This is the first time that Patel has appeared before the financial probe agency in connection with the case.
Patel appeared at the ED headquarters in South Delhi's Khan Market area.
The former Minister had skipped ED questioning on June 6 and asked for a next date for questioning citing prior commitments.
The ED is probing the Air India-Indian Airlines merger; purchase of 111 aircraft from Boeing and Airbus at Rs 70,000 crore; ceding of profitable routes and schedules to private airlines; and opening of training institutes with foreign investment.
It is also investigating how the money received in Talwar's accounts were transferred to government employees, including those in the Civil Aviation Ministry.
(This story has not been edited by Business Standard staff and is auto-generated from a syndicated feed.)