Yes, felony convictions can prevent you from becoming a pilot and/or remaining a pilot once you’ve completed training. The FAA has even refused to issue medical certificates for student pilots because of felony drug convictions. Substance abuse and being branded a security threat are common reasons for FAA denial. Although felons are not strictly barred from becoming pilots, the FAA has leeway in denying licensing. Good moral character is an expected character trait of pilots. If you are unsure about your felony conviction, contact the FAA.