While at O’Hare airport photographing aircraft landing I always like to look up to see if there is anything interesting flying by at high altitude, and I saw a large contrail and took this shot:
I didn’t get the shot while it was overhead due to I was taking a picture of a United Airlines 787 landing at O’Hare.
To get a better idea the size of this aircraft here is a shot of a Dreamlifter at the Rockford Airshow 2012: