PTT Aviation has a base at Leeds Bradford Airport offering training and experience flights in light aircraft and helicopters. It also operates from Durham Tees Valley and Newcastle airports.
A notice has now appeared at the site stating that the company has entered voluntary liquidation.
Its fleet of aircraft have now been grounded and cannot leave the airport.
The date of liquidation has been given as September 3, when insolvency specialists Clark Business Recovery, who are based in Leeds, are formally appointed as creditors.
It is not yet known whether a buyer will be sought or whether the flight school's assets, including its aircraft, will be sold off.
In November 2016, PTT's staff at Leeds Bradford gave a lengthy interview to the Yorkshire Evening Post in which they expressed their hopes that global airline expansion of airlines would create increased demand for commercial pilot training.
As well as providing basic flight training for amateurs hoping to gain a private flying licence, the instructors also offered more advanced tutoring to those looking to qualify as commercial pilots.
They sold trial flight experience packages, which were marketed as ideal birthday gifts, for Â£125.
The company's website has been taken offline and information on how customers with flight bookings can obtain refunds has not been released.
Leeds Bradford Airport chose not to comment on the situation.
In September 2017, passenger airline Monarch collapsed and its two aircraft based at Leeds Bradford Airport were both grounded before being sold or leased to other operators.