Mobile Why Did Mobile Phones Work On Airplanes In The US On 11Sept01?

Why did mobile phones work on airplanes in the US on 11Sept01? - mobile

Why do cell phones work in New York and Pennsylvania on 11Sept01, the anniversary of the end of the last Arab crusade in Europe, and not before or after? The technology for the use of mobile phones on board aircraft is new and even tested the signal must be transferred pushed to have a ground station. So why not in this day and not on other days?