aware of reports of severe wind shear on the final approach path (which he confirmed by radio to the final-vector controller), but decided to continue nonetheless. The NTSB published its final report on March 12, 1976, determining the following probable cause of the accident: The National Transportation Safety Board determines that the probable cause of this accident was the aircraft's encounter with adverse winds associated with a very strong thunderstorm located astride the ILS localizer course, which resulted in high descent rate into the non-frangible approach light towers. The flight crew's delayed recognition and correction of the high descent rate were probably associated with their reliance upon visual cues rather than on flight instrument reference. However, the adverse winds might have been too severe for a successful approach and landing even had they relied upon and responded rapidly to the indications of the flight instruments. The NTSB also concluded that failure of either air traffic controllers or the flight crew to abort the landing, given the severe weather conditions, also contributed to the crash: Contributing to the accident was the continued use of runway 22L when it should have become evident to both air traffic control personnel and the flight crew that a severe weather hazard existed along the approach path. Legacy This accident led to the development of the original low level wind shear alert system by the U.S. Federal Aviation Administration in 1976, which was installed at 110 FAA towered airports between 1977 and 1987. The accident also led to the discovery of downbursts, a weather phenomenon that creates vertical wind shear and poses dangers to landing aircraft, which ultimately sparked decades of research into downburst and microburst phenomena and their effects on aircraft. The concept of downbursts was not yet understood when Flight 66 crashed. During the investigation, meteorologist Ted Fujita worked with the NTSB and the Eastern Air Lines flight-safety department to study the weather phenomena encountered by Flight 66. Fujita identified "cells of intense downdrafts" during the storm that caused aircraft flying through them "considerable difficulties in landing". Fujita named this phenomenon "downburst cells" and determined that a plane can be "seriously affected" by "a downburst of air current". Fujita proposed new methods of detecting and identifying downbursts, including installation of additional weather monitoring equipment at the approach ends of active runways, and also proposed development of new procedures for immediately communicating downburst detection to