Not heard of any connection myself. My textbook doesn't even list any aetiology. (Aetiology= the science of cause of disease.)
Had a quick look on medical databases, and again no association between aircrew and renal cancer.
There is some connection between living near Chenobyl, and renal cancer- apparently Caesium exposure doubles the incidence.
If you want to have a search of a thorough medical database, try
http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?CMD=Search&DB=PubMed
Be prepared to spend a little time learning the system !