Gaikwad, who was at loggerheads with the airline after he thrashed one of its officials, boarded the New Delhi-Mumbai Central Rajdhani Express as he did not receive official communication about lifting of the ban, they added.
According to a railway official, the parliamentarian boarded A1 coach (seat number 41, second AC) of the express.
"Gaikwad had booked the ticket in advance. Since he did not receive official communication regarding lifting of the travel ban, he took the train as decided earlier," a source in the know of the things told PTI.
"He already had train ticket booked in his name. Plus, the ongoing Parliament session will conclude on April 12. Why would he book flight ticket for April 17?" the source asked.
Air India today revoked its flight ban on the MP with immediate effect, two weeks after Gaikwad assaulted an airline staffer onboard a plane.
The 56-year-old Osmanabad MP had yesterday written a letter to Minister for Civil Aviation Ashok Gajapathi Raju expressing his "regrets" over the "unfortunate incident" on March 23.