Arizona republican., 1917-06-27
NEN NCUNFOUND FQR. h|RPLANES
 E NON- -RECOIL

Up to the present time it has been found impracticable to arm airplanes even those of the largest type with any weapon heavier than a ma chine gun or bomb or. in a few cases. with a 1-pounder gun of low muzzle velocity. The difficulty of mounting guns of heavier caliber on airplanes mas consisted not so much in the great v-aight to bn carried as in the fact that it has been found impossible to provide for the shack of recoil.
 According to an illustrated article in a recent number of the Scientific American supplement, however, it would seem that this difficulty has now been overcome by the develop ment of a gun of non-recOil type for airplanes. With the perfection of this weapon the six of the gun to be car ried is apparently limited only by the capacity of the aircraft-and airplanes are now in use which are capable of carrying guns of and S-inch caliber. It would be hard to oVerestimate the importance of this invention. Equip ped with this gun,' says the article iu question, the airplane will indeed become a more powerful instrument of warfare than the dreadnought of today"
 The unmiIitary reader will perhaps grasp something of the significance of the above announcement when it is realized that the standard gun of the United States field artillery is a 3-inch rapid fire rifle-the famous "75" of the French army. A 6-inch gun comes under the classification of siege guns.
 The basic principle of the new guns which renders it adaptable to aircraft is double ended" construction. It is in effect, two guns placed breech to breech and fired simultaneously to the front and to the rear. Thus. the recoil on one gun takes up that of the other, with a complete balance of forces and an absence of heavy shock. The two barrels are joined with an interrupted screw tread so arranged that d single motion of lever unscrews the rear members and swings it downward and to the right in the position for eject ing the empty shell and reloading. The front barrel is rifled as in land weapons of the same type; the rear barrel for the 'recoil' charge, is of smooth bore. The chamber for the shell itself is, of course. of unidue construction. At the front end of the case is the proiectile. as in ordinary shells. in the middle the firing charge and in the rear the recoil charge of fine lead 9hot. Upon discharge the lat ter. which necessarily equals tho weight of the front proiectile, breaks up and loses it's velocity in few yards and so is not menace to anyone behind or below.
 To the layman's eye and from a casual gance the non-recoil gun might be mistaken for some form of tele- scope mounted on a pivot. Its marked feature is slenderness and lack of ta.,1I- se sr11 c-it1 .1n in a0r1 struction and operation and it's weight is decreased to a minimum by the use of special alloy steel of high elastic limit.
 The writer observes that certain re- gently constructed airplanes have a weight carrying capacity of about one and one-half tons, exclusive of fuel and pilots. This is well in excess of the weight of the 6-inch non-recoil gun with Q liberal supply of amnu- milton.
 Guns fired from the surface of the earth the article concludes, "can ob- tain comparatively long ranges only by being fired at a high angle of ele- vation, so that the projectle at ap- proXimately the middle point of it's flight attains a considerable altitude. The airplane gun. on the other hand starts it's projectile from q compara : lively great altitude, and as con- sequence has correspondingiy great CT range. or an equal range with a much lower initial velocity. Not only is there an advantage fin the form ol long range hitting, due to the higf altitude but there is also concur ent advantage due to the action o1 gravity. There is a great amount ol potential energy stored in a projectilt when fired from an altitude of severa thousand feet and this energy i utilized to a certain extent in over coming the resistance of the atmo sphere''
 The non-recoil gun is an American invention and, it is stated, has alread, hAer manlfa cured in large number in this country.