Blitz on Britain 1939-45 E-Book

Dr Alfred Price

• Herausgeber: The History Press
• Kategorie: Geisteswissenschaft
• Sprache: Englisch

Seitenzahl: 429

Veröffentlichungsjahr: 2016

Beschreibung

During the latter half of the 1930s, the fear of a possible aerial knock-out on Great Britain became a dominating factor in the formulation of national policy. This text examines how justified these pre-war fears were in light of the Luftwaffe's capabilities in 1939 and describes the bombing attacks on Britain during the years that followed, together with the operations of the defences to parry them. From the start, the air defences proved able to take a heavy toll on the bombers attacking Britain by day. By night it was a different matter. Initially, the fighter and gun defences were lucky if between them they were able to knock out one or two bombers out of three or four hundred involved in a night attack. From this poor beginning the defences improved out of all recognition and when the Germans launched a series of attacks on London early in 1944, it cost them one bomber and four trained crewmen for every five British civilians killed. Blitz on Britain makes compelling reading for anyone interested in the Luftwaffe's wartime raids on Britain, and how the air defences ultimately succeeded in defeating this long running aerial onslaught.

Leseprobe

BLITZ ON

BRITAIN

1939–45

The bombs have shattered my churches,

have torn my streets apart,

But they have not bent my spirit

and they shall not break my heart.

For my people’s faith and courage

are lights of London town

Which still would shine in legends though

my last broad bridge were down.

Greta Briggs, London Under Bombardment

Other books by the same author

Instruments of Darkness

Battle of Britain The Hardest Day, 18 August 1940

Battle of Britain Day, 15 September 1940

The Spitfire Story

Spitfire at War (three volumes)

Battle Over the Reich

Aircraft versus Submarine

Last Year of the Luftwaffe, May 1944 to May 1945

Luftwaffe Data Book

Sky Battles

Sky Warriors

Focke Wulf 190 in Combat

Luftwaffe in Camera (two volumes)

The History of US Electronic Warfare (two volumes, with third in preparation)

Books co-authored with the late Jeff Ethell

Target Berlin, USAAF Mission 250, 6 March 1944

World War II Combat Fighting Jets

One Day in a Long War, Air Action over North Vietnam, 10 May 1972

Air War South Atlantic, 1981

BLITZ ON

BRITAIN

1939–45

ALFRED PRICE

First published in 2000

This edition first published in 2009

The History Press

The Mill, Brimscombe Port

Stroud, Gloucestershire, GL5 2QG

www.thehistorypress.co.uk

This ebook edition first published in 2016

All rights reserved

© Alfred Price, 2000, 2009

The right of Alfred Price to be identified as the Author of this work has been asserted in accordance with the Copyrights, Designs and Patents Act 1988.

This ebook is copyright material and must not be copied, reproduced, transferred, distributed, leased, licensed or publicly performed or used in any way except as specifically permitted in writing by the publishers, as allowed under the terms and conditions under which it was purchased or as strictly permitted by applicable copyright law. Any unauthorised distribution or use of this text may be a direct infringement of the author’s and publisher’s rights, and those responsible may be liable in law accordingly.

EPUB SBN 978 0 7509 7932 0

Typesetting and origination by The History Press

eBook converted by Geethik Technologies

Contents

Prologue

1 More Worry than War, September 1939–June 1940

2 Battle is Joined, June–August 1940

3 Striking at the Airfields, 11 August– 6 September 1940

4 The Attack on London and After, 7 September–1 November 1940

5 Death by Darkness, August 1940–May 1941

6 Fairly Quiet on the Western Front, June 1941–December 1942

7 In Fits and Starts, January–December 1943

8 ‘Steinbock’ and After, December 1943–March 1945 179

Bibliography

Appendices: A. RAF and Luftwaffe Units

B. Comparative Ranks

C. Fighter Command Tactical Memorandum No. 8, June 1940

D. ‘Battle of Britain Day’ – the German View

E. Operation ‘Steinbock’, 1944 – Goering’s Order

F. Luftwaffe Units Committed to Operation ‘Steinbock’, 20 January 1944

G. Attack on London, 23 February 1944

The author with Generalmajor Dietrich Peltz, who directed the air attacks on Britain during 1943 and 1944, seen here in 1975 while this book was being researched.

Prologue

My intention in writing this book has been to describe the bomber attacks on Great Britain between 1939 and 1945 and the operations of the defences to counter them. For reasons of space I have omitted more than passing references to the other forms of bombardment during this period: the ground-launched V1s, the V2s and the German long-range guns that fired across the Channel. I have made no attempt to mention every single bomber attack. Instead, I have selected actions I consider to be representative of the period covered by each chapter, and concentrated my attention on two of these. In the case of the Battle of Britain, for example, I endeavoured to show in detail what happened on two days, 18 August and 15 September 1940.

Blitz on Britain would not have been possible without the wholehearted co-operation of many people both in Britain and in Germany. From the Royal Air Force, Air Chief Marshal Sir Hugh Saunders, Air Commodore ‘Toby’ Pearson, Group Captain R. Oxspring, Group Captain R.C. Haine, Prince Emanuel Galitzine and Mr D. Hayley-Bell; from the Luftwaffe, General Major Dietrich Peltz, General Roderich Cescotti, Oberst Horst von Riesen and Horst Goetz, Erich Sommer, Adolf Dilg, Helmut Wenk, Rudi Prasse, Otto Schmidt, Wilhelm Raab and Guenther Unger. Also many good friends have generously lent me material and photographs, in particular Hanfried Schliephake, Wolfgang Dierich, Jim Oughton, Franz Selinger, Derek Wood and John Taylor. Peter Cornwell and A.K. Stone have provided invaluable advice on the manuscript.

I am indebted to the staffs of the Air Historical Branch, the Public Record Office in London and the Bundesarchiv in Freiburg for much of the information used in this book. I am also grateful to the Imperial War Musuem, the Bundesarchiv Bildarchiv at Koblenz and Herr Walter Brieke, the keeper of the Kampfgeschwader 76 Archive, for the use of photographs. Thanks are also due to Peter Elstob for permission to use his graphic account of the bombing of London.

The first edition of this book appeared in 1977, before the release of detailed information on the decrypts by the code-breakers at Bletchley Park. This revised account covers this aspect of the story in so far as it affected the RAF intelligence picture on Luftwaffe units operating against Britain.

Also during the twenty-two years since the publication of the first edition, new information on the Battle of Britain and later attacks has become available to the author. This material is also included in this revised and expanded edition.

In this book, where applicable, dimensions have been translated into British units, rounded up or down if appropriate. Times have been adjusted to GMT.

Alfred Price

Rutland

December 1999

Line-up of Spitfires of No. 19 Squadron at Duxford, May 1939.

CHAPTER 1

More Worry than War, September 1939–June 1940

In approaching the prospects for a successful air campaign either against Great Britain alone, or against both Great Britain and France, there is one conspicuously favourable factor which will tend to influence Germany’s judgement and encourage her to hope for success, and that is the exposed position and vulnerability of London . . . France offers to German attack no such favourable objective. Nothing that either France or ourselves can attack in Germany can have quite the immediate and decisive results that Germany may hope to gain by an overwhelming attack on London.

Marshal of the Royal Air Force Sir Edward Ellington, Chief of the Air Staff, speaking before the war

At 11.45 a.m. on Sunday 3 September 1939, Prime Minister Neville Chamberlain began his sombre broadcast to the British people:

This morning the British Ambassador in Berlin handed the German Government a final note stating that unless we heard from them by 11 o’clock that they were prepared at once to withdraw their troops from Poland, a state of war would exist between us. I have to tell you now that no such undertaking has been received, and that consequently this country is at war with Germany. . . .

The Prime Minister spoke for about a quarter of an hour, during which time he stressed that he had done all he could to maintain peace but Hitler would have none of it.

Within minutes of the end of Mr Chamberlain’s speech, air-raid sirens sounded their warbling note through London and several other cities in Great Britain. For the citizens the prospect of air attack so soon after the outbreak of war came as no great surprise. For almost a decade previously there had been a stream of writers and speakers predicting, in the most grisly terms, the effects of the aerial ‘knock-out blow’ which they felt would mark the opening of any future world war.

THE FEARED KNOCK-OUT BLOW

It is the task of military planners to calculate ‘worst case’ scenarios for what might happen if an enemy launched different forms of attack. However, if planners run two or more ‘worst case’ scenarios together in series, the resultant prognosis can be truly dreadful. This was the case when, before the war, they had calculated the number of casualties to be expected from an all-out German air attack on Britain.

The pre-war estimates of the weight of bombs the German bomber force could put down on British cities, and in particular London, varied greatly. In December 1938, during a speech intended to justify the appeasement of Hitler, the Lord Chancellor had stated that ‘The Germans had it in their power to let loose 3,000 tons of bombs in a single day.’ Writing shortly afterwards in his book The Defence of Britain the respected commentator Liddell Hart stated, more cautiously, that the weight of bombs German bombers could carry in a sustained offensive on Britain amounted to about 600 tons per day, yet:

The seriousness of that threat can be gauged by comparison with the fact that during the whole of the last war only 74 tons of bombs were dropped on England by hostile aeroplanes. That quantity, dispersed in time and space, killed 857 people, wounded 2,058 and caused material damage which in monetary cost amounted to approximately £1,400,000. On such a basis of comparison, nearly a quarter of a million casualties, and over £100,000,000 worth of damage, might be anticipated in the first week of a new war.

In the spring of 1939 the British Air Staff put the German long-range bomber strength at about 1,600 aircraft. It was estimated that over the first two weeks of a future war this force could deliver about 700 tons per day on London, with the weight of the attack tapering thereafter. Using slightly different figures to those employed by Liddell Hart in his calculation, they produced a ‘worst case’ casualty figure of fifty people killed or wounded for each ton of bombs dropped on a built-up area. Taking both of these ‘worse case’ figures together, Ministry of Health officials calculated that during the first six months of an aerial bombardment there would be 600,000 people killed and 1,200,000 wounded. It was a daunting prospect. To what extent were the fears justified?

From the German records we know that on 2 September 1939 the Luftwaffe possessed 1,180 twin-engined bombers with the range to attack targets in England from airfields in Germany (about a quarter less than the British Air Staff’s ‘worst case’ estimate) of which 1,008 were serviceable. The bulk of the bomber force, nearly 800 aircraft, was made up of Heinkel 111s; some 750 were the latest H and P sub-types, while the remainder were obsolescent variants. Virtually all the remaining twin-engined bomber units were equipped with the Dornier 17, either in its modern Z sub-type form or earlier models. From airfields in north-western Germany to London meant a round trip of 760 miles flying round Holland, or 720 miles flying over it. The maximum bomb load of the Heinkel 111 was 4,400 pounds and that of the Dornier 17 was 2,200 pounds. The British Air Staff, lacking exact performance figures for the German bombers, had credited both types with the ability to carry their full bomb loads to London from airfields in Germany. In fact, with an operational allowance of fuel to allow for formation assembly, route flexibility and a safety margin in case aircraft had to be diverted, neither type could attack London with its full load of bombs.

Early production Heinkel 111, the J variant. At the beginning of 1939 several versions of this bomber were in service and they made up more than half the twin-engined bomber strength of the Luftwaffe.

Thus 400 tons per day – not 700 tons – was nearer the maximum the German bomber force could carry to the British capital as a sustained daily average. Allowing for strays and bombs that failed to explode, the figure fell to a realistic maximum of about 300 tons of exploding bombs on the target for a maximum effort daylight attack and 100 tons for a similar attack at night (when the proportion of stray bombs would have been substantially greater).

The weight of bombs the Luftwaffe could put down on London had been greatly exaggerated; yet this over-estimation was dwarfed by the parallel over-estimation of the effect these bombs might have. The ‘fifty casualties per ton’ rule was based on official British figures issued after the German bombing attacks during the First World War. But during these attacks the German bombers had carried a considerably greater weight of bombs than those known to have exploded, which were chronicled in British records. In fact about 110 tons had been carried, which meant that the figure of 74 tons quoted by Liddell Hart was too low by about one-third. Actually, the number of casualties per ton of bombs carried to urban areas in Britain during the First World War was about twenty-six. This alone made the Air Staff ‘worst case’ estimate in error by almost as much again. Moreover, the First World War figures of ‘casualties per ton’ had been grossly distorted by a few ‘lucky’ hits before there was a proper warning system or provision of shelters. During the first aeroplane attack on London, by 17 Gotha bombers on 13 June 1917, 162 people had been killed and 432 injured by a total of only 4½ tons of bombs, some of which failed to explode. This meant an average of 132 casualties per ton. During the early Gotha raids many people had been standing in the streets, gawking at the enemy planes flying above, when they were killed or wounded. Once the public learned the folly of such behaviour, air-raid casualties fell dramatically.

Hurricanes of No. 111 Squadron refuelling at Wick, early in the war. This type equipped the majority of RAF fighter squadrons during the first year of conflict. (IWM)

THE DEFENDERS’ RIPOSTE

So much for the predicted weight of attack on Britain, and the actual weight the Luftwaffe was capable of delivering. Now let us examine the ability of the air defences to parry an attempted ‘knock-out blow’.

In September 1939 RAF Fighter Command possessed a total of 747 aircraft in 39 front-line squadrons, with about 400 aircraft in reserve. This figure was split as follows (reserve aircraft in brackets): Hawker Hurricane, 16 squadrons with 347 aircraft (22); Supermarine Spitfire, 10 squadrons with 187 aircraft (71); Gloster Gauntlet, parts of 2 squadrons with 26 aircraft (50); Gloster Gladiator, 4 squadrons with 76 aircraft (126); Bristol Blenheim, 7 squadrons with 111 aircraft (about 40). The newer German bomber types could attain brochure maximum speeds of about 250 mph, but flying at this pace guzzled fuel and it was rarely used in normal war operations. Usually, the need to conserve fuel and maintain formation meant bombers cruised at speeds of about 180 mph. They were, therefore, within the interception capability of even the slowest British fighter types.

The most modern of the British fighters, the Spitfire and the Hurricane, were armed with eight .303 inch Browning machine guns; the older Gladiator carried four of these weapons and the Blenheim carried five (plus a sixth gun in the rear turret for self-defence). The rifle-calibre Browning fired ball, incendiary or armour-piercing rounds, each weighing just under half an ounce, at a rate of 1,150 per minute per gun. This fast-firing weapon was very effective against unarmoured aircraft (at the outbreak of the war German bombers did not carry armour). The Gauntlet carried an obsolescent armament comprising two slow-firing Vickers guns and would have been ineffective against German bombers; at the outbreak of war this fighter was on the point of going out of front-line service.

The Commander-in-Chief Fighter Command, Air Chief Marshal Sir Hugh Dowding, calculated that a minimum of 46 squadrons with 736 fighters would be necessary to defend the spread of targets from Portsmouth to the Clyde from air attack on the scale expected. By ‘defend’ he meant the ability to inflict a loss rate of 13 per cent of the raiding force for each attack, a rate of attrition no air force could accept during a protracted offensive.

Dowding’s figure of forty-six squadrons was a realistic minimum requirement to defend Great Britain from the size of attack he had been told to expect. In fact, when war broke out, he had not forty-six squadrons but thirty-nine. And of the latter, four were dispatched to France soon afterwards. This meant Dowding’s force was below strength by about one-quarter. But because the British intelligence estimate of the strength of the German bomber force was exaggerated by a similar amount, the number of fighters available in the summer of 1939 can be considered sufficient to inflict unacceptable losses on any attack the Luftwaffe could have mounted from bases in Germany.

To attack Britain from bases in Germany, the bombers would have to operate far beyond the reach of any fighter escort. In the light of what happened subsequently, there can be little doubt that even the small number of fighters available would have been capable of dealing severely with any attempt in September 1939 to mount an aerial ‘knock-out blow’ on London or any other target in Britain by day. Lacking adequate radar, British fighters were virtually ineffective by night. But by night the bombers, too, would have found it difficult to locate targets and the weight of attack would be greatly reduced.

FIGHTER COMMAND’S ‘SYSTEM’

The fighters were the ‘teeth’ of Fighter Command. But scarcely less important were the ‘eye’ and ‘brain’ organisations, and the ‘nervous system’ to carry information between the three, to position the ‘teeth’ to snap at the enemy to greatest effect.

Before the war British scientists had hurriedly prepared for service a chain of rudimentary radar stations which, by the summer of 1939, was able to detect aircraft approaching at medium or high level at a distance of about 100 miles. These stations were Fighter Command’s long-range ‘eyes’. When war came there were eighteen radar stations, code-named Chain Home (CH), in operation giving cover along the eastern and southern coasts of Britain between Portsmouth and Aberdeen. (The term ‘radar’ was not coined until after the American entry into the war in 1941; but because of its universal use now, it is used in this account rather than RDF – Radio Direction Finding – which was in use at that time.) To see how this radar information was used, let us follow a typical engagement of a ‘raiding force’, as practised during the Fighter Command exercises just before the war.

The Chain Home radar stations, erected along the eastern side of Britain immediately before the war, were Fighter Command’s long-range ‘eyes’. These stations could plot aircraft flying more than 100 miles away, at medium or high altitudes. The transmitting aerials were strung between four 350-foot high towers. The transmitter was housed in the camouflaged building in front of the base of the centre tower.

Interior of the Chain Home radar receiver room.

The first sign of the approach of the ‘enemy’ was usually from one of the coastal radar stations. The grid position, altitude and estimated strength of the incoming force were passed by landline to the Filter Centre at Fighter Command Headquarters, at Bentley Priory near Stanmore. There filter officers checked the plots against the known movements of friendly aircraft. The plots, treated as ‘hostile’ until identified, were passed to the Fighter Command operations room and by landline to the Group and Sector operations rooms dotted round the country. The controller at the Group operations room was responsible for ordering off fighters to meet any hostile incursion likely to enter his Group’s area. As the ‘raiders’ neared the coast, he allocated responsibility for controlling the engagement to the fighter Sectors. The headquarters at Bentley Priory, and the Group and Sector operations rooms, were the ‘brains’ of Fighter Command. The plethora of landlines linking all of them with the radar stations and observer posts constituted the ‘nervous system’.

Once fighters were off the ground, they were the responsibility of the Sector controller directing the interception. He ordered the fighters to the raiders’ altitude, and passed a stream of vectors to bring about an interception. To enable the Sector controller to keep track of his fighters, one pilot in each formation of fighters switched his radio to ‘Pip-Squeak’. This automatically switched his transmitter on for 14 seconds in each minute, during which the three ground direction-finding stations in each Sector took bearings on the signals. The bearings were passed to the Sector operations room, where they were correlated to give a fix on the fighters.

The plots on aircraft approaching the shores of Britain were passed direct from the radar stations to the Filter Room at Stanmore, seen here. In this room the plots were checked against the known movements of friendly aircraft; plots on unidentified and hostile aircraft were then passed to the Group and Sector operations rooms, from which the air battles were controlled.

The author standing outside the No. 11 Group fighter control bunker at RAF Uxbridge, open for public viewing.

The plotting table at No. 11 Group headquarters, with the WAAF staff moving blocks representing units into place.

Fighter controllers’ positions at No. 11 Group headquarters, viewed from the plotting table.

Once a raiding force had crossed the coast of Britain it was usually out of view of the Chain Home radar stations. For overland plotting during the initial part of the war Fighter Command depended entirely on the network of posts manned by the Observer Corps. The post seen here was situated on the roof of the Senate House at London University. (IWM)

As the ‘raiding force’ neared the coast it came within a view of the Observer Corps posts, situated at 5-mile intervals across the southern and eastern part of the country. These were Fighter Command’s short-range ‘eyes’. The individual posts passed to their own Group operations rooms details of the position and estimated height and heading of the incoming force, together with an indication of the numbers of aircraft and, usually, their types. The Observer Group Headquarters would relay this information to the fighter Group and Sector operations rooms, where it was used to update the air picture. As the ‘raiding force’ moved inland it was tracked by the Observer Corps, since the radar stations were sited to look only out to sea.

When the leader of the fighter formation sighted the ‘enemy’ he called ‘Tally Ho’, indicating that he was taking control of the engagement and required no further help from the ground. Once the interception was complete, the Sector controller passed the fighters’ vectors to take them back to their base or, if this was no longer usable, to a suitable airfield.

By the outbreak of war the Fighter Command control and reporting system, with its chain of radar stations and ground observer posts, was just about ready. During the final air exercises in peace its value had been proved. However, the acid test of actual combat remained.

AA GUNS AND SEARCHLIGHTS

For the close defence of potential targets in Britain, in September 1939 the Army Anti-Aircraft Command operated a total of 425 modern heavy guns (out of a requirement of 2,232) and 253 light guns (out of a requirement of 1,860). Thus the anti-aircraft gun defences had less than one-fifth of the weapons considered necessary for their task.

The backbone of the British anti-aircraft gun defences against high-flying raiders in 1939 was the 3.7-in gun, seen here in its mobile version; this weapon could fire a maximum of ten 28-pound shells per minute. Normally it was fired from a revetted position but in this posed photograph, taken shortly before the war, it is seen in the open with its range-finder (centre) and predictor (left). (IWM)

The purpose of ground anti-aircraft fire was three-fold: first, to destroy or damage hostile aircraft; secondly, to assist in breaking up enemy formations so that fighters could engage more effectively; and thirdly, to reduce bombing accuracy by forcing aircraft to attack from high altitude. Although they were rarely successful in securing the first two of these objectives, strong gun defences were to prove consistently successful in bringing about the last of them.

The heaviest type of anti-aircraft gun in service at the beginning of the war was the 4.5-in, which could fire a maximum of eight 55-pound shells per minute. (IWM)

The modern heavy anti-aircraft weapons in service in the British Army in 1939 were of two types, the 3.7-inch and the 4.5-inch. The 3.7-inch fired 28-pound shells at a maximum of ten per minute to an effective engagement ceiling of 25,000 feet. On exploding, the splinters from the time-fused shell were lethal against aircraft within about 15 yards. The 4.5-inch gun fired 55-pound shells at a maximum of eight per minute to an effective engagement ceiling of 26,000 feet and was lethal against aircraft up to about 20 yards from the point of detonation. In addition there were 270 of the lower performance 3-inch guns, a First World War weapon with an effective engagement ceiling of 14,000 feet.

Lacking radar for the detection of bombers coming in at night or above cloud, during the first year of the war the gunners had to rely on acoustic sound locators. (IWM)

Heavy anti-aircraft guns were usually deployed in groups of four. However, sites with two, six or even eight guns were not uncommon. Each site had its own range-finder and predictor. To engage aircraft with heavy anti-aircraft guns, accurate prediction was essential. Fired at an aircraft flying at 17,000 feet, a 3.7-inch shell took about 10 seconds to reach the target; but during that time a bomber moving at 180 mph covered half a mile. Thus the gunners needed to aim their weapons at, and fuse their shells to explode in, a position 880 yards in front of the target’s observed position.

There were two prediction devices in service in the British Army at this time, the Vickers and the Sperry. An analogue computer in the predictor calculated, from information on the aircraft’s previous flight path, where it would be at the time the shells reached it. It then disgorged this information, in the form of azimuth and elevation settings for the guns and time-flight fuse settings for the shells. This information was passed electrically to the individual guns, whose crews tracked the predicted position of the target, fused the shells and fired their weapons by salvoes on the orders of the site commander. Of course, the bomber crew could easily upset the gunners’ aim by flying a weaving path. But the guns were sited to cover the approaches to the targets and any ‘jinking’ during the bombing run usually resulted in bombs landing well clear of the aiming point. The prevention of accurate bombing, it will be remembered, was one of the purposes of anti-aircraft fire.

By night the aircraft were picked up first by sound locators, which assisted searchlights to find and illuminate the target. With the aircraft thus in view, the optical fire-control devices could track it and the engagement could take place as by day. The standard type of searchlight in service at the beginning of the war was the 90-cm, with a carbon projector giving 210 million candle power. Apart from assisting guns and fighters to locate targets at night, the searchlight constituted an effective defence in its own right: by dazzling enemy bomb aimers it could obscure the target. And it could have a profound morale effect on enemy crews simply by rendering their aircraft conspicuous, even if there were no fighters or guns immediately available to engage.

For defence against low-flying raiders, Anti Aircraft Command employed the 40-mm Bofors gun, which fired at a maximum rate of 120 2-pounder shells per minute. Although a formidable weapon, the Bofors was in critically short supply during the first year of the war. (IWM)

At the outbreak of war the gunners’ sole method of detecting bombers at night was by means of sound locators. By collating the angles from two or more locators, it was hoped to work out the present and future positions of individual raiders accurately enough for the guns to engage. The main problem with sound locators, however, was that by the late 1930s their capability had been outstripped by the modern bomber. At the locator’s maximum range of 6,000 yards, aircraft engine noises took 18 seconds to reach the instrument. Thus, if the aircraft was moving at 180 mph, the bearing found by the locator lagged the position of the aircraft by about a mile. During peace-time trials the locators seemed to provide a moderate chance of engaging unseen bombers with predicted fire. It was, in any case, the best that could be done with the equipment available.

For the defence of targets against low-flying aircraft there was the 40-mm Bofors gun, an excellent weapon that fired 2-pound impact-fused high-explosive shells at a maximum rate of 120 per minute. The gun had an effective engagement ceiling of 12,000 feet. The Bofors could be fired over open sights or, with greater accuracy, using a simple predictor. In 1939 the only thing to be said against the Bofors was that there were hardly any of them: a mere 253 were deployed at the beginning of the war, compared with a requirement of 1,860 for the defence of targets in Britain.

BARRAGE BALLOONS

The final element of the defence was the barrage balloon, of which a total of 624 were available at the beginning of the war out of a requirement of 1,450. The balloon was designated the LZ (Low Zone); just over 62 feet long and 25 feet in diameter at its widest part, it had a hydrogen capacity of about 19,000 cubic feet. The LZ balloon was flown from a mobile winch and was designed for a maximum flying altitude of 5,000 feet.

A barrage balloon supporting a mile of cable anchored to the ground did not constitute a lethal obstacle to aircraft in service in the late 1930s. At impact speeds of 2,000 mph and greater, the shock of the collision was usually sufficient to sever the cable without causing undue damage to the aircraft. Immediately before the war govern-ment scientists examined several methods of making balloon cables lethal. One of these, the so-called Double Parachute Link, was considered effective and put into production (see diagram on p. 14). During a trial with the Double Parachute Link a Wellington bomber struck the cable with one wing and the system worked according to plan. Unfortunately, however, the safety cutters failed to sever the cable before the parachutes were fully deployed. The resultant yawing load on the aircraft was so great that the fuselage broke midway along its length. The Double Parachute Link system went into service towards the end of 1939 and by mid-1940 the majority of the LZ balloons had it.

A barrage balloon flying from the grassed area immediately to the south of the Houses of Parliament.

To provide protection from low-level attack, a barrage of 450 balloons was required for a target the size of London. With balloons positioned randomly over the area at a density of nine per mile there was a one-in-ten chance of an aircraft with a wingspan of 60 feet striking one of the cables.

Although the LZ balloon was designed to operate in winds of up to 60 mph, the weather was to prove a continual hazard to these ungainly gasbags. On 15 September 1939, for example, an unexpectedly severe electrical storm caused the destruction of 78 balloons in the London area before the remainder could be pulled to safety.

In September 1939, although there were insufficient anti-aircraft guns and balloons, the British air defences as a whole would have been capable of inflicting a heavy cumulative loss on bombers making repeated daylight attacks without fighter escort. Taking all factors into account, it is clear that it was beyond the German capability to sustain the feared aerial ‘knock-out blow’ at the beginning of the war. Winston Churchill later noted that before the war governments had been greatly misled by gory tales of the death and destruction to be expected from air raids: ‘This picture of aerial destruction was so exaggerated that it depressed the statesmen responsible for the pre-war policy, and played a definite part in the desertion of Czechoslovakia in August 1938.’ So we now know that in September 1939 the Germans lacked the means to deliver the ‘knock-out blow’ against Britain; but did they ever intend to try?

In air defence few things are as simple as they might appear at first glance. When it was armed with the Double Parachute Link, the LZ balloon was no exception. When an aircraft struck the cable, the latter was severed at the top and the bottom by two cutting links. The aircraft thus carried away the main portion of the cable and an 8-foot diameter parachute opened at each end of the wire. Together the parachutes exerted a drag about six times as great as the engine thrust of a bomber, sufficient to stop it almost dead in its tracks. The aircraft then fell out of the sky and crashed. As the cable parted from the balloon, a wire ripped off a patch which allowed the hydrogen to escape; the balloon then descended slowly to the ground.

THE GERMAN INTENT

From German records there is clear evidence that Hitler had no intention of mounting a ‘knock-out blow’ against Britain early in the war, although he extracted the maximum diplomatic mileage from the threat of such attacks during the final year of peace. Until the war in Poland had been brought to a successful conclusion his bomber force would be required there. And when Poland had been defeated it might be possible to present the Western Allies with a fait accompli and, having achieved his immediate aims, secure peace. Either way, he felt there was little to be gained from unleashing his bombers against Britain at that stage.

Later, strategic bombing attacks on Britain might be necessary. Hitler wished to keep this option open. At the end of the top-secret ‘Directive No. 1 for the Conduct of the War’, dated 31 August 1939, the Fuehrer stated:

Any favourable opportunity of an effective attack on concentrated units of the English Navy, particularly on battleships or aircraft carriers, will be exploited. The decision regarding attacks on London is reserved to me. Attacks on the English homeland are to be prepared; though it should be borne in mind that inconclusive results, due to the use of insufficient forces, are to be avoided in all circumstances.

During the months that followed, Hitler would reiterate his refusal to allow air attacks on civilian targets in Britain. For the time being the cities would remain inviolate. Yet the threat was ever-present, and vigorous steps were taken to strengthen the defences.

The ‘raider’ that had caused the sirens to wail in London at midday on the first day of war was, it soon became clear, a civil aircraft coming in from France; shortly afterwards, the ‘All Clear’ was sounded. There was a similar false alarm on the following day, 4 September.

THE ‘BATTLE OF BARKING CREEK’

At 0630 hours on the morning of 6 September there were signs that, at last, the Germans really were coming in force. The Chain Home radar station at Canewdon near Southend began passing plots on a force of some twenty aircraft approaching the Thames Estuary from the east. When both Bomber and Coastal Commands reported they had no aircraft operating in this area, the Fighter Command Filter room designated the force ‘Hostile’. At 0645 hours a preliminary warning was issued and fighters were scrambled. During the next few minutes the number of separate ‘Hostile’ forces being plotted rose from five to twelve, each with between ‘six plus’ and twelve aircraft. By 0650 hours the incoming force was plotted heading up the Thames, giving all the indications of a massed attack on London. Air-raid warning ‘Red’ was issued. In London, the sirens wailed for the third time since the beginning of the war.

By 0655 hours No. 11 Group had seven flights of fighters airborne, either in or making for the Thames Estuary. No. 12 Group was warned that it might also be required to provide fighters to reinforce the defences of the capital. An anti-aircraft gun site near Clacton reported it was engaging enemy twin-engined aircraft. Shortly afterwards Spitfires of No. 74 Squadron gave a ‘Tally Ho’ call and went into action.

It was nearly an hour before the air situation over the Thames Estuary was finally resolved. And when it was, it became clear that the Luftwaffe had been nowhere in the area. By the time the so-called ‘Battle of Barking Creek’ reached its inglorious conclusion, the Royal Air Force had lost three aircraft destroyed and one pilot killed. The ‘twin-engined aircraft’ engaged by the anti-aircraft gunners turned out to be Blenheim fighters of No. 64 Squadron, one of which was shot down. The ‘enemy aircraft’ engaged by No. 74 Squadron turned out to be Hurricanes of No. 56 Squadron, two of which were shot down.

The root cause of the ‘battle’ had been a technical fault at the radar station at Canewdon. As a result, echoes from aircraft flying to the west of the radar in the ‘back beam’ were not filtered out. Instead, they appeared on the screen looking exactly like those from aircraft approaching the radar station from the east. As more fighters had taken off to engage, their echoes added to those of the phantom raiding force which became progressively larger. Once the existence of the ‘raiding force’ was established in everyone’s mind, the misidentifications and shooting were only to be expected from a defensive system inexperienced in war and over-quick on the trigger. It was the first time that friendly aircraft were mistaken for ‘hostiles’ on a radar screen and it would certainly not be the last. The problem of differentiating between friend and foe in a confused aerial situation remains to this day. The report of the subsequent inquiry stressed the need for far greater care before aircraft were identfied as ‘hostile’. And the production of radar Identification Friend or Foe (IFF) equipment for RAF aircraft was to be given the highest priority.

During the weeks that followed the ‘Battle of Barking Creek’ the false alarms became far less common. And the British people lacked even this diversion to remind them they were at war. After what had been said during the previous decade, there was a clear feeling of anticlimax.

During the first months of the war, the matter of crossing a road in the black-out constituted a far greater hazard to the citizens of Britain than anything caused by the Luftwaffe. As this government-sponsored advertisement shows, there were nearly 1,200 road deaths during December 1939 alone; this was more than four times the monthly average for 1999, when a vastly greater number of vehicles was on the roads.

EFFECTS ON CIVILIAN LIFE

In the event, the institution of the pre-war contingency plans to meet the expected ‘knock-out blow’ had a far greater effect on people’s lives than the war itself during this period. The scheme to evacuate the young and the sick from the cities went ahead. From London alone, the exodus involved more than 650,000 schoolchildren and teachers, very young children and mothers, expectant mothers and invalids. The migration to the countryside was conducted swiftly and, considering the scale, more or less efficiently. Yet, in the absence of the feared air attacks, the will to remain away from home quickly dissipated. As early as mid-September, only two weeks after the outbreak of war, Minister of Health Walter Elliot found it necessary to appeal to mothers not to return: ‘The fact that up to the present no air raids have taken place in the large towns does not affect the position.’ This injunction fell on deaf ears, and during the months that followed there was a steady drift homewards. By the end of the year about a third of the schoolchildren and most of the very young children and mothers had returned.

Spitfires of No. 19 Squadron flying in the tight formation of vics employed early in the war.

If the evacuation scheme was considered by many an unnecessary irritation that could be put right, the same could not be said of the effects of the black-out. With the street lights extinguished and cars restricted to driving with just sidelights, during the closing months of 1939 road casualties in Britain accounted for far more deaths than the sporadic fighting. By the end of December 1939 more than 4,000 people had been killed, about a third more than in the same period in 1938. This was in spite of the fact that half a million cars had been laid-up by mid-December due to the imposition of petrol rationing. So long as it existed, the black-out was to make night-time travel a serious hazard for motorist and pedestrian alike.

FIGHTER COMMAND TACTICS

Of course, Air Chief Marshal Dowding had no way of knowing that Hitler did not intend to launch the expected ‘knock-out blow’ soon after the outbreak of war. And the very speed of the Blitzkrieg in Poland had demonstrated the ability of the German Army to undertake rapid thrusts deep into enemy territory. This undermined the comfortable assumption that a German aerial bombardment of Britain would be made only by unescorted bombers. In November 1939 Dowding wrote to his senior commanders:

In the training of Home Defence Fighters, it has hitherto been assumed that the fighter aircraft of any probable continental enemy will be unable to reach this country, and that therefore his bombing raids will be unescorted. The possibility cannot be excluded, however, that the enemy might over-run the Low Countries at a very early stage of the war and, using aerodromes or refuelling grounds in Holland and Belgium, might be able to send over fighter escorts with his bombing raids . . .

Messerschmitt 109s flying in the loose Schwarm tactical formation that was far superior to that used by Fighter Command.

In the light of what was to happen, this was a prophetic statement. Yet in the autumn of 1939 it made little impact.

In any case there were serious doubts as to whether high-speed dogfighting between modern fighters was possible. The Royal Air Force Manual of Air Tactics, 1938 edition, solemnly stated: ‘Manoeuvre at high speeds in air fighting is not now practicable, because the effect of gravity on the human body during rapid changes of direction at high speed causes a temporary loss of consciousness, deflection shooting becomes difficult and accuracy is hard to obtain.’ To launch escorted bomber attacks, the Germans would need to capture airfields in Holland or Belgium, both of which were neutral at the time. The possibility that France might be forced out of the war and occupied was beyond the bounds of serious discussion at this time, so it is hardly surprising that British tactics were tailored to meet the main, unescorted bomber, threat.

In the bomber formations in general use, the usual element was the ‘V’ of three aircraft. The optimum element to engage these was, therefore, a section of three fighters. Thus the formation recommended for an RAF fighter squadron of twelve aircraft comprised four ‘V’s, each ‘V’ consisting of a section of three aircraft. The squadron commander flew in the middle of the leading ‘V’ and the other three ‘V’s flew behind in line astern. The fighters flew in close formation with one wingspan, about 10 yards, between them. The use of such a tight formation had definite advantages for the penetration of cloud, an important factor to be considered in planning air operations over Britain.

Directed by radio from the ground, the squadron commander was to lead his formation into position on one flank of the enemy bomber formation. Once there he ordered his sections into echelon, and took his section in to attack. Each fighter pilot was to position himself behind an enemy bomber where in the words of the 1938 RAF Manual of Air Tactics: ‘. . . he stays until either he has exhausted his ammunition, the target aircraft has been shot down, or he himself has been shot down or his engine put out of action’. The other sections were to queue up behind and attack after the section in front had broken away. Since these actions were to be fought beyond the range of enemy fighters, the attackers could concentrate their entire attention on the enemy bomber formation.

The tactical formation and the type of attack outlined above were not the only ones used by the Royal Air Force, but they were representative of the rigidity of tactical thinking present in all of them. It must be stressed, however, that against unescorted bombers these tactics were appropriate.

TURRET FIGHTER, THE DEFIANT

A major area of uncertainty at the end of the 1930s concerned the effectiveness of the defensive crossfire from a formation of bombers. Would this be sufficient to beat off attacks by enemy fighters? As an insurance against this possibility, the RAF issued a specification for a two-seat fighter carrying its four-gun armament in a power-operated turret mounted amidships. The new fighter was named the Defiant; in December 1939 No. 264 Squadron became the first to receive it.

In view of what was to happen to the Defiant when the air war began in earnest, it is important to appreciate the role for which it was designed. The turret fighter was intended exclusively as a bomber destroyer. Against an enemy bomber formation, it was felt that even a few such fighters would provide a powerful addition to the defence. The turret fighter could formate below, to the side or even in front of its target and bring the latter under sustained fire. It could choose the best position for the gunner to ‘outflank’ any armour protection the bomber carried and at the same time remain outside the bomber’s return fire. The Defiant’s four .303-inch Brownings could traverse through 360 degrees and elevate from the horizontal almost to the vertical. The fact that the guns could not be depressed below 17 degrees up when aimed forwards, to prevent the unsynchronised weapons shooting holes in the propeller blades, was not considered to detract seriously from the tactical role envisaged for the fighter.

Defiant fighters of No. 264 Squadron, the first unit to receive the type. This aircraft, designed to operate against unescorted bomber formations, carried its armament of four .303-in machine-guns in a power-operated turret amidships. (IWM)

Like so much of the equipment in use in Fighter Command – radar, the ground control system to direct fighters into battle, even the monoplane fighter itself – the operational value of the turret fighter could not be proved or disproved until the air war over Britain itself hotted up. Meanwhile, No. 264 Squadron’s Defiants were declared operational early in 1940; and by that time a second squadron, No. 141, was re-equipping with the type.

The use of turret fighters to ‘outflank’ it was one way of defeating the armour protection fitted to a bomber. Another way round the problem, the ‘frontal approach’, was to fit fighters with a weapon considerably more powerful than the .303-inch Browning. The gun selected was the French Hispano 20-mm cannon, which had the best armour-penetration capability of any weapon of that calibre available at the time. During the closing months of 1939, a Spitfire and a Hurricane were flying, each fitted with a prototype installation for two cannon. If the operational trials proved successful, the Hispano gun was to go into large-scale production. We shall follow the progress of the cannon later in this account.

IMPROVEMENTS TO FIGHTER COMMAND’S ‘SYSTEM’

Throughout the final months of 1939 there was a steady improvement in Fighter Command’s control and reporting system. Considering the haste with which it had been erected, the system was working surprisingly well. There had been failures both in equipment and operation, as the ‘Battle of Barking Creek’ had demonstrated. But as personnel gained experience, the weaknesses in the system were eradicated. Yet the greatest flaw in the system remained beyond the ability of the operators to cure: the poor performance of the Chain Home radar in tracking aircraft at altitudes below about 5,000 feet.

Fortunately for Fighter Command the prototype of a radar partially able to conquer this problem already existed at the beginning of the war. The Coastal Defence radar, designed to observe movements of shipping, proved considerably better than the Chain Home system in observing the movements of low-flying aircraft. If the height of its scanner was 50 feet above sea level and the sea was calm, it could detect aircraft flying at 500 feet 18 miles away. Aircraft at 1,000 feet could be seen 22 miles away and aircraft at 2,000 feet could be seen 35 miles away. Aircraft flying at 10,000 feet could be observed at a range of 90 miles. The new radar received the designation Chain Home Low (CHL), and was ordered into production at the highest priority. The first CHL station became operational in November 1939, followed during the next four months by eight others along the east coast of England. The CHL radar worked on a much shorter wavelength than the CH type; and instead of the fixed wide beam of the latter, it employed a narrow rotating beam (as used by modern search radars). As a result, the plotting accuracy and powers of discrimination of the CHL were much better than those of the earlier set. The CHL could provide useful confirmatory and amplifying information on aircraft tracked by CH stations. Like those from the CH stations, plots from the CHL stations were passed direct to Fighter Command Headquarters by landline, where they were filtered and disseminated through the system.

During the early part of the war there existed a ‘gap’ in the radar cover below 5,000 feet, through which raiders could fly unseen. To plug part of this gap the Chain Home Low radar entered service at the end of 1939. Mounted on towers up to 185 feet high, or a lower gantry overlooking a cliff, this set could detect aircraft flying over the sea at 500 feet at ranges of up to 18 miles.

THE PROBLEM OF THE NIGHT RAIDER

We have observed that at the beginning of the war British fighter defences were virtually impotent against night raiders. Work was in progress to improve the position but it was far from reaching fruition. An obvious answer was to fit a lightweight radar set into a fighter, so its crew could find targets for themselves. However, this technical requirement proved easier to state than to meet. At the beginning of the war the prototype of an airborne radar was undergoing trials in a Blenheim, but its performance was so poor it was unsuitable for service use. The maximum range of the set was a little over a mile. Its minimum range, 330 yards, meant that at night an enemy aircraft being overtaken by the fighter disappeared off the radar screen some time before the fighter pilot was close enough to see it visually. (Radar minimum range: while the radar transmitter is radiating its high-powered pulse, the receiver has to be switched off to prevent its being damaged. Thus echo signals returning from short range while the receiver is switched off are not displayed on the radar screen, and the radar is ‘blind’ to them.) Clearly, the development of the radar-equipped night fighter had a long way to go before it was likely to cause problems for an enemy.

THE NEED FOR MORE FIGHTERS

Whatever the nature of the air fighting when the war eventually did hot up, one thing was clear to the British Air Staff: more fighter squadrons were needed. Air Chief Marshal Dowding was pressing for twelve more squadrons for Fighter Command, to make up for those sent to France and also to bring his force to the level judged to be necessary for the defence of Great Britain. Other fighter squadrons were required by Coastal Command for convoy protection work; others still were needed to support the British Expeditionary Force in France.