SCIENCE WITH GUNS

Ashburton Guardian, Volume 61, Issue 251, 5 August 1941, Page 8

SCIENCE WITH GUNS

BRlltiSH ANTI-AIRCRAFT FIRE. .W-.G-'Uu ; INDIAN JOURNALIST’S ACCOUNT.. Rehind the anti-aircraft guns, known as Aktak in the Army, is a combination of science and skill which has had a tremenclpps influence in keeping the GermSKitiraiders off their targets, and in addingrNazi bombers to the collections of, .scrap- .metal dotted over the British ■ countryside. >. / . Describing an anti-aircraft battery in oictionaat night, Mr T. A. Raman, a well-known Indian journalist, men- . tions the -mechanical aids to accuracy operated by the crews. During a night raid he saw a group of men round what looked like an oversize camera. This was the delicate “predictor.” Some littlei distance: away three men worked the sound-locator, a weird instrument with huge trumpet-like appendages. A pause, and then came word from theicontrol room: “Target from the south-west.” Other messages came from the sound locator and from elsewhere: “Height twenty .thousand feet.” This is repeated by the man at the predictor; Height, speed and other’data were fed into the machine. t 4?Fire,’ ? -'-said a man at the predictor. “Eire,” j bellowed the sergeant. A terrific flash lit the meadow and the battery: was in action. -The':key instrument says Mr Raman, is thO predictor, a thing of marvellous sensibility, >’ worked by experts but ir-

reverently called “the sausage mach-

irie’T;' or even “that there sausage thihgi”'A miracle of speed and accuracy,;;it: takes the data it is given, allows

for-thewind and the weight of the shells and' other ballistic factors, and gives a series of positions for the plane. ■lt works out, too, the seconds it would 1 take the shell to reach the objective/ a- most important factor, because heavy anti-aircraft guns fire shells which explode either on contact or at a set time. The machine works with its own “eyes” in daytime, or with 1 the ( searchlights at night. Other wise it gets its data from the sound locators.

• “In a pause between the rounds, the second officer takes me to his machine. Thomas, ex-piano tuner from Lambeth way,.-is the key man. He sits among the 'trumpets,’ with two colleagues at lower levels all ear-phoned, and watching flickering light rays in instruments before them. Three men gently rotate tlib tfirntable ; as and how they are directed. , / -

“Talking is sotte voce and every move stealthy, for small local noises might get mixed up with the sound of far-away engines. Thomas and his men feel'-round space till they are ‘dead on,’ and then flash the message to the predictor giving the bearings. “We go down to the control room. There is an almost scholastic atmosphere here that is, if you omit the uttscHpiastie Jokes and asides. A goodhumoured mail with a pipe in his mouth sits with ear-phones in one corner:'-' : -v’- ■

“All- the time he keeps jotting data on pieces of. paper, and passing them oii f 6' r his/companion, A jovial youth, who 1 sits Avith .a large map of London before liiiff;' 1. Over the map is a trapssheet, and on this he pictures in arrows’ the data he is receiving. see the arroAvs pointing at us ilroin different -directions. They move %earer and one takes a leap to Avithin ouivgun. range, and the Avord is passed approaching.’ -Some come -'-quite close and glance aAvay at the last -second. Others suddenly turn tail and 7 'a're mopped off the map.

oi OThe commanding officer is busy W/ith .a graph of curves and with hooks ' & df ; -figures. He is copying some figures ‘into another book and making some "quick calculations. ‘Working out a barrage,’ he explains, and tries to tell me ’-'-how exactly it is done.” W' Anti-aircraft firing is not taking poti/luckfin the stratosphere. With the most -'afecufate calculation it is still a chancy flhisiness, -and all the time efforts are Uiiiade to reduce tho margin of error, v Each shot is timed and predetermined, based on an array of calculation. Every : "-shell goes out with a good prospect of meeting its target. ••; -••■■lt is this excellent ground work, this "-qhick reckoning of maximum probabr <: ility' that extracted from the German the Unwilling praise that the “British anti-aircraft, fire was unbelievably accurate.” JJW-V -