A pilot balloon is a tool employed by meteorologists to study the movements of air currents, or wind. It is a long, cylindrical balloon that is filled with helium, and it is designed to burst upon reaching the higher levels of the atmosphere. The use of pilot balloons has strong ties to aviation, civil projects and international espionage. Also called weather balloons, pilot balloons have been used since 1783, when two Frenchmen launched a wind velocity pilot balloon to check wind conditions before the launch of the first manned balloon flight.
Pilot balloon observation is the practice of studying the pilot balloon in flight. Careful measurements are made to find the velocity of the pilot balloon and the direction in which it travels. The elevation of the pilot balloon and its azimuth angles are factored into the observations to determine wind speed and direction at different heights in the atmosphere.
Although there has been very little that has changed about the construction and design of the pilot balloon since the first one was launched, it has proven to be a very valuable tool in the study of meteorology and other earth sciences. With the use of pilot balloons, a French meteorologist named Leon Teisserenc de Bort was able to discover and prove that the earth has a troposphere, a lower level of the atmosphere where weather occurs. In the 1930s, new technology entered the scene in the form of radio tracking systems that made it possible to expand upon the usefulness of the pilot balloon and develop the science of meteorology even further.
With radio tracking, pilot balloons became more than just wind tracking tools. A variety of tools could be added to the weather balloon that allowed it to read temperatures and humidity, among other things. The use of pilot balloons for weather observation has made it possible for meteorologists to create three-dimensional maps of the atmosphere and the various weather patterns that affect the atmosphere.
In some cases, a pilot balloon is also outfitted with cameras, video equipment or telescope units to capture those rare vistas that could be seen only from the air. This has made pilot balloons a useful resource for espionage and the creation of detailed topographical maps. This use is not without its drawbacks, however. With the unique size and dimensions of pilot balloons, over the years, they have been mistakenly thought to be objects such as threats from foreign enemies, unidentified aircraft and alien spaceships.