But perhaps the most notorious rocket mail pioneer was a German inventor named Gerhard Zucker. He spent 1931–1933 touring his home country and showing off various rocket designs — while touting their suitability for mail delivery. At some demonstrations, he sold special envelopes that would supposedly be carried aboard his rocket flights, though there’s little evidence that any of these envelopes ever actually made it off the ground.

Zucker demonstrating his rocket to Nazi officials. Image credit: Astronautix.

Most of his rockets failed to take flight, too. In one demonstration in 1933 in a town called Cuxhaven on the North Sea coast, the missile only managed a distance of 49 feet before coming crashing to the ground. The following winter he demonstrated his rocket to Nazi government officials, but no collaboration took place. He later claimed that they wanted him to carry bombs on the rocket, and he refused to do so.

Instead, Zucker made his way to Britain, where in May 1934 he exhibited some of his envelopes at the London Air Post exhibition. There, he convinced a photographer and stamp dealer to help in a quest to interest the British government in his rocket, using the same strategies he’d tried in Germany.

In the early morning hours of June 6, 1934, he successfully launched a test rocket to a height of about 2,625 feet from a hilltop on the Sussex Downs carrying a number of letters. A reporter and photographer from London’s Daily Express were present, and the headlines the next day announced ‘The First British Rocket Mail,” as well as a claim from Zucker that he’d soon be able to send regular post between Dover and Calais.

Around this time, the General Post Office in Britain was looking for a method to send mail over water during rough weather, and took notice of Zucker’s test flights. He was invited to prove his technology in Scotland, with Post Office staff asking him to transport mail between Scarp Island and Hushinish Point on the Isle of Harris — a distance of about one mile.

On July 28, 1934, the group arrived at the launch site and assembled the rocket, loaded with 1,200 pre-sold and highly-profitable envelopes. Zucker lit the fuse, but instead of shooting up into the air, there was a flash of light, a muffled explosion, and a cloud of smoke. Zucker apologized profusely and blamed the failure on the type of explosive used.

Three days later, on July 31, he tried again, packing a second rocket with the surviving envelopes from the first flight. Unfortunately, a similar explosion lit up the beach, and this time burning envelopes scattered the ground. The Post Office staff looked on unimpressed as Zucker rushed about trying to recover as many as possible — knowing that the scorched remains would be highly desirable among collectors.

A third and final attempt in Hampshire in December 1934 was also unsuccessful. Zucker’s excuse that the failure of this rocket was due to a gust of wind failed to convince the Post Office, which was looking for a solution that would work in stormy weather. To add consequence to an already bruised ego, the rocketeer was judged to be a “threat to the income of the Post Office and the security of the country” and promptly deported.

Image credit: Astrocollection.

On arrival in Germany, the unlucky Zucker was met by the Gestapo, which immediately arrested him on suspicion of espionage or collaboration with Britain. He was threatened with incarceration or commitment to an asylum but managed to dodge both in exchange for a promise not to conduct any further rocket experiments.

After serving in the Luftwaffe during the Second World War, he moved across the border from East to West Germany and became a furniture dealer. He began experimenting again with rockets, until an accident occurred on May 7, 1964 at a demonstration in Braunlage in which three people were killed. In the wake of the tragedy, all non-military rocket launches in West Germany were banned.

Ironically, this ban directly resulted in the closure of a civilian spaceport in Cuxhaven, where Zucker had failed to launch a rocket three decades beforehand. At that demonstration, a local space enthusiast named Hugo Woerdemann had been so impressed by the technology Zucker was using that he began his own rocket experiments at a research center there — eventually touted as the “Cape Canaveral of Germany.” After the accident in Braunlage, however, the firing grounds in Cuxhaven were permanently closed; they are now a protected national park.

As for Zucker, he went back to furniture — but began trying to launch small mail rockets again in the 1970s, financed by the same old fraudulent envelope scheme. He died at home in 1985, though his exploits in Scotland — or some semblance of them — were turned into a 2004 film called The Rocket Post.

On balance, it’s hard to say whether Zucker’s contributions to rocket mail were positive or negative. His incompetence and fraudulent behavior had fatal effects for the technology in several countries, both metaphorically and literally. But his fondness for the spectacle of a launch inspired many more competent scientists down the path of rocketry, and similar envelope-selling schemes financed their experiments and yielded far better results.