christopher wheeler , 54 , worked at the exclusive tower hill in delaware .
police discovered 2,000 indecent images on his computers in october 2013 .
composer and pilot was found guilty of multiple sex offences in december .
he was headmaster for nine years and earned around $ 370,000 a year .
his attorneys claim the court tried to paint him as ` mr filthy '
elite school was founded in 1919 by members of the du pont family .
past graduates include us senator chris coons and tv personality dr oz .