Can Aircraft Be Limited?

IN THE disarmament equation aviation is still a factor x. It is still preëminent among the difficulties, and so among the obstructions to success on a comprehensive front. In 1932, as on every other occasion since the World War when the matter of arms limitation has received concerted attention, the technical problems of the air arm are the most baffling that have to be solved. In air forces there are no universal units of measurement. There is no sharp distinction between one type of aircraft and another such as can be drawn, for example, between battleships and cruisers. There is no generally acceptable yardstick, corresponding to tonnage in naval vessels, for the simple expression of relative collective strength. There is not even any sharp line of demarcation between military and non-military craft.

Limitation, difficult enough at best for technical reasons, is made harder by the mystery which envelops the possible uses and effectiveness of aircraft in war. Opinion is by no means agreed on these points. Some military men and a vast number of civilians have come to take it for granted that the next war will be fought almost exclusively in the air, and that it will be ended within a few hours or a few days by the destruction of all the great populous centers in the territory of the less well-prepared of the combatants. Opposed to this opinion is that of most students of military and naval affairs, who take such forecasts with many grains of salt. Those responsible for national defense are not persuaded that aircraft make other arms obsolete. Uncertainty is inherent in the nature of the air arm and in the conditions under which aircraft are constructed. An air force, unlike a navy or a powerful army, can conceivably be built under cover; and in the hands of a treacherous neighbor it can strike in the dark.

Confronted by technical difficulties, by divided opinions, by lively fears, it is not surprising that responsible government officials, or at least most of them, are inclined to rely on air forces of their own rather than on pledges as a safeguard against the aërial threat. Hence, statesmen and soldiers alike are highly suspicious of any attempt to restrict their nation's development of air power.

The most sweeping proposal for limitation comes from those who believe that any air armaments at all are bound to wreak destruction upon civil populations in the next war. They have found a norm in the military aviation causes of the Versailles treaties, by which the defeated countries have been deprived of all air armaments since 1919. Taking that as pragmatic proof that a nation can exist without an air force, they have advocated a world-wide abolition of military flying, putting all countries upon the German level. This plan has been most actively promoted by M. Henri de Jouvenel, Viscount Cecil and Sir Gilbert Murray, and has attracted some support in Germany.

The abolition of military aviation, if it could really be enforced, would be greatly in the British interest, and it is conceivable that the British delegation may put forward some suggestion of the sort at Geneva. Such a proposal might be accepted by other countries as an economy measure and to assuage the fear of bombardments of undefended cities, provided military aviation could be accurately defined and provided the fear of aërial surprise by a treacherous neighbor could be overcome.

But experience in enforcing the aërial clauses of the Versailles treaty has shown that it is next to impossible to draw a hard and fast boundary around military aviation. In 1919 Germany was beaten and disarmed. There was practically no limit to the conditions which the Allies could impose upon her. The famous "nine rules" of 1920 were designed to take into account everything which could make an airplane fit for military service. They seriously handicapped the development of German air transport. They set up conditions so harassing and so humiliating that no state could ever be expected to accept them except under compulsion vi et armis. Yet, even so, they failed to satisfy Germany's former enemies that military aviation was really excluded, and in particular they failed to allay French alarm over the alleged development of great German military air strength under the guise of civil flying. French authorities have frequently declared that France, with four or five thousand military planes, is outclassed by Germany's three or four hundred air transport craft. Needless to say, if military aviation were abolished in all countries civil flying would be watched with greatly intensified suspicion.

As a way out of all these difficulties M. de Jouvenel and Viscount Cecil have suggested the internationalization of civil aviation. The suggestion is somewhat vaguely defined, but apparently it comprises the joint international operation of air transport routes, the abandonment of governmental stimulus to national aircraft industries, and the formation of a cartel to allocate and control aircraft production.

So all-inclusive a proposal could only have come from countries where, generally speaking, civil aviation means subsidized air transport and where the private ownership of airplanes is on a very modest scale. At the present time there are three airlines from western Europe to southeastern Asia -- the British "Imperial Airways," the French "Air-Union Lignes D'Orient," and the Dutch "Koninklijke Luchtvaart Maatschappij," more generally known as the "K. L. M." They follow roughly parallel routes and have kindred purposes. All three are generously supported from the public purses of their respective states. To internationalize them would be relatively easy. It might perhaps be feasible, though much more difficult, to internationalize the route from Miami to Cristobal and down the west coast of South America. It is even remotely conceivable that some form of international supervision might be devised for purely domestic air transport operations (such as flourish in the United States to the extent of about 150,000 miles of flying per day) provided they are supported by the governments in question. But how, short of the formation of a World State, would we set about internationalizing a transport line which is completely independent of government support and runs as an ordinary commercial enterprise? By what imaginable means could one internationalize the operation of the aircraft -- faster than some fighting planes and with more carrying capacity than some bombers -- employed in the service of the Detroit News and of the McAleer Auto Polish Company? How internationalize the operations of Mr. Wiley Post's world-girdling Winnie Mae, or the aërial activities of Mr. Wallace Beery and a thousand other private fliers? These are not mere trivia. French alarmists often allude to the Sportflieger Vereine, groups of young Germans banded together to learn to fly and practising the art on machines of insignificant power and performance. It is apparent, then, that when civil aviation is considered in the broadest sense, in the sense in which it is actually developing, "the internationalization of civil aviation" becomes a phrase of very limited application.

On the whole, however, the principal proposals from British sources are for the abolition of military aviation. That was M. de Jouvenel's original idea also, but he has recently modified it, and now proposes that military aviation be retained, but that it be reserved as a weapon of the League of Nations. The proposal for such an international air force was first pressed by Mr. Clifford B. Harmon, an American long resident in Paris. The Preparatory Commission gave his suggestion a chilly reception. It can at least be said in its favor that from a purely technical point of view the creation of an international force would bring the abolition of national air forces further within the realm of possibility than it would otherwise be. As a practical matter, however, Great Britain and the United States seem likely to oppose this scheme, just as they have opposed other plans for putting force at the disposal of an international organization.

Discussion of plans for internationalizing aviation has had one good result; it has brought out the necessity of drawing a sharp distinction between military and civil aviation in government policy, and has convinced most nations that civil enterprises should not be supported by their governments for purely military reasons. This principle was adopted at a conference of civil aviation experts held at Brussels in the spring of 1927, and is included in the Draft Convention prepared by the Preparatory Commission.

The officials of commercial airlines have as a rule no military interests. In most instances they insist on financial support from their governments, but they would much prefer that it be given on purely commercial terms. The Brussels meeting of 1927 brought together a committee of which about one-third of the members were actively engaged in the operation or promotion of air transport enterprises. Most of the others were officials in the civil aviation branches of their governments. The committee had comparatively little difficulty in agreeing that:

It is desirable that the development of civil aviation should be directed solely towards economic ends, and should remain outside the sphere of military interests.

Civil aviation should be organized on autonomous lines, and every effort should be made to keep it separate from military aviation.

If states intervene in any capacity, whether directly or indirectly, in civil aviation undertakings, it is desirable that the state organizations dealing with the matter should be quite separate from the organizations dealing with military aviation.

It is desirable that governments should refrain from prescribing the embodiment of military features in the build of civil aviation material, so that this material may be constructed for purely civil purposes, more particularly with a view to providing the greatest possible measure of security and the most economic return.

As regards personnel, and in particular pilots, it would be desirable that civil aviation undertakings of all kinds should not require such personnel to have received a military training or give preference to those who have received such training.

It is a fortiori desirable that these undertakings should as far as possible avoid seconding personnel from military to civil aviation for the purposes of the latter.

The Committee desires to point out the undesirable effects which may result from the direct or indirect encouragement by governments of civil air transport lines for military rather than for economic or social purposes.

At the present time civil aviation in most cases has become national in character. It would seem desirable to encourage the conclusion of economic agreements between civil aviation undertakings in the different countries.

All of these points have been incorporated, in essential spirit, in Article 28 of the Draft Convention. It is rather surprising, however, and typical of the confusion pervading the whole subject because of its technical novelty and the diversity of government policies, that the most strenuous objections to Article 28 have come from two of the most pacific of states, Sweden and Canada. Both have a special situation. Both have a great amount of survey work and emergency transportation to carry on in thinly settled or completely unsettled regions, and quite innocent of any military purpose are using military personnel for these operations. Both object to restriction on such use. From the continental countries in which commercial air transport has a really military purpose and flavor, on the other hand, there comes no word of protest. We may suppose that they will still be able to accomplish their purposes by indirection, without offense to the letter of the Draft Convention.

Article 28 of the Draft Convention (echoing the call of the last paragraph quoted above from the expert committee's report) falls far short of true internationalization. What it asks for has, in fact, already been largely attained. Already it is common practice for the airlines between European centers to be operated by agreement between the major air transport companies of the countries concerned. The agreements, however, do not touch on questions of equipment or personnel. They are the outcome of purely economic competition, with the governments participating only to the extent of refusing to sanction penetration by a foreign airline except on a basis of complete reciprocity and equal division of activity. Thus, the Deutsche Lufthansa and the Compagnie Générale de Transports Aériens both maintain services, with equal schedules, between Paris and Berlin. This division of traffic may produce some coöperation between the companies concerned, but it does little to allay international suspicion or to promote the reduction of air armaments or limit the applicability of transport material and personnel to military purposes.

Articles 28 and 34 of the Draft Convention, the latter calling for complete publicity and periodic reports on the scope of civil aviation and the number of planes in civil employment in each country, represented a compromise on the most bitterly argued of all the aëronautical problems that came before the Preparatory Commission. It would be foolish to pretend that the compromise is generally satisfactory. Undoubtedly the whole question will now be reopened and fought over at Geneva. The dissatisfaction of certain nations with any solution that may be reached will stand in the way of any effective determination of the ratios or numbers to be used in limiting military air forces.

If civil aviation were actually internationalized, perhaps this perpetually discussed question of the extent to which civil aviation is a useful military auxiliary would not arise. Under present conditions, however, it insists on arising, and in seemingly insoluble form. As has so often been found the case in efforts to limit armaments, the nations divide sharply into two groups on the problem of civil aviation control, -- on one side the French bloc, and on the other an Anglo-American-German-Scandinavian grouping. France, with an air force approaching a two-Power standard in strength, with very little civil aviation and a people who show little inclination to develop flying as a sport, has argued that military and civil aviation are completely interchangeable and that limitation must be applied to all aërial activity as a unit. The American and German delegates, with the partial concurrence of the British, have maintained that civil aviation is of negligible military significance, that the economic results of any attempted control of civil development would be disastrous, and that limitation must be confined to military material and personnel, including the reserve.

As a matter of fact neither extreme view is supportable. To assert that a civil plane is the equal of a military plane in value, especially without reference to its power, size or performance, is preposterous. To claim, as the American and German representatives on the military subcommission of the Preparatory Commission at one time did, that "civil aviation as such is of comparatively little value as a war armament" may be true if the definition of the word armament is very narrowly restricted, but in any broad sense it is much exaggerated. It is in direct opposition to the opinion of most experts who have written on the subject, including those of American and German nationality. It is also refuted by the fact that war and navy departments and air force officials everywhere display keen interest in the progress of civil aviation, and by the known fact that civil aircraft were pressed into emergency transport service during the recent French Army manœuvers and proved to be of great value. It is probably correct to say that civil aircraft, with very rare exceptions, cannot readily be adapted for fighting, or even for bombing places that are well enough defended to hold the bombers to a high altitude. The trained personnel, however, constitute a resource of immense value, and a great proportion of the civil machines can be put into auxiliary service -- for example, for transport duty, the making of observations in quiet territory, or even the bombing of undefended places.

If there were nothing to be considered except the reaching of an agreement that would establish and maintain certain ratios of air strength among the contracting Powers, the most reasonable point of view would be the intermediate one that limitation should apply directly only to military aviation, including reserves of military material and of specially trained personnel, but with the development of civil aviation taken into account as one of the modifying factors. That method is impractical, however, because civil aviation is important in different degree for the various states and also because it has been developing so rapidly and because it seems undesirable to impose any restriction on its natural growth for peaceful employments. The Brussels committee of experts, already referred to, expressed itself very strongly on the disadvantages of taking civil flying into account at all in arriving at a system of limitation.

The committee further condemned, as sure to have serious economic consequences, any restrictions on the characteristics of civil aircraft. Limitation in terms of performance or of such generally used engineering ratios as weight per horsepower has often been suggested (the possibilities were analyzed in some detail by the present writer in FOREIGN AFFAIRS, July 1926). In declaring itself opposed to anything of the sort, the Brussels committee expressed its opinion that, in the light of the failure of the attempt to define military aviation in Germany and of the rapid development of the art of flying, no rigid definition or line of demarcation could be drawn. The Preparatory Commission accepted that non possumus.

The problem of definition is becoming no simpler with the passage of time. Half a dozen years ago, when the writer was preparing the article just referred to, it seemed very probable that military and commercial design in aëronautics would diverge just as had been the case with seagoing craft, and that it would become comparatively easy to draw the line between types. The contrary has occurred. There has been an increasing demand for commercial airplanes of very high speed and climbing capacity. Although specialized military craft are still to be distinguished by the provision that is made for the installation of various specialized items of armament, the differences in military and commercial planes in inherent performance and in general design characteristics are fewer now than they were in 1926.

If civil aviation is to be excluded from the account, and if no one is able to devise a way of saying precisely what civil aviation is, limitation is obviously to be confined to those air forces which their governments frankly avow are military. The provisions of Article 28, though helpful, are so vague that they cannot be put into rigid effect. The fact is that it was necessary to dodge the question of civil aviation in the Draft Convention. It almost inevitably follows that reserve material will be ignored and that limitation will be applied only to planes actually in full commission as a regular and permanent part of the equipment of a regular military air force. The Draft Convention (Article 25) proposes that "the number and total horsepower of the airplanes, capable of use in war, in commission and immediate reserve in the land, sea and air arm forces" shall be restricted.

It is not only in respect of civil aviation that the aëronautical sections of the Convention suffer from vagueness. Indeed, they contrast very badly with other portions of the document. The paragraphs dealing with naval questions are (with the single exception of that covering the definition of an aircraft carrier) clear and concise. But the aërial clauses, prepared largely by statesmen with some knowledge of military and naval affairs in general but with no specific experience in aëronautical matters, are full of loopholes and doubts.

For example, there is the question of "immediate reserve." At what point does a reserve cease to be immediate? Obviously the term includes the machines directly attached to squadrons in the field and held for replacement in case of minor damage to some of the operating equipment. Obviously it excludes planes in dead storage, bought solely against a possible emergency need and left stored in the original crates. But does it include a general reserve held at a depot into which all squadrons turn their machines for occasional overhaul and from which they draw new ones? Does it include craft held for the replenishment of the supply of military flying schools? No one appears to know.

Even more perplexing is the phrase "capable of use in war." The reports furnished to the League of Nations by various Powers regarding the state of their armed forces already give evidence of the greatest confusion on this point. Some reports include everything that will fly. Some exclude experimental types. A number of them exclude primary training machines. Some exclude transport and other utility types. Yet every one of those is "capable of use in war" in some capacity or other. Seemingly the phrase is being accepted in many cases as meaning "capable of effective use over the front lines." Obviously, even if the wording were so changed, there would still be room for immense differences of opinion and interpretation.

In spite of the vagueness of the Draft Convention where aëronautical matters are concerned, and despite the prevailing unwillingness to do anything that will interfere with technical development in the air, it is surprising to find no attempt whatever to control the properties of individual aircraft or to treat them as individual units. The global method of limitation, hotly opposed by all the great naval Powers in its application to sea forces, has had its triumph in the air. Indeed, there has been a substantial sentiment in the Preparatory Commission in favor of limiting only the total number of planes, without any reference whatever to their strength as individual units or in the aggregate. In opposition, various groups of nations endeavored to secure limitation of aggregate strength by various technical devices which would give those nations an advantage either over the world at large or over some traditional foe.

The relative insignificance of the points upon which these struggles for national advantage sometimes turn is a reminder of the extent to which the presumably general desire to reach agreement for the general good is subordinated to considerations of national advantage, and also of the importance of having highly competent technical personnel close at hand during the discussions of such matters. Most of the delegates are immensely interested in the problem of disarmament and have lived with it for a number of years, but nothing in their experience has qualified them to conduct a lengthy and detailed argument on the relative advisability of limiting aircraft by aggregate horsepower or by aggregate wing area.

It happens that differences in national practice in airplane design are much more marked than exist in the designing, for example, of naval vessels. Thus, to mention only a single instance, British airplanes almost invariably have wings of relatively thin section with a large amount of external bracing to support them, while the German and Dutch practice is to use much thicker sections and carry the structural bracing internally. French and American designs vary between the two extremes. The result is that the British have to use somewhat more wing area to get the same result than do the builders of other countries, and as a natural result the British delegation were hotly opposed to use of wing area as a measure of air force strength. The Germans, the Dutch and the Americans, on the other hand, were enthusiastic in its favor. Agreement was finally reached on the use of aggregate horsepower as an index.

The battlefield was thereupon shifted to the definition of horsepower. German engines run at low speed and use larger cylinders than are conventional in other countries for developing the same power. The German representative on the special technical committee which was charged with the development of the horsepower formula was consequently in favor of taking horsepower, for the purposes of limitation, as directly proportional to engine weight. The American and French delegates preferred to make it depend on cylinder volume alone. A compromise was finally reached which includes both factors, but which appears to be distinctly unfair to typical German engines. It will result in giving the German, for a given nominal limitation on horsepower, from ten to fifteen percent less power actually developed in flight than the French, for example, could secure under the same figure. Of course the Germans, or any other country aggrieved by the working out of these rules, will have the option of changing their design practices, but it is not easy to do that within a short time. Through all these debates the delegates of the several states have played the parts of so many marine architects trying to develop designs for new yachts which will "beat the rule" under which handicapping is done, except that in this instance the endeavor is not to create something new that will beat an existing rule but to secure the adoption of a rule that the existing practice will beat.

But though there are plenty of flaws and ambiguities in the Draft Convention it would be unfair to leave the subject without paying tribute to the spirit of compromise that made it possible to draft any convention at all. The problem is immensely complicated and the agreement reached is imperfect; still it is an agreement, and it is a far better one than seemed likely in 1927, when the Preparatory Commission was holding its third and most arduous session.

The technical points mentioned above would be trivial if the nations were possessed of a general and genuine will to find means for limitation, together with a reasonable degree of mutual trust. The complexity of the problem of the air arm will have a decided effect on the success or failure of the Conference, but it is a somewhat indirect effect. If the Conference fails to limit air forces, the technical difficulties will be a plausible excuse rather than the underlying cause. The real sources of the trouble will be in the state of feeling in Europe, particularly the uneasiness among the neighbors of France about the French determination to make security the precursor of disarmament, and the resentment of the German Government and people over the aërial clauses of the Treaty of Versailles. The first points are more or less obvious, and apply in some form or other to all attempts at arms limitation in any field. The last, which is the most important, has a special aëronautical twist.

At the time of writing the German attitude on armament ratios has not been defined. We have yet to see what measure of inferiority to France the German delegates will be prepared to accept in a treaty which they are under no compulsion to sign. It is at least possible that in dealing with land and sea forces some turn of phraseology can be developed which will avoid a flagrant departure from the terms of the Treaty of Versailles, and still be acceptable to the German Government. In respect of air force such an outcome is quite unthinkable. The Treaty says in plain language that Germany shall have no military air force whatever. That any German delegation will of its own free will sign a document perpetuating that state of affairs is as inconceivable as that an American delegation would voluntarily accept naval inferiority as against any other nation. It is only a little less inconceivable that France will permit any explicit modification of the Treaty's terms. There lies the dilemma. It seems well-nigh insoluble.

A really substantial reduction of air forces is probably less likely than a reduction of any other form of armament. The air arm is in process of development and expansion, and armies and navies are becoming ever more dependent upon it. Aircraft are now a part of the equipment of every large naval vessel and of every unit of troops in the field. At the present time, for instance, the United States Navy has only about 200 airplanes based on aircraft carriers. On the scale on which planes are now planned for these ships, with a much larger complement for each vessel than was thought possible four or five years ago, the total number needed to equip all the carriers that we are allowed under the London Naval Treaty would be about 750. Similar situations exist in certain other navies. The technical advisors of most of the delegations, then, are likely to declare themselves seriously dissatisfied with their present standard of air strength, and desirous of stabilizing at a considerably higher figure. Unless there is to be a very drastic reduction indeed in the general standard of surface armaments, any agreement affecting air forces is likely to permit a general building up to somewhat above the present levels.

As an alternative or supplement to the limitation of numbers and power of planes and of the personnel of air forces -- especially should agreement on those points prove extraordinarily difficult -- the Conference is likely to make an effort, by amplifying the laws of war, to limit the ways in which planes may be employed. There has been much discussion during the past winter, particularly in British circles, of the feasibility of abolishing aërial bombardment. The Conference has had a timely object-lesson of the destructive possibilities of that form of attack laid at its very doorstep, for two days before it convened in Geneva the Japanese bombed a section of Shanghai, and are reported to have killed 150 Chinese by a single bomb falling on a railway station.

The suggestion that attack upon ground objectives from the air be abolished will not be entirely new to the delegates at Geneva. The proposal has already been broached only to be repelled, though not decisively. During the Preparatory Commission's sixth session, in 1929, the German delegation proposed the inclusion in the Draft Convention of a provision that: "The High Contracting Parties mutually undertake not to launch weapons of offense of any kind from the air by means of aircraft, nor to employ unpiloted aircraft controlled by wireless or otherwise, carrying explosive or incendiary gaseous substances. They further undertake to make no preparations of any kind for the use of such weapons of offense." M. Litvinov, following usual Soviet policy, not only welcomed the German suggestion but went further, declaring the Soviet Government's desire that all implements of war directed primarily against civil populations should be forthwith destroyed. The other delegates who spoke, and there were many of them, damned Count von Bernstorff's proposal with faint praise. On a record vote, only the Swedish and Dutch representatives and one other joined MM. von Bernstorff and Litvinov in supporting it.

The defeat was indecisive, however. A number of the delegates who voted against the proposal, including those of the United States and Great Britain, did homage to the spirit that was presumed to animate it and explained their votes as due solely to the conviction that the Draft Convention was not the place for prohibitions, nor for a fixing of the laws of war. It may be remarked in passing that no such considerations restrained the same delegates from voting at the same session to include in the same Convention an absolute prohibition of bacteriological warfare and a limited prohibition of gas warfare.

The delegates who voted down Count von Bernstorff's motion, not desiring to be left in the position of upholding indiscriminate aërial attack on cities, immediately and unanimously passed a resolution interpreting their own action as "not in any way meaning that the bombardment of civilian populations is authorized." The 1922 Hague Conference on the Rules of Aërial Warfare had undertaken definitely to forbid such bombardment, but only a few nations ratified the resultant convention and it lapsed into desuetude. The question promises to be a perennial one. It is quite impossible to debate the limitation of aërial armaments without involving consideration of the advisability of changing the laws of war, and quite illogical to insist on the rigorous separation of two such intimately connected questions.