A Dutch court has sentenced a former F-16 fighter pilot to five years in jail for trying to sell state secrets to a Russian diplomat.

"The court today sentenced the 37-year-old former fighter pilot to five years in jail," The Hague district court said in an online statement.

It was proved that the former airforce captain, named only as Chris V, by the Dutch media, "had secret documents on a computer and on CD-ROM... and was preparing a deal to sell it to a foreign power in return for a considerable amount of money."

The Hague court said the ex-aviator contacted a Russian military attache and was trying to sell secret information in return for 500,000 euros (U$650,000) when he was arrested on March 17.

The documents particularly contained information about secure radio frequencies and the tactical handling and detailed characteristics of the F-16 in combat situations.

The Russian diplomat and the pilot met several times, according to the court, including at a hotel and a restaurant in a seaside suburb of The Hague.

The former captain left the Dutch Air Force in 2010, where he served for 13 years, including combat experience in Afghanistan, said the statement.

According to Dutch daily tabloid De Telegraaf, the pilot was in financial difficulties at the time of his arrest.

"Therefore the suspect, purely for his own financial gain to help him out of his financial crisis, put himself above the safety concerns of the state and his fellow citizens," the court added.