New Delhi, June 13 -- Former civil aviation minister Praful Patel on Wednesday again skipped questioning by the Enforcement Directorate in connection with an investigation into how Air India ceded profitable routes to private airlines. Patel, who was questioned on Monday and Tuesday for over 17 hours, skipped the questioning after sending a letter to the agency through his advocates. The Nationalist Congress Party (NCP) leader had skipped ED questioning on June 6 too, citing prior appointments....