After the rocket, the Tintin shark submarine is certainly one of Hergé's most iconic creations. It is a key object in The Adventures of Tintin. It allowed the reunion of the heroes with Professor Calculus.
Contrary to his habit, Hergé did not really take reference points in the real world to imagine the submarine. However, he indicated that he was inspired by Auguste Piccard and his bathyscaphe to create the character of Calculus. But in fact, he was inspired more by the inventor himself than by his invention, because from a visual and functional point of view, the bathyscaphe is very different from Professor Calculus' machine. What the two vehicles have in common, however, is that they were designed exclusively for civilian use, which was exceptional at the time. During the Second World War, even if some engineers had begun studies of single or two-seater submarines, no prototype was produced and the idea of a "pocket submarine" for civilian use was not considered.
The choice of the shark for the cover of the famous submarine is explained by the geographical position of our heroes. According to the coordinates provided by Sir François Haddock (which must be calculated in relation to the Paris Meridian and not the Greenwich Meridian, as Tintin reminds us), the island and the wreck of The Unicorn can be located in the north-east of the Dominican Republic. As we know, these waters are home to a wide variety of sharks. The Professor's submarine was therefore very useful in blending in with the local marine fauna.