What is the SR-72, 7 questions for Lockheed Martin Corporation?

What is the SR-72? – Today we will talk about the latest U.S. project of the sixth-generation reconnaissance strike system. In early June 2017, the U.S. aircraft corporation Lockheed Martin officially announced that conceptual studies of the possible weapon design of the attack modification of the advanced multipurpose strategic unmanned aerial vehicle SR-72 have been completed.

What is the SR-7, What is the goal?

MilitaryEzyInfo.com – Serial aircraft SR-71A “Blackbird” (Blackbird) was a breakthrough air defense in flight at an altitude of 28 km / h (M = 2,8), which briefly could increase to 3460 km / h (M = 3,2). The temperature of the skin at the points of the most intense braking flow (fuselage nose and air intake cones, leading edges of the wing and tail, nozzle ejector shells of engines) reached +427 ° C against the usual +150 … 250 ° C. This gave a chance to scout an object covered SAM S-75 or interceptors MiG-25P due to the fact that they needed a considerable (2.5 … 7.5 minutes) time to go into firing position or to take off and go to the launch site. Even with this capability, the SR-71A could only accomplish its mission if the target was located a short distance from the border and had only one air defense line to protect it.

Completion of creation in the USSR of a unified radar and information field in the air defense system of the country, as well as acceptance for service of SAM S-200 and interceptor MiG-31, made the SR-71A obsolete, and it was removed from service. However, work began immediately to create a replacement for it.

Completion of a unified radar and information field in the USSR air defense system, as well as the adoption of the S-200 SAM and the MiG-31 interceptor, made the SR-71A obsolete and it was taken out of service. However, work began immediately to create a replacement for it.

The SR-72 aircraft should reach speeds of up to 6,400 km/h in this mode at altitudes above 30 km, and according to some reports, even 70 km. Its range will be at least 6,000 km, and some estimates give a double value, which means the possibility of intercontinental operations. Unlike its predecessor, it will be unmanned: its customers and creators believe that this is the only way to realize the coveted American concept of “war without human casualties” – for America, of course.

That is the task at hand and it is not much different from what the designers of the SR-72 did.

Who is the “father”?

What is the SR-72? | In a number of statements by Lockheed Martin executives, the new SR-72 was referred to as the “son of the Blackbird”. However, it was immediately followed by caveats that this project is based on completely different principles, and they are not even successor to those used on the SR-71. The only thing they have in common is the way of breaking through the air defense in flight at a very high altitude and speed. According to the idea of the founders, it should reduce to the maximum the time that the calculation of the antiaircraft missile complex or the pilot of the interceptor would have to shoot down such a plane. The idea is old, but so far they have not come up with anything better.

So what is the basis of the XR-72 program?

America itself has vast experience in creating supersonic aerodynamic aircraft, the most famous of which is the hypersonic North American X-15 rocket plane. It made its first launch from the carrier NB-52 on September 17, 1959, tested for nearly 20 years, reached an altitude of 108 kilometers, and reached a speed of 6206 kilometers per hour. However, the flight of the X-15 in this mode lasted only a few tens of seconds, it was purely experimental and could not be used as a platform for reconnaissance equipment and even less – arms.

The SR-71A aircraft had two J58-P-4 single-circuit turbojet engines. Some sources indicate that they had a combined cycle, or that the power plant of the SR-71A was a combination of turbojet and ramjet engines, but this is not true.

Indeed, the gas dynamic characteristics of the J58-P-4 change significantly with a change in M number from 0 to 2.8…3.2 (which in particular gave a significant reduction in fuel consumption at maximum speeds), but its cycle remains characteristic of a ramjet – that is, the compressor, combustion chambers, and turbine continue to perform their functions in the usual way. However, their share in creating thrust is reduced to 20% of its total balance, and the rest gives the flow around the entire engine through a special circular channel in its nacelle (such nacelles on the SR-71A, recall, two).

Classic ramjet and differs from all other ramjet engines in that it has no compressor or turbine, and the fuel is burned in a stream compressed only by the air intake. In the nacelle channel of the SR-71A, like in the ramjet, there is no additional compressor or turbine for its drive, but there is also no fuel combustion – it occurs exclusively in the combustion chambers of the turbine installed inside it and this distinguishes it from, say, the French Griffon aircraft. In fact, the SR-71 nacelle is just a very large and long ejector, which draws more mass of outside air through the main frontal inlet with a central cone and the rear side one, and gives this flow additional energy through interaction with the jet of a conventional turbojet.

The SR-71 ejector is unique in its wide range of Mach numbers at which it is not “locked-in” by the flow. This range is indeed very large, but not infinite. Studies have shown that it is impossible to further increase the speed of the SR-71 by increasing the thrust of the propulsion system for this reason, too, and because of problems with the strength of the heated to a huge temperature airframe structure, and because of critical changes in the stability and controllability characteristics of the aircraft. In addition, already at speeds above 3000 km/h, there is a strong ionization of the air flowing around the aircraft and its cladding, which only increases with approaching the upper boundary of the stratosphere, where the physical properties of the air begin to change.

All of this raised a new barrier before the designers, who had already overcome the sound and thermal barriers – the hypersonic barrier. It turned out to be so technically complex that a number of very expensive projects had to be simply closed, although huge sums of money had already been spent on them. “America could not create an airplane that would fly in the atmosphere a little slower and a little lower than, say, the Space Shuttle, but much longer than it, and somewhere in the early 1990s it was announced that it was fundamentally changing the very concept of Air Force development. Now the main trends are stealth technology, high-precision weapons used according to the “shoot and forget” principle, as well as the integration of ground and air control points of the air group with airborne targeting and navigation systems of all aircraft in it on a global scale.

In terms of strategic aviation, the brightest example of the new strategy was the Northrop-Grumman B-2 Spirit, a low-visibility monster at a cost of $2.1 billion apiece.

Leaked information about the Aurora program of advanced hypersonic strategic reconnaissance and strike complex was the “first bell” that informed the world that this program had been closed. But did such a program really exist, or was this “leak” just a hoax, a cover for continuing work on exactly the same, but really existing under a different, no one “made public” code, which continued to quietly devour the “black items” of the Pentagon budget? Today, hardly anyone can answer this question responsibly. Those who talk do not know anything and those who know are silent.

At the same “dim time” not only for the Russian military-industrial complex but also for its American adversary, in the early 1990s, there were reports that America bought in Russia the results of experimental super high-speed aircraft tests that began back in the USSR. In particular, Piotr Butowski, a popular Polish expert at the time, who in the years of “perestroika and glasnost” actively visited many Russian defense enterprises and interviewed their leadership, wrote that among other things the reports on the flights of hypersonic “drones” D-2B and GELA were purchased.

In June 2001, the U.S. began testing the X-41 Hyper-X hypersonic drone. Its first flight ended in a crash, but on November 16, 2004, the X-41 reached a speed of 11950 km/h (3.3 km/s), which corresponded to M=9.6. The X-41 clearly had GELA features in its appearance, but it was smaller.

The Hyper-X program was managed directly by NASA on the budget, but the Office itself does not design aircraft, much less build them. The X-43 was a Boeing product.

The next vehicle, the X-51 Wavraider, was made in the same spirit. This was also a joint product of NASA and Boeing. It showed more modest data (maximum – 6200 km/h or M=5.1), but the share of the GVRD of the apparatus itself, but not of its upper stage in these figures was already greater, and the “booster” itself was significantly smaller than that of the Hyper-X.

NASA is a non-profit organization, and all its results are publicly available. Well, almost everything. So, although Boeing made the X-43 and X-51, Lockheed Martin can use the experience from their tests. However, according to the official statement of the corporation, its SR-72 – a completely independent project, relying only on its own achievements. The corporation’s official website literally says the following:

“The SR-72 is not Skunk Works’ first hypersonic aircraft.

“Skunk Works” is the now official joking name for Lockheed’s most classified design department, where all of the SR-72’s predecessors were created. As they say, it was invented by the first employees of this department in the 1950s, after reading comic books about how some scoundrels made magic moonshine in the jungle, adding to the brew live skunks for flavor. And really, a normal person would probably need some kind of “neurostimulator” to get to the bottom of the machines they were making. The peak of their creativity was the Archangel-12, the SR-71, which was unlike any other aircraft.

However, the direct basis for the project SR-72 the same site of Lockheed Martin Corporation calls not it, and a series of experimental hypersonic unmanned vehicles Hypersonic Technology Vehicle – HTV. They were created under the direction of DARPA (Defense Advanced Research Projects Agency). In contrast to NASA, the Defense Advanced Research Projects Agency is not a charitable organization, it works for a particular customer for a particular taxpayer’s money, and its costs are not usually publicized. And it was Lockheed Martin Corporation that implemented the HTV project under the strict supervision of DARPA.

And lastly, the same Lockheed Martin website directly states that the SR-72 project is headed by this corporation, but it also involves other private U.S. firms as subcontractors.

What is an HTV?

Essentially, a Hypersonic Technology Vehicle is a ballistic missile warhead stuffed with control and recording equipment instead of a nuclear charge. But of course, this is a very simplified statement. So simplistic, in fact, that it is almost wrong.

First, unlike the “primitive” conical or near-conical shape of the “ballistic city-killers”, the HTV is flattened. This improves its aerodynamic quality (the ratio of lift to the total resistance of the airflow around the body). The change in its shape at different stages of the Falcon project is shown in this figure distributed by the DARPA Press Center.

So step by step the designers increased the aerodynamic quality of the vehicle from 2.5 to 5.0 units, giving it such properties, which an ordinary ballistic missile warhead does not have – it can perform deliberate maneuvers, including upward, without being destroyed by enormous dynamic and thermal loads. And they are gigantic – after all the Mach number is no longer 5…6 as in hypersonic aircraft, but 15…17!

So, HTV is not a warhead analog after all? Yes and no, but that is not what we are interested in how – it is better to see how the evolution of the Falcon / HTV project resulted in the same “knife” in the nose of the vehicle instead of the usual needle-shaped cone. It may not yet be the same as the GELA, X-43, or X-51, but, as they say, “not yet!”

I wonder, what did the Soviet-made “planning ballistic block” look like that Russia is now threatening to use to penetrate the US missile defense “if anything”? I wouldn’t be surprised if it looked exactly like the HTV pictures above.

That remains unanswered for now

The most intriguing question is what will the new miracle plane look like? On the website of the corporation since 2015, there are such pictures (we took one of them from other sources just for the sake of better resolution).

It would seem that everything is clear: the businessman showed the goods with his face, and let it, the goods, does not exist yet, but the futures transactions is a good worldwide practice for a long time and there is nothing to doubt that the product will be something different.

However, looking at the first pictures of V generation ATF fighter, published in the early eighties, and at the “live” Lockheed Martin F-22A Raptor, you begin to doubt this. These doubts are exacerbated by the cover of the children’s magazine “Popular Science” with exactly the same plane, which is shown here, on the Lockheed – Martin Corporation website, as if in mockery.

What kind of engine do you have?

Oddly enough, this is the only question to which Lockheed Martin’s answer seems to be uncontroversial. This is how the SR-72 propulsion system is presented on the corporation’s website.

Why is this part of the information provided by the firm to be believed? Because it doesn’t contradict the physics or the direction that NASA and DARPA have been taking for the last 15 years.

So are we clear?

Not at all. It remains to be done. I don’t mean lab samples – we already have them! – but a full-scale aircraft with working engines. After all, there is always the possibility of failure, and then you have to start from scratch.

How to watch and how to shoot?

The Lockheed – Martin website says that tests of the HTV-2 experimental vehicle collected data on three aspects of hypersonic flight:

– aerodynamics;
– aerothermal effects;
– control and navigation.

It is the latter that is of most interest to me. After all, they have flown at such speeds before, but on uncomplicated trajectories and under full control of external means of observation. They were observing, but if anything, they could not help.

As we have already said, the surface of a vehicle flying at hypersonic speed in the upper layers of the atmosphere is highly ionized. Moreover, since such a spacecraft will be visible on the radar for many thousands of kilometers, there is an idea to “hide” its exact location in a huge artificial plasma cloud, which will be created by a special onboard generator. Then the radar will not see a marker point, but a many kilometers long shapeless zone of space, and the seeker head of the interceptor missile or SAM will not be able to find its target in it.

Of course, this is very good, but there is a question: will the radio and optical systems of such aircraft be able to “penetrate” this “cloud”? After all, it is a powerful source of interference in the radio range, and what will be visible to the eye or a camera “out of the window” can be easily seen on numerous video frames taken through the portholes of landing descent vehicles of ordinary spacecraft or shuttles. Nothing can be seen there but frantic fire and neither infrared, nor laser, nor any other optical imagery existing nowadays will help to discern what is down there on the surface of the Earth.

So, is it all so hopeless?

Not really. Radio and television communication with astronauts on takeoff and landing is still working, telemetry arrives, but with distortions and losses of some information. This problem has long been under attack, but it has not yet been solved. But the structure of “digital packages” navigation, reconnaissance, and targeting data, which will have to use SR-72, much more complicated than those that the spacecraft usually exchanges with the Mission Control Center and communication stations at launch or landing.

But I guess there is hope since the Pentagon decided to splurge? Or is it just that “the guys are in on it, too”?

In any case, for this fundamentally new reconnaissance strike aircraft they will have to make fundamentally new systems of targeting, reconnaissance, navigation, and communication – the ones that we have today will not provide a solution to the tasks at hand. Fully autonomous navigation, a kind of “thing-in-itself” on board the aircraft and having no communication with the outside world is suitable for space or ballistic missile, but not for such an aircraft. There is nothing to talk about reconnaissance and targeting – here the problem is visible, as they say, with the naked eye and this requires a system open “both outside and inside”.

Whether such an “open system” will work for the developers is also an open question.

It is even more difficult to shoot from the board of such a vehicle. I mean the process of actually separating the munition from the carrier and its proper exit to its intended trajectory of flight to the target.

When the flights of the first U.S. space shuttle Columbia began, there was a crazy idea to launch it into the atmosphere up to 50-70 km above Moscow with the opening of the payload and return to orbit. At that time the most fashionable topic was so-called “Star Wars”, i.e. transferring military operations into outer space, where America had a decisive advantage over the USSR. At least that was what the subordinates of U.S. President Ronald Reagan, who was suffering from Alzheimer’s disease, believed.

I do not know if such a dynamic descent with re-entry into the atmosphere and re-entry into space on the Shuttle was carried out, but the hatch was definitely not open in such a mode. Otherwise, the fleet of these marvelous spacecraft would have dwindled even before the first Challenger disaster.

The latest statement from the Lockheed-Martin Press Center says that the SR-72 will still get strike capability. The picture above shows how much space is taken up by the propulsion system on it, with most of that volume being its “empty” channels. And also the picture does not show the tanks – although they say that the proposed way to create hypersonic thrust is very economical, it is scary to imagine how much fuel the SR-72 will need to take off at, say, the Maynott airbase in North Dakota, “unload” over … (you know where) and land, for example, at Kadena airfield in Okinawa. All other options are not worth the expense involved.

That is why nobody is surprised by the information that the armament of the plane will be small air-to-ground hypersonic missiles. They are developed under the High-Speed Strike Weapon program, but other ones are mentioned as well.

A resurgence of the HAW – Hypersonic Aerodynamic Weapon – project banned under START-2 is not ruled out. A small solid-propellant missile hit the target with a beam of rods made of a superstrong alloy and accelerated to hypersonic. Concrete in the thickness of bunker protection was to boil from contact with them.

So, this missile will probably be hypersonic. But what kind of warhead would it have – it is possible that it would be nuclear. After all, you can not place a lot of them on the SR-72, and a little – there is no point. Only a “nuclear sledgehammer” can justify the expected costs. And at the same time solve the difficulties with targeting in light of the aforementioned problems with navigation.

What’s the price?

But let’s imagine that Lockheed-Martin succeeded and in 2030 the first SR-72 planes came into service of the U.S. Air Force Global Strike Command – how would the United States Air Force look then?

Allow ourselves to fantasize and assume that exactly such thoughts go to the bright head of the President of Lockheed-Martin Corporation right now.

So, let’s dream for him about what will be no later than in a decade and a half.

Four hundred McDonnell Douglas F-15C/E heavy tactical fighters are all sold out among oil sheikhs, African czars, and Poles and replaced by the modern Lockheed-Martin F-22 Raptor, which will not be 185 like now, but the same 400, maybe even 500.

The light tactical fighters Lockheed-Martin F-16 “Fighting Falcon” (yes, yes, already Lockheed-Martin, not General Dynamics!) still remain and they still are a lot, but their days are numbered and the Pentagon corridors are crowded with buyers for them. And those that will not be sold will be converted into QF-16 target planes – unfortunately, time is a merciless thing!

And the rusty remnants of the once large fleet of A-10 Thunderbolt II attack planes (who remembers the long bankrupt Fairchild firm that built them?) will be sold off between movie studios like Twentieth Century Fox and Paramount, where they will play “future planes” – they, like most F-16s, will be written off and replaced. With what? Yes with the new F-35 Lightning II. Whose? By Lockheed-Martin, of course!

And finally, the obsolete and useless “strategic junk”, intercontinental bombers Boeing B-52H Stratofortress, Rockwell B-1B Lancer, and Northrop Grumman B-2A Spirit, of different degree of decrepitude, are already written off and sent to the main cemetery of the American aviation history, Davis Montana base.

And in their place will come the newest B-3A (also their own, of course, if Lockheed-Martin with its partners from Boeing will sue Northrop-Grumman – our website also wrote about the lawsuit between them.

It is true that with the B-3, the Pentagon slightly “framed” their suppliers, rewriting the specification so that from a super-expensive supersonic aircraft generation “six plus” it became a scaled-down and cheapened version of the B-2 generation “five minutes”. But the SR-72, which does not replace, but complements the B-3, while remains conceived as “cool and tricked out” as possible. On them, you can earn a very big, giant, well, just unreal money! After all, only on the conceptual part of the project, when it is necessary to determine only in general terms, what should be done, and to show the congressmen and their constituents some irresponsible image, more than 800 million dollars are already allocated. The experimental hypersonic demonstration plane in the size of the F-22 will cost a billion, and one production SR-72A, which will be 2.5-3 times larger and 8-10 times heavier than such a “prototype”, will cost the American taxpayers at least 8 billion. The president of Lockheed-Martin still remembers a time when you could buy two Nimitz-class nuclear-powered aircraft carriers for the price of one such plane – that’s business!

Yes, yes, of course, such prices were in the last century and the dollar has lost a lot of weight since then, but still agree – the sum is impressive. Be that as it may, if the SR-72 will be adopted in the armed forces, it will stand at the top of a giant pyramid of the U.S. Air Force and it will be about him again said the magic words: the most expensive aircraft in history!

Although of course, we will not name the price of the question now, we can imagine the scale. But what will those who may be attacked by this aircraft do and what will it “cost” them?

Today, any action to eliminate or offset the threat posed by the yet-to-be-born SR-72 may take only three countries – India, China, and Russia. The others can simply not worry, the old weapons are enough for them. Their response can be (and almost certainly will be) both symmetrical and asymmetrical. But the question of what exactly can be done will be asked, of course, not to the creators of the SR-72, but to those against whom it is aimed. We will certainly talk about this in the pages of our web site, but next time.