Tuesday, June 14, 2005

Beginnings

Historically, rockets were first developed by the Chinese some accounts put this as early as B.C. 300, using gunpowder; but most accounts put this nearly 1000 years later. These were initially developed for entertainment, the precursors to modern fireworks, but were later adapted for warfare in the 12th century. Because the pressures on the rocket walls are lower, the use of rockets in warfare preceded the use of the gun, which required a higher level of metal technology. It was in this role that rockets first became known to Europeans following their use by Ottomans at the siege of Constantinople in 1453. For several more centuries they remained curiosities to those in the West.
Siemenowicz multi-stage rocket, from his Artis Magnae Artilleriae pars prima Since mid-17th century, for over two centuries the work of Polish-Lithuanian Commonwealth nobleman Kazimierz Siemienowicz, "Artis Magnae Artilleriae pars prima" ("Great Art of Artillery, the First Part". also known as "The Complete Art of Artillery"), was used in Europe as a basic artillery manual. The book provided the standard designs for creating rockets, fireballs, and other pyrotechnic devices. It contains a large chapter on caliber, construction, production and properties of rockets (for both military and civil purposes), including multi-stage rockets, batteries of rockets, and rockets with delta wing stabilizers (instead of the common guiding rods). At the end of the 18th century, rockets were used militarily in India against the British by Tipu Sultan of the kingdom Mysore which resulted in resounding victory against the British in the first Mysore War. The British then took up the practice and developed them further during the 19th century. The major figure in the field at this time was William Congreve. From there, the use of military rockets spread throughout Europe. The rockets' red glare helped to inspire the US national anthem. Early rockets were highly inaccurate. Without any spinning up of the rocket, nor any gimballing of the thrust, they had a strong tendency to veer sharply off course. The early British Congreve rockets reduced this tendency somewhat by attaching a long stick to the end of a rocket (similar to modern bottle rockets) to make it harder for the rocket to change course. The largest of the Congreve rockets was the 32 pound (14.5 kg) Carcass, which had a 15 foot (4.6 m) stick. Originally, sticks were mounted on the side, but this was later changed to mounting in the center of the rocket, reducing drag and enabling the rocket to be more accurately fired from a segment of pipe.
Robert Goddard and his first liquid-fueled rocket The accuracy problem was mostly solved in 1844 when William Hale modified the rocket design so that thrust was slightly vectored to cause the rocket to spin along its axis of travel like a bullet. The Hale rocket removed the need for a rocket stick, travelled further due to reduced air resistance, and was far more accurate.

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