I heard of a pilot who went for his ATP license checkride. The examiner looked through his logbook to see that he had the proper experience.
The examiner came upon some entries for a particular aircraft. In fact quite a few entries. He questioned the pilot about them and was not satisfied with the answer. Then he told the applicant that the aircraft in question was his personal aircraft and that he had never seen the applicant in the past and certianly had never given him permission to fly his personal aircraft, so how was it that he had several hundred hours logged in that airplane?
Needless to say the applicant was speechless.
The examiner declined to give the applicant a checkride and reported the facts to the local FAA office. I do not know what they did about it but I am sure it was not a favorable outcome for the applicant. I bet he lost all of his certificates and had to start over again!
I bet the applicant saw that aircraft flying on a certain day and so he took it upon himself to "log a few hours" in it as no one would find out it was not him flying it.
Bill