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Posts Tagged ‘UCAV’

On drones

Posted by picard578 on May 25, 2013

Some say that UAVs can replace tactical aircraft, and that, being cheaper, can be produced in greater numbers. But UAVs have greater logistical burden when compared to even relatively complex manned fighter, as UAV support crews need to eat, and maintenance isn’t simple either. More C-130s are required, more parts and technicians are also required for both UAV and support mechanisms. Neither can UAVs do ground attack missions, and combat-capable UAVs aren’t going to be cheap even when counting only production costs. And while I did write an article about (in)ability of UAVs to replace manned fighters, I hope for this article to be more detailed and adress some issues I have not touched in my previous article.

UAVs were first used in Spanish-American war in 1898 when journalist William Eddy took hundreds of photographs from camera suspended under a kite. While not strictly “UAV”, in third century BC Chinese used kites to help with triangulating distance required for tunnel dug under the walls. First heavier than air unmanned aircraft flew in 1896, over Potomac river. In World War II US military attempted to develop a radio-controlled bomber, codename Aphrodite; none of prototypes were successful and project was scrapped. First successful military use of UAVs was in Vietnam, with Ryan 147 Lightning Bug flying 3.435 reconnaissance sorties during Vietnam war. In 1972, modified Lightning Bug was used to launch a missile against simulated SAM. In 1982, Israel successfuly used UAVs in reconnaissance role in Lebanon, and US Navy acquired UAVs from Israel for use in Desert Storm. But are modern UAVs useful? I’m going to take a look at following missions: air superiority, ground attack and reconnaissance.

Complet required for two unarmed Shadow 200 UAVs costs 36 million USD, and UAVs themselves cost 275.000 USD. Single unarmed Predator costs 17 million USD flyaway, and 3.200 USD per hour to operate, without counting control systems. Reaper costs 17 million USD flyaway and 3.600 USD per hour; group of 4 plus control equipment costs 129 million USD. Global Whale (offical name Global Hawk) reconnaissance UAV costs 141 million USD plus 17 million USD per year; while SR-71 costs 261 million USD, having in mind sortie rate issues described later, it is entirely possible that SR-71 may provide more sorties per 1 billion USD spent on aircraft acquisition. Single X-45A, a new US UCAV, is estimated to cost 25 million USD flyaway at empty weight of 3.630 kg. As final version, X-45C, weights 19.000 kg, flyaway cost will likely be 131 million USD. Carrier capable X-47B is expected to weight 6.350 kg empty; flyaway cost will likely be around 100 million USD. Thus UCAVs will cost 25-130 million USD and weight 3,6 to 19 tons, resulting in costs of 6.800 to 15.700 USD per kg; compare to 16-18 million USD and 5,7 to 11,32 tons for well-designed manned fighters, resulting in costs of 1.400 to 3.200 USD per kg, and 30 million USD for F-16A, resulting in cost of 4.240 USD per kg. As X-45A is unlikely to be used for combat, especially for air-to-air, operational UCAVs will be as heavy or heavier, and far costlier than my proposed manned fighters. European UCAV project, nEUROn, despite only being capable of ground attack missions, weights 4.900 kg empty and costs 32,5 million USD, a cost of 6.633 USD per kg. Air superiority UCAVs will cost even more than given costs because of requirement for pulling high g maneuvers, which will put strain on airframe, and especially on fragile electronic components – it is likely that cost of typical air superiority UCAV – if these ever appear – will be 30 to 200 million USD flyaway. None of these costs take into account cost of control systems, such as control unit and communications hardware.

UAVs are notoriously unreliable. While UCAV replacing 4th generation aircraft will cost as much as – or more than – fighter it is replacing, UAVs loss rate is higher than that of manned fighter – even if UCAVs cost turns out far less than that of modern fighter aircraft, in the long run it will be far more, and will support effectively smaller force due to high maintenance requirements and inability to build up numbers caused by huge loss rate. Class A mishap (loss of aircraft) rate per 100.000 hours was 4,1 for F-16, 6,8 for U2, 20 for Predator, 88 for Global Hawk and 191 for Shadow. 2005 Congressional Research Service report indicates that UAV is 100 times more likely to succumb to failure than manned aircraft; considering US DoD history of misreportation, it is possible that figures cited underestimate UAV loss rate (CRS report also cites F-22 loss rate as being 6 per 100.000 hours).

Claim is that UAVs do not require a pilot, and that this reduces costs even more. This is incorrect: UAVs require pilots, except these are not in aircraft itself. Further, while 4 JAS-39 require 4 pilots and 40 maintenance personnell, each Reaper 4-drone CAP requires at least 171 personnell, including 13 pilots. This does not account for other support personnell: drones operating in Pakistan are dependant on US intelligence community as well as tens of thousands of troops stationed in Afghanistan; without these troops, they would not have bases to operate from. And in serious air war, people are just as much in danger on the ground as in the air, if not more so; result is that drones put more people at risk, not less. Even in permissive airspace, they are always used alongside ground forces, while in any kind of defended airspace they require manned fighter escort to operate.

Reaper can only withstand 2 g maneuvers, and high angle maneuvers can lead to connection loss, resulting in a crash. Maximum payload is 1/5 of A-10s and it has nothing comparable to massive GAU-8 cannon. It can also loiter between 18 and 40 hours, depending on payload. Read the rest of this entry »

Posted in weapons | Tagged: , , , , , | 4 Comments »

Why UAVs cannot replace fighter aircraft

Posted by picard578 on January 26, 2013

Despite all technocrate’s dreams, aerial combat between peer opponents was always visual-ranged. Reasons for that vary; main reasons are inadvisability of using active sensors, low probability of kill for BVR missiles, and IFF problems. All of these problems are far greater against numerically and technologically comparable (or simply numerically superior) opponent than against numerically and technologically inferior opponent. Thus, WVR combat is likely to remain standard for aerial warfare, along with its large accent placed on OODA loop.

OODA (Observation-Orientation-Decision-Action) loop is fundimental principle of air combat. Fighter pilot first observes situation; after that, he orients based on previously-avaliable and acquired information (nationality of opponent, cultural considerations likely to affect opponent’s actions in current situation, etc.), then decides on further course of action and acts based on that decision. In the next loop, he observes opponent’s reaction to his own action so far as well as new situation, with rest of loop proceeding as in first one, though “orientation” part takes far less importance unless new information comes into play. In any case, breaking opponent’s OODA loop or going through it faster than opponent is prerequisite for victory. Opponent’s OODA loop can be broken by denying him vital information (done through usage of passive sensors, small visual and IR signature of one’s own aircraft, employment of various forms of jamming and environment-based interference), as well as by going through the loop faster than him – be it through faster observation/orientation/decision or executing action faster than opponent, which requires maneuverable aircraft capable of quick transients from one maneuver to another.

OODA loop of UAV operator is always imperfect, and worse than that of fighter pilot. Major problem is a delay from two to five seconds between UAV recording image and image being seen by UAV operator. Total delay between drone’s sesors recording opponent’s action and drone finally reacting to it – delay between „observe“ and „act“ part of the loop – can therefore reach ten seconds. Due to this delay, unmanned vehicles will be completely incapable of being inside human-piloted fighter’s OODA loop, which is a prerequisite for victory in a dogfight. But there are even more shortcomings than that.

In particular, each part of OODA loop is in itself imperfect. Observation made solely with information from mechanical sensors is never perfect as we have yet to design sensor as good as human eye. Imperfect observation means that imperfection continues to snowball through latter three parts, ending in action with some measure of disconnection from reality – and that can continue through multiple loops.


While drones are much smaller and cheaper than manned fighters, it is only result of their mission. If modern drones are faced with SAMs, MANPADS or enemy fighters, engagement is a foregone conclusion – and one not in drone’s favor. Drone operators cannot detect threats to their aircraft, and if drone was to be designed to be as capable and survivable as manned jet fighter, it would be just as large and costly, if not more, due to the need for advanced computers and communication systems. Even current, relatively simple, drones have much higher operating costs than manned aircraft, and are as much as ten times as prone to crashing – and both shortcomings can only worsen with increased size and complexity required for aerial combat.


Gigantic data transfers required to operate drones can easily lead to communication systems being overburdened – single Global Hawk drone uses as much bandwidth as did all US forces in the invasion of Afghanistan. Bandwidth is also a hidden cost of UCAV – while UCAV itself may be cheap, it requires very expensive (on order of hundreds of millions USD) equipment for data transfers, and even with modern UCAVs performing relatively simple tasks, data transfers can take up lion’s share of 250-million-USD satellite’s bandwidth. As such, entire package (UCAV and equipment required to operate it, which is actually part of UCAV despite not being in the airframe) can rival or exceed cost of manned fighter, with latter being a certainity in any UCAV capable of air-to-air combat.

Further, increased bandwidth automatically means increased vulnerability to jamming and other forms of electronic countermeasures. Main way datalinks defend against jamming is by reducing data transfer speed in exchange for increased reliability; that, however, may not be an option for data-hungry UCAV. As such, UCAV’s will be incapable of executing missions in heavily jammed environment, unlike manned aircraft, especially since it is far easier to build very powerful spread-spectrum jammer than to create jam-resistant uplinks.

Drones are also vulnerable to computer viruses, which could take control of a drone and order it to do anything by simulating incoming traffic from its operator.


It is also important to realize that UCAV capable of matching or exceeding the aerodynamic performance, load carrying capability and combat radius of manned fighter would be exactly as large and heavy as fighter in question. This would mean similar production cost to manned fighter (not counting control and data transfer systems), but at far higher maintenance costs, as much as several times higher, which would make it impractical to replace manned fighters with UCAVs on one-for-one basis. Further, having UCAV brings no operating cost savings, since it actually requires more operating and maintenance personnell than manned fighter due to the greater complexity.

As a result of everything above, replacing a manned fighter would require a fully-functional AI with almost identical cogniscive capabilities to a human brain – a feat that is, at this point, completely beyond both our knowledge of human brain, as well as beyond our hardware capabilities, and will remain so for some time – interestingly, contrary to MIC technology advocates, computer science experts have a complete disagreement on wether true AI can be achieved by the 2040; in any case, past trends do not give any reasons for optimism in that regard. Even when that is achieved, such complex programs would present serious reliability, maintainability and implementation challenges, possibly to the point of making an AI UCAV basically unflyable.

Drones will, however, remain useful in intelligence gathering, a role they have been used in since Vietnam, as drone being shot down does not carry the risk of operator being captured for questioning, and is much more politically acceptable. While these advantages also exist in regards to manned combat aircraft, disadvantages are simply too large.

Posted in Uncategorized | Tagged: , , , , , | 11 Comments »

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