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: .JI I

NOVEMBER-DECEMBER,193~

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4. TITLE AND SUBTITLE The Coast Artillery Journal. Volume 82, Number 6, November-December 1939

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7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) Coast Artillery Training Center,Coast Artillery Journal,Fort Monroe,VA,23651

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INSTRUCTION

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GUNNERS'oH ~_ •• _ •• - K<

:t:'IS

rCOAST ARTILLERYJOURNAL

FOUNDED IN 1892 AS THE JOURNAL OF THE UNITED STATESARTILLERY

MAJOR AARON BRADSHA \'V', JR., Editor

. VOLUME LXXXII NOVEMBER-DECEMBER,1939

CONTENTS

*

NUMBER 6

COVER DESIGN: "Rel1olutionary Cbristmas." By Hobart Britton

FRONTISPIECE: "Hampden Bombers 0 Iler London" 498

GERMAN AA ARTILLERY TODAY. By Major Caesar R. Roberts 499

THE NEW' DIVISION. By Lieutenant Colonel Harry C. Ingles 511

SEEIN' IS BELIEVIN'. By Captain Edward Barber 520

LITTLE PHIL - Part II. By Fletcber Pratt 530

TROOP SCHOOLS IN THE COAST ARTILLERY CORPS. By Major Coburll L. Berry 543

THE GERMAN CAMPAIGN IN POLAND. By Lieutentlnt Colonel 1'011 Wedel 546

CAMPAIGN IN POLAND: Pictures 552

IDENTIFICATION OF CAMERA FILMS. By Sergeant H. E. DeFlorin 558

SUGGESTED SERVICE OF THE PIECE, 37-M~L GUN. By Captain J. E, Reierson 561THE RECRUIT AND HIS ARMY. By Lieutenant C. Robert Bard 564

THE 621s( WINS TROPHY 566

STORY OF ARTILLERY THROUGH THE AGES. By JlI', A. Windas 569

NE\X'S AND COMMENT 570

COAST ARTILLERY BOARD NOTES 576

COAST ARTILLERY ACTIVITIES 581

THE ANNUAL CONVENTION , 597

COAST ARTILLERY ORDERS , 598

THE CONTRIBUTORS , 599

BOOK REVIE\X'S , 600

INDEX, 1939 607

PUBLICATION DATE: DECEMBER 1, 1939

[Opinions expressed and conclusions drawn in articles are solely those ofJ

the authors and are in no sense official. Thev should not be considered asthose of the Chief of Coast Artillery or any b~anch of the War Department.

Published hi-monthl'\'" b~ the enited States Coast Artillery Association. Editorial and executh"e offices, 1115 Seventeenth Street, X.\V.,""all.hingtoD, D. C. -Terms: $4.00 per year. (Coast Artiller~t Association members, $3.00 per year.) Single copies, 75c. Entered as second-dass matter at Washington. D. C.; additional entry at Richmond, Va., under the Act of ~Iarch 3. 1879. Copyright. 1939. by the United

~M~ rf)a~t Artillerv Association.

By Major Caesar R. Roberts, Coast Artillery Corps

Be at tf1e 'ti9ltt place at tf1e'ti9ltt tim.e; open ti'te m tf1e

~lto-1te&tpo~~ible tim.e

A well known military axiom tells us that man hasalw3Ysdeveloped a mean~ to counter every new offensiveweapon. It is not surprising, then, to find that the earliestrecorded endeavor to use aircraft for military purposes al-lllOStsimultaneously brought forth the very first antiairweapon.

During the siege of Paris in 1870' the beleagured Frenchllsed free balloons to carry passengers and mail from thecit\. and over the lines of the surrounding German forces.TI;is had gone on but a short time before the famousKrupp works at Essen built and sent to the German Arm}'five "balloon cannon." On the 12th day of November,1870, one of the new Krupp guns actu~lly shot down aFrench balloon that essa}'ed a sortie from the capital, andso for the time being summarily ended further attemptsat .Iir warfare. One of these weapons is still on exhibitionin an arsenal museum in Berlin.

For a long time both the idea of aerial warfare andmoves to counter it were laughed off. But at the turn of thecelltur." the appearance of a French dirigible and the laterSllccessof Count Zeppelin with his airships brought Ger-lllan studies to determine whether a foot or field artilleryweapon was best suited to fight motor balloons. The re-sults of the 1910 Kaiser wfaneuvers and some specialfirings over the East Sea brought home the realization thata special weap::m was needed to fill the role. The develop-ment of such a weaponwas undertaken butfor 'luite a while f1rinO"• :->Instruction was con-fined to theory becauseno practicable t:1rgetsWere available. H~w-ever, the outbreak of.he war in 1914 foundIII Germany someeighteen cannon de-signed for defense

against balloons. At first attached to arm}' corps. theywere soon withdrawn for the defense of the bridaes and

:>airship hangars at Dusseldorf and Friedrichshafen, as wellas the gasworks in Kaln. And it was only a short timebefore ~here arose a great demand for mor'e and more ofthese weapons.

Nonetheless, the needs of the foot and field artillerytook precedence, so as a temporary measure capturedFrench and Russian gun:;, for which ammunition wasavailable, were improvised for this new defense. By thespring of 1915 there were some 200 balloon defens~ can-non-called Bak-and it was at this time that the firstattempts were made to collate and study the practicalknowledge and experience gained in ground defenseagainst aircraft, from all over the Western front. As aresult, a special service for this new field of combat wasorganized on July 10, 1915. But it was not until almost ayear later that this new service received the name by whichit is known today, Lhat is, Flak Artillery. The word comesfrom the first letters of Flug-A bwehr-Kannonen; Fluf!. forFlugzeuf!" meaning airplane; abwehr, for defense, al~d ofcourse Kannonen for cannon.

It was soon realized that a new weapon with longerrange, larger caliber, shorter time of flight and improvedlaying apparatus was absolutely essential. Because of thetremendous overload that the war industries were carry-

in?;, it was a year and ahalf before a weaponconsidered superior tothose of the enemywas delivered at thefront. A director, call-ed Kommar.doaerai,

b

was developed andsixt\, of these reachedthe' front before theArmistice. Night at-tacks became a source

L

500 THE COAST ARTILLERY JOURNAL N ol'ember- December

8.8-C111.Flak towed b)' medium crosS-colmtr)' I'ebide.

Total 1,588 planes 2 airships 341 planes

The Allies apparently realized the effectiveness of theGerman AA artillery, for the Treaty of Versailles forbade

this new weapon in the Reich's military forces, with thebare exception of a few pieces in the fixed defenses of Fon 'Koenigsburg. Owing to a strange oversight the GermanNavy was able to carryon development, and a great dealwas accomplished, especially with the small caliber weap-ons and the range-finding apparatus.

But no treaty, however severe, was able to prevent theGerman mind from studying antiaircraft defense. N10re-over, their military students took advantage of the successor failures of other nations in development. When compli-mented on the great progress that has been made in 50brief a time, it is not surprising to have Flak artillery of-ficers answer that during the past years the best brainsand talent of the nation were working with them on their

problems. BASICORGANIZATJON

The combined armed forces of the nation arc known asDie IVehrmacht, composed of the Army (Heer), theNavy (K riegsmarine) and the Air Force (Die Luft-waffe). The latter came into official existence on wlarch I, I1935, It is composed of: Flying units, called Die Flieger- Itruppe; Air intelligence units, or Luftnachrichtentruppe;and the Flak artillery.

Fairly recent figures on the personnel strengths of thethree subdivisions of the Luftwaffe gave the flying corpsabout forty-five per cent, the air intelligence troops aboutfifteen per cent, and the Flak artillery the remaining fortyper cent of the total strength.

Before the enlargement of the Reich through the recentannexations, there were seven :tir districts throughout theland, each under the command of a general officer.

The Flyino Units. Usuallv listed first are the observ;1-o /tion or reconnaissance elements, some of which are at- ,tached to army corps when the latter take the field, andperform the customary duties. Those that remain withthe Air Force proper perform similar though Ion getdistance missions. It is pointed out that their mission isto obtain and bring or send back information, that theyare to avoid combat, and may be expected to A:' singlyand at high altitudes.

SHOT DOWNBYGerman Flak British A A

51 planes 1 airship 20 planes322 planes I airship 50 planes467 planes 95 planes748 planes 176 planes

Year1915191619171918(10 mos.)

of worry, and the searchlights, formerly operated by thepioneers were taken over by the Flak service in July, 1917'Special schools were soon organized, one being set up be-hind the Flanders front. It is interesting to note that one ofthe ven' first of the instructional staff was a First Lieuten-ant Rudel, today General of the Flak Artillerie and chiefof all air defense.

A range-finder's school, finally capable of instructing1,200 men in range-finding, lead computing and airplaneidentification was established at La Fere as earlv as Julv,1915; the school later moved to Ghent. A ;chool f~rmotor transport-within the service-was set up atValenciennes in April, 1917; a searchlight school. at Han-over, and finally a school in Brussels for the airplane re-porting service, as well as a small military-technicalacaden1\'.

It wa~ on the 8th of October, 1916 that this service defi-nitely became part of the German Air Corps, and Generalvan Hoepner was placed at its head.

The end of the war saw some 2,210 heavy Flak weaponsand about 356 light Flaks in service at the from or in reararea defenses. Only about an eighth of these were con-sidered worthwhile weapons, and only a tenth wereequipped with directors. The Germans point with no littlepride to the accomplishments of the new arm. Casualtiescounted were airplanes or airships definitely shot down,and of those forced down, only the ones landing behindGerman lines. Hauptman ?vfatthey gives the followingcomparison of German and British losses from antiaircraftfires:

-1939 GERMAN AA ARTILLERY TODAY 501

Bombing planes 3re divided into two distinct cbsses.TIle first is the powerful, multimotored, long r3nge t~'pe,while the second is the dive bomber, reserved for objectivesdem3nding 3 high degree of bombing 3CCur3CY; thesebtter 3re manned b~' speci311y selected 3nd tr3ined pilots.Three pbnes form 3 Kette. The b3sic unit is, however.the StafJel, consisting of nine planes. Three StafJeln con-stirute 3 GTI/ppe, 3nd three Gruppen make up 3 Gesch-wader of some eighty-one pbnes in 311. H3uptm3n Neu-man says that bv dav the bombers move to the 3tt3ck inGrsch;;ader uni~s ..

The pursuit element is known 3S the lagdflieger.Schilfbrth 3nd S3chs state d13t thev willusuallv be foundworking in cooper3tion with the Ffak 3rtiller~'. ~re of highspeed, but of compar3tively short r3nge. Att3ck 3irpbnesas such 3re not mcntioned. Se3pbnes 3rc divided into thcvarious cbsses to which we 3rc 3ccustomed.

The Air Intelligence Troops 3re org3nizcd I!lto com-pames:

Telephone operatingT elerype oper3tingT elcphone constructionR3dioR3dio be3con, andAirpbne reporting

Thc comp3nies m3)' bc groupcd into b3ttalions 3ndregimcnts 3S desired. In gener31, units 3re motorizcd. Thctask of these troops is to oper3te 3nd m3int3in 311com-munic3tion me3ns. Thcir duties 3re considcrcd of greatimport 3nd the outcome of b3tdes will bc grc:ltl~, influ-enccd b)' thc manner in which thc)' perform.

THE FLAK ARTILLERY

The missions of the 3rtillerv 3re ~ssentiallv those statedin our own C03St Artillerv Field j\1 anual, but it is inter-esting to note that Schilff3rth and S3chs point out thatFbk 3rtillerv C3n C3rtT out its task onlv when an efficient3irplane rep~rting scr~'ice gives timel~' 'warning of the 3p-proach of ever)' enem~' 3irpbne.

The basic units 3re thc .1bteilungen or batt3lions. Theheavy battalion, corresponding to our gun battalion, iscomposed of:

A staff battery, including 3 metcorological section,3 gun batterics, manning four 8.8-cm. guns each,A light b3tter)', m3nning six 2.o-cm. Fbks,' andA searchlight b3tter)', oper3ting nine Iso-cm. lights.

The unit is apparentl~, 3 tr3ining rather dun a tacticalgrouping. In the field, the six- 2.o-cm. Fbks are dividedup among thc gun batteries, two to cach battery.

A light Fbk b3ttalion thc writer visited at Brandenburgwas composcd of the usu31 staff batter)', thrcc firing b3t-tcrics manning twelve 2.0-cm. Fbks each and a scarch-light battcry m3nning twelve 60-CIll. lights. It W3Sstatedthat a 3-7-cm. battcr)' W3Sto bc 3dded to the org3nizationas soon as thc equipmcnt bec3mc 3V3ibblc.

Vcr)' little mcntion of machine guns is found in booksdealing with Fbk artiller~' although there 3re some AAm3chine-gun comp3nies. Thcse 3re ncarl)' alw3)'s foundin the fixed defcnses and are not norm311)' equipped withmotor vchicles. Scveral machine-gun sections are com-bined into 3 comp3n)' and commanded b)' 3 capt3in.

'In the fall of 1935. this light battery manned 3.7-cm. guns butSchil ffarth and Sachs in 1938 sho\\' each heavy battery to havet\\'o 2.0-cm. FIaks. It \\'as understood that these light weapons aregrouped together as a battery for training purposes only.

"Prepare for aeliol1!" B.8-em. Flak.

THE COAST ARTILLERY JOURNAL502

3.7-011. Flak

THE LIGHT FLAK

One of the most interesting :lI1d important develop-ments in antiaircraft artillery is the intermediate caliberweapon. In the German ar~illery there are two distincttypes in service, the 2.0-cm. and the 3.7-em. guns.

The 2.0-cm. aun is the more recent of the small caliber~weapons. It is carried on two wheels and towed by a truck.In traveling position with accessories it weighs some 1,5°0pounds. An ammunition clip holds twenty rounds, eachcartridge weighing about 10~ oz. \Vith the well knownsuper-sensitive fuze, a round flred from a distance of 150meters at two pieces of cardboard, 2-mm. thick, spacedtwenty centimeters apart., penetrated the first piece witha clean hole, and exploded before reaching the secondpiece. Fired at a meteorological sounding balloon, theround exploded within the balloon. Fired at an airplanewina it burst between the surfaces, comfJledv shattering

t)' .I .. J

the structure.The shell is self-destroying after a flight of ). 5 seconds

or about 2,100 meters range. Without the self-destroyingelement, the range is given as 4>4°° meters. The muzzlevelocity of the weapon is 900 meters per second. Theweapon's effectiveness well overlaps the minimum effec-tive ranges of the heavy Flak.

The secret of the success that has been obtained withthis weapon and the 3.7-cm. Flak-as demonstrated inSpain-is to be attributed to the hre control sight usedwith the individual piece. The sight, known as the Flak-visier 35, is of the reflecting-mirror type, with a data calcu-bting mechanism. A model similar to this one in princi-ple, was described in "Zeiss wfachine-Gun Sight" byMajor \Villiam R. Sackville, CA.C, in the November-December, 1937 issue of the COAST ARTILLERYJOURNAL.

3.7-clII. Flak read)' to fire tr0111 wheels.

The sight has a knob at its base which an operatorpoints parallel to the direction of the target's Hight. Thegun comm:lI1der estimates the ground speed of the target:Illd calls it to the operator, who sets the valve on one ofthe disks. The stereoscopic range reader furnishes the slantrange, which is also set in. The necessar:; leads are auto-matically furnished the gun pointer.

Though the rated firing speed is 280 rounds per minute,the rate actually obtained is about I 10- 120. Only two orthree rounds :tr'e hred at a time, the piece being 'carefullylaid for each burst.

The value of the sight depends, of course, on the skillof the operator, and on the ranges furnished. Each guncrew has a stereoscopic range reader, equipped with theEm 1 mR range finder (I -n1. base), with which he is ableto read ranges from a minimum of 250 meters up to 8,000meters. During a drill that the writer witnessed, the rangereader called off the slant ranges in even hundreds ofyards every several seconds. Great stress is laid on the train-'ing of th:se operators.

In an emergency, the piece m:t)' be fired from thewheels, :tbout thirty seconds :tErer the order is given.Ordinarily it takes :tbout two minutes to put it down inthe normal hring position. It may be dismantled and putin firing position on roof-tops, bridge piers, :tnd so on.

There arc two models of the 3. 7-cm. Flak. The principaldifference seems to be in the mounting of the weapon. Theheavier and older type, called the 3, 7-cm. Flak 18 iscarried on two bogie trucks, while the newer 3.7-cm. Flak36 is mounted on one axle. Though rated as hring 150shots a minute, the expected rate is from sixty to seventyaimed shots per minute. The complete round weighs 1.5kgs. and there are six rounds to a clip.

The maximum range of the piece is given :ts 8,000meters. The projectile ordinarily has the self-destroyingdevice which functions in ten to fourteen seconds at about3,600 to 4,200 meters. A hre cont;ol sight similar in prin-ciple to the Flakvisier 35 is used on the 3.7-cm. gun, andeach crew has its stereoscopic range reader with theEm 1 mR apparatus.

The 2.0-cm. batteries are organized with four hringsections of three guns each, while the 3. 7-cm. units havebut three hring sections of three guns each.'

'In the fall oi 1935 the Z.O-cm. units were organized into threefirin~ sections with iour guns each. The pres~nt setup is takenirol11 Schilffarth and Sachs. edition oi ~rarch. 1938.

1939 GERMAN AA ARTILLERY TODAY 503

3.7-C111. (Model IS) Flak in firillg positioll. Range reader at left.

504 THE COAST ARTILLERY JOURNAL Noz'ember -December

The 2.o-cm. battery has five small radio cars, equippedwith two-way voice transmission sets, working on highfrequencies, with a range of six or seven kilometers. Thereis also a larger radio truck equipped with a more powerfulset. The 3'7-cm. battery has a smaller amount of radioequipment.

With each of the light batteries in the field, there is aplatoon of four of the small searchlight units. These smalllights have mirrors of a diameter of 6o-cm.-just undertwenty-four inches-and are powered by an eight kilowattplant, carried normally in the towing truck. Sound locatorsare not used with the small lights.

THE HEAVY FLAK

The heavy cannon has a caliber of 8.8-cm., a barrellength of 56 calibers, rated muzzle velocity of 820 metersper second, and can be traversed through 3600 and ele-vated at 850. The azimuth and elevation handwheelshave a slow and a fast speed of operation. The rate of fireis from fifteen to twenty rounds per minute. It is under-stood that a heavier cannon is contemplated but no detailsof this weapon are at hand.

Two of the four cross-arms that support the piece in thefiring position together form a stout truss with the baseof the mount at its center. In the traveling position, thetruss ends are carried by the front and rear truck bogies.The other two cross-arms, at right angles to the truss, foldup vertically in the traveling position. Two cables, heavyhammers, picks and shovels are carried on the front bogies,while the telephones and fire control cables are on drumsmounted on the rear bogies.

Because of the closeness of the gun trunnions to theground and the weight of the round, a loading tray andautomatic rammer are provided. The latter is poweredby a spring, the tension of which is varied with the barrelelevation, and which must, for the first round, be armedby a crank. After the round has been thrown into thechamber, the loading cannoneer swings the tray out ofthe path of the recoiling piece. This movement of the trayserves to fire the piece when set at "automatic" thoughit can also be fired by a right or a left hand firing lever.

The weight of the complete round is r4~ kilograms(about thirty-two pounds) while the shell itself is aboutnine kilograms or a shade under twenty pounds. Clock-work fuzes are used, and two fuze-cutters are located onthe left side of the piece. The shell is said to break up intosome 300 effective fragments on burstin~ and the de-tonating effect alone is claimed to be sufficient to put aplane out of action if within a radius of thirty meters ofthe point of burst.

"PREPARE FOR ACTION"

The command "Stellung" or, "Prepare for action" isone that the recruit hears early in his career, for veryshortly after his call to the colors, two hours of the after-noon periods are devoted to drill on the piece. At firstcarefully taught each and every motion for going intoposition and back to march order again, soon the element

of competition is stressed and every crew strives to be thefirst to report their Flak "readv."

After the mount is unhooked from its towing vehicle,and while some of the cannoneers unload ammunition andequipment before the tow truck leaves for the truck park,others lower the two sides cross-arms to the horizontal andlock them stoutly in place. The whole piece is thenlowered to the ground directly from the bogies by crank-ing suitable gear. Leveling is accomplished both by baseplates screwed to the ends to the cross-arms and at theundercarriage itself.

A panoramic sight is placed in position on top of thecounter-recoil cylinder and used to orient the piece. Mean-while fire control cables and telephone lines are run outfrom each gun to a junction box. The gun commander'sbreast telephone transmitter and head set are gotten Outfor him, connected up, and his "gun commander's firingtable"-used in certain phases of emergency fire control-is taken from its place on one of the cross-arms and handedto him. The open, and the telescopic sight for emergencyfire control use, are also put into their receptacles on thegun. The whole operation is performed with incrediblespeed, accuracy and quiet and if there is the least goodreason to move a gun or the battery, there is no hesitancyin carrying out the move. Time permitting, camouflagemeasures are initiated, the barrel pointed into the sun tothrow the least shadow, or perhaps a tree or branches aretied to it, pointed vertically. Camouflage is stronglystressed throughout the AA artillery.

THE "KOMMANDOGERAT"

There are two battery command posts. The principalone is lo~ated at the site of the Kommandogerat, or di-rector, which is always placed roo meters or more to theflank of the firing position. The director is a very sturd~'apparatus, comparatively simple in construction, with aminimum of mechanical and practically no electrical partS.Ballistic;values are read from drums. It is a linear calcu-lating apparatus, and the predicted point (treffpunkt) isdetermined in both the horizontal and vertical planes. Cor-rections may be set in for parallax, barrel erosion, loadingtime, wind and drift, and spot corrections for elevation,azimuth and fuze. The modern directors predict for div-ing or climbing flights.

The stereoscopic instrument, called the EM 4 m R (H)reads ranges from 670 meters upward and with the adjust-ing apparatus weighs 420 pounds. It operates as an integralpart of the director, with three men as crew. The director.owing to its mechanical simplicitY, requires an operatingcrew of ten men. In spite of this seemingly cumbersomegroup, an airplane flying at some 1,200 to 1,500 meterswas apparently tracked with ease. Short ranges ratherthan low altitudes determine the minimum effective firezone, targets under 800 meters range having too high anangular velocity to permit firing. It is claimed that a welldirected fire can be brought to bear on targets even underroo meters altitude if the range is not too short and safetyof friendly troops not jeopardized.

]Q39 GERMAN AA ARTILLERY TODAY 505

A PAGE FROM A GERMAN AA TEXTBOOKThe illllStration shows the standard sound locator. K7 is the sound lag cor-

rertor operator,. KB the azimuth listener: and K9 the elel'ation listeller.

instant of firing, and the lights can be made to burnbriahtlv or dimlv as needed bv varving the resistance to a~. / . / "-direct current furnished by storage battery cells. Disad-vantaaes are the need for a large number of conductors in::J ~the cable, and the 6-4 mil minimum azimuth setting. Thecables are understood to have 108 conductors. The break-ing of a few of the conductors would not, of course, inter-fere materi3]]v with the data transmission.

At Comm;nd Post No.2-in the center of the firingposition-we find the battery executive. Here also is afire control instrument called the Kommandohilfsgerat,which mav be translated as "auxiliarv director." Littleinformatio"n is available concerning this apparatus. How-ever, Schi]ffarth and Sachs state under the heading: "Firewith auxilial")' director" that, at this command, the range

If initial data reaches the guns intwenty seconds or less after the instantthe t~rget is first assigned. it is con-sidered that excellent time has beenmade.

DATA TRA~S}"IISSIO~

Of special interest is the data trans-mittinu s\'Stem. The three receivers

::J •

at the gun each have three concentriccircles of light windows. ten windowsor apertures in each circle. A pointer- better called a "cover" - nlovesover each of the light circles, and whenit is directly over a burning light, thelight appears red. As the data Rowsfrom the director, the lights illumi-nate one after another--much as thelilThts in an elevator Roor indicator. Ast>the azimuth operator, for instance,traverses his piece, the three "covers"move over the light circles, and wheneach of the burning lights-one ineach circle-is covered or shows red,the piece is set on the corrector data.One revolution of the inner cover orpointer, moves the middle coverthrough ten revolutions; and at thesame time the outer cover or indicatormakes 100 turns. As one completerevolution of the inner pointer is theeguivalent of a traverse of the gunthrough 6-400 mils, a movement ofthat cover from one light window tothe next, 1/10 of a turn, indicates amovement in azimuth of 640 mils. Amovement of the middle cover or in-dicator arm from one liaht window to

::Jthe next is the equivalent of sixty-tourmils, and when the outer cover movesfrom one light to the next, the pieceis traversed through 6-4 mils. This ap-pears to be the least or fine azimuthsetting, unless two lights, burningtogether indicate that the cover should be set midway be-tween for a fine setting of 3.2 mils ..

Oddly, elevations are measured in degrees and six-teenths of a degree instead of mils. Since the piece moves,from lowest depression (-30) to a maximum elevation of~5°, through less than a quarter-circle, the smallest settingll1 elevation can be about a fourth of the fine azimuthsetting. Actually a complete revolution of the inner coverarm, indicates a movement of 1000, and a movementof the outer cover arm from one light window to the nextindicates an elevation change of o. I 0 or about I.7 mils.Fuze settings go through 3500 with the smallest setting,°'50, only 700 windows being used on the fuze receiver.

The system has the advantage of simp]icic:' of construc-tion, ease of reading, steadiness of the settings during the

506 THE COAST ARTILLERY JOURNAL Noz'ellIber- December

officer, and his chief noncommissioned officer, with Nos.I and 2 of the height finder crew and B-4 of the directorcrew, proceed to this apparatus and locate the target in it.The E- I (stereoscopic reader) and B-4 report as in normaldirector operation.

In addition to indirect firing with the director andauxiliary director, direct firings are carried on with thetwo "Am's," and b:' free firing.

The first method is described in Captain Nauman'shandbook but is not mentioned by Schilffarth and Sachs.The "Am" appears to be an instrument for measuringthe horizontal and vertical angular displacements of atarget during a time of one third of the estimated time offlight. Based on the range given by the stereoscopicreader, a stop-watch operator signals his "Am" operatorwhen to start and stop his measurements. Two crewsoperate alternately and the vertical and azimuth leads aswell as the ranges are sent to the guns.

Using his "gun commander's firing table" the gun chiefcalls out the superelevation and fuze-cutting values to hiscrew. The battery fires on a signal, and though obviouslythe rate of fire is slowed down considerably, it is definitelynot stopped all together.

Free firing comes into use only when the apparatus forthe other methods is inoperative or not available. The firedirector has only ranges to aid him. Without ranges nofiring is attempted. The method is referred to as simple butinaccurate. The fire director must estimate the targetspeed and a true picture of its flight director. Based onthe range and his own estimates, made through knowledgeand experience gained in firings, he gives the' fire com-mands. He calls out the range, and the estimated hori-zontal and vertical displacements of the target. Using therange and target elevation, the gun commanders determinethe superelevation and fuze settings. For the "commandand loading time" about eight seconds is allowed as a rulethough some fire directors are able to cut this to seven oreven six seconds when working with a highly trainedbattery.

THE RANGE FINDER SERVICE

The German training regulations state that: "In firingagainst airplane targets, correct range determination is thebasic requirement in calculating useful firing data. Successin such firing, especially in the case of the heavy Flak,rests to the very highest degree upon the proper perform-ance of the range readers." Throughout the Flak artillery,the training of this personnel is strongly stressed, and theregulations go on to say that such training can never betoo rhoroughly or too painstakingly carried out.

In addition to stereoscopic eyesight, the requirements ofa good range reader are stated to be: high degree of quickperception, strength of resolution, ability to concentrate,high sense of responsibility, and strot?-gresistance to physi-cal and mental strains.

The course of instruction, both theoretical and practical,is very complete. Two students normally work together,one acting as recorder while the other reads. After initial

instruction on fixed targets, where a series of six readingsis twice made without removing the eyes from the instru-mem, readings are made on signal of the instructor,against time. Ever:' reading is recorded in a book whichthe student always keeps with him. The recording is madeat the time, if known, or entered as soon as determined bythe data section. The essence of the training is what th~student is able to learn from a study of his record bookfor therein he has recorded all conditions of the moment:the adjustments on his instrument, the nature of his er-rors and their relative magnitude. A good reader will givethe ranges every several seconds, generally accurate to thethird significant figure.

The proper and timely adjustment of his instrument isof great importance, but the most important element ofhis training is an accurate control of all practices. Of thetwo general methods used, the best is of course, work witha well trained record section. Cameras similar to those usedin our service are operated at the ends of a baseline, Whenthis method is not practicable, a thoroughly experiencedand trustworthy s,tereoscopic operator makes readingssimultaneously with those of the students, One methodor the other, however, is always used.

In working with the 4-meter base instrument (Em 4mR (H) stereoscopic contact with the target is maintainedcontinuously, except that on the signal the range knob ismomentarily held still so that the recorder can properlynote the reading (range or height) at the given instant,

As every light Flak-both z.o-cm. and 3'7-cm,-havea range reader, and each gun commander is supposed tobe a qualified operator, the stereoscopic range and heig;htfinder work is given much attention throughout the Flakartillery.

THE HEAVY SEARCHLIGHT (ISo-CM,)

To those familiar with our own searchlights there areseveral interesting points about the German light unitsand their operation. The heavy searchlight battery mansnine lights complete with sound 10cators,3 divided intothree platoons of three lights each. Though for peacetimetraining each heavy gun battalion has a searchlight bat-terv with it, the unit for all-around illumination is these;rchlight battalion of three batteries, or twenty-sevenlights in all.

As the lamp itself, as well as the power plant and thesound locator are each mounted on wheels and towed bvtrucks, the unit appears at first a little cumbersome. In theleading truck there is found, besides the driver, the li~htcommander and cannoneers Nos .. l to 4- In the vehicletowing the power plant there is the driver and cannoneersNos. 5 and 6; in the last truck, towing the sound locator,we find a driver and cannoneers Nos. 7 to 10, making atotal crew of fourteen men.

In the operating positions, the lamp and the soundlocator have their bogie trucks removed and rest on theground on four jacks with base plates. The power plant,

3Schilffarth and Sachs C),larch, 1938) show only six of the ninelight units to have sound locators: Schluchtmann's pamphlet ansearchlights (August, 1938) shows aU nine to have them,

1939 GERMAN AA ARTILLERY TODAY

2.0-c11I. Flak.

usually 200 metcrs awa\' from the light unit. consists of:lll el~ctric genetator of twenty-four- kilowatts capacit~"driyen b~' a gasoline motor.

The sound locator has the usual four horns, formed withthe cxponential curve, but each of the horns ma~' belikened to a funnel, bent into a U shape, with the smallend of all four coming together in the middle of thegroup. Seen from the front, the mouths of the horns, orfunnels, form a torus. The assembly of four horns is car-ried on a yoke which resembles the'one on our own hmpunits. Sea'ts for the listeners, one on each side, are attached:0 the base of the yoke, ;md above each seat is a ring towhich curtains, remindina one of those used in a shower.::;>bath, are hung to act as blindfolds for the listeners duringdadight drills. At each listener position there is a smalllight switch, which when closed, lights two small signallamps, one in front of the sound lag corrector operator, theother in front of the opposite listener. When either listeneris cemered on target, he signals the fact by closing theswitch.

The sound lag corrector is built into the base of theyoke and is operated b:' ClI1noneer No.7. The light com-mander or the operator himself estimates the target speed:1lldsets it into the mechanism. A correction for variationsin the velocit:. of sound is also set in. The average velocityis determined from information furnished bv a meteoro-logical section. The data transmission svsten; is the sameas that used between the director and' the guns, an azi-muth and elevation receiver being mounted on the bmpitself.

There is no distant electric control. Cannoneer No. 2setting the lamp in elevation from his position at the lamp,and No. 3 moving it in azimuth bv means of the hand

control bar. Cannoneer No. 3 can also make small ele-vation changes. At the command "in action", No.2 opensthe lamp shmter. Abom three seconds is allowed for theeye to become accllStomed to the light before any search-ing is started b:' No.3. The light commander assists himfrom a post nft." to one hundred meters to the side andtwenty to thin." meters in rear. No. 4 also assists in thesearch.

A unique feature of the light is the provision for scarch-ing with a sprcad beam, using the focused or sharp be:lll1for carrying. The spread beam is a 40 cone which at10,000 mcters slant rangc has a width of abom 700 meters;The sharp focused beam is a J 0 9' cone and has a cross-section of 250 metcrs at this range.

There arc two methods of searching. When workingwith sound locator data, after three seconds the beam iselevated a beam-width and then moved through 3600 ina counter-clockwise direction, tangent to the initial coneposition. Abom nve seconds arc allowed for the move-ment. When working without sound lo,ators, the beam ismoved in a vertical arc of from 200 to 300 mils and at thetop and bottom of each movement it is moved in azimmhabout a beam width. For a coming target, the movementis deeper and narrower than for a passing target.

LISTE:"FR TRAINING

The training of listcners is progressive, and continuityof practice is heavily stressed, some t:'pe of listener workbeing carried on ever~' da:' of the week. For basic listenertraining, :lS well :lS for use during inclement we:lther, aninteresting design of bin:lut:ll trainer is used. There aretwO record pla:'ers, one for the principal sound, while thesecond pb:'er superimposes :l disturbing sound, the type

50S THE COAST ARTILLERY )OCRNAL--,

So/'ember- December

8.8.c1I1. Flak. Projectile ollloadillg tra)'.

an~ intemity of which :lre varied to suit progress, ThetLllner accommodates six listeners at a time.

~ good deal of work is carried on b.', da.", the practicebeing controlled b." suitable apparatus, to show theamount of variation between the target and the simulatedlight beam,

FIRING TRAINING Al"n TARGET PRACTICE

Training on the light Flak begins much as does our ownwork in riRe marksmanship, The usual sighting drills areheld and checked as in our barrack yards. Then followstraining in the various oper:ltions req~,ired for a sight set-ting, The sight operator has to set :l poimer on the base ofthe sight, parallel to the t:lrget's Right; so pr:lctice isc:lrried on in this operation, :lnd each seninCT carefully~ .checked. Training in estimating target speeds must begiven, and some training in range estimation is also c:lrriedon, for use in the event rhe range reader onnot furnishthe necessary ranges. Firing practice starts with singleshots at hxed targets, followed by short bursts, and thencomes hring at moving targets. Scores are kept for eachgunner.

\Vhen tracer hring is done the data is still kept set inthe sight mechanism so th:lt the latter can be instantlyused on command.

Combat hring is the gO:l1and is made as realistic as ispossible. Situations requiring an instant decision of thegun commander as to which targets to take under fire are

8.8-C11/. Flak 11/01tlJtd 011 flatcar.

arranged; also yroblems requiring :l ch:lnge of t:lrget, ore\'en the openIng of hre from the traveling position, :ltecarried ou t.

Virtually all service practices of the heavv batteriesh.l\'e been conducted at \Viistrow on the Nor~h Sea, thelocation of the Flak Artiller." School. This is due primarilvto !ack of adequ:1tc hring ranges in the densely populatedReICh; but there are many compensations for the dif-hculties involved in sending the b:ltteries to \Viistrow.

As the short hring se:lson in pC:lcetime is not enolJUhf ' I nor elt ler tr:lining or maintaininCT efficiency at the home

....... tJ -' 'stations resort is h:ld to a simulated firing pr:lctice calledoptischen Erprobungen or optical testings. One or moretarget planes may be used, and having no sleeves to tow,the,' may simulate actual war conditions very closely. Thepaths oE" the target planes are very accurately dete~minedby camera theodolites at the ends of a b:lseline.

Eleven recorders are used at the director :lnd three ateach gun, Norndly the b:lttery hres every three secondson signal and the data readin2:s are taken on the sianal

u nfor the simulated hrings. Firing data is calculated to in-clude drift, wind eltects, barrel erosion, etc" but in theanalysis these elements are cancelled where necessary bycnte'ring them with opposite signs. The instant of s'inll;-lated burst is determined from hrinCTtables. Bv means of~ ,a carefully worked out procedure for :In:llysis, personnelerrors (including of course the work of the height hnderoperator) ma." be determincd. With a thorough I." trainedstereoscopic operator, the base end instruments are some-times dispensed with, his readings being taken as correct.

A system of mirror hrings, also referred to by Schilf-Earth and Sachs, uses the optical law that angle of inci-dence equals the angle of reRection. Bursts are actuallydist:lnt from the target but appear to observers, by me:IOSof :In :lrr:lngemem of mirrors, :lS if actually hred :It it.

Service pr:lctices of the heav." Flak are m:lde as re:llisticas possible. They begin, in part at least, with the piece inthe tr:lveling position. Situations requiring quick decisionsof the battery commander or executive are developed, aswell as ones requiring changing of targets. Firings arecarefully controlled, cameras at base ends bein~ used andall data carefullv noted, at each s:lIvo, bv a staff of record-ers. It is cbim~d that an analysis of a practice will show

1939 GERMAN AA ARTILLERY TODAY 509

up personnel errors, whether of the director crew. therange re3der. or even one of the d3t3 seners at 3 gun.

DEPLonIE:-;T

"To be 3t the right pbce at the right time, 3ble to openetlecci\'e hre in the shortest possible time" is the basicpnnciple for deploymem 3nd the fulhlmem of ~hese re-quiremems t3kes precedence over all other t3c[(c31 3ndtechnic3l consider3tions for the m3rch or preparation for3C£lon.

The regubtions go on to S3:, that the gre3t mobility of(he .Iir 3(t3cke(, plus his 3bilit:. to 3n3ck from 3n:' direc-(ion. might 3t hrst thought lead to 3 wide deplo:'mem of(he Fbks with the ide3 of engaging the enemy from thegre3test number of pbces possible. Actuall:' such pro-cedure leads, they S3Y, to 3 "splining of power" and is tobe rejected.

Frederick the Great, long before the da:' of the Fbks.said: "He who tries to protect ever:,thing. protectsnothil1

510 THE COAST ARTILLERY JOURNAL i'\ol't'1JJber- Deci:1J/br:rJ.rmed forces-recei\'e training in the use of the rifle andmachine gun for defense against low fl~\'ingenemy air-planes. Every text or pamphlet on Flak artillery makes adefinite reference to this subject, some devoting quite alittle space to it.

They say that they have come to "a realization that welldirected rifle and machine-gun fires-provided of coursein sufficient numbers-afford a not to be underestimatedthreat" to the attacker. For worthwhile effect, it is saidthat from fifteen to twenty riflemen should fire together,and many tests have shown that rifle fire by such a groupwill give as many or more hits than will be gotten from amachine gun.

The Germans claim that the failure during the war of1914-18 of the rifleman and machine gunner to performwith credit against enemy airplanes was due to a lack ofknowledge as to how to train for this type of defense.

Rifle fire is effective against low flying planes up to 600meters, against dive bombers, flying directly towards thedefenders, up to 1,000 meters. The crews of even the lightFlaks, designed primarily for use against low flying planes,must always be able to take up effective fire with theirrifles in event of stoppage of their primary weapons. TheriRemust always be near at hand for instant use.

The cannoneer fires from the standing, kneeling, proneor whatever position is most expedient. He first aims onthe nose of the target, and at the same time takes uptrigger slack. Then swinging the muzzle of his piece inthe direction of the target's Right (except in the case ofthe dive bomber) until he has the required lead, he fireshis piece.

Training starts wirh the usual sighting exercises, butmost important is the estimation of the lead, measured inunits of target length. He memorizes a few basic rules.With an approaching, leaving or passing target of a speedof sixty to eight:, meters per second, the lead in planelengths is equal to the range measured in hundreds ofyards. For targets of over eighty meters per second thelead equals twice the range value measured in hundreds ofmeters; that is, for a target moving at a speed of ninet:'meters a second, at a range of 500 yards, the lead wouldbe ten target lengths.

A board with airplane silhouettes painted on it, in vari-ous attitudes of Right, is used in the basic lead training.With the riRe on a sand bag rest the student points hispiece a given number of lengths ahead of the figure.Having positioned his rifle, his estimate is checked by the

use of the sighting disk. After three trials the usual to-angle is drawn.

Small bore firing is conducted on indoor ranges durin~the winter season, and practice at moving silhouettes [~conducted. The figure of the airplane, moving in front oithe cloth, has a target fastened to it at the prescribeddistance ahead of it in plane lengths, but moving unseenby the firer, behind the cloth. The result of the shotshows on the target. In the later seasons, firing at actualsleeve targets is conducted.

RELATION OF MILITARY AND CIVILIAN AIR DEFENSEORGANIZATIONS

The Reichs-Luft-Schutzbund, or National Air DefenseSociety, is an organization of more than four millioncitizens. Its primary mission is the protection of the livesand property of the civilian population in the event ofenemy air attacks on their cities, towns and factory areas.It is also charged with the organization, training andoperation of a nation-wide airplane warning service.

Civilians not available for regular military duty, thefarmer and his wife, the school teacher and some of herpupils, and the operators of the State telephone service.all fill their places in watching for the enemy airplanes andreporting them to the evaluating stations. They are expect-ed to perform invaluable service for the Flak artillery.

While the Society is composed practically entirely ofcivilians-including the local police organizations-thereal head is in the officeof the commander of the Flak ar-tillery in Berlin.

From time to time all the largest cities and many of thesmaller ones hold air defense practices, including black-outs. The exercises are always arranged to include the £1:,-ing troops and Flak units of the local air force district.

It will not be amiss to conclude with the thoughts ofMajor von Pickert, of the National Air Ministry, whosays that although modern antiaircraft artillery will offera high order of resistance to the air attacker, it must everbe borne in mind that in the air as well as on the ground.a resolute and firmly carried out attack cannot be com-pletely stopped. To render such attacks so costly that theenemy is either broken or so weakened that additional ef-fort is difficult, is the task of well equipped, capabl;'trained and operated Flak artillery.

The morale of the enemy, as well as his materiel, will besubjected to great wear and tear. How long the enemy cancarryon, in spite of these factors, depends in the long runon how well the Flak artillery performs its task.

THE

**By Lieutenant Colonel Harry C. Ingles

Signal CorpsThe new division organization, which the Secretary of

War has recently approved and under which the RegularArmy will be reorganized in the near future, is the resultof several years of study and experimentation by the WarDepartment. Many officers are now familiar with the ap-proved organization but only a few know the many stepsthrough which it was evolved.

There has been for years a body of well-informedopinion in the Army that the Army of the United Statesshould be organized into small, highly mobile, hard-hit-ting units. In the hearings before the Congressional com-mittees ever since 1930 we find recommendations by highWar Department officials that our army be thus reorgan-ized. However, our basic large unit-the infantry division-remained, until recently. the exact opposite type-large, slow, not well adapted for maneuver. and not par-ticularly hard-hitting. No effective remedial action waspossible prior to 1935, as the Regular Army was toosmall and no funds were available to equip small divisionswith the modern armament and transportation necessaryto make them as effective as the large ones which existed.

In 1935 the situation began to change. The authorizedstrength of the Regular Army had been increased to165,000. A PW A grant had made it possible to increasematerially the number of modern motor vehicles in theRegular Army and the National Guard. A program hadbeen approved to procure semiautomatic riRes, 81-mm.mortars, 37-mm. antitank guns, and highly portable andmore efficient communications equipment, ;md to mod-ernize the 75-mm. Funds to carry out this program werebeing made available.

By that time, also, European powers were universallyemploying the triangular type of division-built aroundthree regiments of infantry-which were much smallerand considerablv more maneuverable than our division.Another thing ~hich pointed to the reorganization of our

own division was the Japanese experience in lvfanchukuo.By 1930 the United States and Japan were the only majorpowers still adhering to the large square division builtaround four regiments of infantry-two brigades of tworegiments each. The Japanese division had a strength ofabout 24,000 and ours, about 22,000. The Japanese foundthis division much too large and unwieldy to handle inthe open-warfare situations encountered in Manchukuoand promptly reduced its strength to approximately18,000, but retained the square organization. But even atthis reduced strength they still found the square organi-zation hard to handle, and have now gone to a triangularorganization of about 12,000 men built around three regi-ments of infantry.

In 1935 a committee was appointed in the War Depart-ment General Staff to study the modernization of theorganization of the Army and submit recommendations.The reorganization of the infantry division was to be thefirst step. At the same time the War Department calledupon corps area and department commanders, chiefs ofarms and services, the service schools, and many individ-uals for recommendations for a division organization.

The committee was directed to analyze and study theserecommendations, study the organization of all foreigndivisions, study and evaluate the modern improvements inweapons and transportation and formulate a reorganiza-tion of our division. The directive did not prescribe thetype of organization that should be evolved, but it diddirect that whatever organization was recommended itsmobility off the battlefield must not be restricted to thegait of the foot soldier or the horseman.

The committee made an exhaustive study of foreigndivisions and of all the recommendations submitted fromthe various sources throughout our army. It also conductedextensive hearings during which all chiefs of arms andservices and many other officers appeared and gave their

512

CommandEchelon

Reron-nais-sauce

Echelon

THE COAST ARTILLERY JOURNAL

Initial Organization Proposed for Test

CombatEchelon

N Ol'ember- December

ServiceEchelon

.-tppro.,imate Strel1gthPeace: 535-0flicers

I-W.O.9.809-Eo1. Meo

War: 689-0flicers1-~/.O.

12.862-Eo1.1\1eo

Figure 1

views on the division organization. All the Europeanpowers then had, as they now do, triangular divisions,built around three regiments of infantry and varying instrength from 12,000 to 17,000 men. As was to be ex-pected, there was a wide difference in the recommenda-tions received from throughout our own army. However,the great preponderance of the reports recommended atriangular organization, made highly mobile by motori-zation, and much smaller than our old division,

On the basis of the above data the committee submitteda proposed division organization with recommendationsthat it be tested theoretically in the schools bv means ofmap exercises and problems', submitted to chiefs of armsand servicesand corps area commanders for study and com-ment, and tested practically in die field by assemblingsuch a division in the Eighth Corps Area. The committeereport was approved and these recommendations werecarried out. The tentative organization which was thentested as outlined above is shown in Figure I.

For the practical field-service test a complete division,organized in this manner, with an antiaircraft battalionand antitank battalion attached, was assembled in theEighth Corps Area and engaged in maneuvers for aperiod of two months. The reports on the field-service test,on the theoretical tests in the schools, and on the studiesmade under the direction of the corps area commanders,with one exception, all recommended the adoption of asmall division following the general organization of thedivision proposed. However, as a result of the studies andthe tests-particularly the field-service test-the follow-

ing major defects in the proposed organization came tolight:

(I) The subdivision of the organization into com-mand, reconnaissance, combat, and service echelons servedno useful purpose but tended only to complicate it.

(2) The services of a mechanized cavalry unit werehighly desirable in many situations, but a whole squadronwas not required for a single division. Since a squadroncould perform distant reconnaissance over a front oftwenty-five to thirty-five miles, one per corps appearedto be better.

(3) The 81-mm. mortar, which, in the proposedorganization, was handled by the artillery, was definitelyan infantry weapon and should be assigned to infantry bat-talions.

(4) Heavy machine guns, which, in the proposed or-ganization, were placed in a machine-gun battalion,should be organically included in the rifle battalions.

(5) There was not enough artillery.(6) The proposed organization authorized 1,866 motor

vehicles. This was about twice the number required.(7) The organization of the services in a single echelon

under a general officer was unnecessary; it merely intro-duced another headquarters between the division com-mander and the commanders of his essential services.

(8) The ordnance maintenance company could main-tain the equipment of more than one division and shouldaccordingly be shifted to the corps.

Reports from the schools and the corps area commandersgenerally questioned the unusually large artillery regiment

1939 THE NEW DIVISION

The New Division

513

" Combined into oneDiv. Hq &. M.P. Co. in peate: organization.

b Service Co. is a platoon of theEqrs. Co. in peace organization and partialh inacrhe.

p~Pfe;oxi.tllt! ..~~~cers •3-W.O.

S,517-Ehhsred MenWar: 6OO-Offit'c:rs

3-W.Q.11.300-Enli~led Men

Figure 2

Infanto"R~

FieldAnille

514 THE COAST ARTILLERY JOURNAL N O1'ember- December

division headquarters differs from that of our old divisionin several respects. It is smaller. The G-1 section of thegeneral staff has been eliminated. And infantry and ar-tillery sections have been included in the division staffeach headed by a general officer.

Investigation of the duties performed by G-I in thedivisions during the World War brought out that theseduties could be performed by the division adjutant, andthat consequently there was no need for a G-1 section.

During the entire period the new division was underconsideration, there was a great diversity of opinion-and there still is-as to the necessity for having any gen-eral officers in the division subordinate to the divisioncommander. The French and Italian divisions include in-fantry and artillery generals, but we have not, in the past,had positions exactly analogous in our own army.

It is not contemplated that the infantry and artillerysections will act as separate headquarters and issue fieldorders to the divisional infantry and artillery. They mayparticipate in preparing division orders, or even write theportions that direct the action of their respective arms ifthe division commander desires. But the order of the di-vision commander will make direct dispositions of theregiments to be executed by the regimental commanders.

The major duties of the chiefs of the infantry and artil-lery sections will be to plan, coordinate and supervise thetraining of their arms; to advise the division commanderon the use of their arms; and to assist the division com-mander as he may otherwise direct. The infantry generalmay be ordered to command the assault echelon or im-portant mixed detachments, such as advance, rear, orflank guards, or enveloping forces. The artillery sectionwill be charged with coordinating artillery fire, particu-larly with handling reinforcing artillery and coordinatingits fires with those of the organic artillery.

When they are exercising such command functions asthe division commander directs, the infantry and artillerygenerals will normally be located at division headquartersand will use the division signal system to all the regimentsfor their communications needs. If the division com-mander orders one of them on a mission that requires himto establish a command post separate from that of thedivision, his communications requirements will be pro-vided by the division signal company.

The organization of the division signal company re-mains practically the same as in the old division. In thenew organization it must provide, operate, and maintaincommunications channels to five immediately subordinateheadquarters, and between these headquarters, instead ofonly three.

The infantry regiments are organized in accordancewith T able of Organization 7-I I. This organization wasapproved about a year ago and the regiment and its tacticswere discussed by the Chief of Infantry in The INFANTRYJOURNALfor January-February, 1939,

The organization of the division artillery has been thesubject of wide experimentation. In our old division theartillery organization was extravagant of personnel, re-

quiring within the division alone at war strength seventy.eight officers and men per gun to maintain an anillen>support of 5,9 guns per 1,000 infantry. With motQriz~artillery in our old division this is reduced to fifry-nine of-ficers and men per gun. In the new division, artillery Over-head is materially reduced and at war strength is approxi-mately forry-two men per gun to maintain an artillerysupport of seven-plus guns per 1,000 infantry. The light-artillery regiment is organized into three battalions, eachwith three firing batteries and its own combat train. Thisprovides a battalion of twelve guns for the direct supponof each infantry regiment, as in the old division.

The medium artillery, 155-mm. howitzer regiment, isprovided for general support of the division and to rein-force the fires of the direct support battalions as required.It is a two-battalion regiment, each battalion containingtwo firing batteries and its own combat train. This organi-zation would be more economical if each battalion hadthree firing batteries, for this would provide more fi.~power with practically the same overhead. However, thiswould give a small division more medium artillery thanis warranted. It is better to reinforce the division withmedium artillery when the tactical situation demands it.At one time, it was believed desirable to replace the di-visional Iss-mm. howitzers by lOs-mm. howitzers. Buttoday the trend is toward heavier calibers, and it is nowprobable that if the lOs-mm. howitzer is introduced intothe division, it will be a replacement for the 75-mm.gun, and not for the I55-mm. howitzer.

The organization of the engineer battalion is basedupon the transfer of certain engineer duties from the di-vision to higher echelons. All heavy road work, map re-production, and floating-bridge construction, includingfootbridges, are now transferred to the corps or higherechelons. The engineer battalion is organized for theprimary duties of engineer reconnaissance, improvementand maintenance of existing roads and trails, strengthen-ing of bridges, demolitions, mine and obstacle defenseagainst mechanized attacks, field fortifications, and thetransportation and issue of tools.

The universal use of motor ambulances, with theirgreater range and speed of movement, has made it de-sirable to shift the hospital station and hospital companiesentirely out of the division, retaining only enough medicalpersonnel for a dispensary service when the division isback of the lines, and to operate facilities for shock treat-ment during combat. The principal duties of the medicalbattalion are collection and evacuation of the wounded tohospital stations established and administered by the corps.Provision is made for litter-bearer units to evacuatewounded from aid stations to collecting stations and formotor ambulances to remove them to hospital statio~sestablished by the corps. Attached medical personnel tothe infantry regiment has been materially increased overthat in the old division and has been kept about the sameas before in the other divisional units. A medical detach-ment of forry-eight men was attached to the large infantryregiment in the AEF. Data collected during the study

1939 THE NEW DIVISION 515of the new division organization indicated that this wasfar too few in combat and the detachment has thereforebeen increased to ninety-six attached medical enlisted menfora regiment considerably smaller than those of the AEF.

A number of considerations influence the organizationof the quartermaster battalion. In the first place, only thetransportation needed for continuous use should beorganically assigned to the division. No ammunitionbeyond that in the unit combat trains, prime movers,and weapons carriers, and that on the soldier, need becarried in the division. At the beginning of the rationcycle, there should be one and one-third rations on tnekitchen trucks. One reserve ration should be carried intrailers in the quartermaster battalion, and no otherrations need normally be carried. No gas and oil beyondthat in vehicle tanks and in containers on vehicles needbe normally carried in the division. A gas-and-oil servicemust be provided at the railhead for refilling. When it isdesired to move the entire division by motors, or whenthe division is assigned a mission that requires it to carryextra ammunition or Class I supplies, additional trans-portation should be provided from a higher unit.

It is safe to assume that a railhead, or truckhead, forthe division can be established within thirty miles ofthe front. The quartermaster battalion should haveenough transportation to deliver rations, fuel, and waterfrom this railhead to the regimental areas during thehours of darkness. The unit combat trains will haul am-munition direct from the refilling point to the troops. Indetermining the quartermaster transportation required, fullcognizance must always be taken of the fact that motors,in many situations, will be able to make a number oftrips.

Within the division the motor-maintenance functionsof the Quartermaster Corps consist principally in limitedthird-echelon maintenance, an inspection-and-spare-partsservice, and the evacuation of disabled vehicles to repairshopsestablished by higher echelons. No disabled vehiclethat will take more than three hours or so to repair shouldbe handled in the division. The quartermaster battalionshould furnish the passenger transportation required bydivision headquarters, and should provide labor for therailhead and refilling point, and for burials.

The quartermaster battalion of the new division isorganized to meet these many demands, and certainheadquarters, motor maintenance, gasoline and oil sup-ply, labor, and truck units. To conserve overhead severalof these units are consolidated in the headquarters com-pany for administration, mess, and supply. The deliveryof rations every twenty-four hours will require aboutthirty tons of cargo transportation in the peace organiza-tion and 40 tons in the war organization. In order to handlethis, and also provide a small emergency pool, forty-eight I ;/z-ton cargo trucks are allowed for the peace-strength truck company and seventy-two for the war-strength. In addition, enough three-quarter-ton trailers areincluded to carry one reserve ration for the entire division.Trailers are preferable to trucks for this purpose because

the reserve ration does not have to be unloaded, and is thusa truly rolling reserve that can move with the division orstay behind to be brought up as needed or whenevertrucks are available for towing.

It was found by extensive and thorough field-servicetests that the present division ordnance company had amaintenance capacity far in excess of the requirements ofthis small division. It was therefore apparent that thiscompany should be transferred to a higher echelon, whereit could handle the ordnance maintenance for more thanone division. An ordnance section is included, however, inthe division headquarters company, mainly to operate theammunition refilling point (the labor is to come fromthe quartermaster service company), the ammunitioncontrol point, the division ordnance office, and an inspec-tion and limited spare-parts service, and to superviseordnance supply. Unit commanders are responsible fortheir ammunition supply from the refilling point, usingtheir combat trains for the purpose.

The division headquarters company and military policecompany are designed to carry out the same functions asthey have in the past. They are combined into a singleunit in the peace organization in order to reduce ad-ministrative overhead.

The transportation of the division is completely motor-ized. Through the whole period of considering and testingthis organization, the question of retaining animal trans-portation has been much less controversial than was ex-pected. The great preponderance of reports favored motori-zation of the division transportation.

The press has generally referred to the triangular di-vision as a "motorized division." It is not a motorized di-vision. The Army definition of a motorized unit is onethat has enough motors to move all personnel and equip-ment at the same time. In the triangular division the in-fantry walks, as in the past. What has been done is toreplace animal-drawn transportation and riding horsesand mules with motors. The entire division with all of itsammunition and equipment cannot be moved by motorsat one time without additional transportation furnishedfor the move.

At the same time, movement of the entire division bymotor has been greatly facilitated by eliminating animals.In a division containing animals, it was impossible toutilize the mobility of motors fully because, even with anample number available, the division could not movemore than twenty or twenty-five miles per day-themarching capacity of the animals. A few animals can beentrucked in vans and move with the speed of a motorcolumn, but it is impracticable to move all the animalsthat were formerly assigned to the square division in thismanner. Even though the entire division, carrying itsnormal load of ammunition, cannot be entrucked withoutadditional vehicles, it nevertheless has, with its organictransportation only, a considerable mobility. By shuttlingit can march at least forty miles per day and maintain thisrate day after day. And in a movement where there is nodanger of enemy interference, and all combat-train loads

~OLDDIVISION

NEWDIVISION

RIFLES .30 CAL. SEMI-AUTOMATIC

8160-MM MORTARS

~o108

144144

.30 CAL. HEAVY MACHINE GUNS

~ 12 (3"STOKES MORTARS18

Major Armament of New81-MM MORTARS

NEWDIVISION

OLD ~ "'-"'-"'-"'-"'-"'-"'-"'-'1DIVISION~

4773

12 (MODEL 1917) ~18

o

18O~

48~I 36(,,j

{

2416

and Old Division

518 THE COAST ARTILLERY JOURNAL Novembe,.- Decembercan be dumped and ammunition vehicles used for troops,the whole division can be entrucked. In one of the marchesduring the first field-service test of the organization, theentire division broke camp, ate breakfast, entrucked,moved 345 miles, and had the tail of its column in its newarea in sixteen hours' time.

There were, of course, a number of major reasons thatled to the decision to motorize the division transportationcompletely. To begin with, the original directive of theChief of Staff stipulated that, whatever organization wasadopted, its speed of movement must not be restricted tothat of the foot soldier or horseman. Again, the experienceof the Army since 1934, when a large degree of motoriza-tion became effective, has conclusively demonstrated thatthe modern truck has remarkable cross-country mobility.The extensive field tests conducted with the triangulardivision, and tests of smaller units of all arms all overthe Army, have similarly demonstrated that the modernall-wheel-drive truck has a cross-country mobility at leastequal to any other wheeled vehicle.

The mission of the War Department was to design anorganization for the future, as well as for the present.Animal transportation is at a standstill. It has today all thefaults and virtues-and it has many virtues-that it hada thousand years ago. No material improvement is pos-sible. Motor transportation, on the other hand, is gradu-ally improving each year. It is only necessary to look backand compare a World War truck--or even one of tenyears ago-with a modern motor vehicle. And five yearsfrom now, they will be still more improved structurallyand mechanically over the present models.

There are still further reasons of importance. The de-velopment and standardization of a satisfactory motorweapons-and-ammunition carrier made it possible to elimi-nate mule-drawn carts for infantry weapons. Motor trans-portation over a period of five years or longer, taking intoconsideration first cost, depreciation, maintenance andoperation, is considerably less expensive than animal-drawn transportation. And finally, the United States hasmore motor vehicles than all the other major powers puttogether and has by far the greatest motor industry. It isincumbent on the Army, and moreover thoroughly sensi-ble, to utilize our national resources.

In our army the so-called peace organization and peacestrength are important. They form the initial organizationand strength for combat. No great reserve of trained menis available; hence, the peace organization cannot be ex-panded to war strength until a considerable time after M-Day. When this expansion comes it will occur in themidst of war, and it should not cause a reorganization.Consequently the peace organizations of all major units inthe triangular division are the same as the war organiza-tions, though the subordinate elements may be smaller insize. For example, rifle companies have four platoons inboth peace and war organizations, and the rifle platoonsthree squads, though at peace strength the squad has onlyeight men. The expansion of the infantry regiment frompeace to war strength does not require the activation of

any new elements but is chiefly accomplished merely hyadding four men to each rifle squad and making smallincreases in the strength of some of the special-weaponssquads. Since ammunition-carrying personnel requiresbut little training, artillery combat trains and infantry am-munition sections, though a part of the peace organization.will not normally be active in time of peace, but will beactivated on M-Day.

The question as to whether this new organization neces-sitates any material change in our tactical doctrine is animportant one. After working with the new organizationfor a period of over five months, the Army War College.the Command & General Staff School, the InfantrvSchool, and the Field Artillery School, all reported thatthe triangular organization did not make any materialchange in our established tactical principles or doctrineand their application. Itwill, however, undoubtedly neces-sitate considerable revision of textbooks and instructionalmaterial.

The slowness with which the square division reacted toorders has long been a cause of worry in our army. Owingto the type of organization, smaller size and the elimi-nation of unnecessary headquarters, the triangular di-vision reacts to orders very much quicker. The distributionalone of orders in the old division required from five to sixhours. Very complete data kept during the two extensivemaneuvers of the new division indicate that it reacts toorders-all troops in motion or ready to move-in ap-proximately two hours.

The ability to sustain combat has been a major con-sideration throughout the study of this organization. Theability of any division to stay in the line in a defensivesituation and to continue its advance in offense is largel\'determined by the amount and effectiveness of supportingartillery and by the number of infantry battalions thatcan be initially held in reserve. The artillery support inthe new division is as strong as in the old, but there areonly nine infantry battalions as against twelve. But thenew battalions, it should be noted, are smaller than theold. It is probable, therefore, that a single triangulardivision does not have the same ability to sustain com-bat as did the old square division. However, it must beremembered that in modern war the power to sustai~combat, either offensive or defensive, on a given front ISnot determined by single divisions. It is determined b\'the organization of the corps or even armies on that front.The problem of organizing for sustained combat is notthat of the organization of a single division. It is a problemof how best to organize, say, 50,000-60,000 men, in orderto secure the maximum of sustained effort. A corps con-sisting of corps troops and three of the new divisions willaggregate about 50,000 men. A corps containing twO ofthe old divisions will aggregate about 60,000 men. Theartillery support is the same in both cases and the frontabout the same. However, the corps made up of the newsmaller divisions has twenty-seven battalions of infanr:;' ~against only twenty-four in the other corps. Agatn Itmust be remembered that these new type battalions arc

1939 THE NE\X' DIVISION 519

smaller dun the old battalions. Therefore, the corps of thenew divisions, though numerically smaller by approxi-

• mately 10,000 men, has-it is believed-a staying powerat least equal and probably greater than the one organizedwith the old division.

The major armament of the new division is showngraphically on page 526, and is compared with similararmament of the old division. It may be noted that manyweapons, notably the single-shot rifle and Browning auto-matic rifle, have been eliminated and a number of newweapons introduced. In most infantry regiments, themodified Browning automatic rifle, with bipod, butt-plate,and cyclic-rate device, is now used as a substitute for thelight machine gun until sufficient machine guns can besupplied. The modified Browning automatic rifle is prov-ing co be such a valuable weapon that it will probably beretained even after light machine guns are available forits replacement. At present it is not included in the arma-ment of the divisional infantry, and just where it will bellSed if retained has not been finally determined.

It has not been the purpose of this article to discuss the

tactics for the employment of this division, but simply itsorganization. However, it is pertinent co point out thatthe organization is designed to move and fight in combatteams, each consisting of a regiment of infantry and abattalion of light artillery. In so far as possible thereshould be an element of permanency in these teams, thesame battalion of artillery always being associated withand supporting the same regiment of infantry. Combatteams thus constituted are small and compact enough tocamp, move, and fight together. They furnish a combatunit small enough to be easily handled but of great power.

Probably none of the many officers who have workedon this organization or assisted in the numerous tests of itever had any ambition to produce a perfect organization.In bct, a military organization that is perfect under allthe varying conditions of warfare does not and never willexist. However, the writer believes that the new UnitedStates division is superior to our old division. It is modernand its organization will permit the maximum employ-ment of improved weapons and modern means of trans-portation.

LIGHT AA GUNS AT THE FRONTTbis official Britisb picture sbows

1II

IS B~lltVIN'

oast Artillery Corps

Figure] :lereoscoPic Tesler j\fJ.

Self-contained range finders have been in uselroughout armies and navies for many years. UntillOut twenty years ago, our own Navy and Coast.rtillery Corps used the coincidence-type range find-. exclusively and our experience with the stcreo-opic type was practically negligible. This may seemrange when we reflect that both types were con-:ived at about the same time, shordy after the close: the War between the States. Years ago, the phe-Jmena of stereoscopic, or binocular, vision, althoughJt thoroughly understood, were widely recognized; may be witnessed by the fact that no home was)mplete without its parlor stereoscope and a set oficture cards.At the time of my entry into the service, one of the

urrent topics for discus-on in the Coast Artil-ry Corps was the Battle: Jutland. Available re-xts indicated that the;e of stereoscopic rangenders was largely re-lonsible for the gunnerylCCesSes of the German

Iy Captain~DWARDIARBER

1939 SEEIN' IS BELIEVIN' 521

Navy. Also, it was reported that in order to obtain themerehandful of observers required, every man in the Ger-man Navy was tested for his stereoscopic ability. This re-port was widely interpreted to mean that only one man infivehudred was capable of becoming a good stereoscopicobserver.Although, in my opinion, the report is now con-sidered to be a clever bit of post-war propaganda, for anumber of years it had marked effect upon our attitudetoward the stereoscopic range finder. This attitude isdearly indicated in an instructor's notes at the CoastArtillery School in 1931:

STEREOSCOPIC HEIGHT FINDERS

Disadvantages.Hard to obtain and train reliable observers. A soldier is

apt to have his position go to his head. Observer should bean officer, but comparatively few officers have the propereyesight.

Thus was the mystery of the stereoscopic height finderpreserved and a halo placed upon the brow of that super-man, the stereo observer.

During the World War and until 1925' our antiaircraftservice used the two-station altimeter to determine alti-tudes. In 1925, the need for a self-contained height finderbecame clearly recognized and as a result, several wereobtained for test at Aberdeen Proving Ground in 1926.The development and test of height finders continued forseveral years. Complete reports of the tests at AberdeenProving Ground are available and these contain muchdata of interest to the Corps. A few extracts of these re-ports are quoted in order to partially justify our reluctance,and even refusal in most cases, to accept the stereoscopicheight finder as a member of our family of antiaircraft firecontrol instruments in good standing.

In 1926.The disadvantages of the stereoscopicheight finder are:

Becauseof the stereoscopicprinciple, a highly skilled opera-tor is required.

The judgment of the operator is involved, and therefore issubject to error.

It is an optical instrument requiring expert maintenance.It cannot be used in trial shot firing, the bursts being

too poorly defined to permit of accurate readings.It is heavy and must be transported with care.It is not procurable cheaply and quickly.

In 1927'The accuracyof the height finder tested is not satisfactory.

In 1928.The conClusionsdrawn from a study of the results of the

accuracy tests of x x x x range and height finders are asfollows:

a. That the stereoscopictype height finder is superior inaccuracy to the coincidence type.

b. That to attain an appreciable increase in the accuracyof fire a more accurate altitude measuring instrumentmust be employed.

c. That a height finder of not less than an 8-meter basewillbe necessaryto meet the future demands of 3-inchand lOs-mm. antiaircraft gun batteries.

d. That the mean absolute error that may be expected ofthe best 4-meter base height finder is about seventy-fiye yards at an altitude of 4,000 yards.

It was recommended that the stereoscopic-typeheight finderbe adopted as standard.

In 19.32.Without the use of a method of calibration, the two height

finders give dependable readings only within the followinglimits:

T9 (4-meter) to a slant range of 2,500 yards.T12 (6-meter) to a slant range of 3,500 yards.

These values are based upon the hypothesis that the maxi-mum error in slant range allowedshould be 100yards.The best hope of successin developing an accurate heightfinder seems to lie in the field of the 2-station altimeter.

Small wonder then that a battery commander in thefield would refuse to use a stereoscopic height finder forhis annual target practice whenever he had an altimeteravailable. Small wonder also that he would devote verylittle time, if any at all, to endeavoring to train a satis-factory stereo observer.

However, the night is always the blackest just beforethe dawn. Be it everlastingly to the credit of that smallgroup of men who persisted in their efforts to develop asatisfactory height finder and to train competent observers,the picture now changes. The 1936 report of accuracy testsof height finders is very illuminating. Three differentmulti-station height finders were tested, including ourold standby the M1920 altimeter, together with twostereoscopic height finders, the T9E1 and the T16. A fewpertinent extracts of the report follows:Day Observation.

The T16 and the T9El, when operated by B>----were more accurate than any multi-station instrument.

Night Observation.The T9El operated by B , gave the most accurate

data of all instruments tested.1. The accuracy of the stereoscopic instruments, obtained

in this test by the most accurate observers, greatly ex-ceeded the accuracy obtained in the 1932 test.

2. The increase in accuracy of results, it is believed is dueprimarily to the use of more proficient observers.

In the 1936 tests, the MI920 altimeter was most con-sistently ranked last in accuracy. Occasionally, one of thestereo observers, who by our present-day standards couldnot be considered as properly trained, was less accuratethan the altimeter. No adverse comments appear in thereport as to the state of training of the altimeter operators,so it must be assumed that they were competent. As aresult of the 1936 tests, the Stereoscopic Height Finder,T 9E I, was standardized as the Stereoscopic Height find-er, 1\11, and is now being purchased in quantity.

Now that the stereoscopic height finder has been of-ficially recognized as a member in good standing of theantiaircraft fire control family, how is it being received?In one group, those of us who have enlarged our ac-quaintance by working and playing with it, think it is a"swell" instrument. Whenever it is available, we preferto work with it rather than the two-station altimeter. Ina second group are those who still prefer the two-stationaltimeter despite the proven superiority of the stereoscopicinstrument. In a third group are those who have yet tolearn about the stereoscopic instrument and its capabili-ties. What is being done about this? Well, nothing need

522 THE COAST ARTILLERY JOURNAL NO/Jember. December

Figure 2. StereoscoPic Training Del'ice

be done about the first group, as they like the stereoscopicinstmment and will spread the gospel far and wide. Forthe second group, nothing much can be done. For thethird group, a few are being introduced to it each year atthe Coast Artillery School with about fifteen hours of in-stmction and practical work as compared with aboutfifteen minutes of very perfunctory remarks some tcnyears ago. This is in addition to regimental schools forobservers in which a great deal of interest is being takenat the present time. What has made this extended intro-duction possible? Aside from the increased time madeavailable in the School curriculum, probably the biggestsingle thing has been the preparation and publication ofthe Coast Artillery School text "Stereoscopy and Stereo-scopic Range Finding." Although notes in fragmentaryform have been published previously, for the first timethe Coast Artillery Corps has available a reference textwhich covers the field of stereoscopic range finding in avery comprehensive manner and in language easily under-stood. The man responsible for the preparation of thistext unquestionably deserves another star in his crown,and will doubtless receive his reward upon arrival at thepearly gates. Figuratively speaking, he pick cd up the ballbehind his own goal line and ran with it all the way downthe field to the five-yard line where he was tackled andthrown by Deadline, the nemesis of authors and reporters.In this article, your reporter will endeavor to carry theball two yards farther, to the three-yard-line. Some repe-tition will be unavoidable and the ball may be fumbled

behind thc line of scrimmage, but maybe a vague point ortwo may be cleared up and maybe a helpful idea willappear. What follows is intended to supplement the ex-cellent text mentioned previously.

Without going into all the details in explanation ofwhy we can see stereoscopically, a simple but somewhatlengthy explanation, the reader is asked to accept the factthat everyone with two normal seeing eyes has stereoscopicvision. All that we need to be able to operate a heightfinder of the stereoscopic type is EXPERIENCE of the •proper kind, and the "stereoscopic frame of mind." SinceEXPERIENCE is KNOWLEDGE GAINED BYTRIAL, it is my firm conviction that the properly trainedstereoscopic observer does not depend upon his judgmentin measuring altitudes with a height finder, but rathercontinually works toward his own physiological limitof stereoscopic perception, and this limit can be actuall~'measured. It is now well established that of a group ofpersons with normal vision, we have every reason to ex-pect that about eighty per cent can become satisfactorystereoscopic observers, and of these, at least five per centwill be in the exceptionally proficient class.

Just how should we proceed to ferret out and utilizeall this latent ability? In what way may we add to the ex-perience of an individual to the end that he may acquirewhat has been called the "stereoscopic frame of mind"before he looks into a height finder? Fortunately, we areprovided with, or can provide oursel