The pilots of a passenger jet argued moments before it crashed last month at an Indonesian airport, killing 21 people, a senior investigator said in an interview broadcast Sunday.

The Garuda Airlines' Boeing 737-400 burst into flames after overshooting the runway and skidding into a rice field when landing March 7 at Yogyakarta airport on the main island of Java.

Chief investigator Tatang Kurniadi said his preliminary findings would point to human error as the cause of the disaster.

"I worry that this accident came from the absent-mindedness from the cockpit," Kurniadi said in the Nine Network interview.

The airliner's cockpit audio recordings revealed that the pilot and co-pilot were arguing over their speed and wing flap angles moments before the crash, Kurniadi said.

The captain and co-pilot, who were among the 119 survivors of the crash, were flying together for the first time, he said.

The captain had "enough experience" after flying more than 15,000 hours, while the co-pilot was a "young pilot" with 2,000 flying hours, he said.

The co-pilot demanded the pilot "go around" — abandon the landing attempt and make a second approach, Kurniadi said.

The pilot proceeded to land so fast that the co-pilot could only partially extend the flaps supposed to slow it down, Nine reported.

Kurniadi and his investigation team are to finalize their results within a month.

Survivors of the crash were able to escape through the exits of the burning jet.

It was the fourth accident involving a commercial jetliner in Indonesia since 2005. Experts say poor maintenance, rule-bending and a shortage of properly trained pilots may contribute to the sprawling country's poor aviation safety record.