Alternative Stealth

How do you make an aircraft stealthy?  We all know the answer to that, right?  You carefully shape the aircraft and then apply low observability (LO) coatings.  The only problem with that answer is that today’s radars are becoming more and more capable of detecting stealth aircraft.  The radars operate at different frequencies and networked radars can compare returns and scatter (to put it simplistically) to pick out stealth aircraft.  Add to that the improvements in infrared detection (IRST) and stealth aircraft are becoming less and less stealthy all the time.

For ships, it’s a similar case of stealth being achieved by shaping and, to a lesser extent, coatings.

We’ve invested huge amounts of money into stealth and we’ve based our entire military on it.  For a relatively brief period in the 1990’s we had a monopoly on effective stealth and a major battlefield advantage.  Today, however, everyone has stealth and everyone is developing stealth detection capability.  Our advantage is disappearing.

In the near future war, two stealth aircraft are going to meet and their air-to-air weapons, having only small, relatively simple radars, will be unable to lock on to their opposite number.  At that point the engagement becomes a dogfight, no different than our WWI forefathers and the better aerodynamic aircraft will win (hmm… that F-35 isn’t looking so good now, is it?  But, I digress …).

So, is our stealth advantage permanently gone?

No.  There are alternate means of achieving stealth – something the military seems slow to recognize.  Here are some alternate means.

ECM – This is an easy one to implement and can be highly effective.  Electronic countermeasures (ECM) such as jamming, disrupting, creating false signals, etc., for the enemy’s sensors is effective and efficient.  If the sensor is disrupted, our asset gains a measure of stealth – in this case a bestowed stealth rather than an inherent one.  The challenge lies in staying current, given the pace at which the electronic signals world changes, and covering the massively broad range of signals.  Even more challenging, many weapons are built with frequency agility meaning that the ECM has to be able to counter almost the entire spectrum!  On the plus side, ECM is easily upgraded in terms of hardware and software and is small enough to be carried by almost any platform.  If the threat changes, we can upgrade the ECM of the entire force with relatively simple software changes.

IR – One of the ways stealth is being countered is through alternate detection methods like IR.  IRST sensors are one of the “hot” technologies, at the moment.  Thus, IR signature suppression offers another form of stealth.  Of course, like radar stealth, this is difficult to achieve and nearly impossible to upgrade over time.  Still, it is well worth the initial effort.  Ships, especially, need more attention paid to IR signature reduction.  The ubiquitous gas turbines that power ships generate immense IR signatures and while they offer obvious operating benefits they also impose survivability disadvantages.  Thought should be given to alternative power sources and to minimizing their IR signatures through careful design.  Measures such as utilizing the washdown systems can provide a degree of IR signature reduction.

Decoys – Simple decoys create stealth, too. Decoys can take the form of chaff, flares, floating radar-reflective targets, towed aerial decoys, towed Nixie anti-torpedo decoys, submarine noisemakers, dummy visual targets (fake tanks or aircraft, for example).  If incoming missiles "see" dozens or hundreds of fake targets (decoys) then the real ones have become stealthy, barring the bad luck to be the one "fake" target that a missile zeroes in on.  Decoys are generally cheap and easily deployed.

Obscurants – Smoke is a great visual obscurant but today there are multi-spectral obscurants – multi-spectral smoke, if you will.  We now have obscurants that can cover the spectral range of visual, near/mid/far infrared, centimeter/millimeter wave, and ultra high frequency. (1)  Laser weapons, laser ranging, laser spotting, and laser imaging can all be disrupted thereby providing “laser stealth” protection.

And so on.

We see, then, that stealth can be provided by means other than the shaping and exotic coating of the individual ship or aircraft. With the foregoing in mind, consider a giant commercial 747 or a commercial cruise ship. They're about as unstealthy as possible - easy detections and kills in a war zone, right? But, they can be made stealthy by other means. For example, if we could disrupt the terminal guidance of incoming missiles (ECM, IR signature suppression, frequency obscurants, etc.) or supply alternate targets in the form of decoys then the 747/cruise ship would be "unseeable" to the missiles and, thus, stealthy even though it contains no inherent stealth characteristics of its own.  Thus, a “stealthy” 747/cruise ship is achieved via other means!

The point is that there are multiple ways to achieve "stealth". We don't have to always go for the most expensive method. In fact, stealth shaping/coating is becoming less and less effective as technology develops multi-frequency radars, back-scatter analysis, multi-node radar networking, IRST, and other technologies designed to defeat stealth shaping.

The alternative methods of enhancing stealth also allow easier upgrades over time. It's very difficult/impossible to "upgrade" the shape of a ship or aircraft but it's easy to change the electronic warfare or decoy capability. We need to rethink where we're putting our "stealth" emphasis. This is not to say we shouldn't build stealth shaped platforms - we should because that's the minimal price of entry onto the modern battlefield - but that we should be emphasizing other approaches as opposed to the ever more expensive stealth shaping/coating path that produces less and less benefit and requires more and more exquisite care in manufacturing and maintenance.

At one point, I thought the Navy might be grasping this concept because they were looking at acquiring more electronic warfare aircraft (EA-18G Growlers) which could have been used to escort other aircraft and bestow stealth.  However, this does not seem to have happened.

Perhaps, in addition to our frantic effort to develop deep penetrating strike and aerial combat UAVs, we should be looking at developing basic, auxiliary electronic warfare UAVs – essentially, flying jamming pods controlled by EA-18G Growlers.  This would greatly extend the capabilities of the Growlers without requiring new, hideously expensive aircraft. 

I’ve mentioned in previous posts that it would be interesting to build a prototype, pure electronic warfare ship with, essentially, unlimited power and unlimited antenna size and numbers and see what it can do to provide area stealth just as Aegis provides area air defense.

We have been myopic about our stealth focus on shaping and coatings and we need to broaden our approach and recognize that there are alternative means of achieving stealth.

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(1)http://www.wood.army.mil/chmdsd/images/pdfs/Winter%202011/Chapman-Reichert.pdf