On the night of Aug. 17, 1943, a rocket engineer named Wernher von Braun walked back to his quarters on a quiet stretch of the German Baltic coast and looked up. A full moon hung over the secret research town of Peenemünde. Then the first flares blossomed in the sky, and von Braun realised, too late, that nearly 600 British bombers were about to fall on the birthplace of Hitler’s wonder weapons.

What followed was Operation Hydra, one of the most daring precision raids Bomber Command ever attempted: a moonlit strike, deep into Germany, aimed not just at buildings but at the scientists building the V-1 flying bomb and the V-2 ballistic missile.

A target worth 600 bombers

By 1943, British intelligence had pieced together what was happening at Peenemünde from photo-reconnaissance and agents: the Germans were developing rockets and flying bombs that could hit London from across the sea. It made the remote site a priority target, but a fiendishly difficult one. It lay some 600 miles from the nearest British airfield, and to bomb it accurately the crews would have to fly in bright moonlight at around 8,000 feet, far lower than the usual bomber altitude, and far more exposed.

The crews were not even told the truth. In their briefings, the target was described as a site developing radar that “promises to improve greatly the German night air defence organisation.” The real aim was blunter: destroy the research, and kill the people who made it possible.

The first Master Bomber

Operation Hydra introduced a tactic that would reshape Bomber Command. For the first time in a full-scale raid, a single “Master Bomber,” Group Captain John Searby of No. 83 Squadron, circled the target throughout the attack, calling in fresh markers and directing the main force onto the right aiming points. There were three: the scientists’ and workers’ living quarters, the rocket factory and the experimental station.

It did not all go to plan. Some of the earliest markers fell two miles off, onto the Trassenheide camp holding forced labourers, and the opening bombs killed at least 500 of them before Searby dragged the attack back onto the housing estate. There, among roughly 170 German dead, were Dr Walter Thiel, the chief engineer of the rocket motors, and Dr Erich Walther, who ran the rocket factory, exactly the kind of irreplaceable experts the raid was designed to eliminate.

The third wave paid the price

For the first two of the raid’s three waves, a handful of Mosquitoes flew a noisy diversion toward Berlin, and most of the German night fighters chased the decoy to the capital. By the time they realised the real target was Peenemünde, the third wave was already over it, and the hunters arrived in force.

It was also the night the Luftwaffe first used Schräge Musik, upward-firing cannon mounted in night fighters that let them slide unseen beneath a bomber and rake its belly. Of the 40 bombers lost, most fell in that final wave. In all, 215 airmen did not come home, a loss rate of 6.7 percent, judged a grim but acceptable price for the target.

Was it worth it?

Post-war historians broadly agree that Hydra delayed work at Peenemünde by around two months. That may sound modest, but once the V-1s and V-2s began raining on Britain in 1944 they killed on the order of a thousand people a month, so even a short delay almost certainly saved many lives. The raid also pushed the Germans to disperse V-2 production into the underground Mittelwerk, a move that would consign thousands of concentration-camp prisoners to a horrific fate building the rockets.

Peenemünde survived, and so did most of its scientists, von Braun among them. But for one moonlit night, Bomber Command reached across occupied Europe and struck the very laboratory of the rocket age.

Sources: Wikipedia (Operation Hydra), RAF Bomber Command War Diary, Air Gunner Bob Gill DFM, RAF Benevolent Fund.