KOLKATA: Fliers may soon have to furnish their Aadhaar card number to book tickets Jet Airways has already recommended insertion of the 12-digit unique number in the PNR when tickets are booked. Sources said other airlines would follow suit. Though it was a recommendation now, it would soon become mandatory, sources said.Indian Railways has already announced Aadhaar details will be required while claiming concession on train tickets.Jet Airways has claimed Aadhar-linked PNR will ensure seamless service to fliers. Airport systems will be developed to recognise the number in the bar code and allow fliers to enjoy express service. The airline website has gone live with the acceptance of Aadhaar number at the time of booking. Web and mobile check-in boarding passes will be integrated later.But the travel trade fraternity is worried the move could lead to fears of snooping by tax authorities and lead to curtailing of travel. “The moment Aadhaar card is linked, it will get connected with the travellers' tax and bank account,“ said a tax consultant. Travel Agents Federation of India (east) chairman Anil Punjabi felt the move would create apprehension. “With the government introducing new rules nearly every day , travellers will be apprehensive. When you ask for personal details, people become wary,“ he said.