Skunk Works unveil SR-72 concept

[colay]

LM and Aerojet Rocketdyne are to be congratulated for investing the time and resources to design an engine to make possible a Mach 6 SR-71 replacement. With sequestration, the timing sucks but perhaps the lure of a hypersonic ISR/Strike capability will garner USG funding for a demonstrator program before the decade is out.

Exclusive: Skunk Works Reveals SR-71 Successor Plan

 

[My2Cents]

Interesting concept, but given the improvements in SAMs it may not be very survivable.

There is also the question of whether or not it can fly slow enough to use existing aerial tankers.

 

[StobieWan]

There'll be a special tanking requirement like the Blackbird - the article says it'll fly on turbines up to and beyond Mach 3 so providing it can cruise reasonably economically (ie, it's not burning gas faster than it can tank it) at normal tanking speed/alt) then you're on.

The Blackbird was a special qualification for the boom operator and the tankers were always dedicated due to their having to carry the unique fuel the Blackbird ran on (which was rated for wide extremes of temperature)

Ian

 

[CB90]

Air Force does have a requirement for NGB they've been looking to fill...but it's currently written for a subsonic stealth bomber.

If they'd be willing to stretch the time horizon quite a bit to develop this into a future national asset strategic bomber, we might have something there. That said, it'd likely be a pretty expensive way to deploy a very niche capability, but it'd also be one that's nice to have when you do in fact need it.

"Speed is the new stealth."

 

[Bonza]

Interesting concept, but given the improvements in SAMs it may not be very survivable.

There is also the question of whether or not it can fly slow enough to use existing aerial tankers.

You don't think an extremely high altitude aircraft moving at mach 6 and surely possessing some degree of signature management (though I understand it's going to light up like a christmas tree in terms of thermal signature) is going to be survivable against SAMs?

Remember it's not just the performance of the missile, it's the performance of the entire system leading up to the missile launch, so you have to detect the target, pass that to a system capable of producing practical targeting data, then pass that data to the missile, then comes the launch - the length of that cycle has to be short enough to defeat a target that's already moving at mach 6, at high altitudes, and is very likely to be jamming/spoofing like crazy (my assumption there but I'm almost certain a decent EW package will be part of the solution given a similar thing was done with the Blackbird).

You might be right too, but looking at all the activity around hypersonics at the moment and based on some talk I've heard here and in other places I wouldn't be surprised if military minds are convinced hypersonics are sufficiently survivable to form part of several next generation solutions.

 

[StobieWan]

A missile (or in fact anything else trying to intercept an aircraft) needs a decent hedge in terms of speed on the target as well - if the target is doing Mach 6, the interceptor will likely need a margin of about 1.5x that to be useful.

Anything less and the intercept range dwindles considerably - what that speed does is shrink the effective radius of all the SAM sites under the flightpath, while at the same time cutting into the time available to generate sorties against it, or engage with SAMs.

I'd imagine one of these popping up just ahead of a LO attack would be a real shock to the system.

It's an interesting development and I'll be interested to see if it flies - there's a lot of competition for funds however, with NGB already under pressure to avoid becoming gold plated.

 

[gf0012-aust]

I'm on the SR71 Blackbird email group, the habu pilots are having a grand old time telling war stories about triple booming Hanoi (ie 3 x SR71's doing a synchronised sonic boom overflight over Hanoi

Not a lot of stress coming out of the group about current SAMs being able to intercept in time

The lead time and data acqu and maint to vector on Mach 6 is not within any countries capabilities at present

 

[gf0012-aust]

You might be right too, but looking at all the activity around hypersonics at the moment and based on some talk I've heard here and in other places I wouldn't be surprised if military minds are convinced hypersonics are sufficiently survivable to form part of several next generation solutions.

Wookie and I were tied up with hypersonic projects a few years back, the double threat was always about the hypersonic chariot throwing hyersonic rocks

Certainly from the work we did and the people we were involved with - hypersonics was way up there and was very much going to be part of the future air warfare solution.

the only divergent point when we were involved was whether they would be manned or unmanned - and the view was that they would be unmanned as the control system maturity would be well advanced by the time they went gold - both have their benefits depending on mission set

 

[Bonza]

I'm on the SR71 Blackbird email group, the habu pilots are having a grand old time telling war stories about triple booming Hanoi (ie 3 x SR71's doing a synchronised sonic boom overflight over Hanoi

Not a lot of stress coming out of the group about current SAMs being able to intercept in time

The lead time and data acqu and maint to vector on Mach 6 is not within any countries capabilities at present

Thanks for that clarification GF (and the additional info in your second post), I had a feeling that cueing a SAM launch at a target moving so quickly with the realistically expected supporting systems/assets would be a huge undertaking in and of itself. Nothing's perfect but I wouldn't expect survivability against SAMs to be the chief challenge with this kind of platform.

 

[colay]

The USAF Hypersonics Roadmap envisions a demonstration of a turbine-to-dual-mode-ramjet/scramjet system capable of Mach 5+ by 2020. By no coincidence, the bruited SR-72 would fit the timetable quite nicely.

USAF

The development of a hypersonic aircraft “is probably a significant step up in the technology required and risk over weapons,” says Clay. “So it is a slower undertaking and much more expensive. We've laid out a reasonably paced program, which can be accelerated if the need arises.” The initial speed of Mach 4-plus was defined at the first meeting in December 2010. “Since then, we've migrated up to a higher speed of Mach 5,” he says.

A high-speed mission analysis research process was used to define the technology challenges and, along with studies of new concepts and vision vehicles, drove the desired speeds higher. “All of the studies have been leading us in the direction of Mach 5 and above. We've started to lay out what are the technologies required to make that real,” Clay says.

The outline plan calls for demonstrations of a turbine-to-dual-mode-ramjet/scramjet transition system around 2020.

 

[StobieWan]

I'm on the SR71 Blackbird email group, the habu pilots are having a grand old time telling war stories about triple booming Hanoi (ie 3 x SR71's doing a synchronised sonic boom overflight over Hanoi

Not a lot of stress coming out of the group about current SAMs being able to intercept in time

The lead time and data acqu and maint to vector on Mach 6 is not within any countries capabilities at present

I must have read three or four books on the Blackbird and I sit amazed every time I leaf through one of the ones on my bookshelf. The reports from the Libya flights where they were tracked by SA-5's, took a look at the plot and just opened the taps to M 3.24 and held it there til the bad missiles went away say a lot. Given the SA5/S200 is quite a bit quicker than an SR71 it does hint that shooting them down wasn't a slam dunk exercise in missile speed vs target speed.

 

[Haavarla]

Ofcourse that is directly linked to that time and the performance of the seeker of those missiles system.
Fast forward today, the capability of many countries air and Space defence has increased on platform, system and software level.

The intercept speed of S-300 and S-400 missiles has not changed much from the S-200, but detection and guidence systems has.

Even at M +3.0, the threat of being downed has increased over the years.

Further more, the "low cost" and "hypersonic capability" term does not coexist wery well. History has shown us that.

 

[Feanor]

Not a lot of stress coming out of the group about current SAMs being able to intercept in time

No of course not, nothing today is even in the ballpark. But this aircraft is expected to enter service in the 2030 timeframe... development is only planned to start in 2018. Things will be quite different then, and that's assuming the program is on track. With budget cuts, and rising costs we could be looking at an even further date. The question then becomes, how survivable will this aircraft be in 2040?

Thanks for that clarification GF (and the additional info in your second post), I had a feeling that cueing a SAM launch at a target moving so quickly with the realistically expected supporting systems/assets would be a huge undertaking in and of itself. Nothing's perfect but I wouldn't expect survivability against SAMs to be the chief challenge with this kind of platform.

It wouldn't be SAMs specifically, or SAMs exclusively, but a complex IADS with modern air-air as well as surface-air capabilities. Something like this is not particularly needed if we're bombing Iraq or Libya for the third time. Even the brand new Venezuelan IADS is comparable to what the Soviets operated in the late 80s. If those kinds of threats were the primary concern, something like this would be completely unnecessary. This suggests that we're talking about Japan, or Russia, or China, or a major European power.

I must have read three or four books on the Blackbird and I sit amazed every time I leaf through one of the ones on my bookshelf. The reports from the Libya flights where they were tracked by SA-5's, took a look at the plot and just opened the taps to M 3.24 and held it there til the bad missiles went away say a lot. Given the SA5/S200 is quite a bit quicker than an SR71 it does hint that shooting them down wasn't a slam dunk exercise in missile speed vs target speed.

Well the question is at what point did the S-200 detect and engage the SR-71? If I understand correctly the no escape zone shrinks together with the engagement envelope.

 

[gf0012-aust]

Well the question is at what point did the S-200 detect and engage the SR-71? If I understand correctly the no escape zone shrinks together with the engagement envelope.

The soviets were planning well ahead and anticipating the shots - and volleying those shots as the SR-71's didn't even bother varying their regular flight paths.

Despite knowing the tracks, despite knowing that the aircraft were over flying with swiss watch regularity, they never got close - and in the 3 major and most concentrated SAM spaces in modern history.

 

[gf0012-aust]

The intercept speed of S-300 and S-400 missiles has not changed much from the S-200, but detection and guidence systems has.

CREF prev

Even at M +3.0, the threat of being downed has increased over the years.

Mach 6 is exponentially very very different to deal with

Further more, the "low cost" and "hypersonic capability" term does not coexist wery well. History has shown us that.

History is showing that its cheaper to achieve and happening faster than thought.

The last 5 years have shown exponential advances at the weapons system level

Even 5 years ago when Wookie and I were involved with hypersonics it was pretty clear that the multi stage development model was on track.

Nobody I know of was getting excited about laser and energy weapons in comparison - but they were pretty committed on how hypersonics were the more flexible solution. Very few countries have the capacity to pull all the requisite tech together to make a functioning weapon, let alone weapons systems, let alone weapons platform, let alone the complete tech solution.

 

[StobieWan]

No of course not, nothing today is even in the ballpark. But this aircraft is expected to enter service in the 2030 timeframe... development is only planned to start in 2018. Things will be quite different then, and that's assuming the program is on track. With budget cuts, and rising costs we could be looking at an even further date. The question then becomes, how survivable will this aircraft be in 2040?



It wouldn't be SAMs specifically, or SAMs exclusively, but a complex IADS with modern air-air as well as surface-air capabilities. Something like this is not particularly needed if we're bombing Iraq or Libya for the third time. Even the brand new Venezuelan IADS is comparable to what the Soviets operated in the late 80s. If those kinds of threats were the primary concern, something like this would be completely unnecessary. This suggests that we're talking about Japan, or Russia, or China, or a major European power.



Well the question is at what point did the S-200 detect and engage the SR-71? If I understand correctly the no escape zone shrinks together with the engagement envelope.

The SR71 was engaged by something in the region of 270+ missiles over it's career - in a lot of cases, the initial tracks might have been set up by spy trawlers in the North Sea, followed by OTH-B systems - they could usually see them coming from well over a hundred miles away.

In most cases, the aircraft didn't even change course - they could dance with SAM's all day long - and occasionally did.

I'm lucky enough to have some of the program documents from the Valkyrie - papers from one of the program directors given to me by his son, who knew I was a fan and there are a couple of good diagrams of how far your engagement range shrinks when something comes in at M1, 2, 2.5 and 3. Travelling that fast really does cut into your reaction times. The USSR layered aircraft on speculative tracks, threw entire airfields up at the beast and at least one Habu pilot is on record as stating "I cannot comment on any missions I performed, but I can confirm that in any mission we were tasked with, we were *never* denied access" - I'm paraphrasing from memory here but the confidence stuck out.

Mach 6, you're not doubling the difficulty of prosecuting the threat, you're more or less squaring it.

 

[Haavarla]

CREF prev



Mach 6 is exponentially very very different to deal with



History is showing that its cheaper to achieve and happening faster than thought.

The last 5 years have shown exponential advances at the weapons system level

Even 5 years ago when Wookie and I were involved with hypersonics it was pretty clear that the multi stage development model was on track.

Nobody I know of was getting excited about laser and energy weapons in comparison - but they were pretty committed on how hypersonics were the more flexible solution. Very few countries have the capacity to pull all the requisite tech together to make a functioning weapon, let alone weapons systems, let alone weapons platform, let alone the complete tech solution.

When we debate Supersonic and Hypersonic manned Capability, then it is not something that can be fixed, tweaked or bypassed With systems and software.. you need a delicate platform and a very spesific type of engine.

Just how would you go about designing an hypersonic platform that can slow Down, decent and do tanker Refueling?
How large internal volume of Fuel would you need?
What kind of MTOW would you need?
What kind of fuel would you need?
What kind of Alloy material would you need on such platform.

I don't expect any answers, but my point with these questions transends into Ultra high cost.

Past drawing Board towards the real thing is where the $ rules.
If you want to mix low cost With Hypersonic, then make it unmanned rocketlike platform, launch it to near Space altitude, and make it a one-way platform.

 

[gf0012-aust]

metallurgy, compound tech and fuel management have come an extraordinarily long way since the A12 was first run up.

We're over 60 years down the track.

you seem to be unaware that the fuel efficiency of some of the hypersonic engines improves the faster they travel

we're not talking about normal thrust, fuel states, fuel fractions here....

as I said before, when Wookie (defprof in here) and I were involved the debate was less about the tech and more about the manning issues - and some of those were around legal issues rather than efficiencies of management

you're wrong on the issue of ultra high costs. we were dealing with compound ceramics which could be made with 3D printers and were a 1/10 of the price to fab up the prev metals based solution (we were using 3D printers in 2005 and fabbing up complex heat resistant components even then.

Bear in mind that the majority of hypersonic developments stemmed from private funding - the appetite to willingly spend money without return is already demonstrated

 

[Shanesworld]

metallurgy, compound tech and fuel management have come an extraordinarily long way since the A12 was first run up.

We're over 60 years down the track.

you seem to be unaware that the fuel efficiency of some of the hypersonic engines improves the faster they travel

we're not talking about normal thrust, fuel states, fuel fractions here....

as I said before, when Wookie (defprof in here) and I were involved the debate was less about the tech and more about the manning issues - and some of those were around legal issues rather than efficiencies of management

you're wrong on the issue of ultra high costs. we were dealing with compound ceramics which could be made with 3D printers and were a 1/10 of the price to fab up the prev metals based solution (we were using 3D printers in 2005 and fabbing up complex heat resistant components even then.

Bear in mind that the majority of hypersonic developments stemmed from private funding - the appetite to willingly spend money without return is already demonstrated

Absolutely, some of the first uses of sintered powder metallurgy was with tungsten and titanium. In the range 1000 watt solid or shielded laser but you got self supported and complex internal geometry and intricate part fit previously unobtainable with casting, machining or assembly. Very little in the way of dies, jigs or moulds too. And a much reduced workforce with generally greater consistency of product if your processes are good.

A company whose name I forget now in Germany is or was experimenting with the laser deposition machines mounted on wirelessly networked robots that would work with a set of beacons to mark their boundary and give datum. From that, if it works you have a 3-D printer factory that if you tried hard enough could build a truck, a building, even a ship. Limited only by the size of the flat floor and the range of your robot/beacon combination. I think it is still conceptual but might point where things head.

There seems to be a lot of mysticism around some ceramics and carbon carbon type products. I'm abit the same until a supplier showed me how they produce the carbon carbon nano tube product they sold us. You aren't too far off if you have closed door fire. Simplification but basic principle applies.

 

[Haavarla]

gf0012-aust;270910]metallurgy, compound tech and fuel management have come an extraordinarily long way since the A12 was first run up.

We're over 60 years down the track.

you seem to be unaware that the fuel efficiency of some of the hypersonic engines improves the faster they travel

we're not talking about normal thrust, fuel states, fuel fractions here....

The A-12 is not an Hypersonic platform. The A-12 maxed out at a certain sustained speed due to a number of physicaly limits.

I'm am very well aware of what kind of challanges and what type of engine is requirerd for hypersonic speed.

A Ramjet or Scramjet engine if you like.
The insane challanges With fitting such engine on a Hypersonic platform is very Clear.
You can't sustain flight With only one type of Engine. You need two. So far we are using solid rocket fuel engine to accellerate the platform up to needed Ramjet speed regime.
Solid Rocket fuel and JP-7 fuel.. yep, we got two Ultra high cost compound right there.
Seriously, we are not anywhere near developing a combined Rocket engine/Ramjet engine.. let alone an jet engine/Ramjet engine.
How about making the Ramjet engine workable first?

So what are we left With, a hypersonic platform With two different kind of engines. Might as well design an Space ship and fly it to Outer space, cause it is the exact same High-Tech and physical challanges NASA allways faced back in the Space Shuttle days. And everything about Space is Ultra high cost.
Wait.. ins't NASA is also engaged in the X-51 waverider program. How is that program going so far?

you're wrong on the issue of ultra high costs. we were dealing with compound ceramics which could be made with 3D printers and were a 1/10 of the price to fab up the prev metals based solution (we were using 3D printers in 2005 and fabbing up complex heat resistant components even then.

Really.. give the DARPA consortium behind the X-51 waverider program a Call and explain to them how its done then.

The critical design review (CDR) of the X-51 vehicle, completed in January 2007, cost around $70m

As i said, past PowerPoint and drawing Board is where the challanges turns into real $.
2013. How much has the Hypersonic R&D cost so far?

Bear in mind that the majority of hypersonic developments stemmed from private funding - the appetite to willingly spend money without return is already demonstrated

Privat funding yes, Which does not make it any less costly. You still have to make it work.