A passenger on a plane caught a gigantic UFO

On August 15, 2015, a passenger on a plane was travelling over an area in Central America when he has spotted a gigantic UFO through his window. Witness has taken several photo of this object.

Witness statement:

Was returning home from Costa Rica, flying north possibly over Nicaragua at roughly 40,000 feet, when I saw what was a gigantic craft, not an airplane, as I had seen many airplanes on this trip and can positively identify an aircraft, moving slowly across the sky. It looked to be hundreds of feet across, about a mile long. I started taking photos of it as it moved across the sky. I kept trying to identify it, but the rate of speed and odd shape defied my identification ability. I have a series of 9 photos I took of the object. The pictures show it changing shapes. Not sure what it means.