Smoke and Mirrors (Stealth Paper 1)
First published: 20th June 2011 | Dr. Alexander Clarke and Dr. Arrigo Veligcogna
This work is an examination of the effects of stealth on naval warfare, and whether stealth aircraft represent an insurmountable threat to ships, as is propagated by its supporters.
“Warfare is the art of the deceit”
If what is said above is true, stealth technology is perhaps the ultimate deceit. In the last couple of decades this new component has been added principally to the air threat, and in fact the stealth plane has almost obtained the status of a ‘must have component’ for any nation which feels it should be taken seriously. However, many people’s appreciation of stealth technology differ. In fact the views expressed in the media vary from treating it as some sort of black magic against whom there is no defence, to a condescending appreciation of “it just a passing evolution and soon countermeasures will be widespread”. The opinion of the authors is that as always in appreciating new technology the threat has been both overblown and underestimated, and, as far as naval forces are concerned, has never been appreciated in full. It is thus time, in the light of progressing technology and the debate about air defence of large task forces, to try to assess the realities of the situation.
First of all Stealth is not a sort of cloaking technology imported from a well known science fiction series or Harry Potter. Stealth aircraft do not suddenly and magically disappear. Nor for that matter do stealth ships. Stealth technology is the art of reducing the radar reflection of a given target (air, ground or sea based) to a level that it can be confused with the background reflections. This is rather like submarines that use their differing methods of movement through the sea to reduce their exposure to detection. Land, birds, sometimes even clouds reflect radar emission with a variable level of intensity. With the increase in sensitivity of radar receivers, more and more of those unwanted signals were received and displayed. To reduce the ‘false’ alarms this could generate, computed and special software were incorporated into the radar units to reduce the clutter and filter unwanted reflections; and relieve some of the pressure from the operators. To do all this the Software had to have criteria. So, for example, in earlier systems smaller reflections were completely filtered out, threshold detection levels were introduced. These were based on both the dimension of the radar reflection, the Radar Cross Section (RCS) of a given object and speed.
To both counter and take advantage of these new radar technologies various ideas were considered. The primary effort has been directed in reducing the chances of a successful detection. That has resulted in ‘stealth’, the technology which is designed to reduce the RCS of an object until it is ignored by the radar themselves, and thus probably never even shown to the operator. Usually it works on two principles: dispersion of the radar signal away from the receiver and absorption of the radar signal to reduce the reflection strength. Both approaches use a combination of radar absorbing materials and angled or curved surfaces to accomplish their objective. Older platforms, like the now retired F-117A were using mainly the first principle, creating a distinctive angled look; whilst follow up projects, such as the B-2, F-22, F-35 and X-47 UCAV opted for emphasizing the second with completely different results.
One important fact is that stealth designs tend to emphasize the reduction of frontal RCS with less effective protection on the side. Also RCS is dependent on the position of the radar emitter relative to the target and the range. Thus different radars will have different RCS returns from the same target and with q decrease in range the radar will have a corresponding increase in returns. There is also the operating frequency of the radar to consider in detection range of stealth aircraft and of course when evaluating modern military forces there is the problem of data linkage and combination. For example, one Type 45Daring class might be transmitting but another one, perhaps more, could have their receivers active, thus quantifiably increasing the capability of detection.
Another feature of stealth technology is the fact that, to reduce the likelihood of reflection, ordnance has to be carried internally in order to reduce the number of angles presented to radar signal. The more missiles, bombs and other equipment that are carried externally the less a given plane is really stealthy. Even if the weapons themselves are deemed stealthy their simple presence creates an increase in the RCS.
Summarising; stealth technology is not meant to make the target aircraft magically disappear but to reduce the range and likelihood that radars can positively identify and track it. It also means that other sensors, from those operating in the infrared spectrum to one using magnified images and even the primitive visual sighting are not affected by stealth technology. There are. of course, camouflage measures and technology to reduce the infrared signature, but still the limit of stealth technology means that stealth aircraft almost always operate in the strike role and at night).
Now, when we postulate a hypothetical scenario where a single stealth strike platform is tasked to attack a solo Type 45 destroyer, it will first be necessary to run through the attack mission planning. The first thing that has to be decided is the type of ordnance to be employed by the attacker. There are two possible options; a soft kill using Anti Radiation Missiles (ARM) to simply disable the destroyer radar. This is most likely to be followed up by more conventional aircraft to take out the ‘crippled’ vessel. Or, a hard kill with bombs and anti-ship missiles to sink vessel without the need for a second strike. In all cases both methods are faced with several problems.
ARM missiles have several advantages, they are self-guided and you do not need active targeting. The missiles will guide themselves onto the radar emissions of the target. When they impact the target they usually destroy the antenna and render the radar useless. They are also big, they need a high level launch profile and require the target to have its radar on during the entire flight or at least a sizeable portion of it to detect the signal and guide on it. They usually need their seeker to acquire the radar signal before launch or they can be lofted and launched hoping the target will activate the radar and then guide on it.
While ground based Radars tend to be on continually ship based ones usually are on only when needed. It also requires that the radar signal is in your radar library, it is not classified as friendly or commercial and the seeker is able to process it. Now, modern radars tend to work on multiple wave lengths, switch frequency and usually operate in pulse, as opposed to continuous, mode. They switch on continuous illumination only when they lock onto a target. The ARM missiles are thus a good self-defence weapon but not a suitable one in our mission.
Now, warships have their own stealth procedure and one of them consists of not using their own active radars until there is a compelling need to do so. Instead they rely on their passive ESM system. If the stealth aircraft is really stealth that will never happen except if they expose themselves to the vessel’s radars long enough to be classified as a threat and therefore to be shot down. Whilst the ARM missiles are indeed an important part of a conventional strike package they are less interesting for a stealth attack on a vessel underway.
So we are limited to a hard kill option with bombs or anti-ship missiles. That means a lot more trouble. First of all the attack needs to knowexactly where the target is. With a hard kill strike it is simple, no target = no viable mission.
There are three options for target acquisition a visual search (using the Mk 1 eyeball), external platform (which itself will have to deal a different set of variables) or the aircraft can use internal sensors.
Now, if those launching the attack do not wish to rely on the aforementioned eyeballs, a stealth aircraft will be equipped with a radar, usually highly capable, an ESM sensor array detecting enemy emissions, and some form of IR tracking. ESM and IR are passive sensors, they will not reveal the platform, but they need emissions from the target in order to find it. Modern ships are designed to reduce infrared emission to the smallest possible levels like a stealth plane’s, so the IR detection will occur at short to very short, to impossibly short range depending upon the design of the ship.
The ESM sensor will be affected by the same problems of an ARM seeker. The target will have to switch its radar on. Also ESM gives only the bearing, not the range. Yet considering the fact that ESM ranges are decreased by new technology radars there will be some clues provided should this be the scenario.
That discussion covers the ‘passive’ detection systems, the only real ‘active’ system available other the ‘Mk1’ is radar. Using active radars will give the attacker an exact range, bearing and probably a good identification of the target. But it will also give pretty much all those details to the Type 45 and its ESM; most definitely it will get the bearing, a rough timeline up to attacker’s arrival, and because of the distinctiveness of radar types, a very good idea of what aircraft is looking for it. Also because the aircraft does not know where the Daring is they will have to turn on the radar for a prolonged period of time giving even more clues to the Type 45. Remember that a type 45 is a stealth target itself, larger than the average stealth aircraft, but still stealth. Also radar and ESM ranges are tied to altitude. To increase the ESM range and radar range, the aircraft has to increase its altitude. If the aircraft wants to spot the Type 45 quicker (before it runs out of fuel perhaps), then it will have to get up very high in the sky instead of hugging the waves. In doing that the aircraft will not be presenting its frontal RCS anymore, but instead presenting a different and relatively larger one.
It will also create a window of opportunity for the Daring to engage and shoot it down. Thus, in comes the other factor in any stealth operation; when the aircraft is searching for the ship the ship is searching for it.
Based on published data the effective ESM ranges for the Daring class and a good 5th generation aircraft radar like APG-81 (mounted on F-35C) are almost the same. Usually good modern ship mounted radars can effectively track a stealth plane between 16 and 13 miles. Due to ground clutter the ability of airborne radar to pick and track targets on the surface is slightly degraded. Yet if the stealth planes use an active radar it will be able to pick the Daring between 30 and 50 miles, but it will put the aircraft inside the ESM envelope of the Type 45. This will allow theDaring to plot a fire solution and start a limited engagement; perhaps even launch a missile into the ‘basket’ to see what happens.
That also brings out the fact that to have a good fire solution for a missile the attacker has to have more than single blip on the screen. The radar needs more contact information to determine speed, course and profile. That enlarges the window of opportunity of the ship.
Anti-ship missiles are also big. This means they need (on the vast majority of aircraft) to be carried externally, therefore increasing the RCS of those aircraft – this has been said before, but needs to be remembered. After launch the missiles will be a different situation, most missiles are themselves not stealthy and furthermore they are the exact type of targets that the Type 45 is designed to engage. In fact it has already been done. Therefore the missiles can be argued are a bit of a waste of the platform.
If the aircraft is instead intending to bomb the ship, then another scenario comes into play. Because after all the problems of trying to fix the position of the target, now the aircraft has to pretty much fly straight to it. Broadly speaking bombs came in three categories:
• Laser guided bomb that requires the aircraft to illuminate the target at relatively short range and keep it illuminated until the bomb impact.
• And JDAM type bomb’s using GPS coordinates.
Now the launch pattern of all those bombs is well inside the missile engagement area of the Daring class. With Joint Direct Attack Missiles (JDAM) and LGB the aircraft can avoid gunfire, as it can launch from high altitude, but not the missiles. Furthermore, of course the aircraft will be well inside the active detection range of the Type 45 radar before it is able to launch either type of guided ordnance.
On top of all this, the JDAM’s have another problem. They require exact target coordinates before launch. But the vessel will most likely be manoeuvring at highest speed and as randomly as possible. So, whilst the latest models do have a laser system to guide them against manoeuvring targets, it forces the plane to stay in range and guide the bomb with highly effective missiles coming at it.
The iron bombs will put the stealth plane in the most difficult position. It will be in range for almost every weapon of the ship flying a predictable pattern, well inside detection range and it will have already renounced every stealth advantage. Plus, because a conventional bomb attack will require a massive amount of pilot input the best profile will be a daylight attack thus further reducing stealth advantages.
Thus while stealth aircraft alone are indeed a difficult and dangerous target, the flight profile and the realities of an anti-ship attack will force them to trade off a lot of their own advantages just to acquire the target, especially considering that every effort has been made to reduce signature of a Type 45 destroyer. Plus, if they are not using a long range standoff weapon they will have to close the range so much against a highly capable target that they will operate with the same constraints of non stealth aircraft in the “attack” part of the mission.
The likelihood of the type of attack described above is slim at best. Ships do not operate alone and nor do aircraft. Both systems operate as part of combined arrays of different platforms designed to complement each other. So it is better to take a step away from the original one to one scenario and postulate a combined approach. This time the Type 45 destroyer will be one of the outlying radar pickets of a naval formation and the task of the aggressor will be to remove the threat of the ship to create a corridor to attack the core of the naval force.
What resources can be combined with a stealth strike aircraft to increase its efficiency in this situation? The first scenario has identified two major problems: the need to avoid detection by the Type 45 Radar and the need to get accurate data on the target. It is thus better to concentrate on those two tasks and see how they can be performed while reducing risks to the stealth strike aircraft.
To solve the former, a good idea could be an electronic warfare aircraft like the American designed EA-6Bs Prowler or F-18Gs Growler. Those aircraft are specialized in what is called “suppression of enemy air defences”. This mission involves using firing a lot of ARM missiles against enemy radars while at the same time using active countermeasures to jam the same radars. While the title “electronic countermeasures” seems pretty complex the process is in reality straight-forward. They are just transmitters that generates a lot of signals on the same frequency of the radar and fill the radar screen with a mass of return signals to the point that both the operators and the computers cannot differentiate between real radar returns and false echoes. In practical terms the radar screen become like a TV screen when the signal is not received. Countermeasures and missiles will take care of the Type 45 radar and missiles system and allow the stealth platform to finally turn on its radar without fear and engage the destroyer.
It sounds very effective but these platforms are not stealthy. Once they turn on their own countermeasures the Destroyers will know that an attack is about to happen. Also ARM missiles have a shorter range than the ASTER 30 of the Type 45. Finally the Sampson radar of the Type 45 is designed to see through the enemy jamming. Of course if employed in sufficient numbers the electronic warfare aircraft will possibly overwhelm the Daring, but they will take losses in the process (especially older planes). Such an attack will require considerable resources.
The whole point behind stealth aircraft is that they save resources over conventional aircraft. If we deploy a full group of electronic warfare aircraft to support our stealth strike aircraft where would the difference be? It would be a conventional, resource intensive, strike but not a stealthy one. And electronic warfare aircraft are not cheap.
Maybe it is better to help the stealth to find its target without having to use active sensors; maybe at long range and provide the strike plane will all the data needed for a missile attack. In this case supporting the stealth attacker with a Maritime Patrol Aircraft (MPA) equipped with a powerful surface search radar could be the solution. The patrol aircraft will be tasked to find the Type 45 and then transmit the data to our stealth strike platform. This MPA will use its radar and emit signals.
The biggest advantage of this approach is the possibility of using longer range anti-ship missiles. With no need to close range and use its active sensor, the stealth aircraft will operate outside the engagement envelope of the Type 45. The target acquisition aircraft will use its own dedicated sensors to acquire the Type 45 while the stealth strike aircraft will lurk at the maximum range waiting for the opportunity to launch its missiles.
Having an external aircraft doing the targeting procedure will shield the stealth platform from risks, but also create a whole new set of problems. If the stealth aircraft is now safe, the reconnaissance platform is exposed to the Type 45. Current and projected maritime patrol aircraft are not stealthy. Because they need to carry large radars and stay aloft for long period of time they are also large. They can be defined as juicy targets for missiles. Of course the optimum tactic is to keep the patrol aircraft outside the range of the radar and missiles of the Type 45.
That is easier said than done. Due to the fact that earth is not flat, to increase radar range an aircraft has to be higher than its target. Much higher, but leisurely loitering at high altitude not only increases the range of the MPA, but also the range of the Type 45 radar. ESM has already been mentioned. It is the art to detect enemy radars using their own emissions. Because in such a case the radar signal is travelling only in one direction ESM detection occurs at longer ranges than radar detections so the Type 45 will know what the patrol aircraft is doing long before the radar on the aircraft will detect the ship. Comparing the ranges of current radars, it shows that there is a shadowy zone where a little luck and creative manoeuvring can help the patrol aircraft to find its contact and then transmit the data to the stealth strike aircraft for the attack.
A stealth strike with external target acquisition thus appears, on the surface, the most attractive option; at least the one that deserves to be considered in more depth. The strike platform will still benefit from stealth technology and this time, operating as part of a full strike package it will be tasked only for the attack itself. The second platform, the MPA will locate, identify and track the target and relay the data to the strike platform. If the MPA can send the target data to the strike aircraft in time, it is not relevant if it survives.
The cat and mouse game is now between a Type 45 and the MPA. Until the aircraft is able to get the data the stealth strike platform is useless. In this scenario the Type 45 will have her first bearing on the opponent radar (using ESM technology) well before the reconnaisance aircraft will be able to locate it through its surface search radar. While the ESM will provide only a bearing the destroyer captain can use the embarked Merlin helicopter as an additional ESM receiver. With two different bearings and knowing the exact distance between the two receivers a basic trigonometric skill will allow the ship’s crew to triangulate the position of the search aircraft and if necessary close the range to the point its Aster 30 SAM (varying between 50 and 70 miles according to the sources) can be used. All without turning the radar on. It is also worth observing that the maximum published envelope (70 miles) is only marginally inferior to the stated range at which a current surface search radar like the Russian designed Uspekh could localize the Daring (103 nautical miles). Thus the patrol plane will have a very short window of opportunity to relay its finding to the stealth aircraft before being shot down or having to concentrate on surviving.
The data necessary for an effective missile launch are the same as the earlier scenario’s, forcing the MPA to track the Type 45 continually to have bearing, range, course and speed. Even if the Aster missiles is launched at extreme range with sub-optimal kill probability, the need to evade the missiles will force the aircraft to lose its tracking. Incomplete data will greatly reduce the accuracy of the follow on attack.
While this is a hypothetical situation several real life examples of this procedure indeed exist. During the Falkland war the effectiveness of the Argentinean Exocet attacks was dependent on the ability of their MPA (in this case old Lockheed PV2H Neptune) to track their targets outside the air defence area of the British Task Force. If the effort was unsuccessful the entire strike operation had to be called off.
The same problems were experienced by the Iranians during their alleged missile attack against US surface vessels in 1988. In such a case the aggressive action of air defence ships engaging the Iranian tracking planes at maximum range while it did not cause any confirmed losses on these platform reduced the effectiveness of the subsequent missile launches. In one of the engagements, the USS Gary, an US Navy frigate, used the procedure described above to suddenly bring an Iranian patrol helicopter in range and fire. The helicopter was seen on the radar screen (the missiles embarked required active radar guidance from the ship at the time) losing altitude very quickly and then disappearing on an island to avoid the American missile.
If the stealth strike aircraft succeed in anyway in launching its missiles the problem changes completely. The threat in this case is not anymore the stealth strike aircraft itself but the missile. Anti-ship missiles are not stealthy, even if some stealth missiles are rumoured to be on the design boards, and even if its RCS is very small the speed of the contact will make sure the software of the radar will pick it up and identify it. The Type 45 is indeed designed to combat these threats. The Aster 30 and 15 missiles have been designed with anti-ship missiles in mind. It will no longer be a battle between stealth technology and the Type 45, but between the Type 45 and the threats it has been designed to fight and destroy.
In the end, the combined scenario where the stealth platform is used only for the final “kill” underscores the role of the stealth platform. The target is no more the stealth aircraft, that becomes just a marginal player, but the target acquisition aircraft and the anti-ship missiles themselves. Threats that are fully inside the Type 45’s engagement envelope.
In this report several hypothetical situations have been presented to the readers. They showcase real capabilities in a way the authors felt would make it most understandable to those without a vast amount of previous knowledge. The questions of this report are not hypothetical but real. What is stealth? What purpose does stealth serve?
It is important to be able to grasp the concept behind modern technology in order to avoid being overwhelmed by it and its prophets. Too often in the past a technical solution has been believed to be also a strategic, operational or tactical solution. History has demonstrated that it is not.
The analogy of the two men in dark alley armed with shotguns and torches comes to mind when describing stealth in modern warfare, although it simplifies the problem of course to a degree – it is still appropriate. Neither man wants to use their torch and give away their position; under such circumstances they must approach until they can distinguish a shadow in the dark, and hope that the shadow is the target. If there is more than one man on each side in the alley it will be a truly deadly game. One man might use the torch illuminating the alley for the one with the shotgun. But this in turn exposes him to the opposition so any move has to both cover them and allow an offensive action; the more illuminators and the more shotguns involved the more complicated it gets.
There is also another inherent danger in believing technology is the ultimate solution. Counter technologies are constantly developing. Technology advantages are fleeting and often expensive. Too often they are effective only for one or two uses, then other nations want a counter and offer the necessary cash and it is developed. Phased array and multi frequency radars have been developed to detect stealth planes at longer ranges. Techniques to maximise chances of detection have been refined. Some would in fact say that technology is just a chimera.
Of course it is not. It is just less a game changer that people want to believe. Even when counters are developed technologies are still useful, but they then become part of a multilayered approach. From ancient times, the right answer to military problems has been combined arms. Combining different platforms to exploit strength and compensate weaknesses is the key of being successful in warfare – it always has been. Relying on miracle weapons is never really plausible. There is also another element in that equation: training. Everything else being equal training will be the deciding outcome, not technology. Training raises morale. Morale can win wars.
In the end stealth aircraft are important, no one denies that, but they are also part of a complete and combined arms approach. In the recent times stealth capability has been trumpeted as the final solution to every military problem. This stems more from ignorance than competence. It is also worth noting that stealth technology has been developed not to attack small moving targets, but to destroy large fixed installations deep behind enemy lines. Subsequently it has been expanded to improve chances in air-to-air engagement; but also stealth is a defensive measure and to achieve success offensive measures have to be taken thus reducing the effectiveness of the stealth. Also despite the claims to the contrary stealth is not revolutionary, it is just an evolution of already known concepts – a modern equivalent of the Trojan Horse. It is just the latest section in a race which is as old as war; the race between hiding and seeking, where each side gains fleeting advantages – but ultimately usually ties.
 In fact the biggest problem for the 1982 Falklands Task Force from a radar perspective was that their units were focused on operating in the middle of the North Atlantic…not close to shore as they had to with the amphibious task group where land clutter reduced their ability to detect aircraft.
 It is worth noting at this point that flat surfaces at 90 degree from the signal direction and right angles generate far more reflection than curved surfaces or smaller angles. In fact even platforms not classified as stealthy but presenting a rounder and sleeker appearance, were exploiting (often unknowingly) stealth principles. As an example, the relatively older American B1-B bomber due to its design presented a much smaller RCS than its contemporary soviet counterpart, the Tu-22M.
Loitering in plain daylight until the pilot gets a glimpse of the target using Mk I sensors (or eyeballs as everyone else calls them) is not a real option in a stealth aircraft as a) the vessel could be pretty much anywhere in a wide area, and b) if the pilot gets bored and just decides to risk it and turn’s on the aircraft’s radar, then the chances are the plane has already lost.
 Like the Argentineans were doing during the Falkland war for their Exocet attacks; but that will require other platforms and this will be investigated in the next chapter.
 Furthermore there is also the possibility that an optically tracked 76mm gun shot down a cruise missile in 1988. So shooting them down is not something that is new.
6.0 Recommended Reading
Bond, L., & Carlson, C. (2003). Harpoon 4.1. Sassamansville: Clash of Arms Games.
Clapp, M. (2010, February 19). It’s the bitter truth: We couldn’t send a task force to the Falklands today. Retrieved February 19, 2010, from Mail Online: http://www.dailymail.co.uk/debate/article-1252149/Its-bitter-truth-We-send-task-force-Falklands-today.html#ixzz0fyB0Vv7o
Clapp, M., & Southby-Tailyour, E. (1997). Amphibious Assault Falklands, The Battle of San Carlos Water. London: Orion Books.
Clarke, A. (2009, November 01). In Defence of the General Purpose Destroyer. Warship International .
Grinning, P. (2009). The Outer Air Battle. Harpoon Naval Review , pp. 34-39.
Hill, J. R. (1988). Air Defence at Sea. Shepperton: Ian Allan Ltd.
Smith, J. T. (1994). Rolling Thunder, The Strategic Bombing Campaign North Vietnam 1965-68. Walton on Thames: Air Research Publications.
SPG Media Limited. (2009). Type 45 Daring Class Anti-Air Warfare Destroyers, United Kingdom. Retrieved May 18, 2009, from Naval Technology: http://www.naval-technology.com/projects/horizon/
Woods, N. (Ed.). (1996). Explaining International Relations Since 1945. Oxford: Oxford University Press.
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