The Palm Sunday massacre

Towards evening on 18 April 1943, Palm Sunday, American fighter pilots over the Gulf of Tunis near Cape Bon came upon a huge formation of German transport aircraft. Some 65 three-engined Junkers Ju 52s, escorted by a dozen or so fighters, were flying just above the waves towards Sicily. Within a quarter of an hour or so, dozens of them had fallen into the sea or, riddled with bullets, had barely made it to the Sicilian coast. The Germans called the day the Palmsonntagsmassaker – the Palm Sunday massacre. It was the most spectacular episode of the Allied Operation Flax, which in April 1943 cut the air bridge linking the Axis armies in Tunisia with Europe.

The often repeated version according to which the aircraft shot down were flying to Tunisia to evacuate cut-off German troops needs correcting. The Junkers were not flying to Africa but returning from it: earlier that day they had delivered fuel and ammunition to Tunisia, and they were shot down on their way back to Sicily. There were people on board, it is true – according to accounts, wounded men, Luftwaffe personnel and some soldiers being sent back to Europe – but this was no evacuation of the army. Adolf Hitler would not agree to abandoning Tunisia, and the air bridge served above all to supply troops who were to defend themselves there to the end.

A bridge over the Strait of Sicily

From November 1942, when the Germans and Italians won the race for Tunis, the Axis armies in Tunisia lived on supplies brought across the Strait of Sicily. The sea route was becoming ever more deadly: British warships and aircraft from Malta, whose siege the Axis had failed to break, together with Allied aircraft from Algeria, were sinking ships one after another. According to British calculations, two-thirds of the shipping losses between Cape Bon and Sicily were inflicted by aircraft. Air transport therefore took on an ever greater share of the burden.

From January 1943 it was directed by Generalmajor Ulrich Buchholz, who had under him two groups of transport wings – one based near Naples, the other at Trapani at the western tip of Sicily. The aircraft flew in large formations of 80 to 120 machines, low over the water to avoid detection, and usually reached Africa around midday. The Ju 52s brought in on average some 90 tonnes of supplies a day, and the huge six-engined Messerschmitt Me 323 Gigants, of which there were few, another 30 tonnes. Italian Savoia-Marchetti SM.82s joined the flights. Escort fighters were in short supply: there was usually one for every five transports.

After the end of the Stalingrad airlift, which had cost the Luftwaffe several hundred aircraft, including 266 Ju 52s, and of the subsequent supply of the Kuban bridgehead, the Germans were able to send more machines to the Mediterranean. According to figures cited in the literature, the number of Axis transport aircraft in the region rose from 185 around 10 March to more than 400 at the beginning of April. At the peak, more than a hundred transports a day landed in Tunisia – by some accounts as many as 150.

The Flax plan

The Allies knew much more about this traffic than the Germans supposed. By reading encrypted German signals (Ultra intelligence) and through radio interception, they knew the flight schedules, the bases and the take-off times. The plan to intercept the air bridge was drawn up in March by the staff of the Northwest African Strategic Air Force, commanded by Major General Jimmy Doolittle. The operation was codenamed Flax. It was overseen by Doolittle’s superiors: the Allied air commander-in-chief in the Mediterranean, Air Chief Marshal Arthur Tedder, and the commander of the Northwest African Air Forces, Lieutenant General Carl Spaatz.

The idea was simple, but carrying it out required precision. The flight across the strait was short, so the fighters had to be over the sea exactly when the air convoys were passing. Twin-engined Lockheed P-38 Lightnings were to patrol the Gulf of Tunis under cover of escorting B-25 medium bombers attacking shipping, while Spitfires lay in wait further north for any aircraft that slipped past the Americans. At the same time B-17 and B-24 heavy bombers were to strike the crowded airfields in Sicily, in Tunisia and around Naples, destroying transports on the ground. Because of bad weather the start of the operation was postponed from the last week of March to 5 April.

The first day gave a foretaste of what was to come. In the morning P-38s caught a formation of Ju 52s over Cape Bon and shot down a dozen or so of them; the Americans claimed almost twice as many. Bombers attacked airfields at Tunis and near Palermo. According to the British official history, the Germans and Italians lost 27 German and 3 Italian transport aircraft that day. On 10 and 11 April the Lightnings broke up further formations – Italian SM.82s and German Ju 52s – and on 11 April the Luftwaffe alone lost 18 Junkers. From 12 April most of the operation’s tasks were taken over by the tactical air forces, including American squadrons attached to the British Desert Air Force – the air arm of the Eighth Army, which after the Battle of Wadi Akarit had moved to captured airfields in eastern Tunisia, closer to the strait.

The Germans, not suspecting that their communications were being read, continued to fly by day. Night did offer greater safety, but it limited the number of trips, and the front needed every tonne of fuel.

The evening of 18 April

Sunday 18 April began disappointingly for the Allies: the morning and afternoon patrols over the strait found no convoy. Towards evening the commander of the American 57th Fighter Group, part of the US Ninth Air Force but fighting alongside the Desert Air Force, sent all his squadrons on the last patrol of the day, together with the 314th Squadron of the 324th Group, which was attached to him. Forty-seven Curtiss P-40 Warhawk fighters reached the Gulf of Tunis. High above them, at around 4,500 metres, top cover was provided by 12 Spitfires of the British No. 92 Squadron RAF.

Not far from Cape Bon the Americans spotted, low over the water at a height of about 300 metres, a large formation heading north-east towards Sicily. According to later findings it comprised some 65 Ju 52s, escorted by a dozen or so fighters – German Messerschmitt Bf 109s and Italian Macchis – as well as a few twin-engined Bf 110s. The escort was too weak, and the heavy, slow Junkers flying in tight formation just above the waves had nowhere to escape to. The Warhawks attacked from above, flying along the column and firing at one machine after another, while the Spitfires engaged the German fighters. According to accounts from both sides, soldiers on board the transports fired light machine guns through the cabin windows and doors.

The battle lasted only a quarter of an hour or so. Aircraft burned on the water, and others crash-landed on the beaches of Cape Bon. The Allies lost six P-40s and one Spitfire. The American pilots initially claimed as many as 146 victories. After verification, 58–59 Ju 52s, 14 fighters and several Bf 110s were credited – some 75 aircraft in all – and that figure found its way into many studies. Actual German losses, established later from Luftwaffe records, were smaller but still very heavy: 24 Ju 52s, nine Bf 109s and one Bf 110 were shot down, and 35 more Junkers, damaged and with dead and wounded on board, managed to reach Sicily and crash-landed on its coast. Of the formation that had taken off from Tunisia, only a few machines landed unscathed that evening. It is not known exactly how many men died aboard the aircraft that were shot down.

Overclaiming was the rule in the air forces of every side – in the chaos of combat several pilots would fire at the same aircraft, and machines that were smoking and heading away over the water were counted as destroyed. The scale of the defeat was nevertheless obvious to both sides. For the Luftwaffe 18 April was a black day; for the 57th Group it was one of the most celebrated successes of American fighter aviation in Africa.

Gigants over the strait

The massacre did not end the operation. On 19 April South African pilots of No. 7 Wing of the South African Air Force broke up a formation of Italian SM.82s, which caught fire so easily that the airmen concluded they were carrying fuel. On 22 April, Maundy Thursday, came the second great slaughter. Over the strait a formation of some 20–27 fully laden Me 323s – carrying mainly fuel, according to most sources – was intercepted, escorted by fighters of Jagdgeschwader 27. They were attacked by P-40s of South African, British and Australian squadrons, covered by Spitfires – according to some sources including aircraft of the Polish Fighting Team, known as “Skalski’s Circus”. According to German figures, 16 or 17 Gigants were shot down, together with several escort fighters and an Italian Macchi; the Allies lost several P-40s. The huge, slow machines, each capable of carrying around ten tonnes of cargo or more than a hundred soldiers, burned like torches.

After this disaster Reichsmarschall Hermann Göring, Commander-in-Chief of the Luftwaffe, banned further daylight transport flights to Tunisia. Field Marshal Albert Kesselring, German Commander-in-Chief South, objected, knowing that without supplies Colonel General Hans-Jürgen von Arnim’s armies could not hold out for long. Göring gave way only in part: the flights were resumed, but mainly by night and on a roundabout route via Sardinia. Instead of the roughly 250 flights a day before Operation Flax, only 60–70 flights a night were possible. Allied bombers went on destroying transports on the ground – in the operation’s last strike some 70 Liberators bombed the airfields around Bari in southern Italy. Operation Flax in the strict sense ended on 27 April.

The overall tally is hard to establish, because losses on the ground, in the air and in accidents are mixed together in the sources. According to figures cited in the literature, in the less than three weeks of the operation the Germans and Italians lost well over a hundred transport aircraft in air combat, and dozens more were destroyed or damaged on airfields. On top of that came the loss of crews – experienced transport pilots, who were in short supply after Stalingrad as it was.

The end of the air bridge

The Palm Sunday massacre and the destruction of the Gigants four days later sealed the fate of the air bridge to Tunisia. From then on the Axis armies received only part of what they needed. Stocks of fuel and ammunition dwindled, and von Arnim’s panzer divisions were losing their ability to manoeuvre just as the Allies were preparing the final offensive on Tunis. The Luftwaffe, deprived of airfields and supplies, began withdrawing its units from Africa; by the beginning of May almost all that remained there were Italian fighter squadrons and one German group. Airmen and mechanics, unwilling to risk a flight in a transport, squeezed into the fuselages and cockpits of fighters alongside the pilots. The last supply flights took place on 4 May. At sea the Royal Navy imposed a similar blockade in May in Operation Retribution, and on 13 May 1943 the last Axis units in Africa surrendered – some 250,000 German and Italian soldiers went into captivity.

Operation Flax showed what Allied air superiority combined with signals intelligence had become. Neither of the Luftwaffe’s two great air bridges of the winter and spring of 1943 – to Stalingrad and to Tunisia – saved the encircled armies, and together they destroyed a large part of the German transport force along with its best crews. In the view of most historians, German air transport never regained its former strength, which in the following years limited the Wehrmacht’s ability to supply encircled garrisons and to mount airborne operations. The air superiority won over the Strait of Sicily became in turn the starting point for the next stage of the war in the Mediterranean – the landings in Sicily, Operation Husky, carried out in July 1943.