The myth of the precision bombing
Posted by picard578 on January 19, 2013
Many people believe that modern guided (dubbed “smart”) weapons allow for pinpoint precision from very large distance, such as allowing fast high-flying aircraft to carry out Close Air Support, or to engage targets in urban environments.
In NATO missions in Libya, carried out to “support” anti-Gadaffi rebels, have killed or wounded multiple civilians and rebel troops. It is nothing new – as noted in the article, up to 25 – 80 % of casualties in wars have been caused by friendly fire (this also shows why BVR combat is unlikely to become prevalent form of air combat, as potential for misidentification is far greater). Visual ID has time and again proven itself as only somewhat reliable type of identifying targets, and even it is not perfect. As such, fast jets are completely incapable of identifying targets. WW2 Stuka pilot, Colonel Hans Rudel, has stated that “high speeds are a poison for finding tanks” – and that was in flat Ukraine, flying an aircraft far slower than modern jets. Army Sgt. First Class Frank Antenori has stated same thing.
In fact, due to lack of A-10s, F-15Es have on multiple occasions found themselves using their guns to strafe targets in Afghanistan. While they were mostly successfull, end result was longer time required and less successfull mission than what would have been with A-10s. A-10 also has very long loiter time, which means that – unlike “multirole” jets – it can be on station hour after hour, providing permanent presence and near-immediate answer to any CAS request.
Furthermore, units are equipped with limited number of radios, making identification difficult. While low-flying UAV’s can be used to identify targets, such usage is dependant on lack of any serious air defenses as well as presence of secure uplinks.
But even when targets are identified, precision weapons’ performance is nothing stellar – unless killing civilians is considered, where casualties have increased from WW2-standard of 9 tons of bombs per civilian killed to 200 civillians per one bomb, and drones’ effectiveness of 6 civillians per attack. This shows that, for precision weapons to be used correctly, either aircraft must be slow enough and low enough for pilot to use binoculars for identification, or identification must be done by troops on the ground.
Precision weapons have to have their points of impact calculated. Result was that, even with fast jets in the air, it took anywhere from 26 minutes to several hours for munitions to be finally delivered.
Guided munitions are also only effective against fixed targets. But against mobile targets, low-speed low-altitude attacks with cannon or unguided munitions are required to achieve any kind of effect, rendering DAS (Distant Air Support) ineffective. As such, laser designators have to be complemented with smoke grenades and marker baloons. JDAMs are not terminally guided, and as such are very likely to go astray.
While satellite surveillance is avaliable, it is very-long-distance, and as result it does not offer good target-recognition capabilities – to satellites and high-flying aircraft, cardboard decoys are indiscernible from actual targets, and it takes 18 hours for strike to arrive. UAV surveillance, on the other hand, is insufficient, whereas UCAVs can only attack fixed targets.
And problem sometimes isn’t too few data – it is too much data displayed to the pilot, overloading him and distracting him from the mission, as well as increasing time required for “observation” in OODA loop.
There are problems with munitions themselves too – further away bomb is dropped from, greater error becomes. On release, bombs often bump into each other – and sometimes aircraft too – causing fins to get bended and thus reducing accuracy. This is problem that only increases with increasing speeds, due to stronger turbulences. GPS weapons’ guidance systems also often malfunction, with bombs hitting miles off the target. A laser-guided bomb, meanwhile, can be thrown off course by a laser beam guding it being disturbed by a debris or simply by smoke, dust, clouds or highly humid environment, thus causing bomb to go ballistic.
During Operation Desert Storm, at most 60% of bombs have achieved hits on targets, and many misses were off by hundreds of meters. In fact, success rate could have been as low as 41%. While officials have said that strategic targets will be destroyed in 10 days, it took two weeks to destroy nuclear weapons factories – and all other targets have only been damaged, not destroyed. Out of 15 SAM batteries attacked by low-flying F-117s in Baghdad at first night, 13 continued to operate. All Coalition aircraft hit only 21 of 37 “crucial” targets. It also took between 4 and 10 laser-guided bombs to destroy targets such as bridges – similar to success rate of dive bombers against aircraft carriers during Pacific war.
In Kosovo War, only 58 successfull strikes have been made by USAF out of 750 attacks, destroying 14 tanks, 18 APCs and 20 artillery pieces. Out of 80 SAM batteries, 3 were destroyed. That can be compared to USAF claims of 120 tanks, 220 APCs and 450 artillery pieces destroyed. Chinese Embassy was also bombed, which was a repetition of President Reagan’s raid on Libya, when French embassy was bombed by “precision” weapons. Civilian casualties were one for every 10 tons of bombs, very close to WW2 rates. In Vietnam, casualties were one for every 12,5 tons of bombs. UK’s bombing accuracy with smart bombs was 40%.
In Afganistan, 2001, B-52 dropped precision ordnance around 100 meters from US Special Forces team, killing three US soldiers and five Afghan government soldiers. Other than several such incidents, however, war has been a positive example of USAF integrating more with the Army. Still, errors cannot be done away with, and problem gets worse faster the jet flies.
During 2003 invasion, US “precision” weapons have managed to miss Iraq entirely, falling into Turkey and Iran (at least US heavy bombers in WW2 never missed the country, though they did occasionally miss the city in entirety). Civilian objects, including hospitals, were consistently hit, and 2003 precision bombing has been more deadly than 1991 bombing which was done mostly by “dumb” bombs – killing 1350 civilians per 10 000 tons of bombs, as opposed to 400 civilians per 10 000 tons. This can in part be attributed to pilots dropping bombs from greater altitude due to the belief that part of targeting can be taken over by the projectile itself. Ballistic missiles did not fare much better, with only one-third hitting targets, one-third failling to detonate and one-third missing alltogether. It also happened on Balkans, when NATO bomb intended for Serbia fell in Sofia, Bulgaria. Accuracy of bombs against radar sites was 32%.
What is important to realize is that many of described attacks have taken place at low altitude – inly in Serbia did bombardment come, as a rule, from high altitude due to altitude limits placed, which means that it could be considered most indicative for high-altitude bombardment success rate. But even when bomb or missile does hit the target, debris from 1-ton bomb can cause casualties hundreds of meters from the impact point; radius for a 2-ton bomb can extend to a thousand meters. In fact, while 450-kg GPS bomb has CEP of 12 meters, blast damage extends to 30 meters and fragmentation damage extends to 900 meters. Area of effect is calculated by cube root of yield, so 227 kg weapon would still cause blast damage to 24 meters and fragmentation damage to 716 meters. As such, precision munitions are completely unsuited for CAS roles as well as operations in urban areas or areas where there might be civilians present. Furthermore, due to the expensive guidance systems, trend is for precision munitions to have higher yield than “dumb” counterparts, increasing the problem.
UCAVs used for assassinating terrorist leaders are especially problematic. Of 700 people killed by UCAVs in Pakistan, only 14 have been Taliban, which is mostly connected to unreliable intelligence and careless approach.
While some say that low-and-slow-flying CAS aircraft are vulnerable to being shot down, aircraft is just as safe from SAMs and MANPADS below 30 meters as it is above 3 000 meters. It is in-between these two values that trouble occurs. While average infantry division has large number of automatic weapons, most of these are small-calibre and thus only suited for engaging typical fighters (F-15, F-35) and not armored ground attack aircraft such as A-10 or Su-25 which can survive even direct hits by full-sized SAMs in good portion of cases – 50% in case of the A-10. In reality, real threat for CAS aircraft are enemy fighter aircraft, although the mere fact that CAS aircraft fly very low might make job difficult for radar-guided missiles. On the other hand, large aircraft such as AC-130 Spectre are vulnerable, can only be used at night. and have more limited capability for providing effective CAS. In Gulf War, only the tough A-10 and very fast Tornado operated at low altitudes due to persistent threat from optically-aimed AAA and IR MANPADS. Unlike other aircraft, both these types proved survivable in the environment.
Since precision weapons are tested in deserts, in fair weather (without anything that might impede bombs) and against static targets, official claims about their actual precision can be disregarded – they are equally faulty and based on equally flawed assumptions as pre-Vietnam claims of 90% accuracy for BVR missiles, which has turned out to be around 8% in combat.
Precision bombing myth is also nothing new. Norden sight for B-17 was claimed to be able to “put bomb into a pickle-barrell from 20.000 feet”. In the end, entire city blocks were levelled when bombers attacked specific targets, with bombs falling hundreds of meters off the target.
Conclusion? While guided munitions can be and are helpful, they are not magic, and aircraft still have to go very low and very slow – until pilots can see target through the canopy – in order to reliably hit tactical targets. Old-fashioned cannons are still most precise weapons in arsenal, when used well; and while precision munitions certainly can be useful, their main usefulness is not so much in increasing range from which attacks are made as in allowing pilot to spend least time possible “on target” and concentrate on evading enemy AA fire.