Fredrik Henrik Af Chapman - Navy Expansion

Navy Expansion

In 1776, Chapman became a civilian member of the Board of the Admiralty. His influence on the board and favor with the king resulted in critical reports of the current habit of the high seas navy to keep old ships afloat at great expense rather than spending more resources on building new, improved ships. Chapman's recommendations for improvements of the Karlskrona facilities was also received positively and approved by the king. The same year he was elected into the Royal Swedish Academy of Sciences as member number 175.

An expansion of the navy was seen as necessary, but the design of the new ships was still a matter of debate in the late 1770s. The old school of shipwrights, most prominently supported by the Sheldon family and senior navy officers like Admiral Carl Tersmeden in Karlskrona, favored the old design with only minimal alterations based on the older methods of empirically-grounded ship design. The new school, based in Stockholm and Sveaborg had in Chapman its most capable representative and was supported by General Admiral Henrik af Trolle and the court, pushed for more radical changes and designs based on the theoretical designs and experimental physics and mathematics. Chapman's first proposal for a new standard for ships of the line was the Wasa, completed in 1778. Its superstructures were lowered considerably by removing the poop deck almost entirely to add stiffness and the gun decks were placed higher than in older designs to allow them to be used even in rough weather, when the ship rolled.

The Wasa went through sea trials in 1779 where it was compared with Sofia Magdalena, a ship of the older design which was favored by the conservative factions within the establishment. The Wasa to some degree outperformed Sofia Magdalena, but never completely outclassed it. The opposition took advantage while Chapman was convinced he needed to make only minimal adjustments to his design to produce a vastly superior warship. The portrayal of the conflict as conservative reactionaries versus progressive pioneers is shared by several historical authors, including Daniel G. Harris, Chapman's modern biographer. This includes descriptions of action approaching sabotage in providing substandard rigging material for the Wasa and outright insubordination on the part of Gilbert Sheldon by making the hull 60 cm (2 ft) shorter than planned. Swedish Jan Glete has argued this description is partial to Chapman and his supporters and stressed the political nature of the conflict; Chapman and af Trolle were both close to the royal circles and their aims coincided with those of king Gustav III, who wished to assert control of the armed forces and to portray himself as an enlightened monarch who encouraged innovation against the conservative navy establishment in Karlskrona.

Chapman also worked out several improvements of the royal shipyards that he supervised, including recommendations for the use of sheds to protect ships from deterioration when they were in reserve, something that was particularly important for the often lightly built galleys. Showing considerable organization skills, he made detailed plans on how to make naval vessels ready for quick mobilization and proposed a more efficient system of management for shipyards based on his experiences in Sweden and abroad.

Requested by king Gustav III to comment on Patrik Miller's warship Experiment (which Miller had sent to the king) he called it the "English (sic) sea-spook". The king sent Chapman a snuff box filled with rutabaga seeds. The snuff box, illustrated with marine motifs, including Experiment, is now in the collection of the Victoria & Albert Museum in London.

At the age of 60, he was appointed head of the naval shipyard at the main naval base of Karlskrona. Here, he built new ships and organized production series for ships based on prefabrication methods, which meant that he could deliver twenty new ships in just three years, ten ships-of-the-line and ten frigates. Chapman also became a pioneer in the application of mathematical calculations in the relation between rigging, displacement, water resistance, the center of gravity of hulls, stability and tonnage.

In order to test his mathematical theories, he had a 100 m long pool constructed outside Karlskrona, where he tested various hull designs with scale models. The models were pulled through the water with pulleys and ropes. This method gave realistic values and is similar to the method used today to establish the hydrodynamic features of new hull designs.