FlightGlobal.com
Home
Premium
Archive
Video
Images
Forum
Atlas
Blogs
Jobs
Shop
RSS
Email Newsletters
You are in:
Home
Aviation History
1917
1917 - 0086.PDF
I/LIGHT JANUARY 2j, 1917. HOW GERMAN PILOTS FIRE "THROUGH" THE idea of firing a machine gun between the blades of apropeller in motion, generally admitted to have originated with. Mons. Garros, the famous French aviator, has by nowbecome very extensively adopted by the aviators of all the belligerent nations. While the French method, by which theportion of" the propeller blade that comes in line with the trajectory 13 armoured to protect it from damage, is generallyknown over here, the much more elaborate system said to be used on some of the German machines is, perhaps, not^sowidely known. Early in 1915 we recorded in " FLIGHT " that a German inventof hadpatented an arrangement by which firing of the machine gun was prevented at theinstant when a propeller blade was in line with the gun. The general arrangement ofthis " fire interrupter," as we shall call it for want of a better name, is illustratedand described as follows by our contem- porary. Scientific American :— " The first move of the Fokker pilot afterengaging with an enemy airman is to settle on a certain plane of flight andthen lock the elevator control by means of lever A, so that he can then steer toright or left by the action of his feet On the rudder bar and maintain lateral balance by moving the control post with his knees ;but he must continue the flight in the same plane until the elevator is %gain freed.This procedure permits the airman to use his hands, since they are no longer required•n the handle bars. " The machine gun of the Fokker is of the Maxim type, and is immovably affixed above the engine cowl and slightly to theright, so that its line of fire passes through the path of the revolving propeller in front.In sighting his gun the pilot, as previously stated, manceuvers his aeroplane until thesights register on the target. This task calls for a high degree of skill, for boththe firing medium and the target are mobile, while the steering of an aeroplane is accom-plished by relatively slow movements of considerable amplitude." Instead of the machine gun being fired by pulling the trigger, as in usual practice,the trigger is operated by a cam and transmission mechanism under the controlof the pilot. On the revolving shaft of the rotary engine is a disc carrying a slightbulge at one point whose relation is at right angles to that of either propeller blade. The disc isindicated at B, while upon it rests a small wheel, C, which receives the reciprocating movement brought about by the IS 13 Women for Aero-Engineering WorkTHE Ministry of Munitions is extending its plans foi the employment of women on engineering work. Classes fortraining in setting-up and skilled operating on various types •f machines are being held in' London, and the Ministryappeals to women of good education and physique, between 20 and 35 years of age, to undertake the training. Thecourse will last from eight to nine weeks. Maintenance grants will be paid during this period, and those who becomefully proficient for service in aero-engine or other munition works may expect a minimum wage of £2 per week. Candi-dates must be prepared to accept employment in any factory to which they may be sent on the completion of their train-ing, and to work during the usual factory hours. Applica- tion, in writing, giving particulars as to age, educationalqualifications, and previous mechanical experience (if any), should be made to the Ministry of Munitions (TrainingDepartment), 6, Whitehall Gardens. British-Made Magnetos on Top. I HE perfection of the high-speed internal-combustionengine which began with the introduction of the motor car 21 years ago has remodelled our methods of traction and atthe same time created a vast industry, with a large number of contributory trades more or less dependent on it. THE PROPELLER. use of the cam member. The reciprocating movement istransmitted by a sys'tem of levers and springs, D, finally terminating in the piece E, which is hinged as shown.Normally, when the gun is not firing, the piece E is raised so that the reciprocating movement ends with it; but atthe moment the pilot is ready to fire the gun he presses a small lever, H, fixed in the centre of the steering bar control,which, by means of the Bowdea wire G, causes the piece E to be brought down in line with, and to act upon, piece F.The latter acts directly upon the trigger of the gun. " The action of the firing mechanism is to pull the triggerof the gun once for every revolution of the engine and pro- peller, at the moment when neither of the two propellerblades is in the line of fire, in spite of the high rate of revolu- Diagrammatic drawing of the arrangement by which German aviators fire their machine-gun between theblades of a revolving propeller. tion of the propeller which normally reaches some 1,200 r.p.m.or 20 revolutions per second. Since the average machine gun fires anywhere from 400 to 600 rounds per minute, or 6 to 10per second, the opportunity to fire 20 times each second is ample for the proper functioning of the gun when the engineis turning over at the usual speed. The cartridges are fed into the gun from the belt magazine J, the empty shells areejected through the tube I, which passes through the wall of the fuselage, while the empty_belts are deposited in thecontainer K." Among the most important of these may be classed themanufacture of magnetos. But when war broke out there was only one British firm making magnetos, its output being undera hundred a week. Practically every magneto which went on to the motor vehicles, motor boats and aircraft of GreatBritain came from enemy Germany or from America. Till August, 1914, we had been content to go abroad for nearlyall our magnetos. But in a few short months British manufacturers gotsteadily to work. Some of the best scientific brains in this country were enlisted. New and special steels and othermaterials were evolved. To-day there are some 12 or more British firms making magnetos. Their entire outputs, so we now are officially informed,reaching a total to date of over 165,000 magnetos, have been made for war purposes, and are used on aeroplanes, sea-planes, airships, motor lorries, motor ambulances, motor cycles, " Tanks," big gun tractors, motor boats, wireless sets,searchlight sets, lighting sets, &c, &c. In fact, it may be said that the war is being conducted on British-made mag-netos. After the war the resources of the British magneto manu-facturers will be at the disposal of the British public. There will bs no need to buy enemy or other foreign magnetos. 86
Sign up to
Flight Digital Magazine
Flight Print Magazine
Airline Business Magazine
E-newsletters
RSS
Events
