It is now clear that the exodus of refugees from Vietnam is a highly organized, profitable racket encouraged by senior members of the Hanoi government.

Investigations here and in Asian countries playing reluctant hosts to the refugees reveal the mechanics of a traffic in which the Vietnamese authorities, Chinese entrepreneurs and would-be refugees are cooperating to serve their overlapping interests.

Respectively, each hopes to flush out southern Vietnam's large and incorrigibly bourgeois ethnic Chinese community, amass substantial amounts of gold and foreign currency in the process, and guarantee that the journey out of Vietnam is swift, without risk and made in relative comfort.

The system evolved last summer after Hanoi moved to absorb what remained of the south's Chinese-dominated private sector. The Chinese were unenthusiastic supporters of socialism, and Vietnam's split with China turned them into potential fifth columnists.

The Hanoi government set up a special department to coordinate the traffic under the control of Politburo member Nguyen Van Linh and accountable to Prime Minister Pham Van Dong.

Through tightlyknit webs of family and business contacts in Asia and the United States, the overseas Chinese have done just that. Official sources here say that all five tramp freighters that have carried refugees into Asian ports since September were chartered for this specific purpose.

Syndicates have been set up to coordinate preparations on the outside. In the case of the first three vessels -- the Southern Cross, the Hai Hong and the Huey Fong -- the central figures were ethnic Chinese who left Vietnam legally shortly after the Communist victory in 1975.

Wealthy businessmen in Vietnam, unable to export their wealth, have eagerly financed would-be refugees in return for credits paid into overseas bank accounts by relatives and friends who have already left.

Chinese middlemen working for the government made it known that exit was possible without the dangers of capture, drowning or piracy that face those who leave by small boats.

The charge for an adult reportedly is 12 taels of gold (one tael weighs 1.3 oz.) valued at about $3,500. Juveniles travel at half-price. Ethnic Vietnamese pay a 50 percent surcharge.

The money is paid to the middlemen, who in turn pay it to government officials. Refugees are allowed to take only hand luggage, the remainder of their assets being forfeited to the government.

Before the organizer's agent joins the freighter, a government official pays him the balance of gold remaining when the government tax has been levied: the government takes 10 taels, the agent two.

The system explains the contents of four oil-sodden sacks discovered last week aboard the Huey Fong, which carried 3,400 refugees into Hong Kong on Christmas Eve: gold leaf valued at $1 million.

The usual system is for the organizer's agent and his gold to be taken off the ship at sea -- the Southern Cross, Hai Hong, Tung An, and the latest arrival here, the Skyluck, carried no gold. With the Huey Fong something clearly went wrong.

But the pantomine staged by the captain, crew and 3,000 refugees aboard the Skyluck illustrates the increasing difficulties of convincing anyone that the refugees were plucked from sinking boats on the high seas.