'UNITED'SATS NAIR. FO~palASSISTANT CHIEF OF STAF,

STUDIES AND ANALYSIS,

AUGUST 1969.

.THE :IMPACT OF ALLIED, AIR INTER0iCTIONON'' GERMAN STRATEGY FOR NORMAND

S.ABER MEASURES (BRAVO,)

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THE IMPACT OF ALLIED

AIR INTERDICTION

ON GERMAN STRATEGY FOR NORMANDY.,

SABER MEASURES (BRAVO)

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Each transmittal of this document outside the Departmnt• ofDefense must have prior approval of---------------

Directorate of General Purpose and Airlift StudiesAssistant Cliief of Staff, Studies and Analysis

(. Headquarters, USAF

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FOREWORD

Over the past several years, serious doubts have

arisen among various analysts regarding the value of

interdiction attacks by US tactical air forces. In-

deed, conclusions have been reached in some quarters

that tactical air interdiction is hardly a worthwhile

military objective. Attempts have been made to sup-

port these conclusions through 'quantitative analysest

which have purported to demonstrate that interdiction

campaigns do not yield significant returns in rela-

tion to the effort and resources invested in them.

This study is an investigation of the value of

the interdiction campaign by Allied air forces during

the invasion of Normandy in June 1944. However, the

value of that interdiction campaign is not assessed

through Oquantitative analysis4, but rather through

the eyes of the German generals who endured it.

TABLE OF CONTENTS

FOREWORD

BACKGROUND . ... . .. .......... .1

GERMAN GENERALS COMMENT ON NORMANDY 0.... 4

Field Marshal Rommel's Scenariofor Normandy . .0. . . . . . . . . . . 4

General Speidel Outlines thevon Rundstedt Strategy ... ... . 6

Rommel Fears Allied Air Interdiction . . 7Events Justify Rommel's Fears, .0. . . . 10Von Rundstedt Strategy Caused

Costly Mistakes . .0. . . . . . . . . 13

REMARKS .0 . . . . . . . . . . . . . . . . . 17

DISTRIBUTION LIST .............. 19

BACKGROUND

The plan for the Allied invasion of the , .

continent (OVERLORD) in June 1944 included an air

offensive against transportation facilities supplying

the German defenses. Two principal objectives of

this offensive were: (a) to strain to the utmost the

enemy's capacity for carrying out railway movement by

the destruction of permanent installations, rolling

stock, and repair facilities, and (b) to disorganize

and, if possible, to stop military through-traffico

It wa&. understood that unless this was done, the rate

of the enemy's build-up in Normandy could easily ex-

ceed our own, and thus jeopardize any success which

our initial landings might achieve.

Prior to the invasion, Grrman generals them-

selves had differing estimates of Allied capabilities

for air interdiction. The differences of opinion

arose primarily between Field Marshals von Rirndstedt

and Rommel regarding defensive strategy and the de-

ployment of reserves in anticipation of the Allied

invasion. Rommel advanced the concept that the Ger-

man defensive forces must be deployed well forward,

close to the coast, because it would be difficult if

not impossible to commit them in time. He based his

theory upon experience with the effectiveness of Al-

lied air interdiction in North Africa and Italy.

Rundstedt, and other German generals who had never

experienced Allied air interdiction, did not agree

with this. They maintained that Rommel's theory was

a, militarily unsound departure from proven concepts

of defense in depth.

Rommel could never make them understand that de-

fense in depth, though theoretically sound, would be

strategically impossible against Allied air interdic-

tion. As he saw it, the one chance of successfully

defending the coast of Northern France in mid-1944

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would be to concentrate sufficient force for a quick

victory over an amphibious landing.

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GERMAN GENERALS COMMENT ON NORMANDY

Field Marshal Rommel's Scenario for Normandy

As early as 31 December 1943 in a report to

Hitler, Field Marshal Rommel outlined his scenario

for the Allied invasion:

. ° . The landing will probably be pre-ceded by very heavy attacks from the airand be made under cover of a smoke-screenand of intense fire from numerous war-ships, with simultaneous heavy-bomberattacks, . . Our defence line, thin as itis at present, will suffer severely fromthe enemy bombing and artillery bombard-ment and it seems very doubtful whether,after this battering, it will be capableof beating off the enemy. 0 . With thecoastline held as thinly as it is atpresent, enemy will probably succeed increating bridgeheads at several differ-ent points and in achieving a major pen-etration of our coastal defences. Oncethis has happened it will only be by therapid intervention of our operationalreserves that he will be thrown back intothe sea. This requires that these forcesshould be held very close behind thecoast defences.,

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If, on the other hand, our principalreserves have to be brought up from wellb., 'c inland, the move will not only requirea great deal of time .time which the enemywill probably use to reinforce himself athis point of penetration and either organ-ize his forces for defence or press theattack farther inland--but will also beunder constant danger from the air. . .British and American superiority in theair alone has again and again been so ef-fective that all movement of major forma-tions has been rendered completely impos-sible, both at the front and behind it, byday and by night, and our own air force hasonly on very rare occasions been able tomake any appearance in support of ouroperationso . .

o o o The Battle for the coast willprobably be over in a few hours and, ifexperience is any judge, the rapid inter-vention of forces coming up from the rearwill be decisive. One condition for thesuccess of this counter-attack by the re-serves will be for all available Luftwaffetactical air forces to support the attackand, above all, fight off the enemy bomberformations. :

1. Erwin Rommel (edited by Bo H. Liddell Hart), The

Rommel Papers, (New York, 1953) pp 453-456.

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General. Speidel Outlines the von Rundstedt Strategy

At Berchtesgaden on 1 April 1944, before assum-

ing his duties as Rommel's new chief of staff with

the Army Group, General Hans Speidel had asked for

instructions on strategy. In his post-war book he1

relates that:

Hitler and the High Command declaredthat any such directive was "superfluous."The Commander in Chief in the West and ArmyGroup B had strict orders that the coastwas to be rigidly defended; there was tobe no freedom for strategic operations. Incase of local landing, the enemy was to bedriven from the beaches back into thesea. 0..

The Commander in Chief for the West,Field Marshal von Rundstedt, thought alongthe strategic lines of the old school with-out taking into account the lessons of theRussian war and the Mediterranean campaigns,and without evaluating the battle tacticsof the British and Americans. He proposedto hold a small reserve south and east ofParis, from where it would be brought upafter an enemy landing. He thought thathe could thus retain freedom of action andmake full use of the former German super-iority in open warfare. This strategy would

1. Hans Speidel, Invasion 1944 (Chicago: Regnery,1950) pp 48-55.

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have been correct, had the German navaland air forces been equal., or nearly equal,in strength to those of the enemy. . 0

Rommel wanted to bring up the sixPanz. r divisions that were available andplace them close to the area where invasionwas expected. He remembered the lessonslearned from the landings in Italy. Large-scale local, landings could not be repulsedwithout these Panzer reserves. One or twoPanzer divisions would be no better than a"fire brigade," considering the lack oftransport facilities and the Allied airsupremacy0 . 0

As a minimum, five or six Panzer divi-sions within the Army Group command wouldbe required for 0 . 0 various tasks, andeven so '[t would be difficult for immobilecoastal defence forces without air or navalsupport to operate against a fully motor-ized enemy with crushing sea and airsuperiority.

Rommel Fears Allied Air Interdiction

Six weeks before the inv&sion Field Marshal

Rommel expressed his apprehension concerning the ef-

fects of Allied air interdiction on the mobility of

German forces, Ir. a letter of 23 April 1944, to

Colonel General Jodl, on Hitler's OKW staff, he wrote:

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My only real anxiety concerns the mo-bile forces. Contrary to what was decidedat the conference on the 21st March, theyhave so far not been placed under my com-mand. Some of them are dispersed over alarge area well inland, which means thatthey will arrive too late to play any partin the battle for the coast. With theheavy enemy air superiority we can expect,any large-scale movement of motorisedforces to the coast will be exposed to airattacks of tremendous weight and long dura-tion. But without rapid assistance fromthe armored divisions and mobile units, ourcoast divisions will be hard put to it tocounter attacks coming simultaneously fromthe sea and from airborne troops inland.Their land front is too thinly held forthat0 The dispositions of both combat andreserve forces should be such as to ensurethat the minimum possible move ent will berequired to counter an attack at any ofthe most likely points, whether in the LowCountries, in the Channel area proper, inNormandy or in Brittany, and to ensure thatthe greater part of the enemy troops, seaand airborne, will. be destroyed by our fireduring their approach.

Contrary to myself, General. Geyr vonSchweppenburg, 1 who may well know the Brit-ish in peacetime but has never yet met themin battle, sees the greatest danger in anoperational airborne landing deep inside

1. Commanding ist SS Panzer Corps

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France, and so wishes to be in a positionto mount a quick counteroperation. Hisforces have been located mainly with thatend in view. Furthermore, he does not wishto take his armoured divisions to an areabehind the land front of the coastal de-fences. . . I have disagreed very violentlywith General von Geyr over this questionand will only be able to execute my ideasif he i¶ put under Army Group command earlyenough.

Three weeks before the invasion, on 17 May 1944,

Rommel repeated his apprehensions concerning air in-

terdiction in a conversation with Lieutenant General

Fritz Bayerlein, one of his division commanders.

Stated Rommel:

Our friends from the East (German gen-erals with Russian Front experience) cannotimagine what they're in for heren It's nota matter of fanatical hordes to be drivenforward in masses against our line, with noregard for casualties and little recourseto tactical craft; here we are facing anenemy who applies all his native intelli-gence to the use of his many technical re-sources, who spares no expenditure ofmaterial and whose every operation goes itscourse as though it had been the subject of

1. Rommel Papers, pp 468-469.

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repeated rehearsal. It's obvious thatif the enemy once gets his foot in, he'llput every anti- tank gun and tank he can in-to the bridgehead and let us beat our headsagainst it, as he did at Medenine. To breakthrough such a front you have to attackslowly and methodically, under cover ofmassed artillery, but we, of course, thanksto the Allied Tir forces, will have nothingthere in time.

Events JustifX Rommel's Fears

Events proved that Field Marshal Rommel was cor-

rect in his analysis; fortunately for the Allies,

his warnings went unheeded. Air interdiction made

it impossible to bring the Panzer divisions from the

interior of France to the coast 0 They were broken up

in their detours before they could reach Normandy,

and the piecemeal forces that did arrive could not

immediately go into action without further reorgani-

zation. From the Field Marshal's report to Hitler on

1i Ibid., pp 467-468.

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10 June 1944, one can see the full impact of Allied

air interdiction on German resistance to the D-Day

invasion-

Under cover of his very strong airforce, the enemy is visibly reinforcing him-self on lane, and neither our air force norour navy is in a position, especially byday, to offer him any hindrance. Conse-quently, the enemy forces in the bridgeheadare growing at a considerably faster ratethan reserves are flowing to our front.Due to the enemy's air superiority, itproved impossible to bring ist SoS0 PanzerCorps, 7th Nebelwerfer Brigade, the A.A.Corps and the Corps "Meindl" up to the Orneand Vire fast enough to enable them tocounterattack the enemy forces after thelanding0 The Nebelwerfer Brigade, A. A0Corps and Corps "Meindl" are still on theway forward0 ist S.S. Panzer Corps hasbeen forced on the defensive in severefighting . 0

Our operations in Normandy are tremen-dously hampered, and in some places evenrendered impossible, by the followingfactors: (a) The immensely powerful, attimes overwhelming, superiority of theenemy force0 . During the day, prac-,tically our entire traffic --ou roads,tracks and in open country- ... is pinned downby powerful fighter-bomber and bomber for-mations, with the result. that the movementof our troops on the battlefield is almost

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completely paralysed, while the enemy canmanoeuvre freely. Every traffic defile inthe rear areas is under continual attackand it is very difficult. to get essentialsupplies of ammunition and petrol up to thetroops.

Even the movement of minor formationson the battlefield.-...artill.ery going intoposition, tanks forming up, etc.--is in-stantly attacked from the air with devast-ating effect. During the day, fightingtroops and headquarters alike are forced toseek cover in wooded and close country ino:cder to escape the continual pounding fromtthe air. On the 9th June, the situation inbattle area behind the S.S. Corps, was thatlarge numbers of enemy fighter-bomber squad-rons circled the battlefield continuously,while powerful bomberz formations dropped avery heavy weight of bombs on troops, vil-lages, bridges, and c-ossroads, withcomplete disregard for the civilian popula-tion. Neither our anti-•aircraft nor theLuftwaffe seems capable of imposing anycheck on the paralysing and destructiveeffect of the enemy air force (27,000sorties in one day). The troops,-Army andWaffen SoSo.-are putting up as good adefence as they can with the means availableto them, but ammunition is short and canonly be replaced under the most difficultconditions. . .2

1. Actually l-ess than 1'.1000,2. Liddell. Hart, The German. Generals Talk (New York:

Morrow, 1.948), pp 243-244o

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In commenting on the reduction of mobility caused

by air interdiction on 6 June 1944, General Gunther

Blumentritt, Chief of Staff under Field Marshals

von Rundstedt, von Kluge, and Model, in a post-war

interview described the situation to Liddell Hart:

The Corps artillery had been kept onthe east bank of the Seine..and the AlliedAir Forces had destroyed the bridges. TheField Marshal. and I had seen some of thembeing smashed. The artillery thus had tomake a long circuit southward by way ofParis before they could get across theSeine, and was repeatedly bombed on themarch, which caused more delays. As a re-sult two days passed before this reservewas on the scene, ready to strikeo1

Von Rundstedt Stratejaused CCost Mistakes

By the time that Rundstedt realized his mistake

in underestimating the power of Allied air interdic-,

tion, it was too late. After the war he stated to

Basil Liddell I-Tirt that after the first few days

1. Ibid., p 243.

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following the invasion he had no hope of victory

over the invaders,

The Allied Air Force paralyzed allmovement by day, and made it very difficulteven at night. They had smashed thebridges over the Loire as well as over theSeine, shutting off the whole area, Thesefactors greal.Jy delayed the concentrationof reserves there..-they took three or frurtimes lon er to reach the front than we hadreckoned. - .

Field Marshal Guenther von Kluge (another general

who had at first reje-cted Rommel's ideas) reported in

mid-July:

The enemy's command of the air restrictsall movement in terms of both space and time,and renders calculation of time impossible,For armoured or motorised troops in divi-sional strength upwards, it limits the pos-sibilities of command and manoeuvre to nightor bad weather operations, which cannot asa rule develop into anything more than op-erations with limited objective,2

Several. weeks after D,-Day, Rommel dispatched a

memorandum, on .5 July 1944, to Field Marshal. Guenther

von Kluge, the C-,in-,C (West). Pointing out how the

1. Ibid., pp 243-7,244.2. Rommel Pýa.ers., p 485.

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recommendations on deployment and command relations

had been disregarded, Rommel further depicts vividly

the frustrations caused by Allied air interdiction:

* o 0 Despite the existence of therailway network and sea routes, supplyconditions, especially in Normandy, werealready becoming difficult even before theinvasion, due to the heavy bombing of rail-way installationso . 0

The advance elements of 12th S.S. PanzerDivision Hitler Jugend, did not arrive inthe area north-west of Caen until 09.30hours on the 7th June, after a 75-mile ap-proach march, during which they sustainedsubstantial losses from low-flying aircraft.There being then neither the time nor thespace for a formation operation, its attackcould not be driven home 0

Panzer Lehr Division had 110 miles tocover, and its leading elements did not ar-rive at the battle front west of Caen until13000 hours on the 7th June0 They, too,were hindered in their advance by low-flyingaircraft, and the wheeled units became sep-arated from the tracked0 As a result, theirattack could no longer be put in; they were,in fact, hard put to it to maintain theirposition against the enemy, who had by thattime grown strong0 . 0

The leading elements of 2nd PanzerDivision, which had to be brought up fromits station on either side of the Somme

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(1.60 miles as the crow flies), arrived onthe 13th June. A further seven days wereneeded before it could go into action as adivision,

3rd Parachute Division required sixdays for its approach march from Brittanyto its battle area northeast of St. Lo (135miles as the crow flies), during which timeit was under constant threat from the air.By the time it arrived, the attack it wasdue to launch on Bayeux was no longer pos-sibleo . .

77th Division required six days beforeit could intervene with substantial forcesin the fighting in the north of the Cotentinpeninsula .

All the reserves that came up arrivedfar too late to smash the enemy landing bycounter-attacks. By the time they arrivedthe enemy had disembarked considerablystronger forces and himself gone over tothe attack under cover of powerful air andartillery support 0

Support by our air force was not forth-coming on the scale originally foreseen. Theenemy had command of the air over the bat-tleground up to a point some 60 miles behindthe front 0 In sorties of immense strengthhe smashed the defence installations in thecoastal zones and effectively opposed theapproach march of our reserves and the sup-ply of our troops, principally by damage tothe railway system.

1. Ibid., pp 481-484.

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REMARKS

While it may be possible to quantify the Allied

air interdiction efforts by listing number of sorties,

bomb tonnage expended, and the like, it 1s difficult

to see how an analyst could quantitatively predict

the outcome or assign numbers to the effects de-

scribed by the German generals in this study. From

their own experience these top strategists who de-

fended the Normandy beachhead in World War II were

able to clearly reveal what a major role air inter-

diction played in the failure of their strategy.

The initial success of OVERLORD, specifically

during the first few days, was due to the Allied air

interdiction effort. The fact that the Allied ground

forces could land, consolidate their positions, and

then go on the offensive before the German reinforce-

ments could reach the battle area, is highly indicative

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of the effectiveness of the Allied interdiction

campaign.

It is extremely doubtful that quantitativeahal-

ysis could measure the disruption caused by air inte'r-

diction which led to the failure of the German Army

to contain the Normandy invasion.

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