An Austrian pilot was killed and his German passenger severely injured when their plane crashed into a field in Thailand on Saturday.

Austrian captain Stefan Molnar, 50, and his friend Christian Leonardo Schuf, 51, were flying in the two-seater X Air Hawk aircraft registered U-H77 when it nosedived into a pasture in Chonburi province on January 13 morning.

Shocked locals said they saw the plane plummeting to earth in a tailspin before crashing into a large tamarind tree, scattering debris across the field while its left wing was snagged on the branches.

Police and rescue paramedic volunteers received a report at around 9 am and went to cordon off the scene.

They found Stefan already dead in his seat, his body mangled in the wreckage, while Christian suffered a broken ankle and bones protruding from both of his legs. He was rushed to the Wat Yan Sang Wararam Woramahawihan Hospital.

Sommit Kedjae, 64, a farmer working near the pasture, said: 'I was tending to my cows when I saw the plane gliding across the sky. There was an explosion, and plane parts fell and nearly hit me. After that, the plane fell to the ground and crashed against the tree.'

Authorities said the men had taken off from the Eastern Flying Club airport in Pattaya some three kilometres from the crash site at 8:30 am. They said both of them had licenses and were experienced pilots.

Another pilot told local reporters that the victims were due to land at an airport in Huay Yai for a Thai Children's Day activity that afternoon. He said he learned about the accident when he showed up at the venue with the plane still missing.

Police said they were coordinating with the Aircraft Accident Investigation Committee of Thailand to investigate the crash.