Allied Air Power Doctrine: Royal Air Force War Manual; Volume I - Chapter 7: Air Warfare
The Aim
1. The justification for the existence of the fighting services is imperial security, and the special responsibility of the air forces in war is security against hostile air power. Although this responsibility is fundamentally defensive in nature, security against air attack—like other forms of attack—cannot be assured by defensive measures alone ; it ultimately depends upon a successful air offensive.
2. Security can be assured by the complete destruction of the enemy air forces, but this result will seldom be obtainable against a highly developed nation. It may be possible against semi-civilised or under-developed countries whose resources are limited and whose means of replacing air casualties, whether in personnel or material, are inadequate, but in the case of highly developed nations, air casualties, both in personnel and material, can be so quickly replaced that the destruction of their air forces is impracticable unless the sources by means of which they are maintained can also be subjected to effective air bombardment.
3. Moreover, owing to their peculiar powers of evasion and their ability to penetrate a highly organized air defence, aircraft can, within their range, proceed to any of the vital centres which may be essential to the maintenance of the enemy's fighting forces. Aircraft can, in this way, strike directly at the enemy's means of resistance by attacking objectives such as naval or military organizations, or centres of production, which, in furtherance of the policy of the Government, may at the moment contribute most effectively to breaking down his resistance. Should circumstances favour the quick destruction of the opposing air forces, that operation, if undertaken, should be regarded as a temporary though advantageous diversion from the main task of depriving the enemy of his means of resistance, or as a means to that end, and not as an end in itself.
Allocation of force to Offensive and Defensive Duties
4. The air offensive, whether it is directed against the enemy's air forces or against other objectives vital to the existence of his fighting forces, does not immediately protect our own bases from air attack, enemy aircraft having similar powers of evasion and penetration. Therefore, where the vital centres of the nation or its fighting forces are exposed to effective air bombardment, it may be necessary to provide fighter aircraft as well as other means for their direct protection, notwithstanding that offensive action is also being taken against the enemy.
5. The maxim that offence is the best defence applies even more truly to air warfare than to any other operation of war. The weakness in air defence is due to the characteristics of aircraft and to the nature of the medium in which they operate ; to their use of clouds for concealment, of favourable winds for accelerating movement and their freedom to approach an objective from almost any direction without being tied down to definite lines of communication. That weakness can best be counteracted by maintaining the initiative in offence with all its strategical and tactical advantages.
6. Aircraft employed in defence duties are diverted from the main effort and are not available to join in the air offensive, through which alone success can be finally obtained. The force allocated to defence should, therefore, be the minimum that is consistent with the adequate protection of vulnerable centres vital to the maintenance of a powerful and successful offensive.
7. Aircraft assigned to air defence will not be able entirely to prevent a determined enemy from reaching and attacking objectives within range of his air bases. Successful enemy air attacks will usually give rise to demands for more effective protection, and for the diversion of more aircraft from the offensive to the defensive. Compliance with these demands will weaken the striking force and at the same time release enemy aircraft for offensive operations.
8. If the process is allowed to continue, the weaker belligerent will ultimately be thrown entirely upon the defensive, with insufficient resources available for the offensive action which is essential to bring effective pressure to bear upon the enemy.
9. The tendency to allocate aircraft to the defensive at the expense of the offensive should be resisted, and attacks should be countered by strengthening the latter. This allocation of air resources is a problem in air strategy which requires the highest qualities of judgment, fore-sight and determination on the part of a commander.
Air Superiority
10. Air superiority is a state of moral, physical and material superiority which enables its possessor to conduct operations against an enemy, and at the same time deprive the enemy of the ability to interfere effectively by the use of his own air forces.
11. Local air superiority may be gained by the concentration of superior forces in the air at the decisive point. Even when the total number of aircraft available is inferior, local and temporary superiority at the decisive point may be obtained by concentrating to a greater degree than the enemy in either time or space. Owing, however, to the limited endurance of aircraft, such superior concentrations must necessarily be restricted both as regards period and area. By reason therefore of this power on the part of the weaker side to concentrate, numerical superiority must be very considerable in order to ensure a constant advantage in air fighting.
12. Local air superiority, such as that required over the theatre of land operations, may be produced by the careful selection of objectives for air bombardment. Heavy, accurate and continuous bombardment of the enemy's vital centres may compel him to divert a considerable proportion of his fighting aircraft to defend these vulnerable points. Where conditions are favourable, temporary advantage may also be gained by the effective air bombardment of the enemy's aerodromes. (See also Chap. VIII, para. 11 (ii).)
13. An increase in the number of aircraft allocated to air defence at the expense of offence will seldom result in a proportional increase in resistance to air attack. The attackers have all the advantage of the initiative, being free to choose their objectives, lines of approach and time and strength of attack. Moreover, a continuous defensive attitude is liable to react on the morale of the defenders, to undermine their aggressive spirit and to weaken their determination.
14. The outcome of the struggle for predominance in air power depends, within reasonable limits, more upon superior morale than upon superior numbers. Moral superiority over the enemy is a most important factor and can be gained only as a result of successful air fighting. It may be lost through prolonged defensive operations or through the constant practice—especially in the case of fighter aircraft--of evading battle. Another factor of particular importance in the struggle is superiority of technical material.
15. When the enemy is convinced of his general inferiority in air fighting, he will show a disinclination to fight at close quarters or to close decisively with bomber formations, and his resistance will weaken generally. This will tend to reduce still further his offensive spirit and there will be an inclination among his bombers to drop their bomb load indiscriminately and return to their base without penetrating to their objective, rather than face an active and vigorous defence. A further effect may be that the enemy will he led to increase the fighting strength of his bomber formations at the expense of their striking power.
16. To gain and maintain the greatest degree of moral ascendency over the enemy is one of the most important duties of all commanders and it requires constant attention and consideration.
Air Defence
17. The principal aim in air defence is to stop successful attacks being made on the defended area. If the enemy casualties are sufficiently heavy he will be discouraged from making attacks. The main effort should therefore be directed to the destruction of all enemy aircraft approaching or entering the defended area.
18. (i) A well disciplined formation of bomber aircraft can develop a formidable concentration of fire, and, so long as they are able to maintain good formation, their defensive strength is considerable and they may be able to resist successfully attack by an equal number of fighter aircraft. The defence should, therefore, aim at breaking the enemy bomber formation by the simultaneous attack of several aircraft by building up a superior concentration of fire and also by taking full advantage of the close co-operation of anti-aircraft guns.
(ii) In the future other means of disorganizing and breaking bomber formations may be evolved, but whatever the method adopted, the close co-operation of fighter aircraft is essential so that they may be available to take immediate advantage of any dislocation or disorganization of bomber formations.
19. If an enemy bomber formation is accompanied or escorted by fighter aircraft, the principal aim of the defence aircraft will be the containing or drawing off of the escort and the attack of the enemy bombers. This will require a superior concentration of fighter aircraft : nevertheless, the more the enemy can be compelled to send escorts of fighters or bombers lightly loaded, the smaller will be his resources available for air bombardment and the achievement of this result will usually be a sign that the defence is proving effective.
20. (i) Interception of hostile aircraft depends mainly on factors of time, space, information and good organization.
(ii) The principal factors influencing interception from the ground are :
(a) The distance from the advanced observation posts to the objective of enemy attack.
(b) The speed and altitude of the hostile aircraft : also, the speed and rate of climb of the defending aircraft.
(c) The strength and direction of the wind.
(d) The interval of time between the first indication of enemy approach and the departure of the defending aircraft from their bases.
(e) Visibility.
21. Interception from the ground is only possible if sufficient notice is obtainable to give the intercepting aircraft time to climb to the necessary altitude before the arrival of enemy aircraft, and the amount of notice required for this purpose will vary with the distance, and strength and direction of the wind.
22. If, owing to conditions of time and space sufficient notice of the approach of aircraft cannot be obtained—e.g., if it can only be obtained from a port or place near a frontier—the chances of intercepting them can be increased only by keeping aircraft in the air at great altitudes waiting for them. This form of interception is most exhausting and uneconomical ; it should only be used when the area requiring protection is small and when the need for the utmost measure of direct air protection is sufficiently important to justify such a method.
23. The wastefulness of this form of interception arises from the fact that if a constant air patrol has to be kept up, reliefs will be required and only a portion of the total air forces available can be maintained in the air at any one time. Since the patrols cannot be reinforced on the approach of the enemy, they must be of sufficient strength to deal successfully with the number of hostile aircraft expected : this necessitates the allocation of a large number of aircraft to the task. A further waste of energy arises because, in order to ensure that the enemy formation is engaged immediately it is located, the patrols must wait at or near the maximum altitude at which the enemy may approach. This constitutes a severe strain upon the personnel engaged and tends to reduce their efficiency, especially if the operations are prolonged. Moreover, the immensity of the zone in three dimensions which has to be guarded and the difficulty of observing from the air the approach of enemy aircraft may make such a form of interception impracticable where the area to be defended is large.
