This week's installment of AOL Defense Ignorance is titled: "Will Stealth Survive As Sensors Improve? F-35, Jammers At Stake". The first half of the title is a legitimate question asked continuously by defense planners, intelligence agencies and engineers. (The answer BTW, is found in the continued fielding and reliance on Low Observable weapon systems: So,Um, Yeahhh.) The second half of the title is 'Oh Noes!' melodrama.
~Sigh~ Where to begin? I know!
The Experts (one is not)
Freedberg grossly understates the qualification of the real expert who believes that 'stealth' still has a future, retired AF LtGen Dave Deptula, by merely identifying him as:...a member of AOL Defense's Board of Contributors and the first man to serve as the Air Force's head of Intelligence, Reconnaissance and Surveillance.If I had to list General Deptula's qualifications on this subject I think would have perhaps listed a few things missing that are more than just a little relevant to the topic at hand. Things such as General Deptula was a senior member of the 'Checkmate' organization that conceived what would become the Desert Storm air campaign plan, and from there he became the principal attack planner for the Desert Storm coalition working out of the 'Black Hole' in Riyadh. His General Officer assignments prior to last one where he was Air Staff over AF IS&R (2006-2010) included (going backward in time):
- 2005-2006, Commander of the General George C. Kenney Warfighting Headquarters (P), and Vice Commander, Pacific Air Forces
- 2003-2005, Director of Air and Space Operations, Headquarters Pacific Air Forces,
- 2001-2003, Director of Plans and Programs, Headquarters Air Combat Command, Langley AFB, Va.
Freedberg then compounds his error by trotting out a non-expert 'expert' in a rather egregious fallacious appeal to authority: "long-time stealth skeptic" Norman Friedman "an award-winning military analyst and author with a degree in theoretical physics". While Dr Friedman has a PhD in 'Theoretical Physics' that predates the information age, his forte since that time seems to be the research and publication of 'serious' books on the developmental histories of various classes of naval ships. I would cut Freedberg some slack on using Friedman, if Friedman's contribution to the article demonstrated any insight into the subject of low observables. Instead his 'argument' consisted of nuggets such as:
"the Air Force went hot on stealth because it was a way of showing that pilots could survive" in the face of improving anti-aircraft defenses known as "dougle-digit [SIC]SAMs," the highly capable air defense systems that the Soviet Union began developing in the 1980s.I can't say that I've ever seen a fallacious appeal to authority within a fallacious appeal to authority before, but there you go: 'the CNO sez' so it must be true'. Freedberg uses this bit as a segue to regurgitate some of the CNO's embarrassing comments from last July that I took him to task for here, and then Friedman simply parrots some of the CNO's other ill-informed commentary:
"A lot of this is about whether pilots stay in business," Friedman went on. Especially outside the Air Force, he said, "I would suspect that people worry about stealth not being nearly as good as people claimed it was. The CNO in Proceedings said as much."
"You can't make something disappear, all right?" echoed Friedman. "What you can do is reduce the signature you get back [on the enemy's sensor screens]. More powerful processors buy you back part of the signal" – and thanks to Moore's Law, the processing power available to do that doubles every 18 months. The more powerful the processors and the more sophisticated their algorithms, the more effectively they can sift meaningful data out of the static. And no matter how stealthy an aircraft is, it still makes some noise, it still emits some heat as infra-red radiation, and – most critically – it still reflects back some portion of an incoming radar beam.Well I pretty much slapped this down in July too, but perhaps it is worth repeating essentially the same scenario and questions I used the last time. Questions that perhaps Dr. Friedman would have instantly thought of IF his background was in Applied rather than Theoretical Physics.
As to the 'signature' statements:
You are in Command of the control center of an Integrated Air Defense System. I am flying along at 450 Kts at 45000 ft in my Acme Stealth Bomber. At point X and Time T, one of my ‘angles’ and/or ‘aspects’ is aligned such that my signature is detectable by one of your ‘sensor systems’.
At time T plus 1 microsecond later, that ‘angle’ and/or ‘aspect’ is no longer aligned such that it can be detected. DID your system detect me in the first place? If it did, what useful information did you collect to even process as to my range, altitude, heading, and speed? (Hint: Probably Zilch, Nil, Nada.)
Did I mention that the RCS signal return you were able to detect was the equivalent of a (at most) large insect? How many large insects, or birds, bats, or chunks of vegetable matter are flying through your network airspace at any given time? Know anything about ambient RF noise? What are the chances your system filters out that 1 microsecond of signal as random noise? (Hint: Pretty Frickin' High - and all the processing power in the world doesn't help you if you are integrating a Zero) My RF ‘fuzzball’, in all frequencies where the physics dictate I can be tracked, is defined by very narrow spikes and very deep nulls. My three-dimensional orientation to any and all of your sensors is changing constantly and rapidly-- even if I fly in a straight line, constant speed and elevation.
Oh, did I mention my tiny signal was received among all the other combat environment RF activity... including my onboard EW and offboard jammer support?
BTW: Did I mention this is ‘day one’ and your radars and control nodes are the primary targets?As to Dr Friedman's unoriginal gnashing over IR emissions, I'll just paraphrase myself again:
Infra-red tracking is a short range capability. Just like for visible light digital detection systems, digital infrared detection requires at a minimum 1 pixel with detectable contrast to surrounding pixels. (Analog systems, such as the human eye require 1/2 arc-seconds 'width' contrasting against the field of view).These are clear-sky minimums. Any kind of moisture in the air between target and detector, or behind the target will reduce detection range. Typical operating altitudes commonly have a lot of this moisture equal or above them.
The total target contrast is attenuated by the physical properties of the atmosphere itself. The major constituent gases 'absorb' Medium IR frequencies, and those just happen to be the part of the bandwidth emitted by the jet exhaust. The Low IR and High IR bands aren't absorbed nearly as much, but that is OK, because the emissions are much lower as well -- so the management of these emissions is accomplished by selection of outer mold line shaping, coating colors and surface textures.
Fear is the Mind-Killer
Deptula runs rings around Friedman, stating cogent fact after fact. Friedman merely expresses fear after fear with little or poor rationale for that fear:"The way LPI usually works is you send out a signal that looks like noise and somehow you reassemble that signal when it comes back," said Friedman. That depends on massive processing power and sophisticated algorithms – which are becoming more available to everyone. Are you so much smarter in your processing than the other guy?"Dr Friedman reveals much here. If he understood how LPI actually worked he wouldn't imply it came down to being 'smarter' in processing. The LPI radar 'knows' what type it is, the carrier frequency used at any point in time, the modulation bandwidth used at any point in time, the modulation period, the scan timing that determines where the radar beam(s) is/are pointed at any one time, and when the radar modulation pattern used begins. The air defense systems, do NOT.
Sydney Freedberg does contortions to tie this mess of an article up at the end and there's much that in comparison to the above is simply niggling nonsense.
In closing, let me also note that among the most irritating aspects of these kinds of articles is the framing of the problem as essentially 'static' stealth designs against an onslaught of rapid progress in low observable detection schemes. Neither is standing still, and neither rely solely on 'technology', they rely on technology AND tactics.
P.S. And I've yet to see anyone make a convincing case to not make a weapon system as stealthy as possible ESPECIALLY in the face of advanced air defense systems.
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