"He is a nice guy, a good guy, never had any problem with anyone," said Nik Huzlan, who went to flight school with Zaharie in 1979. They later joined Malaysia Airlines together.

"He was a good student back in the flight academy, and failed no exam," he said. "He is a normal person. Being normal means he goes out socially, has friends and doesn't fight with people, just like any normal person. I never saw anything unusual in him."

After flying Boeing 777s for more than 10 years, Nik, 55, retired from Malaysia Airlines two and a half years ago.

Nik said that as far as he knows, Zaharie had no discipline problems on the ground or in the air.

As a pilot with 18,365 flight hours under his belt, Zaharie joined Malaysia Airlines in 1981 before embarking on a sterling 33-year career. He has flown Boeing 737s, Fokker F50s and Airbus A300s for the airline.

In addition to being a veteran pilot, Zaharie was certified by Malaysia's Department of Civil Aviation as a simulator test examiner, Malaysia Airlines officials said.

Pictures have surfaced with Zaharie in a T-shirt with the slogan "Democracy is Dead", raising fears he could have hijacked the plane as an anti-government protest.

"It is difficult to believe the crew member, especially the two pilots in the front, hijacked the plane, because Captain Zaharie is in the peak of his career. He's got money and a good life. He has no reason to lose it," he said.

As for reports that suggest a link between Zaharie and al-Qaida, Nik said he doesn't know anyone from pilot school who was in al-Qaida. "It was the 1980s, there wasn't much al-Qaida at that time, and everyone I know joined MAS. And I don't think he would commit suicide. He is a good person and lives a good life.

"If he wanted to commit suicide, he would do it himself rather than crashing a plane with more than 200 people," he said.

Nik said he doesn't know much about Zaharie's politics. "But I don't think a pilot would crash a plane just because he is upset," he said.

As for the flight simulator found in Zaharie's house. Nik said it is not unusual. At Malaysia Airlines, pilots are tested on the simulator twice a year, and those who fail lose their jobs, he said.

"Maybe he wanted more practice at home. It might cost $3,000, which is affordable for him," Nik said.

"I haven't seen him for a while. We have our families and different hobbies. He likes to fly the parachute and remote control helicopters."

On the morning of March 8, he heard the news. "I was very, very shocked, because Malaysia Airlines is safe. I had a good time working for MAS. It is still safe today. My wife is still flying with a Malaysia Airline Boeing 777 as a chief attendant," he said.

"All the communication is cut off - that is very unusual. I think the plane was under control but flew somewhere else."

As for a picture of the co-pilot and two young women in the cockpit, Nik said, "If a person asks to take a picture with the pilot, the pilot usually says yes.

"When an airplane disappears, it is easy to blame the pilot and ignore that problem. It is not fair for those who are not here to defend their names."

He said he was disappointed with the investigation, and that it could have been handled better. However, with cooperation with the US and China, there will be a result, Nik said.

"I can only hope for the best," he said. "If he survived this incident, I would ask him, "Why didn't you find a way to send out a signal?"

Contact the writers at pengyining@chinadaily.com.cn

Timeline

Day 10 major developments:

8:30 am: Five Asian nations say their radar systems have not detected any sign of the Malaysia Airlines plane, which could help narrow the search.

11:10 am: The US navy P-8A Poseidon, the US military's most advanced maritime surveillance aircraft, has joined multinational search efforts, The Wall Street Journal reports.

1:51 pm: Malaysian police are investigating a flight engineer who was among passengers on the plane as they focus on the pilots and anyone else on board with technical flying knowledge, Reuters cites senior police official as saying.

2:08 pm: Australia has agreed to a request from Malaysia to take charge of the "southern vector" in the search for the jet, Reuters reports Prime Minister Tony Abbott as saying.

2:38 pm: Search and rescue efforts now involve 26 parties, with French aviation investigators arriving to help, The Wall Street Journal cites the Malaysian Transport Ministry as saying.

4:44 pm: Chinese Foreign Ministry spokesman Hong Lei says China's search for the jet will no longer be focused on the South China Sea. Authorities will adjust their plans when they receive new information from Malaysian officials.

- China Daily