ON AIR "STUNTS"

Dominion, Volume 11, Issue 183, 23 April 1918, Page 5

ON AIR "STUNTS"

INTERESTING GOSSIP ON 'PLANE

TECHNIQUE

STALLS AND SIDE-SLIPS

(Bv an Officer i f Hie -Royal. Flying Corps.)

[Published bv authority of tho War Office, per favour of the Royal Colonial Institute.]

"When the war in tho ;!Hr assumes tho proportions tho •■sports would havq us anticipate, wo may expect the official nvintion conimuiiiri'ues to read something like an admiral's report of a fleet action. Most of us are acquainted with the breezy laiigiingo of our (lying men, a sort of luotoring-cum-nautical jargon, rather unintelligible to tho layman; but apart from tho slang used by airmen in describing their eteeds niul deeds, many neronautical words and phrases have crept into tho newspapers and magazines which aro all Greek to tho landsman. One's daily work in tho Flying Corps is spoken of as a. mixture of "zooms, sideslips, and vertical banks and gusts," all intended to put "Archie" off tho mark, followed by "stalling and nose-diving, and sitting on somebody's tail," finishing up with something being "sent down out of control in a spinning nose-divo to crash, thousands of feet below"—regarded collectively as a "good stunt." Let us analyso some of theso aeronautical terms.

"Taxies," "Zooms," and "Stalling." When beginning a flight a pilot usually "taxies" his machine from outside the hangars to a position on tho aerodrome before "taking oft'." To "taxi" is to move forward over the ground on the undercarriage wheels with less power than is seeded for flight, i.e., with the motor only partly working. "Taking off" is the initial run across the aerodrome with engine "all out," in tho process of getting iip flying speed before leaving the ground. The next' manoeuvre for some pilots would bo a "zoom." To "zoom" 'means to accelerate speed by a divo with full engine power, and then to swing upwards until the momentuhi is. spent —a glorified switchback. It is usually performed as a showy sort of departure, especially if tJio_ passenger seat is occupied by one Who is about to ' enjoy his first flight. It produces the ■kind of feeling one experiences in a lift, going down suddenly. This manoeuvre introduces us to a "stall," or position ■ which results from loss of flying 6pecd. There is a minimum forward speed cap- . able of holding an aeroplane in the air, and in "stalling" the nose of tho machine is held up at 60 great an anjlo from the horizontal that forward movement , ceases, and the supporting power of the wings is lost. The forco of gravity asserts itsolf, and this the engine is unable to, overcome. • • ■-. , • • ■ We now propeed to'"get height." The . greatest altitude we can reach,is known a3 the aeroplane's "ceiling." AH machines have a limit tis .to the height to .which they can ascend., Being over the lines on "patrol duty" we "sit" over a certain rfrea, waiting for a "black-crossed Hun-bird." Having spotted our quarry we "dive" to the attack. This "diving" business 19 accomplished by operating the controls so that tne elevating plane hinged to the tail is drawn down, resulting in the tail being blown up. The controls are held in this position and the machine gathers down momentum. Our forward fixed machine-gun, firing through the airscrew, is trained on the enemy, and the pilot "sprays" his bill-, lets at the target by waggling tho rudder bars, making our downward course a zig-zag one; the mauliine-enn being.on a fixed mounting the bullets traverse right and left accordingly. Having shot away some vital part of the German machine, the latter is said to have been "sent down out of control."

"Sitting on His Tail." We.now spot another German machine making for our. side of the lines, and endeavour to attack him from a "blind spot" behind; so proceed to "sit on" or "under his tail," from which point, we can rake him,with our forward guns while ho in turn is prevented from replying, having no field or fire immediately astern cwing to the obstruction caused by his own tail. The German pilot" evidently has been shot, as he falls forward on to Qiis controls, and, with engine full on, commences to go dowtf|in a "spinning nosedive." This l's literally coming down nose first in a whirlpool, revolving -with cver-increasing sp.eed with one wmg-tip as a pivot, the sort of thing which hap.pens vrheix a machine gets out of control, It is part of an airman's training nowa> days to put his machine into this attitude and "spin".down a few thousand feet and finally. recover equilibrium. Many a pilot has saved himself when attacked by overwhelming ? nunibers by feigning "out of action." Elsewhere in the sky wo can see a duel in which tho combatants are jockeying for position by "looping," "Irainelmann turning" (a sort .of half-loop which is the quickest way of . doubling back on one's tracks, during which the machine seems to roll over on its back), and other aerial acrobatics —"acrobatics" in the language of 'the text-books, "6tunts" ■in the language of the aimen. While recrossing the lines on the way home we ars severely "Archied," i.e., fired at by anti-aircraft guns, from whose attention wo only escape by a series of "side-slips" or "skids in tho air," "outward side-slips" being effected by using "rudder" with no corresponding "bank," "inward side-slip" being produced by use of "bank" and no "rudder," causing the machine to slip earthwards sideways. These aro much-used manoeuvres to escape the attentions of "Archies" and searchlights, as -the apparent direction of tho machino is unchanged, its noso still pointing ahead while height and distance aro lost by tho .deception. Getting Home. Having arrived over tho spot -where we ■wish to land, tho pilot shuts off his motor and commences to "volplane" or "glide" down, relieving tho monotony by a '•'corkscrew 6piral" and "tail-slide." Tho "corkscrew spiral" is just what its nanus implies, descending with the wings .vertical and turning about a central vertical axis, a tideways loop, holding to tho coureo by contrifugal force. In this "stunt" tho fuuetions of the rudder and clovator controls are reversed, the clevai tor acts as a rudder, and vice-versa. The ."tail-slide" is simply slipping backwards from tho "stalling-point" tail first until the machino rights itself. 'Having to land in an aerodromo restricted to sizo, an "active service landing"' is. accomplished; i.e., tho slowest landing possible, in which the machine does not roll or run distance after the wheels touch tho ground. In fact, the machine is "stalled" as near the ground as possible, the last foot or so, tail well down.