In Miami, Southern Air spokesman William Kress denied that the company was linked to either the airplane or its crew.

"There is no connection whatsoever, " Kress said. "We don't even have that type of aircraft."

Kress said it was possible that Hasenfus or Cooper had worked for Southern Air in the past, but he said none of the crew members aboard the downed plane were current employees.

Southern Air occasionally performs maintenance on C-123s but had never worked on the plane that was shot down in Nicaragua, Kress said.

Hasenfus told the Sandinistas he had been working in Vietnam, presumably in covert supply flights, until 1972, and that Cooper had continued in similar work until the present, Calderon said.

SALVADORAN LIAISON

Calderon also showed business cards he said were taken from Cooper's wallet for P.J. Buecher, Operations Coordinator for the State Department's now-defunct Nicaraguan Humanitarian Assistance Office and Lt. Col. Humberto Villalta, commander of the Salvadoran navy.

Villalta has been named by rebel sources as an officer who has been instrumental in providing the contras with aircraft hangars and fuel, rifles, ammunition and other assistance, along with Salvadoran Air Force Commander Gen. Juan Rafael Bustillo. Calderon said Hasenfus had identified Bustillo as the direct Salvadoran military liaison for the C-123 crew.

According to Calderon, Hasenfus said the downed flight was the fourth he had made out of Ilopango, down the Pacific Coast to Costa Rica and north into Nicaragua. Calderon said approximately 15 rebel supply flights had come into Nicaragua in the past three months.

Calderon said the plane Hasenfus had intended to kick supplies out of was spotted by border guards 15 minutes before a Sandinista soldier locked on it with a shoulder-fired surface- to-air missile.

Calderon's deputy, Fifth Region army chief of staff Capt. Ramon Calderon (no relation) said in a telephone interview that the missile was a Soviet-made CM-2.

Capt. Calderon said the plane was downed by members of the Gaspar Garcia Laviana Light Hunter Battalion, of the 55th Infantry Brigade, headquartered in Juigalpa, the capital of Chontales province.

CHARRED REMAINS

Light hunters are counterinsurgency battalions, usually of about 500 or fewer troops, that operate from forward supply posts. They are heavily used in the Chontales-Boaco-Zelaya central front area.

Reporters who traveled to the crash site Tuesday said only the charred, almost unidentifiable remains of three men were found by the plane's wreckage. Only the first two letters of the craft's registration number were still visible, they said. Calderon cited its registration as C-824.

Hasenfus, a reported parachute enthusiast, made use of one to drop to safety.

The flight -- and Hasenfus -- yielded "quite a bit" of new intelligence information about contra operations, intelligence chief Wheelock told The Herald. Lt. Col. Calderon said the crash yielded "a great number" of documents now being analyzed by Sandinista intelligence.

Saul Arana, head of the Nicaraguan Foreign Ministry's North Americas section, said that Hasenfus' mission was "illegal, " but that the Sandinista government had not yet determined whether to formally charge him with a crime.

Alberto Fernandez, spokesman for the U.S. Embassy in Managua, said the embassy's deputy chief of mission, John Moderno, delivered two diplomatic notes to the Nicaraguan Foreign Ministry Tuesday requesting identification of the crash victims and consular access to Hasenfus.

Arana said Nicaragua was not required to answer the note immediately but probably would today. He said Hasenfus would receive all normal diplomatic considerations.

Calderon said Hasenfus told Sandinista officers that Gen. Bustillo had coordinated flights of five contra aircraft -- two Fairchild C-123s, two De Havilland DCH-4 tactical transports and a single-engine Cessna 180.

Wheelock also said the Sandinista army had information that the Salvadoran-based crews on contra supply flights were mostly Filipinos with some Rhodesians.

The episode also brought some celebrating from the Sandinista military, officials said.

"The more gringos there are, the more are going to fall, " said regional chief of staff Capt. Calderon.

Even with $100 million in U.S. aid expected to begin flowing soon, he added, the plane will be "one more expenditure they (the rebels) will have to make."