The R.A.F., Canada, is indebted to many Canadian authorities and organizations for assistance rendered, but to none is the debt greater than to the Canadian Army Medical Corps for supplying the personnel from which the medical service of the Royal Air Force has from time to time been built up. The request was made in January by the Imperial Government that the Canadian Militia Department should supply this service. Prompt action was taken, and from a small beginning there has been formed a complete corps of medical officers, medical orderlies and nurses, skilled not only in everyday practice but also in the special work called for at flying camps.

The original intention was to supply only a small camp hospital, with one medical officer and the necessary orderlies at the various aerodromes, but it was soon determined that the work of the Medical Corps covered a much wider range than was anticipated. Almost the first need was that of skilled orderlies who were specially trained in first aid. Owing to calls from overseas, the available number of men was very small, and it was found imperative that the senior medical officer of the R.A.F. provide the necessary training. Coincident with this came a further need of isolation hospitals, which, although the general health of the brigade was maintained at an unusually high standard, were found to be essential in order that the work of training might not suffer in the least degree.

The responsibilities undertaken by the medical department were made the more onerous, not only because an extremely low percentage of class “A” men were enlisted—and these only owing to their possession of invaluable technical ability, but also because the community at large suffered from severe civilian epidemics of scarlet fever and influenza. Surgical work, with dental surgery—which latter covered many major operations owing to crashes resulting in broken jaws and teeth—comprised a considerable part of the duties performed.

A modern operating room was completely furnished at each aerodrome, together with X-ray equipment at the “out-stations.” In the autumn of 1917, the medical orderlies were further aided by the introduction of nursing sisters. For these also we are indebted to the Canadian Army Medical Corps, and without question their work has been of the highest possible advantage. Thus, by degrees, the medical staff of the Royal Air Force increased its personnel, the burden of its duties and the value of its services.

Ambulance equipment was of prime importance. A Packard machine, provided with a special type of shock absorbers and every possible requisite, not only for first aid but also for fire extinguishing, was stationed at each field, and remained on constant and watchful duty from the time the first aeroplane took the air till the skies were empty for the night. So close was the lookout, that “first aid” was often tearing full-powered to the rescue before the crash completed its descent. The ground traversed being often rough and devoid of roads, it was imperative that the ambulances be perfectly cushioned, lest the condition of “shock” as frequently found in “crash” be aggravated by the journey home. It is hardly conceivable that there could have been found vehicles better designed for the purpose than those selected, and unquestionably lives were saved in consequence of their use. Chemical extinguishers and asbestos blankets, the latter introduced for protection of the pilot in case the crash was in flames, were also carried as part of the equipment.

For winter purposes at outlying stations, the aerial ambulances shown herewith were evolved. With a wide radius, landings could have been made in any suitable, snow-covered place, however inaccessible by motor transport. They were never to be used by the R.A.F., Canada.

In this connection it is interesting to note the degree to which the duties of the medical officers in flying camps varied from the more or less regulated routine met with in other services. The senior medical officer has, from time to time, instilled into his staff certain axioms for their constant guidance. It has been, for instance, necessary that the medical officer in flying camps become, as far as possible, the confidant and adviser of all ranks. It is advisable that he himself get into the air as soon as feasible, and that the machine which carries him be put through all evolutions, in order to acquaint him with the physical phenomena of flying. No machine must leave the ground unless the medical officer on duty is within reach, nor must the latter leave the aerodrome while there is a machine in the air. A further responsibility is that he must pronounce upon the fitness of all cadets and flying officers to take the air, and, further, without hesitation, prevent any man from going up who is, in his opinion, unfit. As routine work he must also conduct a monthly physical inspection of all cadets, and be present at all “test flights.”

The psychological side of medical service takes on new proportions in a flying camp. The personality and characteristics of the patient in question must be always kept in mind so that when investigating air sickness the medical officer may determine whether it is real or assumed. The question of fear, i.e., “aerophobia,” in its actuality, and any loss of nervous control, must be established if existing—and obversely. Any excitement or tension must be carefully distinguished from natural recklessness or other characteristics of what is termed a “thrusting disposition.”

An exhaustive study of the ideal pilot established the fact that he should have an acute and correct sense of equilibrium. This does not appear so essential for an observer, who if he is fairly safe in the air and does not become giddy in stunting, may prove acceptable.

The “rotation tests,” described in detail below, have proved that as regards a great number of successful pilots—referring to those who have flown 100 hours and more,—in no case has a man been discovered who has not conformed to the above standards laid down for admission to the brigade. Above all there is demanded a sound physical condition, by which alone all bodily functions will respond normally.

The following data are taken verbatim from memoranda issued by the senior medical officer and authorized by the G.O.C. for the information of medical and flying officers:—

“For the information of the flying officer, a short explanation of the phenomena of equilibrium may not be out of place. Deep in the bones of the skull, in close connection with the hearing apparatus, lie, one set on each side, a series of three minute canals, filled with a clear fluid and lined with a membrane intimately connected by delicate nervous elements with the brain.

“These canals, each corresponding to half of the arc of a circle, are about half an inch in length, have a diameter of about one-twentieth of an inch and inter-communicate. They lie in the three dimensions or planes of space, and it is primarily due to movements in the contained fluid acting on the delicate nerve terminals, which are directly connected with the brain through fibres of the Vill nerve, that man is enabled to maintain the equilibrium of the body. It may be of interest to note at this point that the corresponding system in birds shows the extremely high degree of development one would expect. Knowing that to be a successful pilot a man must have an accurate and delicate perception of his position in relation to the earth, it is readily seen how intimately the internal ear, its adjuncts, and the problems involved in aeronautics are related. It should be understood that the canals mentioned above have nothing to do with the sense of hearing.

“Close to these, and in the same portion of the bone, lie two others closely resembling the spiral canals found in conch shells, and it is on these canals, also filled with fluid and lined with cells connected to the brain by fine nervous filaments, that we rely for our auditory impressions. It has been proved that not only dizziness, but also nausea and vomiting, all untoward symptoms frequently encountered in airmen, are closely connected with lesions or functional disturbances of the labyrinth of the auditory apparatus.

“In order to test the action of these canals, the contained fluid may be set in motion by rotating the body. This is most readily done by seating the patient in a revolving chair, and so, with the head in different planes, testing the different canals in turn. It has been found that pilots experiencing difficulty in flying, especially in maintaining equilibrium, and those who are troubled with vertigo or nausea, often show abnormal reactions, and it is for this reason that these tests are employed. These ‘rotation’ or ‘turning tests’ have been used for a considerable time in connection with diseases of the internal ear and in the diagnosis of lesions of the brain, but it is only recently, as a result of experimental work, that their application to aeronautics has been demonstrated and proved to be of practical value.

“In the ‘nystagmus test’ the applicant is first spun in the chair exactly ten times in twenty seconds, accurately checked with a stop watch. The examiner now carefully observes certain lateral, jerking movements of the eyes which normally appear, but should cease on an average in twenty-six seconds. A certain variation is allowed from the normal time, and cadets for pilots not conforming to this test should not be allowed to fly. In it the head is tilted forward to an angle of thirty degrees in order to stimulate only those canals which lie in the horizontal plane.

“In order to stimulate those canals lying in the vertical plane, ‘falling tests’ are employed. The subject is instructed to lean forward, resting his forehead on his hands which are placed on his knees, and is then turned alternately to right and left five times in ten seconds.

“Should he be rotated to the right and be ordered to sit up, he should immediately fall to the right, which is the normal reaction, but should he sit directly upright or fall to the opposite direction, a faulty functioning of these canals or of the pathways in the brain is thus demonstrated.

“‘Pointing tests’ are applied somewhat similarly. The candidate is turned ten times in ten seconds alternately to right and left, with eyes closed. He is then instructed to raise his arm and point to a fixed object, usually the examiner’s finger, of the position of which he is already aware. As a result of the dizziness produced, if he has been turned to the right, he should point to the right of the object. This ‘past-pointing’ is a normal reaction, and any considerable deviation will immediately reject the applicant. Even after the chair has stopped, the man still feels that he is turning and is endeavouring to locate the fixed point. The ‘past-pointing’ shows that he is attempting to allow or the rotary motion which he is still experiencing, though actually the chair is stationary.

“Since the more sensitive, theoretically, a man is, as shown by ‘turning tests,’ the more likely he is to be a good pilot, as he should be able to detect more accurately and early the movements of his plane without the use of his eyes. This is, however, true only to a limited degree, for we have found that as a rule the higher the nystagmus time, the more likely is the man to suffer from vertigo, nausea or vomiting in the air. On the other hand, theoretically, a man with a short period of nystagmus should be less sensitive to unpleasant, subjective sensations, and those with ‘dead labyrinths’ ought to be immune.

“The practical deduction is that in good pilots the ocular oscillations must not vary to any considerable extent, say not more than ten to twelve seconds; on the other hand the lower or shorter the time the better a man should be able to stand the violent swaying of a captive balloon, since it is this motion above all others that produces the most intense nausea and emesis. Following the above to its logical conclusion, we in practice reject men who show too high a nystagmus time, and recommend for observers, and especially for balloonists, those showing sluggish reactions.”

Failure to conform to either the pointing or falling reactions required are good and sufficient reasons to reject applicants for cadet pilots.

It is probable that to the layman much of the foregoing will be found technical and scientific, but to the investigator into the physical and psychical phenomena induced by flying, it should be of direct interest. In the medical service of the R.A.F., Canada, the value of these tests in their standardized form was first proved by their application to men who were actually unfit to fly, and the case sheets of many such are on file in that department.

Their adoption only followed after the analysis and continual checking of results obtained by tests not only upon those who desired to take to the air, but also those who, having flown, were reported by their instructors to be unfit to continue, and which showed that they were demonstrably correct, and not merely deduced from a priori assumption.

Investigations into “oxygen want,” as evidenced by drowsiness, shortness of breath, fainting, etc., at considerable altitudes, have led the authorities to supply pilots with oxygen tanks for use in high altitudes, since it is not the density of atmosphere but the dearth of oxygen which causes these distressing symptoms. An apparatus has recently been perfected by means of which, by diluting the respired air with nitrogen, it is now possible to determine accurately the altitude beyond which a pilot may fly in safety, and so it is hoped to prevent many casualties, and assist in the “classification” of airmen with reference to their flying capabilities.

Vision, which when abnormal causes headaches, dizziness, etc., should be normally stereoscopic, and the accommodation perfect in at least one eye; but while accurate color vision is considered desirable, it is not essential providing the primary colors are correctly recognized.

Amongst other tests adopted by the brigade are those giving the vital lung capacity, the expiratory force, also complemental and supplemental air, the former being the measurement of the excess capacity of the lungs over a normal intake of air, the latter that quantity of air remaining in the lungs after a normal expiration.

Excess of any nature is frowned on. Excessive tea or coffee drinking, or any semblance of nicotine poisoning at once asserts itself. The strain of instruction also produces definite phenomena, and pilots retained for this duty are limited to three and a half hours’ flying daily. These phenomena are watched for, and treated sanely and sympathetically, till the individual with all his personal variations becomes as it were a human barometer, which infallibly records the actions and reactions of the flying man’s life.

Owing to the fact that the pioneer attempt at systematic winter training, without regard to temperature, was undertaken during 1917-18 in Canada and successfully concluded during the severest weather of many years, certain new problems required solution. When it is realized that machines flew at ground temperatures as low as -35 degrees Fah., the occurrence of frostbite and any effect of the intense cold on the mental faculties, to the extent of producing drowsiness and even stupor, was extremely infrequent. The flying clothing provided, the Hawker boots, the gauntlets and chamois face masks, which were adopted after all ointments, oils, etc., generally in use in altitude flying, froze in situ, most effectually prevented the expected difficulties, so completely indeed that during the whole winter season no serious casualties could be traced to the effect of the low temperatures encountered.

Such in brief outline are some of the major investigations peculiar to the duties of the medical staff of the brigade. To these are of course added others better known, such as blood pressure, etc. Couple them with psycho-mental problems, and they give some suggestion of the history compiled for every would-be pilot and observer, an intimate history unapproached in detail and interest by any other tabulation of personal phenomena.

In conclusion, it is desired that special acknowledgment be made of the exceptional service rendered by medical officers on the aerodromes, and by the staff of medical orderlies distributed through the brigade.

The hours of the former were long and arduous, the duties of the latter, for which they were trained by the senior medical officer and his staff, were manifold and pressing. That they were admirably performed is of common knowledge, but that their swiftness in succour and skill in first aid saved many a life, is known only to those who have been privileged to see them at work.