The raid on the Philips works at Eindhoven

On Sunday 6 December 1942, shortly after half past twelve, British bombers swept in at rooftop height over Eindhoven in the occupied Netherlands. Within a quarter of an hour or so No. 2 Group of RAF Bomber Command – 93–94 Bostons, Venturas and Mosquitoes according to British returns – bombed two plants belonging to the Philips concern: the huge Strijp complex and the smaller works on the Emmasingel near the town centre. Codenamed Operation Oyster, it was the largest and most successful undertaking by the RAF’s day bombers at this stage of the war. Philips production was halted for many months, but at the cost of fourteen aircraft, several dozen airmen and the lives of some 140–150 of the town’s inhabitants. The Dutch remembered the day as the “St Nicholas raid”, because it fell on the day after the feast of Sinterklaas.

The target: valves for the Wehrmacht

Before the war Philips had been one of Europe’s leading electronics manufacturers and research centres, known for its valves (vacuum tubes), its radio sets and its work on infrared technology. Some members of the Philips family and of the board had left for the United States in May 1940 and directed the firm’s foreign subsidiaries from there, but the factories in Eindhoven, the town’s largest employer, worked under German supervision for the Reich. In April 1942 the British Air Ministry and the Ministry of Economic Warfare drew up a list of the most valuable targets in the occupied countries, and Eindhoven stood at the top of it. The British estimated that the Philips works supplied around a third of the radio valves used in German military equipment, and they feared that the firm was conducting research for the Germans into radar and electronic warfare.

Choosing how to attack was difficult. The works lay in the middle of a Dutch town, so a large night raid by heavy bombers of the kind that Bomber Command under Arthur Harris was sending over Germany by night – and in the autumn over Italy as well – would have killed thousands of residents. The raid had to be made by day and with precision. Eindhoven, however, lay some 110 kilometres inland, beyond the reach of fighter cover. The four-engined Lancasters were not to be sent through the German fighter zone in daylight, and the Mosquitoes, few in number at the time, could not have carried the bomb load needed for so large a target. The task therefore went to No. 2 Group, Bomber Command’s only day bomber group, made up of medium-bomber squadrons based in Norfolk. Until then its crews had attacked targets on the coast and in northern France in small formations, at medium altitude and with a fighter escort. This time every squadron was to fly at once, low over the ground all the way, to evade radar and take the defences by surprise.

Preparations

The plan was approved on 9 November 1942 and the order issued on 17 November. For several weeks the crews practised flying in large formations at very low level, which was particularly dangerous in the Venturas, slower and harder to handle. The early rehearsals went badly: aircraft of different types reached the target from different directions and at different times. It was therefore settled that the Bostons would strike first, the Mosquitoes two minutes after them and the Venturas, carrying incendiaries, last of all, so that the smoke of the fires would not hide the target from those ahead of them. Two squadrons of new American B-25 Mitchell bombers were withdrawn from the operation, their crews being judged too inexperienced. In the end, according to British figures, 36 Bostons from three squadrons took part, 48 Venturas from a British, an Australian and a New Zealand squadron, and 10 Mosquitoes. The raid was led by Wing Commander James Pelly-Fry of No. 88 Squadron. The briefing took place on 2 December, but the weather intervened over the following days; the airfields stayed closed and the crews waited in isolation.

Over Eindhoven

On 6 December the meteorologists at last judged the weather over the Netherlands suitable. In the morning, to distract the German defences, the US Eighth Air Force sent Liberators against the airfield at Abbeville and 66 Flying Fortresses against the railway workshops at Hellemmes near Lille – one of the targets over which, two months earlier, the Americans had put their doctrine of daylight bombing to the test. Between 11.15 and 11.30 a.m. the No. 2 Group bombers took off and, under radio silence and less than thirty metres above the water, headed out over the North Sea. They crossed the coast at the mouth of the Eastern Scheldt, catching the anti-aircraft batteries by surprise, and flew on across Brabant, over Bergen op Zoom and Turnhout, to the target.

The Bostons of Nos. 88 and 226 Squadrons attacked the Emmasingel works, and No. 107 Squadron Strijp. Some aircraft dropped their bombs from low level with delayed-action fuses, others after climbing to about 450 metres, in a shallow dive. The Mosquitoes went in behind them, and the Venturas came last, dropping phosphorus incendiaries and high-explosive bombs with delays of several tens of minutes intended to hamper firefighting. According to the British analysis, about 83 per cent of the aircraft dropped a total of some 60 tons of bombs on the target, with great accuracy and concentration. Reconnaissance photographs showed heavy damage to both complexes.

The price, however, was a level of loss that No. 2 Group could not often sustain. Fourteen aircraft failed to return – nine Venturas, four Bostons and one Mosquito – and with them 62 airmen: losses of around 16 per cent of the force dispatched, and nearly 20 per cent among the Venturas. More than half the aircraft that did return were damaged. German Fw 190 fighters shot down few; the aircraft were lost mainly to light flak and to collisions with birds, trees and buildings, all too easy at such low altitude, especially in the smoke over the target. The group needed ten days to rebuild its strength.

Casualties on the ground

Bombs that missed the works fell on the neighbouring districts. Among the areas destroyed were the streets around the Demer and Fellenoord in the town centre. According to Dutch studies, some 140–150 inhabitants of Eindhoven were killed, together with seven German soldiers, and many people were wounded. Some of the residents’ post-war accounts reveal mixed feelings: grief for the dead and the ruined town went hand in hand with satisfaction that the Allies had struck at factories working for the occupier.

For the Philips management the destruction came as a shock. Frits Philips, son of one of the company’s founders, who ran the firm in the Netherlands, had since 1940 been playing a game with the occupier: feigning cooperation to protect the factories and the workforce while at the same time holding back production for the Reich. After the raid his greatest fear was that the Germans would deport the skilled workers to the Reich. He cleared the rubble and presented the supervisors with optimistic reconstruction plans, but carried out the work without haste. According to British and Dutch studies, restoring full production took about six months, and on 30 March 1943 the RAF sent Mosquitoes over Eindhoven to delay it again. In the spring of 1943, after a wave of strikes in the occupied Netherlands, the Germans shot several workers on the factory premises and held Frits Philips for several months in the camp at Vught.

Place in the war

Operation Oyster was the high point of daylight raiding by British medium bombers in 1942 and one of No. 2 Group’s most celebrated actions of the entire war. It proved that a large formation could penetrate at low level by day, without fighter cover, to a target deep in an occupied country and destroy it with a precision that Bomber Command’s night raids could not then dream of. At the same time it showed how costly such a method was: losses of around one-sixth of the force ruled out frequent repetitions of such raids. Harris’s night offensive by heavy bombers therefore remained the principal instrument of Britain’s air war, while precision daylight bombing from high altitude became the preserve of the Americans. In June 1943 No. 2 Group was transferred from Bomber Command to the new tactical air force being prepared for the invasion of the Continent; the group’s Mosquitoes later carried out precision attacks on individual Gestapo buildings in occupied Europe. Eindhoven was liberated on 18 September 1944, in the first days of Operation Market Garden.