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The development of the Modern Hot Air Balloon

The modern hot air balloon is constructed by suspending a wicker basket underneath a large bag of nylon fabric, known as an envelope. The wicker basket carries the balloon’s pilot, any other passengers, and the propane tanks that provide the balloon with a source of fuel. The propane tanks are connected by hose to a pair of burners, which are located between the basket and the envelope. When the burners ignite, their heat passes through the balloon’s skirt—a circular sheath of fire-resistant material at the mouth of the envelope—and finally into the envelope itself. Located at the top of the envelope is a parachute vent, a mechanism that allows the pilot to release hot air and increase the balloon’s rate of descent when required. This is controlled by a parachute valve cord that extends through the balloon, and into the basket. The use of hot air balloons can be traced back to the Three Kingdoms era of Chinese history (220-280 AD). Zhuge Liang used these early incarnations, known as Kongming lanterns, as military signals. The first manned flight on record took place in France on October 15th, 1783. In a balloon constructed by Jacques-Etienne Montgolfier, a Frenchman named Pilatre de Rozier was elevated eighty feet off the ground. Modern hot air balloons, with their capacity to ascend or descend and occasionally ‘steer’ at the pilot’s will, were first developed by Ed Yost in the 1950s. The Bristol Belle is generally regarded as the first modern hot air balloon, and had its inaugural flight in 1967. Since then, balloon technology has become extremely sophisticated. Some hot air balloons have reached altitudes of 21,000 metres, travelled over 7,500 kilometres, and reached speeds of up to 400 kilometres per hour. Hot-air ballooning is generally a safe activity, and serious accidents are rare. In the event that something does go wrong, several items of safety gear are useful to have on board. In case the pilot light and the auxiliary piezo ignition fail, it is a good idea to have a welding torch flint sparker available for the pilot’s use. Given the propane combustion used to propel the hot air balloon, a fire extinguisher is an absolute necessity. Flame-resistant gauntlets made out of either leather or nomex are required for the pilot so that a gas valve can be disabled even if an open flame is present. While nomex is a specially-manufactured synthetic form of fire-retardant material, synthetic clothing is generally a hindrance to fire safety, and clothing made of natural fibre is a superior option for pilots. Finally, a handling line—a long rope that can be thrown overboard is a vital precautionary measure that allows people on the ground to steer the balloon away from trouble. To ensure balloon longevity and safety in operation, it is vital that hot air balloons be maintained and repaired while not in use. Keeping the envelope clean and dehumidified is an important The burner and fuel system also requires regular maintenance. step that prevents mould from forming on the fabric. This is especially important if the balloon has landed in a wet or muddy environment. This can involve the replacement or repair of damaged hoses and any sticking or leaky valves. The wicker basket has skids on its bottom to help it gain traction upon landing; over time these are worn down, and will need to be replaced. International regulations stipulate that balloons must be given a full inspection every one hundred flight hours, or twelve months. This ensures that any problems can be rectified before they become hazardous.