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Department of Defense Press Briefing on Hypersonics

March 2, 2020
Dr. Mark Lewis, Director of Defense Research and Engineering for Modernization; Mr. Mike White, Assistant Director for Hypersonics

STAFF: So, good afternoon, everyone. Thank you for coming. Today, we're joined by Dr. Mark Lewis, director of Defense Research and Engineering for Modernization, and Mr. Mike White, assistant director for hypersonics. Both Dr. Lewis and Mr. White work under the Office of the Under Secretary of Defense for Research and Engineering. 

Today's briefing is going to be a little different than most of the other press briefings that we hold, given the considerable interest in the Defense Department's development of hypersonics technology. We will have brief opening statements, and then open the floor for your questions -- and that's the main reason that we're here. 

That said, please understand that there are some elements of the program that we're not going to be able to talk about because of the sensitivity of -- of the subject. So we have 30 minutes for discussion. I'll ask that each of you please raise your hand to be recognized and please state your name and your affiliation. 

So, that said, I'll turn things over to Dr. Lewis and Mr. White. 

DR. MARK LEWIS: This -- ah. Well, first of all, thanks everyone for coming. It's great to see so many familiar faces in the audience. 

So for those of you who don't know me, and as the colonel just said, I'm Mark Lewis. I'm the director of defense research and engineering, overseeing the modernization portfolio for the department. 

We have 11 modernization technology priorities in that portfolio including hypersonics. And essentially, those priorities come directly out of the -- the priorities that were outlined in the National Defense Strategy from 2018. 

A little bit of background on myself. So I've come to this position immediately from the Institute for Defense Analyses, spent most of my career as a faculty member at the University of Maryland in the Department of Aerospace Engineering. And spent four years in the mid-2000s as the chief scientist of the U.S. Air Force. And I've been in place, I guess, since early November so I'm no longer the new guy. 

So with me -- and the guy who's going to answer all the hard questions -- is my assistant director for hypersonics, Mike White. And Mike has also been in the hypersonics field for -- can I say decades? 


DR. LEWIS: Decades and decades. We both started as child prodigies. And he's overseeing our activities, including the team that is coordinating our hypersonic efforts across the department. 

I will tell you that -- that fielding hypersonic weapons, although it's one of a number of priorities, it certainly is one of our very top priorities. And -- and in doing -- in assembling that priority, we look at options across the board. Hypersonics isn't just a single thing, it's a capability that includes land, air, sea options. And our ultimate goal is, simply, we want to dominate future battlefields. 

So our job in R&E [Research and Engineering] is really to help to foster a unity of effort across the department, working with the services, working with the agencies. And we have a focus on both offensive and defensive systems, but we're also looking at such issues as the industrial base and industrial base requirements to ultimately produce hypersonic capabilities at scale. 

I'll tell you, since coming to this -- this position, I don't know of any part of the portfolio that – the modernization portfolio -- where I see such close coordination between the services and the agencies. It really is a good news story. Interactions between Air Force, Army, and Navy should make the American taxpayer very proud. 

So with that, let me turn the -- the floor over to -- to Mr. White.

MR. WHITE: Thank you, Dr. Lewis. 

As Mark said, I'm Mike White. I'm the assistant director for hypersonics. So in that role, I have the responsibility for integrating and coordinating across the department on all of our hypersonic activities, both our offensive systems and then our defense against adversary hypersonic systems. 

I came to this job in November, essentially, end of October of 2018, retired from the Applied Physics Laboratory after 37 years there, most recently as the sector head for Air and Missile Defense, leading a team -- very large team of over a thousand people, working in air and missile defense for the Navy and Missile Defense Agency primarily. 

But that was just the -- the last stop in a career that spent several decades working hypersonic systems, and then strike systems, and then defensive systems. So coming to this role, really, it was the opportunity to pull 37 years of experience together to look at the offensive and defensive capabilities necessary to field transformational capabilities associated with hypersonic systems. 

I say that, that way, very purposefully. We really are talking about transformative capabilities, and developing those capabilities by leveraging hypersonic systems. It's not about hypersonics for the sake of hypersonics. 

Our previous endeavors in hypersonics have been mostly in the research and development and S&T [Science and Technology] realm, and we've kind of failed in the past to make that transition from S&T and R&D [Research and Development] over to application to weapons systems and -- and that's really what has changed now. 

We have accelerated our transition of capability, based on hypersonic systems, with the most recent budget cycle in F.Y. [fiscal year] '20, that we're starting right now. And -- and the idea, really, is how do we make sure that we're going to deliver to the warfighter on -- as – as expeditiously as possible, transformative capabilities that maintain our battlefield dominance in future engagements. 

So with that, I'll just say that we are happy to be here as a team, helping to lead the integrated activity across the services and OSD [Office of the Secretary of Defense] to field those capabilities. 

STAFF: So, we’ll start first with, Tony? 

Q: Hi. Tony Capaccio with Bloomberg News. Two quick questions, what system will be the first to be test-flown this year? And then I had a second question. 

MR. WHITE: We will fly the Navy -- or the Navy, Army-derived capability from the Conventional Prompt Strike program, that was the OSD-led effort for (inaudible). 

Q: Window wise?

MR. WHITE: The dates are classified, but, it's later this year. 

Q: Yes, second question. You have said repeatedly that you don't -- you want your work force to not be afraid to fail. At what point does a failure though become a waste of taxpayer dollars. You've mentioned that the taxpayer will be happy with the coordination between the services, but at what point does it become a billion dollar fiasco. 

DR. LEWIS: So, let me take that one. You know, I put failures into two categories, there are noble failures and there are dumb failures. Noble failures. Noble failures are when something didn't work the way you thought it would work, but it wasn't for lack of effort, and, in fact, in that process, you learned from that. That's a noble failure. In fact, sometimes the noble failures are most informative things you can do in flight test, because you learn from that, and you move forward.

There are the dumb failures where, you know, fins fall off and squibs don't do what they're supposed to do, and those are the one's that we -- we definitely try to avoid. And that's why I say, our in-flight test, our teams need to be able to fail, but fail for the right reasons. 

So, that's not a license to make bad decisions, it's not a license to take unnecessary risks. It means, formulate our plans correctly, formulate our plans well, but maintain that experimental, experimentalist view in order to learn the most that we can from these activities. 

MR. WHITE: I think that that's a really important point. I'll just add to it real quickly, in that we are still in the discovery and invention phase and the design phase in all of our systems right now. 

And so, you learn through experimentation. So, they upcoming flight test is called, Flight Experiment Two. We're still -- we're still doing flight experiments prior to transitioning to weapon system prototype testing. 

And so, we will be -- there will be discovery and like Dr. Lewis said, we don't want that discovery to be associated with, oh, we should have had better systems engineering rigor. We want it to be discovery associated with the hard problem of flying hypersonic systems. 

STAFF: All right, so let's stay on the front row first and then we'll go back. 

Q: OK, so John Tirpak, "Air Force Magazine." Dr. Roper spoke to us in -- on Friday in Orlando about Hacksaw [HCSW - Hypersonic Conventional Strike Weapon] and Arrow [ARRW - Air-Launched Rapid Response Weapon] and why the Air Force went with Arrow. And he was talking about that gives it -- the Air Force an opportunity to start developing the industrial base and choose suppliers and what not. I was wondering, isn't that a little premature, number one, and number two, if Arrow is supposed to be based on the TBG [Terminal Boost Glide], and they're operating in parallel, how does Arrow learn from TBG if it's actually a little ahead? 

DR. LEWIS: Want to take that?

MR. WHITE: Sure. So, Dr. Roper's comments on Friday really described the difficult decision that the Air Force had to make in stopping Hacksaw at the CDR [Critical Design Review], which is later this month. And that decision really was budget driven. 

Ideally, you know, the Air Force made a very aggressive lean forward decision a couple of years ago to not only put one hypersonic program in place, transitioning from the S&T world to a weapon prototype world, but to realize that that involved risks and they put a second one in place in case -- in case those risks were realized. 

Both systems have been matured and we're in the process of taking those systems up to CDR-level of development and the Air Force made a difficult budget decision in '21 that basically said, hey, the envision-desired system is associated with TBG and Arrow, we need to place our bet now and then we'll wrap Hacksaw up, put it on a shelf and be able to pull it off if we need it, but we want to focus our energies on Arrow to make sure that that's successful. 

DR. LEWIS: I should point out, it was decision that we had already fully -- fully supported. We think that Air Force made the right technical decision as well. I mean, given the -- given the constraints that they had, picking between their systems, they made the right technical decision. 

Now having said that, you raise a great question, which is that, you know, Arrow is being -- is -- is leveraging efforts under the DARPA [Defense Advanced Research Projects Agency] TBG program. And we've got really good connectivity now between DARPA and the Air Force, to make sure that they're working hand in glove. That DARPA understands the importance of what they're doing and how it factors into the Air Force activities. And that's something that we and R&E are -- are really quite focused on.

Q: So, if could quickly follow up on --


Q: -- he also mentioned the idea having dual producers and competitive procurement later on. Are you talking about taking one design and giving it to two companies to -- to produce or are you thinking about a slightly different variation of the idea?

DR. LEWIS: So, we're not really talking about one design and multiple producers yet. We're talking about variations in idea, and, part I'll come back to. We're doing flight experiments, and we want to have a range of options available for the various systems we might pursue. 

MR. WHITE: We're putting together an acquisition strategy. So, we've transitioned from R&D to weapon prototype. The next transition is from weapon prototype to acquisition of actual weapons and that's where the acquisition strategy will come into play that whether we have competitors and the like. 

STAFF: So, let's got -- we'll go to Patrick and then Theresa and then --

Q: Hi, Steve Trimble with Aviation Week. On the air breathing side --

DR. LEWIS: Right. 

Q: -- can you lay out when you think there could be an air breathing version of what we're doing with Arrow and CPS [Conventional Prompt Strike] and LRHW [Long Range Hypersonic Weapon], and what would that look like? Is it strictly air-launched? I mean, you could take that and make ship-launched or surface-launched. Is there any interest in doing that or would it be completely different programs?

MR. WHITE: Yes, so we're -- we're looking at a broad set of air-breathing options. I really wouldn't characterize it as an extension of TBG or Arrow, those are boost-glide systems. It's a completely different configuration. 

But, we are looking at air-breathing hypersonic cruise missile configurations, initially primarily focused on the DARPA HAWC [Hypersonic Air-breathing Weapon Concept] program and the transition of that to an air-launched cruise missile configuration, with the Air Force. But, we're also looking at some other configurations that have a broader range of capabilities. 

One of the side benefits of the Air Force stepping away from Hacksaw and putting a bow on it at CDR, is they can now focus on the air-breathing transition as a -- as a second potential hypersonic transition opportunity. 

Q: Can you define, what would be the mission for the cruise missile versus the boost glide system?

MR. WHITE: The mission for the cruise missile has to do with -- or the value proposition, let me put it in that term, the fact that the cruise missile is smaller, so it -- it's more affordable, and it fits on a wider range of platforms. 

So, one of the big values it brings to the table is load out and the ability to deliver weapons to the theater. So, instead of having a small number of weapons on the bomber platforms, we can put weapons -- large numbers on the bombers as well as the fourth- and fifth-gen fighters, and, so, we can bring a lot more to the table as far as platform compatibility and flexibility. 

The other -- the other thing is that it's easier to integrate a seeker on a -- on a cruise missile. And so, the ability to use a cruise missile for attack of targets that require seekers is a value. 

DR. LEWIS: But, the boost gliders in many cases have some range advantages and some other trajectory advantages. So, that's why we -- we -- at this point we really don't want to see an either or. We actually want to see both technologies pursued, because they both -- they both play well.

MR. WHITE: It's definitely a weapon mix, and they compliment. 

DR. LEWIS: Right. I've referred to is as a kind of a high low mix, if you will, kind of the hypersonic analogy to the F-16, F-15. 

STAFF: Let's got to Patrick.

Q: Thanks. The test happening later this week -- or excuse me, this year, could you go into anymore detail about what exactly you're testing? Are you testing the ability of the system to hit a precise point on a target grid, or are you testing flight and operation in the air, or what exactly will you walk with in a test having learned?

MR. WHITE: So the test objectives for the upcoming test that you're -- that you're referring to, FE-2 [Flight Experiment 2], have to do with the hypersonic glide body -- the common hypersonic glide body and the ability of that glide body to execute a mission consistent with the future -- future weapon application.

Q: So does that mean shooting at the specific ...

MR. WHITE: I'm just going to leave it at that. All the things -- all the things from beginning to end that you think you might want to do with a weapon configuration we will demonstrate in that test. 

Q: Yes, all right.

MR. WHITE: So, I think we're at Theresa.

Q: Yes. Therese Hitchens, Breaking Defense. I'm a little bit confused about exactly what the TBG program is doing as Dr. Roper said it was kind of the precursor for the Arrow program. But it's a DARPA program. Is the Air Force the only customer that you're seeing now? Has this like narrowed down to this is dedicated to an Air Force program taking over?

MR. WHITE: The -- the primary program that is the weapon prototype transition for TBG is the Air Force Arrow program. But there is DARPA work going on to look at using alternative launch platforms and alternative basing means for the TBG glide body. It -- it -- those systems are not funded to do weapon prototype transition as of yet.

DR. LEWIS: Right. But don't be surprised if you see eventually evolution of the TBG program into other systems.

Q: Into other services?

DR. LEWIS: Yes. Yes.

Q: Thanks. Aaron Mehta with Defense News. Thanks for doing this. You -- Mark, you mentioned at the top the industrial base and that being an aspect that you're looking at as well. 

Can you speak to your view of the industrial base as is now and whether it kind of has the capability to develop and eventually produce the type of hypersonic weapons and the quantities that you're looking for? And if it's not at that point now, where do you think that needs to grow?

DR. LEWIS: So we're actually doing that study right now. So Under Secretary Lord set up a hypersonic war room that I'm right now co-chairing with Assistant Secretary of Defense Kevin Fahey.

And we are probing those exact questions, right. What is the state of our base? Is it positioned to produce at the scales that we're anticipating? And there are lot -- lot of -- lot of moving parts to that. We obviously can -- we're obviously in a position now to develop the concepts, we develop the prototypes.

But producing at scale, as you know, is a -- is a different proposition. You know I'll give you this one example. As we pursue air breathing systems, we're looking at what are the technologies associated with producing a supersonic combustion scramjet engine?

What are the -- what are the -- and it's not just materials. It's -- it's production capabilities, manufacturing capability, high temperature materials is obviously another one that we're -- we're really interested in. What are -- what are capabilities now and moving into larger -- and moving into such of numbers that we're ultimately envisioning?

If I could also say, you know another important piece of this is -- is workforce. And to then that end we've got a really strong focus on the universities. So Mike's team is putting together a university consortium that is hoping to, you know, leverage the best and the brightest in the university community.

And hypersonic funding at the university has tended to be a somewhat periodic -- it suffered periodic cycles. There's this 15-year periodicity when we drop a lot of money in the universities, and then our programs go away and we stop doing it.

We're looking to get out of that cycle. We're especially interested in leveraging parts of the university community that are, if you will, the nontraditional players. The -- the folks who haven't -- haven't done, you know, the basic high-speed fluid mechanics maybe that can bring other -- other capabilities to their guidance navigation control material development, systems engineering.

And we think it's important not only to -- to -- for -- for development concepts but -- but obviously to make the work force available in industry as -- as well as in our government laboratories. 

Q: Can you tell us when you think that study might be done and just, gut-level, I know it's something you're working on, but, I mean do you feel comfortable?

DR. LEWIS: So we're in a pretty short-time fuse with that. So we're looking next couple of months to have that industrial base war room kind of start delivering its -- its initial reports. Where -- we just started on the endeavor, as -- as I mentioned, I suspect it will also be an evolving -- it'll be an ongoing activity. We need to continue engage with our industrial partners. 

You know we're looking for -- honestly we're looking for, you know, critical -- critical nodes in -- in the supply chain, right. We want to make sure that we're -- we're -- we're not just at the tier one suppliers but we're looking, you know, what other suppliers are necessary to -- to provide it's scale. 

MR. WHITE: And we're -- we're also making -- looking to make critical investments in advanced techniques and capabilities that get affordability into the equation right -- right from the start.

DR. LEWIS: Right, exactly. 

STAFF: Let's go over here.

Q: Hi, Abraham Mahshie, the Washington Examiner. Thank you for joining us, and please forgive me for not knowing the subject so well, but how is that Russia already has this capability and where are we in our development compared to where they're at now?

MR. WHITE: Yes, I think that's a great question. That's one we got a lot, really.


MR. WHITE: And it really has to do with one of the comments I made earlier in that -- in -- you know in past decades we've been world leaders in hypersonic technology, but we have consistently made the decision to not transition that to weapon applications and build weapon systems out of hypersonic technologies that we were working on in the laboratory.

The Russians and the Chinese, quite frankly, have both done that, and they've done that quite a number of years ago. And, so, it's that transition to application that -- that got their efforts jump started, and that -- and that's what we're accelerating now. 

DR. LEWIS: Right. The – so, the Russians have been working in the hypersonics field for quite some time. I mean, they started around the same time that we did, and they -- they built on that and, you know, we -- we see them essentially building on their Cold -- the Cold War Soviet Union legacy.

China's a somewhat different story. So, China's come to it a little bit late in the game, but they've made some huge investments. And, I also like to say we -- we did their homework for them. All right, we -- hypersonics is a field that was basically invented in this country that we -- we did the basic research, we developed the concepts, we did the fundamental experiments.

Starting in actually in the late 1940s, and, you know, we've published extensively, and they've read our papers. So, we -- we -- we made it relatively easy for people to pick up the ball from us.

Q: Follow up to that.


Q: Why now? If we've allowed them, two adversaries, to advance their capabilities; why are we right now deciding and -- as opposed to having decided to -- to ramp this up before to weapons capabilities?

MR. WHITE: The -- I think there -- there are a couple answers to that. You know one -- one has to do with making sure that we do not allow to stand an asymmetry in capability between us and our potential adversaries. And, so, what they're doing to accelerate towards weapon transition and fielding, for that matter, we can't allow that asymmetry to stand, but, I think more importantly, the world has become a place where our great power competitors have watched us over the last several decades, and they see the systems that we've developed and matured to establish our domain dominance in space, on land, at sea, and -- and in the air.

And they have systematically developed counters to that that sometimes people call A2AD, Anti-Access/Area Denial, where they -- they have systems that -- that try to deny our domain dominance in all of those areas, and it really is those threats and those targets what are driving our investments in hypersonic strike capabilities in particular.

So, it's really driven by the build up by our great power competitors and their -- and their attempts to challenge our domain dominance.

DR. LEWIS: I -- I'd also give credit -- you know we have documents like the National Defense Strategy that kind of lays out our -- a focus on -- on peer competitors. Frankly, I think we also have leadership in this building that understands the threat, and has stepped up to the plate, if you will, and is addressing it now. 

STAFF: Let's go over here for a new question. 

Q: I know none of these efforts are supposed to have nuclear warheads, but is that something that the DOD's studying and looking into as a possibility for...

MR. WHITE: Our entire hypersonic portfolio is based on delivering conventional warheads. 

DR. LEWIS: Right. Strictly conventional. 

Q: ...Russia and China are looking into that, is there a reason why you guys are not right now? 

MR. WHITE: We do not feel like there's a need to do it. 

DR. LEWIS: Yeah. 

MR. WHITE: Our strategic and our nuclear forces, while undergoing modernization at this time, that's a separate activity from our -- our hypersonic activity. 

DR. LEWIS: Yeah. Honestly it's not the value that we -- we don't see value. 

Q: Hi. Yeah, hi. So follow-on to that, the strategic implications. We're -- you know, we've talked to people who say that this is potentially destabilizing, in that it -- in -- you know, through the -- the reaction time and the ability to evade defenses, that it's -- incentivizes the first strike option. 

You know, I know that's not quite in your lane, but I'm sure you have thoughts about it and you know, how does this affect that -- that balance? 

MR. WHITE: Well, I certainly think that it's more destabilizing if they have them, and we don't. And so, you know, in order for us to be able to be -- to remove that asymmetry I described to you earlier and you -- with -- we have to be able to counter with similar capabilities when the time comes. 

And then there are a set of -- of targets and -- and missions that you -- you really need these systems to be able to accomplish, and, if you can't accomplish those missions, then you lose the deterrence of our broader forces, and, without that deterrence, I believe that's more destabilizing than if you have a deterrent. 

So, you know, the first real objective is to make sure that we are holding adversary capabilities at risk and we maintain our military deterrence and our strategic deterrence with our warfighting capability. 

STAFF: So let's go to Patrick and then to John and then someone who maybe hasn't asked a question after that. 

Q: Thanks. A quick question on the Defense Regional Glide Phase Weapons System interceptor. So the request for RFP [Request for Proposals] is out. Assuming that you get in the papers that you like, what are the milestones that you're looking for – for - that in the years ahead? And are there any lessons to be learned from previous interceptor programs like RKV [Redesigned Kill Vehicle] that you can apply to this, do you think? 

MR. WHITE: Yeah, I think -- I think there's a lot to be learned, but I will -- I will just offer that it's a very different problem than exoatmospheric intercept. You know, intercepting hypersonic systems within the atmosphere presents significantly more challenge than intercepting ballistic missiles out in space, so there's considerable technology maturity that's necessary. 

So, the Regional Glide Phase Intercept program is really focusing on identifying and maturing the technologies associated with the interceptor necessary to intercept hypersonic systems with their high speed and maneuverability within the atmosphere. 

So, there are a series of milestones in place to look at that technical maturity and then to demonstrate that technical maturity through a series of flight test demonstrations moving towards identifying a preferred concept for ultimate weapon interceptor development. 

Q: …(inaudible) demonstrations schedule, do you imagine? 

MR. WHITE: Mid-'20s is what we're shooting for. 

Q: Yes. Can you talk about investments that are being made in wind tunnels? And you're going very fast...

DR. LEWIS: Yeah. 

Q: ... are you -- are you at risk of outrunning the capability of the infrastructure to -- to test what you develop? 

MR. WHITE: Yeah, that's a...

DR. LEWIS: Yes. Yeah, we love that question. 

MR. WHITE: ... great question. 


MR. WHITE: So our -- our national T&E, test and evaluation infrastructure, is managed through the Test Resources Management Center. They have responsibility for significant investments we're making in -- in test and evaluation for both ground tests and flight tests. 

So as you might imagine, with the number of programs and the pace of testing necessary to mature those programs on the ground, we'd need additional wind tunnel capabilities, and we're making some investments in that -- that direction, primarily at the Arnold Engineering Development Center in Tullahoma, Tennessee, the Air Force facility that houses many of our hypersonic wind tunnels, including some of our hypersonic facilities that allow us to do Arc Jet testing or very high-temperature testing of materials. So, we have some investments that are going in there. 

And then we're also making significant investments to open up the aperture relative to what we can do for flight testing, where we do that flight testing and the techniques that we use to gather data and do telemetry and all the things necessary to handle the high pace of testing, coming forward. 

DR. LEWIS: Yeah, so you know, we've had some -- some good news stories. The U.S. Air Force has recently upgraded its Hypervelocity Tunnel Number Nine up in White Oak, Maryland. They've taken from a Mach 14 facility to a Mach 18 facility. 

Our friends at NASA, down at NASA Langley have upgraded -- have been working on upgrading their nozzle for their eight-foot tunnel, which was one of our prime engine -- high-speed engine testing facilities. 

We've got other facilities going in around the country, including some -- some very respectable facilities going in in universities. University of Notre Dame, for example, is building a quiet supersonic tunnel, which is essential for understanding how boundary layer -- how the flow right near the surface of a vehicle behaves. 

But as Mike said, we've -- we've got a very aggressive schedule. We are pushing the limits of our test capabilities, especially if we're flying at the rate that we hope to be flying. And we're -- we are cognizant of the problem and addressing it.

Q: And test ranges, where -- where will the initial ones be, do you think? Is it over the CONUS or out in the ocean?

MR. WHITE: We're flying mainly in the Pacific, so out of PMRF [Pacific Missile Range Facility] for the longer-range flights and then off the coast of -- the West Coast for the shorter-range flights. 

DR. LEWIS: Right. 

STAFF: So we've got a couple of minutes left. Anyone else who hasn't maybe had an opportunity to ask a question? Quiet group, all right. 

Q: Great. So you know, fundamentally, you know, where we are today, I mean, we're a couple years from fielding LRH -- LRHW ARRW...

DR. LEWIS: Yeah. 

Q: ... even after that IRCPS [Intermediate Range Conventional Prompt Strike]. But I mean, I've talked to physicists -- and you know them -- and I've talked to you. You know, the -- being able to predict the -- the, you know, transition to turbulent flow, you know, the materials that are required and the development of them, being able to mass-produce them, inlets for air cruise -- these all seem like, still, open questions in the research community. 

You know, how close are we really to solving those things? We're getting to what would normally be considered like a mature capability like JASSM [Joint Air-to-Surface Standoff Missile], or...

DR. LEWIS (?): Right. 

Q: ... you know -- you know, these things that we know, they aren't science. 

DR. LEWIS: So, I would say we're -- actually, the technology is frankly quite mature. So you talk about inlets for example. So we -- we flew a scramjet-powered system for long duration starting in 2010, that was the X-51 configuration. And, you know, the key technologies -- not only the inlet, the integration but also the engine integration, making -- building an engine that was actively cooled by its own fuel. 

We showed we knew how to do that a decade ago, and we've had a decade's experience of investments to -- to take that forward. 

You know, materials are always a challenge, but our knowledge of -- of boundary layer flows, for example, when a flow is going to go from laminar to turbulent is far, far more sophisticated than it was even just a few years ago. 

And in part, that's been informed by -- by some of the past programs that we've done. You know, I'll highlight the work that we've had done at the Air Force's Tunnel Number Nine, that hypervelocity tunnel that I just mentioned. They've done an exquisite series of tests, looking -- helping us understand the behavior of flow on the surface of a vehicle, heating effects on the surface of a vehicle. 

We've also improved our diagnostic technique, so if you look at the diagnostic tools we have available today in our wind tunnels, in our flight tests, we've come a tremendous distance from where we were 10 years ago. 

So we're really very confident. We -- we think it's -- it's -- you know, I don't want to -- I don't want to be -- I don't want to misrepresent the fact there's still development under way, but we have tremendous confidence in the ability this technology is to perform as expected.

STAFF: Aaron?

Q: So this is kind of a rejection question, which I know you guys love, but...


... so we have all these different programs going on. We know that there's been a lot of talk about making sure the services are talking to agencies and...


Q: ... everyone's working together, et cetera, et cetera. We saw the Air Force cut one for budgetary reasons. I'm wondering going forward, are you guys expecting to have a number of hypersonic programs to perhaps continue to grow as certain areas need to be developed, or are you envisioning that mid-2020, towards the end of the decade, we get down to maybe one or two hypersonic weapons which is shared by everyone?

DR. LEWIS: So, I would say, no. It's not going to be one or two hypersonic weapons. And coming back, hypersonics isn't a single thing. It's a range of capabilities, right? It's intermediate range. It's long range. It's things coming off of ships. It's things coming off of trucks. It's things coming off of wings of airplanes and out of bomb bays. It's a full range of capabilities.

So no, I don't - I don't expect us to zero in on just one or two things and stop there. I expect development efforts to continue. At the same time, we have a very strong focus on delivering real capabilities, getting these things out of the laboratory, getting these things out of prototypes, and getting these into the hands of the warfighter, and that's our primary focus now.

MR. WHITE: Yes, I would agree 100 percent with what Mark just said, and I'd urge you think about war fighting capability versus hypersonics as a thing as Dr. Lewis just said, and if we project the adversary capability that I described to you earlier to challenge our dominance in the war fighting domains, that's not going to get easier. It's going to get harder, and I think there will be more and more drive for advanced weapon capabilities that you can feel with these hypersonic systems. I see it being more of a proliferated capability than just a niche kind of thing.

STAFF: So we're right at the end of our time. Sylvie, you just came in. Did you nod to me like you wanted to ask a question?

Q: I would like to ask a question.

STAFF: Please.

Q: Thank you. Actually, you say that these, they would challenge, you know, dominance - the U.S. dominance, but there are some experts who say that it's not really true that you - that the hypersonics are not impossible to detect and impossible to stop and that actually you could keep the dominance without all these expensive products.

DR. LEWIS: So you can - you can detect hypersonics, but it's very difficult. The nature of these systems, the way they fly, they way they operate, their trajectories, it makes it very, very challenging. And, also, even if you can detect them, it's very difficult to respond, because you don't have a lot of response time. All right, in military terms we like to talk about the OODA loop - observe, orient, decide, and act. Getting inside an opponent's OODA loop, getting inside their decision - their decision processes makes it difficult for an opponent to respond.

Well, these things capture that because they're moving - the time scales are so small. Having said that, we certainly have an emphasis on the defensive side. We are looking at ways of doing the detection. Air Space Development Agency, for example, is very much focused on technologies that would help us detect these systems.

Similarly, once you detected, then stopping them.  Yes, we think there are ways to stop them. We have defensive systems, but they're not going to be 100 percent effective. More importantly, I'd say that hypersonics is something that we'd want to pursue even if adversaries were not or potential adversaries are not. It's a military capability. I put it in the category very much as when we developed stealth capabilities, stealth technology.

You know, with stealth, our systems were invisible to radar. With hypersonics, our systems are perhaps visible, but they're harder to stop, and that's the advantage that they bring to the battlefield.

STAFF: So, ladies and gentlemen, we're out of time. We ran a little over, because we were a little late starting. If you've got any questions that you did not get to ask, please send them to me, and we'll try to get responses back to you as quick as we can. So, thank you very much for joining us. Gentlemen, thanks for being here.

MR. WHITE: Thank you.

DR. LEWIS: No, thank you. Thanks a lot.