looking at this compressor rotor speed, modifying the bleed system at the inlet, guide vane scheduling, increasing the afterburner flow. There was all the things you could tweak 60 years later, 30 years in that case. Material sciences improved. There's a lot of stuff. What you can also do, which takes the cycle even further, is beyond improvements to the compressor and the materials, you could actually look at adding some kind of supersonic combustion capability in the afterburner, which takes us to things like rotating detonation or other ways of augmenting the cycle.

                                  So, you could be talking about pushing a Mach 3.23 capable system up to Mach 4 plus, which is more towards the... It's not quite hypersonic, but it's getting awful close. So, I don't know. It's interesting. We just don't know. And I just said there's a quick thought before I forget it, because I'm forgetful, but I wanted to ask Steve about this. So, Lyndon Johnson made that statement, as you said, Christine, at the end of February 1964. Do you think it's... We're recording this on the 9th of February, which is exactly 60 years and six days after one of the A-12 prototypes was flown for the first time to its designed speed condition, Mach 3.2, by... What was his name? Eastham? A guy called... Sorry, I can't remember his first name. But anyway, it was the first time they'd actually reached their operational goal with the specification that was required. So I'm wondering, do you think that that was why three weeks later they said, "Okay, we know it's going to work now, because we finally reached the speed." Do you think there was any relevance to that?

Steve Trimble:              There's not a lot of information in the historical record about exactly why they decided to do it, but the timing and the intensity of the political attacks and pressure from Goldwater about the B-70, which was a huge issue at the time., it was not a small issue, it was a national type of discussion and debate over that program. And Congress, on both sides, Democrat and Republican, were very concerned about the ambivalence by not only the Kennedy administration, but even the Eisenhower administration, which originally sought to cancel the B-70. And so, knowing that it had finally worked in early February, I'm sure really helped build the case politically that they could announce this and not get egg on their face, that they were going to be announcing something that they would have to later on announce that; oops, it didn't actually work. So I'm sure that helped. But the timing, especially with Goldwater and the intensity of that campaign developing and Johnson wanting to say, "Hey, I'm not soft on defense, and you want your Mach 3 bomber, fine, but look, we just got a Mach 3 fighter interceptor and in six months, I'll show you a whole new Mach 3 strategic reconnaissance aircraft for the Air Force as well. Meanwhile, I've got still this secret CIA program I'm working on as well." So yeah, I think there was probably a confluence there. Yeah.

Guy Norris:                   Yeah. And just a quick shout out again for Pete Merlin's book, it was Jim Eastham. Just looking. Eastham, I've just checked in the book, it's his book.

Christine Boynton:         So exciting things to come. Any ideas about timing in terms of a year, 5 years, 10 years? Any thoughts on when we might be seeing that? Any confirmation of what we've been talking about?

Guy Norris:                   Yeah. Well, as you can say, based on what we were reporting in 2017 at that stage, before things were maybe not going so well, the possibility was that if this FRV vehicle worked, then that would step up to the full scale vehicle, which at the time we thought would enter flight test maybe later this decade. So, if that's true, we could be talking about something that's at subscale right now and the full scale vehicle, if you want to go up to Area 51 and keep a look-out, maybe four or five years time, you might be seeing something. Who knows?

Christine Boynton:         Yeah. Well, I know we could keep talking about this for another hour. And that's what I'm going to love a lot about this podcast series is it's just going to be epic geeking out over various topics. So thank you both for helping us launch this podcast. Really excited for the next episode as well, which we'll talk about at a later time. But that's a wrap for today. A special thanks to our podcast producer in London, Guy Ferneyhough, and to Steve Trimble and Guy Norris for helping us launch this series. A special thanks also to the Miller Center for the LBJ audio.

                                  Now, for a full link to that recording that we played at the beginning of this episode, check the show notes at aviationweek.com, Apple Podcasts, Spotify, or wherever it is you get podcasts. We'll also pull from the AW&ST archive and post some of those articles we were mentioning as well. And if you'd like to delve into our archive for yourself, Aviation Week subscribers can head to archive.aviationweek.com to dive in. If you enjoyed the episode and want to help support the work we do, please head to Apple Podcasts and leave us a star rating or write a review. Thanks very much for listening, and have a great week.