Heavy raid on Portsmouth. Convoy in Thames Estuary, radar stations and coastal airfields attacked.

Night: Widespread harassing raids.

Weather: Fine with some mist patches.

Enemy Action by Day

On the eve of Adler Tag (Eagle Day), the Luftwaffe launched a powerful and highly coordinated assault across southern England in what amounted to a full-dress rehearsal for the long-anticipated aerial offensive. Though Göring had designated 13 August as the formal start of the assault on Britain’s air defences, operations on the 12th marked a dramatic escalation. Radar installations, Channel convoys, and airfields were all targeted in a sequence of concentrated strikes designed to blind and destabilise Fighter Command’s front-line response.

07:20–10:00 Hours: Lympne and Attacks on the Radar Chain

At 07:20 hours, radar stations along Britain’s south-east coast picked up German aircraft approaching across the Channel. Fifteen Do 17s of I./KG 2, escorted by Bf 109s of JG 54, were heading towards RAF Lympne, while Erprobungsgruppe 210—equipped with Bf 110 and Bf 109 fighter-bombers under Hauptmann Walter Rubensdörffer—prepared to strike the Chain Home radar network.

Spitfires of Nos. 54 and 610 Squadrons were scrambled to intercept. The German fighter escort engaged the RAF over the Kent coast while the Dorniers pressed on towards Lympne, sweeping across the airfield at approximately 08:00 hours. Within seconds, 141 bombs fell across the station, cratering the landing ground and damaging a hangar and several offices, although no casualties were reported.

During the fighting, Flying Officer H.K.F. Matthews of No. 54 Squadron shot down a Bf 109E-1 of 1./JG 26, which exploded near Elham, killing its pilot, Oberleutnant Friedrich Butterweck.

Shortly after 09:30 hours, the four sections of Erprobungsgruppe 210 began their attacks on the Chain Home stations at Rye, Pevensey, Dover and Dunkirk. Oberleutnant Wilhelm Rössiger’s section struck Rye, damaging the accommodation block and temporarily putting the radar station out of action. At Pevensey, Oberleutnant Martin Lutz’s section caused more serious disruption when a 500 kg bomb severed the main power cable, knocking out the station and leaving it without power for several hours. Oberleutnant Otto Hinze’s section attacked Dover, damaging several outbuildings and electrical equipment, although the main transmission towers remained operational. Rubensdörffer himself led the attack on the Dunkirk station near Canterbury, but morning haze and navigational errors limited the damage.

The raids succeeded in disabling three radar stations for several hours, significantly hampering Fighter Command’s coverage along the south-east coast. Although Ventnor on the Isle of Wight remained unaffected during this phase, the temporary disruption of coastal radar left a critical gap in the RAF’s early warning screen. Crucially, the Luftwaffe misjudged the outcome—believing the radar sites had been destroyed and that Britain’s defensive network was permanently compromised.

11:00 Hours: Dive-Bombing of Convoys Arena and Agent

Shortly before midday, IV./Lehrgeschwader 1 launched a concentrated dive-bombing assault against two British convoys moving through the Thames Estuary—codenamed Arena and Agent. Led by Hauptmann Erwin Röder, the Ju 87 Stukas swept in low from altitude, their Jericho-Trompete sirens wailing as they plunged towards their targets. Providing top cover were Bf 109s of III./Jagdgeschwader 26.

The RAF mounted a rapid response. Hurricanes from Nos. 151 and 501 Squadrons, together with Spitfires from No. 65 Squadron, intercepted the raiders as they descended through the coastal cloud base. The dogfights that followed over the estuary were chaotic and intense, with aircraft weaving through anti-aircraft bursts and smoke rising from damaged ships below. In the confusion, the RAF lost four fighters, with two pilots killed. Among them was Pilot Officer Robert Beley of No. 151 Squadron, shot down in Hurricane P3304 during combat with Bf 109s. Though badly injured, he baled out and was rescued from the sea, but died later that day at RAF Manston. Flying Officer Kazimierz Lukaszewicz of No. 501 Squadron also failed to return in Hurricane P3803 following combat with enemy fighters west of Ramsgate.

One Ju 87 was confirmed shot down, but the German formation succeeded in completing its bombing run, inflicting heavy damage. The Royal Navy minesweeping trawlers HMT Pyrope and HMT Tamarisk were sunk off the North East Spit Buoy in the Thames Estuary. Six ratings were killed aboard Pyrope and seven aboard Tamarisk. Eyewitnesses along the coast later described scenes of devastation—burning hulls drifting in the estuary, lifeboats scattered across the water, and thick columns of smoke rising from the Channel.

11:51–12:45 Hours: Strike on Ventnor and the Portsmouth Raid

At 11:51 hours, radar stations along the south coast detected a massive Luftwaffe raid assembling over Cherbourg. The formation comprised 63 Junkers Ju 88 bombers from KG 51, escorted by over 120 Messerschmitt Bf 110s of ZG 2 and ZG 76, with additional high cover provided by Bf 109s of JG 53. It was one of the largest coordinated attacks of the campaign to date.

As the bombers crossed the southern coastline, a splinter formation of fifteen Ju 88s broke away. This group, led by the unit’s Kommodore, Oberst Johann-Volkmar Fisser, was tasked with neutralising the Chain Home radar installation at Ventnor on the Isle of Wight. In a precisely executed strike, Fisser’s aircraft released four 250 kg bombs directly onto the radar site. The bombing struck the station hard, damaging its buildings and essential services and starting intense fires across the site.

Ventnor was put out of action for three days. In the meantime, an obsolete mobile radar set was erected on the site to provide limited emergency coverage, helping to conceal the full extent of the damage from German signals intelligence.

The raiders were met by Spitfires from Nos. 152 and 609 Squadrons. No. 152 Squadron attacked the Ju 88s while No. 609 Squadron became heavily engaged with their fighter escort.

During the attack, the Ju 88A (9K+AA) carrying Fisser was shot down at approximately 12:25 hours by a combination of ground defences and fighters of No. 152 Squadron—Pilot Officers W. Beaumont and R. M. Hogg, Flight Lieutenant F. M. Thomas, and Sergeant E. E. Shepperd—and crashed at Godshill Park. He was killed, while Leutnant F. Schad, Oberleutnant W. Lüderitz, and Sonderführer A. Nothelfer were captured, the latter badly burned. His loss was a significant blow to KG 51, which would later name a Staffel in his honour.

Meanwhile, the main force continued eastward and launched a major bombing attack on Portsmouth. Home to the Royal Navy’s largest dockyard, the city bore the brunt of the assault. Despite fierce resistance from naval and army anti-aircraft batteries, dozens of high-explosive and incendiary bombs struck the dockyard, industrial works and surrounding residential districts.

Fires broke out across Portsmouth and Gosport, causing substantial damage and casualties as the bombing spread beyond the naval installations into the surrounding urban areas.

Hurricanes of Nos. 145, 213 and 257 Squadrons, together with Spitfires of Nos. 152, 266 and 609 Squadrons, intercepted the raiders over Portsmouth, Spithead and the Isle of Wight. The fighting spread across the Solent and south of the island as RAF fighters attacked the bombers and tangled with their escorts.

No. 145 Squadron suffered particularly heavily. Pilot Officer John Harrison, Sergeant Josef Kwiecinski and Flight Lieutenant Wilhelm Pankratz all failed to return; before they were killed, the three pilots had shared in the destruction of a Bf 110. No. 152 Squadron lost Flight Lieutenant Latham Withall and Pilot Officer Douglas Shepley, while Nos. 213 and 257 Squadrons suffered further losses.

Pilot Officer W.S. Williams of No. 266 Squadron (RNZAF) distinguished himself by shooting down a Ju 88 before being forced to land at Bembridge after enemy fire damaged the oil system of his Spitfire N3175 south of Portsmouth. He escaped moments before his Spitfire exploded in flames.

KG 51 and its fighter escort were hit hard in return. At approximately 12:10 hours, a Ju 88A-1 (9K+FS, W.Nr. 5072) of 8./KG 51 was shot down while bombing Portsmouth Docks. Oberleutnant E. Wildermuth, Oberleutnant O. Stark and Unteroffizier H. Droese were captured, while Unteroffizier K. Rosch was reported missing and believed killed.

A Ju 88A-1 (9K+EL, W.Nr. 3134) of 3./KG 51 was destroyed shortly afterwards, exploding over Thorney Island at approximately 12:15 hours, with the wreckage falling near Westbourne; Oberleutnant H. Graf, Oberfeldwebel H.-G. Czepik, and Unteroffizier W. Floeter were killed, while Gefreiter G. Fleischmann baled out and was captured.

At approximately 13:00 hours, another Ju 88A-1 (9K+CL) of the same unit was shot down and crashed near Godstone; Unteroffizier K. Zimmermann and Obergefreiters K.-H. Fahrenheim and O. Hansmann were captured, while Gefreiter T. Dickel was killed.

Among the German fighter escorts lost was a Bf 110D-0 (3M+MK, W.Nr. 3316) of 2./ZG 2, which was shot down over Portsmouth Harbour and crashed into the Channel. Hauptmann H.-P. Kulbel and Unteroffizier F. Budig were both killed; Kulbel’s body later washed ashore at Wimereux, near Boulogne, while Budig’s was recovered and buried at St Ann’s Hill Cemetery, Gosport.

One of the day’s most significant Luftwaffe losses occurred at approximately 12:35 hours, when Hauptmann Harro Harder, Gruppenkommandeur of III./JG 53, was shot down over the Isle of Wight. Likely brought down by Spitfires of No. 609 Squadron, Harder’s aircraft crashed into the Channel, and his body was later recovered near Dieppe. A respected ace and aggressive leader, Harder had claimed five Spitfires in just 48 hours the previous week.

12:50–17:30 Hours: Luftwaffe Strikes on RAF Airfields

The next phase of the Luftwaffe’s offensive shifted to RAF airfields across south-east England, as German commanders sought to destroy Fighter Command’s forward operating bases.

At 12:50 hours, Erprobungsgruppe 210—flying Bf 110s and bomb-laden Bf 109s—launched a precision assault on RAF Manston. No. 65 Squadron was in the midst of scrambling when the first bombs struck. Most aircraft managed to take off, but Pilot Officer Kenneth Hart was only about thirty feet above the ground in Spitfire R6712 when a small bomb exploded beneath him. The shock apparently stopped the engine, but Hart managed to land safely. The Spitfire itself was undamaged and flew again later that afternoon.

The raid on Manston was brief but devastating. In the space of five minutes, over 150 high-explosive bombs tore through the airfield, gouging more than 100 craters into the chalk subsoil and damaging two hangars. The station workshops were obliterated in a direct hit, killing a civilian clerk. The scale of the bombardment sent immense plumes of white chalk dust billowing skywards—so thick that aerial observers mistakenly believed the airfield was engulfed in flames.

Moments later, a follow-up wave arrived: Dornier Do 17s of I./KG 2, escorted by Bf 109s from JG 54, swept over the battered field to intensify the destruction.

Two Blenheim fighters of No. 600 Squadron were also damaged on the ground. Despite the damage inflicted at Manston, ground crews worked through the night, and the airfield was operational again within 24 hours.

Later in the afternoon, at 17:30 hours, RAF Hawkinge became the next target. Do 17s of KG 2 and KG 76, accompanied by Bf 110s of Erprobungsgruppe 210, came in over Folkestone and struck the station before its defences could fully react. A direct hit destroyed No. 3 hangar; No. 5 hangar sustained serious damage; fires broke out in the main stores building and clothing depot. Two married quarters were flattened. Bomb damage assessment identified 28 craters across the site, some plunging as deep as 28 ft.

Five men were killed—three RAF airmen and two civilian contractors—and six airmen were seriously injured. Two Spitfires under repair were seriously damaged, while one or two others were struck by splinters. The raid caught the ground defences largely by surprise, with only two Hispano cannons managing to return fire. Nevertheless, Hawkinge remained partially operational and emergency repairs began before nightfall.

Shortly thereafter, RAF Lympne was attacked for the second time that day. Around 242 bombs fell across the aerodrome in two runs, destroying six of the original hangars and badly damaging domestic accommodation. Delayed-action bombs hampered repair work and the landing ground was rendered unserviceable. Leading Aircraftman Sidney Herbert Bell was killed, while Corporal J. Anderson and Aircraftman 2nd Class Charles Clarkson were seriously wounded; Anderson later died from his injuries. Hurricanes of No. 501 Squadron engaged the raiders and their fighter escort as the German formations withdrew towards the coast.

At about the same time, Hurricanes of No. 56 Squadron intercepted a formation of Do 17s north of Margate. During the engagement, Pilot Officer Geoffrey Page, flying Hurricane P2970, closed on the bombers and was hit by return fire—his fuel tank ignited, and flames engulfed the cockpit. Though severely burned, he unfastened his harness, forced open the canopy, and bailed out into the Channel. He was rescued by two men in a motor boat from a small coaster and subsequently transferred to the Margate lifeboat. Page’s injuries were grievous—his face and hands extensively burned—but he would survive, endure months of reconstructive surgery, and ultimately return to combat, becoming one of Fighter Command’s most determined and inspiring figures.

Fighter Sweeps and Evening Losses

The fighting over Kent and the Channel continued throughout the afternoon as RAF and Luftwaffe fighter units clashed in a series of scattered engagements. German fighter formations operating over the coast suffered further losses, while later sweeps sought to draw Fighter Command into combat.

At approximately 12:30 hours, a Bf 109E-4 of 2./JG 26 was shot down into the sea near Folkestone; Oberleutnant H.W. Regnauer survived and was captured.

Elsewhere, II./JG 52—newly transferred to the Channel front—suffered losses including a Bf 109E-1 (Werknummer 3367) of 2./JG 52, shot down at approximately 12:45 hours by Pilot Officer J. A. P. McClintock of No. 615 Squadron during combat over Hastings; the aircraft force-landed near Berwick, and Unteroffizier Leo Zaunbrecher was captured.

Later in the afternoon, III./JG 26 launched a free-hunting (Freie Jagd) patrol over the Dover area, seeking to draw out RAF fighters. While few responded, three Spitfires were claimed by Luftwaffe pilots—Leutnant Heinz Ebeling, Feldwebel Gerhard Gryzmalla, and Leutnant Johannes Naumann—in combat near Manston.

At approximately 18:00 hours, a Bf 109E-4 of III./JG 54 was shot down by Flying Officer H. J. Woodward of No. 64 Squadron over Dover and force-landed near Margate; Oberleutnant A. Dresze was captured.

Reconnaissance Operations

Reconnaissance missions ranged deep across Britain throughout the day. One enemy aircraft was tracked flying inland from Shoreham as far as Northolt, while another conducted a wide sweep over South Wales and Somerset. Most notably, a Ju 88—likely from Fernaufklärungsgruppe 123—ventured more than 250 miles into the Atlantic before turning south along the Irish coastline, underscoring the Luftwaffe’s growing operational reach and the expanding scope of its strategic reconnaissance efforts.

Enemy Action by Night

After nightfall, the Luftwaffe resumed operations under cover of darkness. RAF Sealand in Cheshire was bombed by II./KG 27, marking the beginning of an increasingly coordinated night offensive against British airfields. One He 111H-3 (1G+AC) of II./KG 27 was shot down at approximately 02:00 hours while attacking Bristol Docks, likely by a combination of night fighter interception and anti-aircraft fire; the aircraft crashed at Sturminster Marshall near Wimborne. Major F.-K. Schlichting, Oberfeldwebels G. Lohning, H. Frey, and W. Bendrich, together with Major H.-J. Brehmer, all baled out and were captured. Meanwhile, a Heinkel He 111 of 9./KG 55, returning from a raid on Bristol, crashed near Rambervillers in France, resulting in the deaths of two crew members.

Elsewhere, sporadic bombing raids took place near Nottingham, Norwich, Blackpool, and Bircham Newton, though little damage was reported. Minelaying operations also continued in earnest, with activity noted off the Thames Estuary, the Bristol Channel, and along sections of the East Coast.

Summary

Monday, 12 August 1940 marked a pivotal escalation in the Luftwaffe’s campaign against Britain. In a tightly coordinated assault, German air fleets struck with unprecedented intensity—targeting Chain Home radar stations, coastal convoys, RAF airfields, and civilian infrastructure. The radar site at Ventnor was knocked out; airfields at Manston, Hawkinge, and Lympne were badly damaged; and Portsmouth endured a major daylight raid, with its dockyard, harbour, industrial premises and surrounding districts attacked.

Convinced these blows had crippled Britain’s defensive system, the Luftwaffe believed Fighter Command was nearing collapse.

They were mistaken.

Repair crews worked swiftly. The morning attacks had failed to break the Chain Home network, while Ventnor—the most seriously damaged station—remained out of action for three days. Hawkinge remained usable, Manston was rapidly restored, and work began immediately on the badly damaged airfield at Lympne. Across Britain, 54 people were killed and 159 injured during the day’s attacks, approximately two-thirds of them civilians. Though Fighter Command lost 18 aircraft and 11 airmen, its core strength held. The system bent under pressure—but it did not break.

German Losses:
Airmen: 52 | Aircraft: 32

British Losses:
Airmen: 11 | Aircraft: 18

Hurricane P3304, No. 151 Squadron. Aircraft destroyed.
P/O R.W.G. Beley. Died of wounds. Shot down by Bf 109. Crashed into sea and rescued. Taken to Manston.
http://www.bbm.org.uk/airmen/Beley.htm

Spitfire K9999, No. 152 Squadron. Aircraft lost.
P/O D.C. Shepley. Missing in action. Last seen in combat with Ju 88. Failed to return to base.
http://www.bbm.org.uk/airmen/Shepley.htm

Spitfire P9456, No. 152 Squadron. Aircraft destroyed.
F/L L.C. Withall. Missing in action. Shot down by gunfire from Ju 88, believed crashed into sea.
http://www.bbm.org.uk/airmen/Withall.htm

Hurricane R4180, No. 145 Squadron. Aircraft destroyed.
P/O J.H. Harrison. Missing in action. Shot down over Channel during combat with Ju 88s and Bf 110s.
http://www.bbm.org.uk/airmen/HarrisonJH.htm

Hurricane P3391, No. 145 Squadron. Aircraft lost.
Sgt J Kwiecinski. Missing in action. Failed to return to base.
http://www.bbm.org.uk/airmen/Kwiecinski.htm

Hurricane R4176, No. 145 Squadron. Aircraft destroyed.
F/L W. Pankratz. Missing in action. Shot down over Channel during combat with enemy aircraft.
http://www.bbm.org.uk/airmen/Pankratz.htm

Spitfire P9333, No. 266 Squadron. Aircraft destroyed.
P/O D.G. Ashton killed. Aircraft burst into flames from gunfire from enemy aircraft.
http://www.bbm.org.uk/airmen/AshtonDG.htm

Hurricane P2802, No. 213 Squadron. Aircraft destroyed.
Sgt S.G. Stuckey. Missing in action. Shot down over Channel by Bf 109s.
http://www.bbm.org.uk/airmen/Stuckey.htm

Hurricane P2854, No. 213 Squadron. Aircraft lost.
Sgt G.N. Wilkes. Missing in action. Last seen in combat with Bf 109s. Failed to return to base.
http://www.bbm.org.uk/airmen/Wilkes.htm

Hurricane P3662, No. 257 Squadron. Aircraft lost.
P/O J.A.G. Chomley. Missing after a combat with enemy aircraft off Portsmouth.
https://www.bbm.org.uk/airmen/Chomley.htm

Hurricane P3803, No. 501 Squadron. Aircraft lost.
F/O K. Lukaszewicz. Missing in action following combat with enemy fighters west of Ramsgate.
https://www.bbm.org.uk/airmen/Lukaszewicz.htm

Photo Descriptions

1. A view of Portsmouth Harbour (looking to the Portsmouth side) during an air raid of 12th August 1940. © IWM (MH 156)
2. Another view of Portsmouth Harbour (looking to the Portsmouth side) during an air raid of 12th August 1940. © IWM (MH 155)
3. Ventnor RDF station on the Isle of Wight under attack by Ju 88 bombers of Kampfgeschwader 51, 12 August 1940.
4. Bomb-damaged houses on the corner of Spring Garden Lane and Grove Avenue in Gosport, Hampshire, after a raid on 12 August 1940. The vicarage on the corner itself was completely destroyed. © IWM (MH 149)
5. Messerschmitt Bf 109E of 2./JG 52 resting in a wheat field after being shot down during a combat over Hastings, 12 August 1940. Its pilot, Unteroffizier Leo Zaunbrecher, was captured. © IWM (HU 104719)
6. Army officers inspect the wreckage of Messerschmitt Bf 109E-1 (W.Nr. 3367) “Red 14” of 2./JG 52, which crash-landed in a wheatfield at Mays Farm, Selmeston, near Lewes in Sussex, 12 August 1940. © IWM (HU 73928)
7. Locals watch as troops and police inspect Messerschmitt Bf 109E-1 (W.Nr. 3367) “Red 14” of 2./JG 52, which crash-landed in a wheatfield at Mays Farm, Selmeston, near Lewes in Sussex, 12 August 1940. © IWM (HU 50153)
8. No. 3 hangar at RAF Hawkinge following the attack by Erprobungsgruppe 210 on 12 August 1940.
9. Hawker Hurricane Mark Is of No 32 Squadron coming in to land for refuelling and rearming at Biggin Hill, watched by an airman standing with a signalling flag in the foreground, August 1940. © IWM (HU 54519)