De Me 210 was meant to be a straightforward, better Bf 110: a modern twin-engine Zerstörer with a cleaner airframe, remote defensive guns and more speed. So confident was the Reich Air Ministry that it ordered the aircraft into series production off the drawing board, before flight testing had shown whether it was any good. It was not. Early machines revealed dangerous instability, a savage stall and a tendency to flick into spins, and the accident rate was alarming.

The consequences rippled through the whole programme. Production had to be suspended with large numbers of airframes built or half-built; enormous resources were written off; and the episode became a byword for mismanagement in German aircraft procurement, feeding the friction around Erhard Milch and reportedly damaging Willy Messerschmitt’s own standing within his company. It is remembered as one of the costliest development failures the Luftwaffe suffered.

What saved the concept was that the problems were fixable rather than fundamental. Wind-tunnel work and flight testing traced the worst handling to the aircraft’s short rear fuselage and wing behaviour; lengthening the fuselage and fitting automatic leading-edge slats transformed it. Re-engined with the DB 603, the rehabilitated design was renamed the Me 410 — partly on merit, partly to leave the Me 210’s reputation behind. Figures for exactly how many Me 210s were built, converted or scrapped vary between sources and should be treated as estimates.

One of the Me 410’s most distinctive features was inherited from the Me 210 and made to work properly: a pair of remotely-operated gun barbettes, one faired into each side of the fuselage behind the cockpit. Each barbette carried a single 13 mm MG 131 machine gun that could traverse to cover the rear hemisphere. Crucially, the second crewman did not sit directly behind the weapons — he aimed and fired them by remote control from a sighting station, tracking an attacker through a periscopic sight while the guns themselves swung to follow.

The idea was clever. It let one man defend both sides of the aircraft, kept the guns in low-drag fairings rather than bulky manned turrets, and gave the gunner a better all-round view than a traditional rear cockpit. Against the Me 410’s worst enemy — a fast fighter diving from behind — the barbettes gave crews at least a fighting chance where the Bf 110’s single hand-held rear gun had often left them helpless. The mechanism was complex and its effectiveness varied, but as an engineering answer to the Zerstörer’s chronic tail vulnerability it was genuinely ahead of its time.

By 1943 the Luftwaffe’s central problem over Germany was the USAAF heavy bomber: massed, armoured, densely armed formations of B-17s and B-24s arriving by day. The Me 410 was pressed into the Zerstörer role against them, and it was armed to kill. Standard machines already carried a heavy nose battery of 20 mm cannon; specialist versions added far heavier weapons still — multiple 20 mm or 30 mm cannon, underwing 21 cm rockets to break up formations, and on the Me 410A-1/U4 a single enormous 50 mm BK 5 cannon adapted from an anti-tank gun. A single well-aimed round from that weapon could destroy a four-engine bomber outright.

The catch was physics. Every rocket rack, cannon and armour plate added weight and drag, and a heavily-armed Me 410 was slow, sluggish and predictable — exactly the wrong thing to be once long-range escort fighters arrived. When P-47 Thunderbolts and especially P-51 Mustangs began escorting the bombers all the way to their targets in 1944, the bomber-destroyers were hunted down before they could reach the bombers at all. The same heavy armament that made the Hornisse lethal to bombers made it a death-trap against fighters. It was, in the end, a weapon that had arrived just after the moment it might have won.

The Me 410 was a product of the wartime German state economy, built to state contracts and never sold on any open market, so a firm flyaway unit price in modern terms does not exist in the public record. Contemporary figures were quoted in Reichsmark and are hard to convert meaningfully across eight decades of inflation, currency reform and a command economy. There is likewise no reliable cost-per-flight-hour figure, and there never can be a modern operating cost, because no Me 410 is airworthy. Any precise dollar price attached to a Me 410 today should be treated as an estimate, not a sourced fact.