JAKARTA -- Indonesian investigators examining the cause of the Lion Air flight 610 that crashed last month sought to clarify widely quoted comments made this week that the aircraft had not been fit to fly.
The country's air safety authority on Thursday insisted that the investigator quoted at the publication of preliminary findings on Wednesday had not said the aircraft was not airworthy.
However, Indonesia's National Transportation Safety Committee, or KNKT, also said it would not change its preliminary findings that the aircraft had experienced problems on its previous flight that had rendered it "un-airworthy." It said in the report that the flight the day before the crash should not have been continued.
The denial of comment on Thursday by KNKT comes a day after Lion Air vehemently objected to KNKT's claims on Wednesday night. Edward Sirait, president director of Lion Air, then threatened legal action against KNKT if it did not clarify its comments.
Lion Air was established in 1999 by brothers Rusdi and Kusnan Kirana. Rusdi was an adviser to President Joko Widodo and now serves as Indonesia's ambassador to Malaysia.
Flight 610 crashed on Oct. 29, a mere 13 minutes after takeoff from Jakarta on a scheduled one-hour flight to Pangkal Pinang on the island of Bangka. All 189 passengers and crew were killed. Investigators said at a press conference on Wednesday that the aircraft should have been grounded on its penultimate flight from Bali to Jakarta the previous day, after it experienced the same problems as the ill-fated flight.
"In our view ... the plane was not airworthy," KNKT investigator Nurcahyo Utomo said Wednesday. "The pilots should not have resumed the flight."
A press release issued by KNKT on Thursday said: "We would like to highlight that KNKT and/or the head of aviation investigation subcommittee never stated that Lion Air aircraft, Boeing 737-8 (MAX) registration PK-LQP, [was] not airworthy." The statement referred specifically to the flight originating from Bali and the fatal crash the next day.
Utomo, speaking at a press conference, said that on both the flights, the aircraft had been cleared to fly after passing tests and relevant documents were signed.
David Yu, adjunct professor of finance at New York University Shanghai, said that if the aircraft was officially deemed not airworthy, it "would create even more negative perceptions." He added: "There is a host of mitigation action options that can be implemented by the aviation authorities affecting some or part of the airline activities."
KNKT's Thursday statement contradicts its safety recommendation to Lion in its preliminary findings. It had said that the flight from Bali to Jakarta "experienced stick shaker activation" throughout the journey that made it not airworthy.
"Stick shaker activation" refers to "a warning that tells the aircraft [it] is on the edge of losing its flying capabilities in a matter of seconds," according to a person who previously worked on Lion's safety. He added that it would have been suicidal for the pilots to continue the flight, and the crew "must have" tried to turn back to land.
The Oct. 29 crash was the first fatal accident for Lion Air since a failed landing in 2004 in Solo, a city in Central Java Province that killed 25. The budget airline has a spotty safety record, having had a series of minor incidents that included runway overruns.
KNKT will continue its investigation into the crash, including the search for the cockpit voice recorder, which could provide further clues as to the cause of the accident. A full report is scheduled to be released next October.
Nikkei staff writer Bobby Nugroho contributed to this article.