Messerschmitt Bf 110

In the mid-1930s air forces everywhere were seduced by the idea of the strategic heavy fighter — a big, long-range, heavily armed twin-engined machine that could clear a path for the bombers, break up enemy formations, and range far beyond the reach of short-legged single-seaters. The Luftwaffe called it the Zerstörer (“destroyer”), and made it a priority project. Willy Messerschmitt’s answer, the Bf 110, first flew on 12 May 1936.

It became the prestige aircraft of the Luftwaffe. Hermann Göring lavished attention on the Zerstörergeschwader, staffing them with hand-picked crews and calling them his elite — his “Iron Ones”. On paper the concept was compelling; in practice its central assumption, that a heavy twin could hold its own against nimble single-seat fighters, had never been truly tested. In 1940 it would be.

The Bf 110 was built around two Daimler-Benz DB 601 inverted-V12s — the same engine family as the Bf 109 — giving the C-series about 1,100 hp a side and a top speed near 560 km/h, genuinely fast for 1940. Its great asset was range: it could escort bombers to targets the Bf 109 could never reach, and loiter there.

Its punch was concentrated and forward-firing: a nose battery of two 20 mm MG FF cannon and four 7.92 mm MG 17 machine guns that could saw a bomber apart in a single pass. Behind the pilot sat a radio-operator/gunner with a single hand-aimed 7.92 mm MG 15 covering the tail — a weak defence that hinted at the aircraft’s fatal flaw. For all its speed and firepower, the Bf 110 was heavy, and it could not turn with a modern single-seat fighter.

At first the Zerstörer looked unstoppable. Over Poland in 1939, in the Norwegian campaign, and across the Low Countries and France in the spring of 1940, the Bf 110 ranged far and hit hard against opposition that was scattered, outnumbered or obsolete. Its speed let it choose when to fight, and its firepower made those fights short.

The Zerstörer units built a swagger to match Göring’s billing. But every one of those victories had been won in conditions that flattered the type — against enemies without the numbers, the radar or the fighters to make it pay for its lack of agility. That reckoning was waiting across the Channel.

In the Battle of Britain the Zerstörer myth collapsed in a matter of weeks. Sent to escort the bomber streams, the Bf 110 met Spitfires and Hurricanes flown by pilots who quickly learned that the heavy Messerschmitt could not out-turn them. Time and again the Bf 110s were forced onto the defensive, some famously forming defensive circles — each aircraft guarding the tail of the one ahead — the posture of a hunter turned prey.

The humiliation was total: the destroyers took such losses that they increasingly needed the single-engined Bf 109s to escort them. The escort now needed an escort. By the end of the summer the Zerstörer had been quietly pulled back from daylight over England, its reputation in ruins and its role as a day fighter finished.

And then the Bf 110 found the war it had been waiting for. As RAF Bomber Command turned to the night skies, the Luftwaffe needed a stable, roomy, heavily armed platform that could carry a radar operator and his equipment — and the Bf 110 was exactly that. It became the backbone of the Nachtjagd, the German night-fighter force. Fitted with Lichtenstein radar and, later, upward-firing “Schräge Musik” cannon that let it slide unseen beneath a bomber and rip open its belly, the Bf 110 G-4 was the deadliest night fighter of the war.

The scores were staggering. Major Heinz-Wolfgang Schnaufer, the “Night Ghost of St. Trond”, ran up 121 night victories in the Bf 110 — the highest-scoring night-fighter ace in history. By day the type had a harder time: heavy-cannon and rocket-armed Bf 110s were effective bomber destroyers against the USAAF’s daylight formations in 1943, until the arrival of the P-51 Mustang made hunting bombers a death sentence. Because its intended successor, the Me 210, was a failure, the “obsolete” Bf 110 stayed in production and in the front line to the very end.

The Bf 110 is the great cautionary tale of the heavy-fighter idea. Everything the Zerstörer concept promised — speed, range, crushing firepower — the Bf 110 delivered; the one thing it could not do was survive against nimble single-seat fighters in daylight, and that one failure undid the whole theory over southern England in 1940.

Yet few aircraft have been so thoroughly redeemed by a second career. Judged as Göring’s day-fighting elite it was a costly illusion; judged as the instrument of the night war it was one of the most successful and lethal aircraft the Luftwaffe ever flew. Roughly 6,000 were built, and the type that was humbled in the Battle of Britain went on to kill more RAF aircrew, in the dark, than almost any other.

• William Green, Warplanes of the Third Reich (Macdonald & Co.).
• J. R. Smith & Antony L. Kay, German Aircraft of the Second World War (Putnam).
• John Weal, Messerschmitt Bf 110 Zerstörer Aces of World War 2 (Osprey, Aircraft of the Aces).