T'way Air's A330-300 passenger aircraft / Courtesy of T'way Air

T'way Air, Air Premia and Korean Air are facing safety probes from the transport ministry amid their repeated flight delays, which have caused massive inconveniences to hundreds of passengers, according to government officials and aviation industry watchers Monday.

The latest in a series of such controversies was sparked by a Korean Air flight from Incheon to Taiwan's city of Taizhong on Saturday afternoon. The passenger jet carrying 125 passengers made an emergency return about halfway through its trip, after an equipment defect was detected. The airline ended up delaying the flight to the following day.

Other airlines also caused discomfort to customers for their similar flight delays. T'way Air, a Seoul-based low-cost carrier (LCC), has particularly drawn a huge backlash for its frequent delays, raising doubts as to whether the company is qualified to launch four European routes soon. The carrier won the license as part of a precondition for Korean Air's takeover of Asiana Airlines.

T'way Air came under fire for delaying a total of five flights only for the past two weeks. The airline's flight from Osaka to Incheon on June 13 was delayed for 11 hours due to a defect.

Air Premia has also drawn criticism for its frequent flight delays. The LCC has rescheduled its overseas flights repeatedly for reasons — such as maintenance of its aircraft.

The Ministry of Land, Infrastructure and Transport issued a warning in response to their weak safety checks.

"We ordered T'way Air to come up with special safety measures to ensure safe flights and report them to the land ministry, so it can implement them in July," an official from the transport authority said.

The ministry also shared its plans to inspect the two LCCs for their frequent flight delays and slap them with relevant sanctions if they are found to have breached maintenance rules.

"If T'way Air and Air Premia turned out to have violated their duty to protect customers, they will be fined," the official said.

Officials from the aviation industry also said any carriers should come under scrutiny when causing inconveniences to customers for their weak safety monitoring.

"Repeated aircraft defects can be interpreted that the carriers have not fulfilled their duty to protect customers," an official from an airline said. "Of particular concern is that a number of carriers are mired in such scandals too frequently. Competition from existing players gets tougher amid the peak travel season, but they should be reminded that temporary sales growth without proper safety checks means nothing if they lose customers' trust."

According to the ministry, a survey — conducted among a group of 30,000 customers here — showed that T'way Air came in at ninth place out of 10 domestic carriers in terms of customer satisfaction in 2023.