Chapter 4

While it is possible to draw upon thousands of years of the history of warfare for both land and sea, most of the development of air warfare has taken place in this century. It is therefore much more difficult to take the historical perspective as to which techical developments have been of greatest significance, but there is no doubt that the aircraft itself has changed the whole nature of warfare.

The use of balloons as artillery observation posts was well tried by the end of the 19th Century. They provided convenient 'high ground' where nature had omitted to fill the military need. Even more than the naval sail ships, they were at the mercy of the wind and were normally tethered. It was the technical development which allowed man to choose his path through the air which was crucial. The combination of lighter-than-air vehicle with internal combustion engine and air propeller was the obvious route. Indeed the military followed this development line with some enthusiasm before World War One. Looking for more power and greater range increased the engine and fuel weight, which in turn required ever larger displacements to support the weight. The potential of the airship was limited by the laws of physics from the outset. Nevertheless, their range and payload in the early days of air warfare did contribute to future strategic thinking. The raids by German Zeppelins in the early part of the war showed that air power could take the war right back to the opponent's homeland, which had previously been thouht of as a safe refuge.

The longer term development of air power was to be through the heavier-than-air route. Otto Lilienthal developed the glider in the last quarter of the 19th Century, and from the experience of over 2000 flights was able to point the way towards the design of powered aircraft. In 1896 an unmanned steam-driven aircraft made a successful flight, and on 17 December 1903 the Wright brothers demonstrated the first heavier-than-air powered flying machine controlled by a pilot (1).

The military potential of machines which have freedom of movement above the surface of the earth seems self evident now. In the United States, the War Department was uninterested for the next 3 years. In Britain, establishment interest was equally dismissive of the potential of aircraft. A War Office report of 1904 recommended work only on balloons and airships. Two events, one civil and one military, changed the general appreciation of the potential of the implications of the new technology of manned aircraft. On 25 July 1909, Bleriot flew the English Channel and gained worldwide publicity. The strategic security that Great Britain had enjoyed for centuries through its navy had been put in jeopardy by a fabric and piano wire flying machine. Then in 1911, the Italians used their primitive aircraft in the war in Libya.

The use of aircraft for reconnaissance was rapidly developed, and great publicity resulted from the first dropping of bombs from over the side of the aircraft.(2) In Britain, the Prime Minister, Asquith, was concerned by the great increase in military aircraft activity overseas, and initiated a study into the implications which brought about the formation of the Royal Flying Corps in 1912. The lessons were absorbed at different rates by nations, and surprisingly the United States was amongst the slowest to invest in this new technology (3).

Britain had 63 aircraft in August 1914, yet by 1918 was producing 2000 machines every month. Military technological development accelerates rapidly under the pressure of national survival. Certainly, developments in mass production techniques were a crucial element in many areas of wartime production in 1914-1918. There were considerable problems in developing both roles and equipment at a time of total war, and meeting an enormous production requirement. Many of the modern roles of air power had been demonstrated before the war started. Torpedoes had been dropped from aircraft in 1911, and they were tested for anti-submarine operations the following year. Even deck operations from a cruiser had been tested. At the start of what was initially a land war, the role of the few aircraft involved was seen as reconnaissance, although there were still Generals who felt this was better left to the cavalry. The fighter and the bomber were both important developments during the war. The key to the fighter was the requirement for forward facing machine guns, while for the bomber is was accurate navigation and bombsights.

In the same way that the components for the tank were available some time before the necessary imagination to assemble them, the fighter had to wait for the interruptor mechanism that coupled the machine gun to the aircraft. Once air-to-air combat became possible, the priority was for greater power and speed, and more firepower. The same qualities were needed for the bombers, looking for range and payload. The raids on London by German Gothas in mid 1917 were to shape strategic thinking for the inter-war period. The power to bring a war to the home population through strategic bombing was a new element in warfare. The effect on civilian morale of a single raid by 21 aircraft on 7 July 1917, dropping some 3 tons of bombs on London and killing 60 people, was extreme. The effect on strategic thinking, and hence on priorities for development of airpower over the next 20 years was profound. Strategists such as Douhet were already 'proving' that the bomber was the ultimate future weapon, and that wars could be won without the intervention of ground forces.(4).

In fact there were many examples of the way in which air power could contribute to victory which were far more significant than the relatively small scale strategic raids. When the aircraft used were fully integrated with the ground forces' plans, through the co-ordinated use of reconnaissance, fire support, air defence and logistic resupply, great results could be achieved by relatively weak forces. The Palestine campaign at the end of World War 1 was a prime example of such a use of the new capabilities which airpower offered (5). In that war, it appeared that proper exploitation of the technology was best achieved when far away from the military leadership in Europe.

Military airpower went into a severe decline in the 1920's. It was expensive in capital equipment, and required highly trained aircrew. It also lacked the strong lobby which ground and naval forces enjoyed in most countries. Indeed the establishment of a separate military arm to run air warfare was by no means universally accepted. At the end of the war, the RAF in Britain had some 22,647 aircraft, and could produce new machines at the rate of 3500 per month. The war-winning technology was as much that of mass production, as that of any special weapon system. While the strategists could call for greater priority to aircraft development, nations were unwilling to divert resources to military machinery after the war to end all wars.

Technology for new military aircraft came not from the carefully researched concepts for future wars, but from more ordinary considerations. The development of worldwide civil air travel forced the pace on aircraft design for long range, and new navigation systems. The search for higher speeds in air races, such as the Schneider trophy races of 1927-31, improved engine and airframe performances. It was the mid 30's before the all metal monoplane became the norm. Mitchell in the USA tried to demonstrate the vulnerability of naval vessels to properly used air-delivered weapons. However, the US Navy did begin to appreciate the importance of having their own air arm, and developing carrier born forces. The future of airships seemed to come to an end in this era following the R-101 and Hindenburg disasters. By the start of World War 2, it appeared that twenty years of possible technical advance had been lost for miltary aircraft. The advances had come from civil aircraft design, improved engines, better mass- production techniques, and a better understanding of aerodynmics. Communications through radio were by now universal.

In one area of technology advance, military research was beginning to come to fruition. In 1935, Watson-Watt in England demonstrated the first successful aircraft detection system based on radar. Hertz had shown in 1887, that radio waves could be reflected from solid objects. It had taken nearly 50 years for this amusing scientific novelty, to be translated in great secrecy to a crucial military breakthrough. Even in this case the military application stemmed from a Post Office report of 1932 about aircraft interfering with radio signals (6). Other nations were also working on parallel developments, but possession by Britain gave a significant advantage in the air defence of the country in the early stages of the war. Once the principle was demonstrated, radar was developed in many different ways. Higher frequencies gave greater resolution, higher power to get longer range, smaller equipment to fit in aircraft to spot ships and submarines on the surface. Airborne radar could be used for navigation, which improved bombing accuracy, and allowed bombing in all weathers and at night.

The development of radar spawned a series of countermeasures in the form of jamming and dipole metallic strips (chaff) to prevent the target from being seen. Radar was a technical surprise of an importance comparable to the submarine, or the tank. It permitted the aircraft to be used as an effective air defence weapon, preventing the bomber from getting to its target. The application of science to produce military radar parallels the development of atomic weapons. The physical principle on which it was based was well understood, and freely available in textbooks. It took the insight to see the military application, coupled with the stimulus of a threat - in this case the strategic bomber threat - to produce a research project which could demonstrate its practicality.

World War 2 provided the impetus for many technical improvements to military aircraft. The bomber needed to be able to navigate accurately to the target without visual reference, and without giving its position away to enemy air defences. Radio navigation aids such as Loran provided this capability. Bomb aiming needed to be improved through new bombsights, which coupled the benefits of improved navigation, radar and ballistic calculations to reduce the errors. Bombs became bigger as bombers grew larger and heavier to carry all the equipment and self-defensive weapons. The bigger aircraft could no longer operate from grass fields, but needed concrete runways. Thus the technology which brought more effective bombers into being, also brought a new dependence on fixed runways, which in turn became attractive targets for attack.

Fighters fitted with their own air interception radar became available from the end of 1940 onwards, and could operate effectively by night. The fighter's weapon remained the gun, but range and firepower increased as engine performance improved. Speed, rate of climb and maximum altitude all benefited from the spur which combat gave to technical progress. For air defence,the coupling of radar and anti-aircraft gun systems provided a potent combination. The problems of identification of friendly aircraft increased as air defence weapons became more capable. Again radar technology could provide an answer.

At sea, air power could be used either from land bases or from increasing numbers of aircraft carriers. The importance of the carrier to naval forces was considered in Chapter 2. Aircraft allowed firepower to be delivered at ranges far beyond earlier experience of navies. The submarine remained a difficult target, and highlighted the importance of intelligence. Indeed the work of those engaged on code breaking was every bit as important as the new detection systems which were becoming available in the war against submarines. (7)

Towards the end of the war, there were three technological developments which were profoundly to affect air power thinking in the post war era: the missile, the atomic bomb and the jet engine. Germany had developed two unmanned long range bombers. The V-1 was a small aircraft launched by a catapult system, powered by a pulse-jet, and guided by a gyro compass system. By designing it for a single one-way mission, no fuel for the return was needed, no aircrew had to be carried, and the ratio of warhead to overall weight was increased dramatically. The loss of self defence capability, and inability to carry out target identification reduced the effectiveness of the weapon system. The V-2 ballistic missile overcame the vulnerability problem of the air-breathing V-1. Small unguided rockets had been developed during the war for air- to-air, anti-tank, artillery and anti-submarine use. The V- 2 was a quite different weapon. It weighed 28,504 lbs at launch including a one ton warhead. All the fuel was carried internally, and it was fired to an unprecedented altitude of some 70 miles before descending ballistically towards its target. The maximum horizontal range was 200 miles, and its velocity at target was 3,500 miles per hour (8). Here was a weapon so novel in its flight envelope that the air defences were totally impotent against it. The new technology carried penalties. Guidance was difficult, and small errors during the early powered stage, led to large inaccuracies at the target. The high terminal velocity reduced effectiveness by burying the warhead too deeply. Nevertheless the V-2 pointed the way to the missile age which was to come. T

he second technological breakthrough to affect the future of air power was the production of a working atomic bomb. The use of air delivered atomic weapons at Hiroshima and Nagasaki made the strategic nuclear bomber the centrepiece of air forces' post war development. The weight and size of the early atomic bombs made it difficult to imagine them being delivered by anything but the most powerful aircraft.

The third technological advance offered increases in power, speed and altitude through a new power source: the jet engine. So long as aircraft propulsion depended on the propeller, the aircraft would be limited by the tip speed of the blades. The principle of the jet engine was not new. A patent for a gas turbine had been issued in 1791. However it took developments in materials to provide components which could be machined with precision and yet withstand the very high temperatures and stresses. The Whittle patent for a gas turbine aircraft engine was published in 1930. Yet the subsequent development was remarkably slow. The first jet aircraft, the Heinkel He 176 flew in 1939, yet it was 1944 before the first jet fighters were used in combat. As the power available from jet engines has increased, and designers have sought greater performance from aircraft, the manufacturing tolerances of every part have become more critical. Greater understanding of aerodynamics has improved performance yet further. The sound barrier proved to be conquerable and supersonic aircraft developed. The penalty associated with increased performance was one of cost and fuel consumption.

In looking at the development of aerospace power since 1945, it is possible to argue that there have been enormous technological advances, which were impossible to foresee, yet at the same time the application of technology to countermeasures has negated many of the enhancements. The one result from technological progress has been rapidly increasing unit costs of aircraft. Considering each of the roles which air power plays in modern warfare, it is possible to determine where technology has significantly enhanced capability.

The earliest use of the air was for reconnaissance and that remains a vital part of military capability today. The jet aircraft allowed higher altitudes to give greater coverage, and slant viewing from safe territory. The vulnerability of high flying aircraft to modern air defence systems has reduced the effectiveness of such aircraft near hostile airspace, but they may be the only method of obtaining rapid large scale survey information. This strategic reconnaissance can also be obtained from satellite based systems. The successful placing into orbit of Sputnik 1 in 1957, heralded a technological development which has had many implications for future wars. The reconnaissance information available from the wide range of sensors in space provides much better overall coverage than would be available from aircraft. There still remains an important role for the reconnaissance aircraft when specific areas need to be studied, and also in the tactical situation. In the latter, the aircraft is likely to be flying at very low level, at high subsonic speed, and using visual, infra-red and radar sensors. In this respect it is an evolutionary development from the photo-recce aircraft of the last war. There are however two forms of air reconnaissance which represent significant new military capabilities. The first is the airborne early warning aircraft carrying powerful radar systems, and the associated data processing capability which allows it to act as a flying radar station which can control an air battle. The second is the parallel surveillance system for providing real time detailed information for the land battle. The Joint Surveillance Target Attack System (JSTARS) can locate moving ground targets up to 100 miles away.

The bomber has also evolved in the intervening years. The evolution has not been as dramatic as is characterised by the high technology appearance of the modern supersonic bomber. While high speed and high altitude seemed important qualities in the early days of the nuclear jet aircraft, air defences for a long time forced the bomber to plan on very low level operations. The problems of terrain avoidance and fuel consumption at these heights have effectively limited speeds to the high subsonic region. A comparison between the Lancaster bomber of World War 2, and today's Tornado is illuminating. The Lancaster flying at medium altitude could carry much the same bomb load over nearly twice the distance as the Tornado, which flies at just over twice the speed on an operational sortie. It took a crew of 7 to operate the Lancaster, against the Tornado's two man team, and it cost just £45,000 in 1945. Taking normal price inflation into account, a Tornado would cost cost 25 times the 1996 cost of a Lancaster. This crude comparison of speed, bomb load and combat radius hides the transformation in the operational environment over the 40 years. The Lancaster could not reach the target against the modern air defence systems, and the high cost of the modern offensive aircraft reflects the necessity of the technological fixes to improve its survivability. The technology increases effectiveness as well through all weather operation and greater accuracy of weapon delivery. The price of this technology reduces the total number of aircraft available. The balance between these two factors will determine whether offensive air power is of increasing or diminishing importance in future wars. The newest United States bombers have focused their technological development on reducing visibility to radar. The use of stealth techniques in materials and shape have multiplied the cost factor yet again.

One area in offensive air operations, where technology has been relatively slow to provide new capabilities has been in the weapons themselves. Conventional bombs have developed relatively slowly. The major thrust has been towards greater delivery accuracy through some form of guidance. Laser target marking has allowed precision bombing, when conditions permit the designation of the target. Design of bombs specific to targets has been slow in coming, but a range of specialist munitions are now entering service. The unit costs of such weapons are significantly greater than those of the dumb iron bombs. The Gulf War of 1991 saw the use of airfield-denial weapons, anti-radiation missiles, laser-guided precision bombs, and air-launched cruise missiles with precision target finding systems.

The primacy of the strategic bomber for nuclear deterrence was lost in the 60's as the ballistic missile became a much more certain way of delivering nuclear weapons to strategic targets. The coupling of nuclear weapons to ballistic missiles has been the major technological achievement of the post-war era. Mutual deterrence depends on an assured nuclear retaliatory capability, and the wide variety of nuclear systems available provided this. The development of multiple warheads for these missiles, different basing methods, and cruise as well as ballistic delivery, made the retaliatory capability even more assured and reinforced deterrence. Guidance systems have improved to the extent that singular military targets can be held at risk as well as area economic targets. As the world moves away from the nuclear confrontation of the Cold War, there is a decline in interest in nuclear weapons for aircraft delivery.

Moving to air defence, the development of the air defence missile has transfomed the way in which aircraft must operate. Missiles can be guided visually, by radar and through heat seeking sensors. All these guidance systems work in straight lines, and if located on the ground will have a minimum effective altitude. This gives a higher chance of survivability to the low flying aircraft, although they will remain vulnerable to modern fighters looking down on them. An alternative countermeasure is to fool the air defence sensor system through jamming or deception. The developments in electronics have made this an area of much greater importance in modern warfare. Fighters have changed significantly in effectiveness: from the guns operating at close range of 1940, the modern fighter need never see its target. Long range radar allows an enemy aircraft to be destroyed with air-to-air missiles at extended ranges. More than one target can be engaged simultaneously, and the fighter can remain on airborne alert for long periods through air-to-air refuelling. The real cost of the modern fighter has increased by even more than the bomber. The increased capability to defend against enemy aircraft is limited by the difficulties in positively identifying distant targets as hostile or friendly. Technology has yet to provide a satisfactory unambiguous solution to this problem.

The post-war period has seen technology enhancing the ability for offensive aircraft to penetrate to their targets, and at the same time for defensive systems to prevent that penetration. The consensus view appears to be that the defensive systems are winning in this technological battle. Future aircraft are unlikely to be able to penetrate close to heavily defended targets, and will depend increasingly on weapons which can be fired at a distance from the target.

Looking next at the developments in air transport, the first major crisis after the War showed through the Berlin airlift the strategic nature of massive airlift capability. Almost without noticing, the comparatively lower technology of the transport aircraft has brought a new concept to military force. Governments have been able to shape defence policies around their ability to deploy forces by air to remote trouble spots. The large carrying capability, coupled with in flight refuelling, has made reinforcement over thousands of miles possible in a matter of hours. For many operations, the provision of air transport is seen by Governments as their major contribution. The operation to feed starving Kurds from the north of Iraq immediately after the Gulf War required extensive air transport. Supplying Sarajevo following the break up of Yugoslavia was an air lift operation to bring back memories of the Berlin air lift.

Maritime aircraft have benefited from the improvements in navigation equipment, carrying capability, range and stand off weapon systems. In terms of a breakthrough in ability to detect and destroy submarines, the process remains as much an art as a science. Technology has provided novel aids which can detect magnetic anomalies, relay acoustic information, and enhance all the sensor information, collate it and display it. The submarine which wishes to stay hidden still has the advantage.

In aircraft design a major change has been the move away from dependence on increasingly vulnerable runways. As aircraft became bigger and more complex, they became more demanding in their requirements for prepared take off and landing surfaces. This made airfields attractive targets to reduce enemy air effort. In many cases airfields may not be conveniently located. Two developments have made certain aspects of air power independent of runways. The first was the helicopter. First used in the Korean War, it was a rescue and medical evacuation vehicle. Experience in the Vietnam War showed how versatile the helicopter could be for reconnaissance, command and control, transport, and as a firepower platform. Helicopters are now fitted with a range of armament for close air support roles, and have a rapidly growing place in nations' inventories. Technology has improved the lift capability, the handling characteristics and the weapons available. The vulnerability of a relatively slow moving and fragile aircraft remains a problem. Nevertheless, there are those who would argue that the armed helicopter is the tank's successor, and the cargo helicopter can replace the armoured personnel carrier. This would make the ground forces more mobile, and less easy to obstruct. A judgement of whether cost and vulnerability will be the limiting factors will have to await more combat experience.

The second method of removing dependence on runways has been the development of fixed wing aircraft with vertical take-off and landing (VTOL) capability. What at first seemed an innovation of limited application has now been proved through the contribution the Harrier was able to make in the Falklands Conflict of 1982. The flexibility offered by such a high performance aircraft operating from dispersed field sites, or from small ships, has not been taken up as widely as might have been expected. There are logistic support and aircraft performance penalties associated with VTOL operations. However under some circumstances it may be the only way of operating.

For military vehicles operating in the earth's atmosphere, there have been surprisingly few major changes in concepts since World War 2. The advent of the air defence missile, has forced the pace of countermeasures. Aircraft fly lower and faster, but no further than before. The maximum possible speeds and altitudes are no longer sought after. While demands for operating bases grew more stringent initially as aircraft became more complex, technology has been moving towards reducing such dependence. Apart from helicopter operations, concepts for the use of air power today are not very different from those of 40 years ago. Technology has improved capabilities, but the battle remains the same.

Since 1957, the regions beyond the Earth's atmosphere have assumed increasing importance to national security. Technology has made Space the extended battlefield. The military uses of Space have developed at a remarkably slow pace. While larger payloads have been placed in orbit, and modern electronics and computer technology allows much more capability to be given to any payload, the costs of Space systems remain extraordinarily high. In the first 3 decades of this century aircraft moved from the Wright Flyer to a worldwide use of aircraft for offensive, defensive, reconnaissance and transport. In the 40 years since Sputnik 1 was placed in orbit, progress has been much less dramatic. The use of satellites has assumed increasing importance for reconnaissance, communication, and navigation. The ability to launch such systems remains in the hands of very few nations.

Military reconnaissance satellites are used for photographic survey, electronic information gathering, missile early warning, meteorological data gathering and for geodetic measurements for missile targeting. These all represent quite new capabilities in scale of information which can be collected. Military communications are becoming increasingly dependent on satellite relay, although it was of note that in Bosnia in 1995 the Press had more efficient satellite communications than the UN forces. While long range communication has been possible through HF radio, propagation has at times been unpredictable and data density was limited. Communications satellites offer comprehensive high density communications over very great distances,and allow control to be retained at much higher levels than before. Satellite based navigation systems allow military systems to fix their positions to unprecedented degrees of accuracy, with significant implications for weapon delivery accuracies.

In these ways space technology has added to military capabilty. The cost of the systems is high, and the reliability of launch systems remains less than perfect. Satellites coul be extremely vulnerable to a number of countermeasures. By their nature they are in exposed positions, which are easily located. The then Soviet Union tested an anti-satellite weapon system based on an exploding satellite. The USA developed an anti- satellite missile. The UK was reported in 1995 to have conducted tests aon interference with GPS signals. Some reconnaissance sensors may be possible to damage by high energy laser directed at them from the earth. Technology has provided at a high cost space-based systems which become increasingly relied upon for command, control, communication and information. Yet the capability is also a vulnerability if anti-satellite systems are being developed. The further potential for the military uses of space are explored in Chapter 8.

Since the beginning of the twentieth century technology has made air power, and latterly aerospace power, of increasing importance. The ability to move away from the restrictions of movement on the Earth's surface offers a new arena for military conflict. The lessons of the past suggest that our predecessors found it difficult to make the right development decisions in a timely way. Extrapolations of limited combat data resulted in false strategic concepts. With the benefit of hindsight, the technological developments which have crucially affected aerospace warfare are the invention of the aircraft, radar, nuclear weapons, and the missile. It may be that the future historian will place the helicopter/VTOL aircraft, or satellites among these milestones. Alternatively their vulnerability may mark them down with the airships of the past.

The characteristics of the four major technological areas may give some direction to thinking about future possibilities. The aircraft offered a new scale for firepower in both range of action and speed of reaction. It gave a new flexibility to the use of military force, which could be applied to a whole range of widely separated targets. Radar made the invisible visible. The vast regions of the sky or the sea could be explored at the speed of light, and appropriate countermeasures taken. Nuclear weapons provide destructive power on a scale unimagined before. Indeed with thermonuclear weapons, the energy released was virtually unlimited. The potential damage from even a single weapon changed the whole nature of international relations. Finally the missile provided an unstoppable delivery method for the nuclear weapon. As we examine the opportunities for the future, the relative effectiveness of the manned aircraft against the missile will need close scrutiny. The future applications of space technology will also need to be examined. Aerospace technology grows ever more expensive, and yet concepts have not made dramatic changes in recent times.