Metal-cased rocket artillery

Metal-cased rocket artillery emerged in the mid-seventeenth century from the recognition that iron tubes could contain propellant more safely and effectively than paper, pasteboard, or wood casings. The transition from combustible to metallic rocket construction represented a crucial step in rocket development, though the technology would not achieve military dominance until Mysorean forces deployed it against the British two centuries later.

The adjacent possible for metal-cased rockets built upon centuries of rocket development. Chinese fireworks and military rockets had used paper casings since at least the thirteenth century. European artillery treatises described rockets in increasing detail through the fifteenth and sixteenth centuries. Kazimierz Siemienowicz's 1650 "Artis Magnae Artilleriae pars prima" provided comprehensive rocket designs, though his rockets still used paper, pasteboard, and wood casings, sometimes reinforced with iron wire.

The conceptual leap to metal casings offered several advantages. Metal could withstand higher internal pressures, permitting more powerful propellant charges. Metal resisted moisture that could destroy paper rockets in humid conditions. Metal was less likely to rupture catastrophically during combustion. And metal casings could be manufactured to consistent dimensions, improving accuracy and reliability.

Evidence of metal rocket casings appears in various seventeenth-century sources. François Bernier, visiting the Mughal court, witnessed rockets with metal casings at the 1658 Battle of Samugarh. Robert Anderson in 1696 proposed using metal gun barrels for rocket construction. The technology was understood; what remained was consistent military deployment.

The geographical dispersal of metal rocket development suggests that the innovation emerged independently in multiple contexts. Mughal India, with its sophisticated metalworking traditions and active military campaigns, provided one path. European artillery experiments, particularly in connection with existing metal-tube manufacturing for cannon and small arms, provided another. The technology was "in the air"—or rather, in the adjacent possible—waiting for circumstances that would demonstrate its military potential.

That demonstration came in the 1780s when Hyder Ali and his son Tipu Sultan, rulers of Mysore, deployed iron rocket artillery against British forces. The Mysorean rockets—iron tubes strapped to bamboo poles—achieved ranges of nearly two kilometers and proved devastatingly effective against tight infantry formations. British officers, witnessing this weaponry, carried descriptions back to England where William Congreve developed the rockets that would see extensive use in the Napoleonic Wars and beyond.

By 2026, the principle of metal-cased rocket propulsion has evolved into the dominant form of space launch and military missile technology. From Siemienowicz's paper rockets to Apollo moon missions to SpaceX Falcon rockets, the trajectory connects through that seventeenth-century transition from combustible to metallic rocket construction. The material change that enabled higher pressures and greater reliability opened pathways that extend to the present day.