Pilots use their expertise to calculate wind speed, where they are spraying, spray droplet size and other factors that affect the drift of spraying. The new technology uses a computer to calculate the factors and tell the pilot exactly where to spray. This computer takes all the same readings that the pilot did, and calculates them extremely quickly. Sykes said science and weather are major components of mosquito abatement. Air temperature and wind velocity are both extremely important to pilots.
Wind velocity is different at ground level than at higher altitudes, and can change quickly.
Wind can also be blowing one direction on the ground, and a different direction up higher. A weather balloon was sent up to 200 feet, with a computer attached to the balloon. The wind at 200 feet, the altitude at which the pilot would be flying, was a gusty 15 mph. To test the computer against the pilot, a row of cages filled with mosquitoes was set out, and two passes by the airplane were made. On the first pass, Janssens used his experience to calculate where to spray so that an optimum number of mosquitoes would be killed by the spray, and the spray would not be wasted.