Now you see them: DARPA's Stealth Revolution (2008) [pdf] | Hacker News Reader

Now you see them: DARPA's Stealth Revolution (2008) [pdf]

darpa.mil

31 pointsgodelmachine25 comments

"Management at Lockheed’s Skunk Works soon learned of the DARPA competition. Lockheed had not been invited to participate because they had not produced a fighter in nearly 20 years and DARPA was unaware of their work on the A-12/SR-71 aircraft."

The only question lingering in my mind is what would had the been the structural shape of Lockheed Have Blue, had they had more computing power?

If they'd had both the computational power AND the numerical modeling approaches/theory that were later developed, e.g., modified method of moments, then the vehicles would look a lot more like more contemporary "stealth" aircraft, e.g., B-2, JSF, YF-23, etc. Note that it's a lot easier to get an efficient aerodynamic and low observable platform when you can appropriately harness curvature.

If you have enough interest to go beyond these documents that are "web length" and would like to delve into the engineering and programmatic details, I cannot recommend enough the AIAA book "Have Blue and the F-117A: Evolution of the "Stealth Fighter": https://arc.aiaa.org/doi/book/10.2514/4.867958 . It is easily one of the best books out there on the development of an advanced technology / rapid prototyping aircraft, and you'll marvel at how little context any of the usual web length writeups or TV shows actually give you.

"Have Blue and the F-117A: Evolution of the Stealth Fighter"

I swear to God I'd noted this book in my to-read list today itself. There's no pic attach menu available here, else I would post a snapshot of my to-read list.

Apart from that, I had also noted these two -

"Area 51 Black Jets A history of the aircraft developed at Groom Lake"

"Inside the stealth bomber"

Had you had the opportunity to read these two?

Thanks for the suggestion.

I should have given a disclaimer: if you're not a practitioner in the area or not completely interested in the details, "Have Blue and the F-117A" can be in dry in parts.

I have not read "Area 51 Black Jets"; title clearly intended for pop appeal, but hopefully it's substantial content.

I believe I read "Inside the stealth bomber" about 15 years ago and thought it was decent. Bill Sweetman is one of the better aerospace writers out there, if a bit quick to extrapolate from some data points (makes sense given he's a journalist whose trade is to discuss things about which little info is publicly available).

The recommendation for Skunk Works by Rich (I think ghostwritten by Leo Janos who also ghost wrote for Yeager) is also seconded.

There also a few choice publications of decent length on the web:

"Winning the ATF" by Sherm Mullin, PM for the YF-22: https://www.afa.org/20140207afaorg/publications/michellinsti... -> "Winning the ATF"

"B-2: Spirit of Innovation" by Rebecca Grant: http://www.northropgrumman.com/Capabilities/B2SpiritBomber/S...

Great NASA e-book series: https://www.nasa.gov/connect/ebooks/aeronautics_ebooks_archi...

The only potential thing to watch out about the NASA books is that NASA sometimes has a tendency to play up their own contributions to programs that were very joint (e.g., AF/NASA/DARPA and Industry). Small fault to find given that NASA is awesome enough to put these high-quality publications together, employ some really great historians and photographers, and make the pubs freely available. In particular, the F-16XL story ("Elegance in Flight") is one that I'd never seen told with such completeness anywhere else. The X-29, Active Aeroelastic Wing, and Low-Boom Supersonic books are also recommended.

May I ask for full name of Yeager & the books he wrote?

I've been studying about Stealth & Aerodynamics on my own for a few years now. So I don't read them just for pop appeal. Went through a few parts of "Have Blue & the F117A" yesterday, and I'm okay with it. Actually I'm excited to read it in it's entirety.

Thanks a lot for the detailed elaboration though. Gonna take a look at these books.

I would also recommend the book "skunk works" written/ghost written by the head of the skunk works during f117 design.

Let me guess before I Google.

Head of the Skunk Works was Clark "Kelly" Johnson? The Swedish engineer who designed SR71 BlackBird and who could "see through air"?

Edit - I'm wrong. The author is Ben R Rich, who is successor to Clark "Kelly" Johnson. Both served as directors of Lockheed Skunk Works.

> Head of the Skunk Works was Clark "Kelly" Johnson? The Swedish engineer who designed SR71 BlackBird and who could "see through air"?

I believe most humans can see through air. Presumably the paraphrase was something more like "see air". ;)

As for Skunk Works, it chronicles Ben Rich's involvement in Skunk Works, which spanned 1954 - 1991. Initially as thermodynamist, later as director.

It's half about U-2, A-12 / SR-71, F-117 development, and half about how to create, nurture, and sustain a high-performance engineering culture on a budget.

Would definitely recommend.

I just ordered a copy of this book. Thank you!

I'll bet. The idea that DARPA was ignorant of a fighter program by one of the largest weapons contractors in the country/world is absurd.

  > The idea that DARPA was ignorant of a fighter program by one of the largest weapons contractors in the country/world is absurd.

It's a more nuanced story. What they didn't understand was that the A-12 series of aircraft (A-12, YF-12, SR-71 and even D-21) were specifically designed with early low observables principles & materials in mind. There was a lot of classification with these aircraft, particularly due to their initial customer (CIA rather than DoD). They needed to obtain permission from the CIA to discuss the low observables aspects with DARPA.

These kinds of issues (inability to discuss relevant classified developments with other defense or intelligence entities that might benefit from knowing) is a routine and valid criticism of classification practice.

Eh, color me a skeptic on this. I just find it very hard to believe. Agree to disagree on it, as it were.

This happens all the time with classified programs.

That pesky "need to know" principle.

DARPA has dozens of projects.

http://www.technovelgy.com/ct/Technology-Article.asp?ArtNum=...

We have self-driving cars and the Internet because of DARPA. It sort of like a government sponsored X-Prize.

Self driving cars because of DARPA? Hmmmm. Interesting. Gotta read up on that.

May I ask name of the Genesis project for self driving cars?

I was the Autonomous Land Vehicle (ALV) program and it lead to the pioneering of neural networks by CMU.

https://www.youtube.com/watch?v=ilP4aPDTBPE

http://repository.cmu.edu/cgi/viewcontent.cgi?article=2874&c...

The idea of neural networks go back a lot further than CMU.

http://www.andreykurenkov.com/writing/ai/a-brief-history-of-...

I should’ve been more clear IIRC ALVINN was the first ANN based computer vision decision making implementation in the world at the time. It was also one of the first practical applications of an ANN in general.

The DARPA Grand Challenge. NOVA has a special on it. It might be on YouTube too.’

http://www.pbs.org/wgbh/nova/darpa/

Oh yes this is it!!

I was trying to remember DARPA Grand Challenge as a possible candidate for one of the DARPA programs to pioneer Computer Vision in self driving vehicles. Also had Sebastian Thrun lingering in my subconscious.

But then thought the real DARPA program that gave us self driving cars must be somewhere in 70's or 80's

DARPA needs to be unleashed on global warming. Their has to be a means of "scooping" CO2 and other green house gases out of the sky with autonmous solar powered drones and breaking them down, for instance breakdown CO2 to Carbon and Oxygen.

The idea may sound absurd but I believe it threads the needle of the GOPs love for defense spending and opposition to negative economic impacts, with everyone elses desire to save the planet.

The machine that turns CO2, sunlight, and water into sugar and oxygen is already invented.

Unfortunately, we're poisoning the most important instance (in the oceans) and clearing another (in developing countries) wholesale, leading to less biomass where there needs to be more.

Forests are coming back and have been for a while. Back in the 90s the Clinton Administration made a big deal of this during the Kyoto negotiations.

The most inspiring para for me ->

Under HAVE BLUE, Lockheed built two manned technology dem- onstrators to validate Lockheed’s pole model results. Even though these test vehicles made use of conventional o -the-shelf compo- nents and subsystems, they were truly revolutionary. Their shap- ing and materials were so important that their impact on aircraft survivability changed the way the U.S. Air Force ghts. Technologies nurtured by DARPA included RCS reduction, RAM development, infrared shielding, reduced visual signatures, low-probability-of- intercept radar, inlet shielding, exhaust cooling and shaping, and other signature reduction disciplines. First ight occurred in April 1977, and both aircraft were tested extensively. Eventually both were lost during ight test mishaps, but the results were clear. On Nov. 16, 1978, Lockheed received a contract for full-scale engineering devel- opment of what would become the F-117.

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