More than 500 Honduran troops parachuted from U.S. transport airplanes to a site on the outskirts of a Miskito Indian refugee camp here today as part of a major joint maneuver aimed at preparing Honduras for the possibility of war with Nicaragua, less than 25 miles away.

The eight-day exercises, called Ahuas Tara (Big Pine in the Miskito language), is designed to avoid outright confrontation with Nicaragua. Both military and civilian officials avoid mentioning even the name of the nation to the south if possible.

But according to U.S. diplomats in Honduras, the maneuvers are intended to send a strong, if delicately balanced political message, to both the revolutionary leftist regime in Managua and the government that Washington backs in Tegucigalpa, the Honduran capital.

"The stated goal is to evaluate the military readiness and capability of the Honduran armed forces, and that really is one goal," said a U.S. diplomat who asked not to be cited by name. "The political goal is to show that we will defend our allies in Central America."

Yet senior U.S. officials also point out that there is no written commitment to this effect, and the Hondurans, even the field commanders conducting these maneuvers, seem unsure of how much they can rely on U.S. resolve in this war-torn region.

The deputy commander of the 4,000 Honduran troops involved in the exercise, Col. Humberto Regalado Hernandez, said after the airborne "assault" that nothing like it could have been carried out without the presence of American support personnel and particularly the 10 American C130 transports. The Hondurans "have to see" if such aid is really available in the event of a war, Regalado said.

The maneuvers were planned last summer, according to one senior American official, when the politically powerful commander of the Honduran armed forces, Gen. Gustavo Alvarez, was showing increased interest in reducing his Army's ties to the United States.

Argentine influence, according to diplomatic sources, was growing. Reassurances made to Honduran President Roberto Suazo Cordova, including this exercise, have helped renew Washington's always extensive influence with the Honduran military, these sources said.

Nicaragua's Sandinista leaders have charged that the maneuvers may be used as cover for the resupply of rebels fighting to overthrow them, or even as preparation for an actual invasion. U.S. and Honduran officials, including President Suazo, repeatedly deny such intentions.

On a two-day tour to this isolated region of eastern Honduras to observe the exercises, conducted by the U.S. Embassy and the Honduran government, it was impossible for more than 70 foreign reporters and several foreign military attaches to determine whether the Nicaraguan concerns are justified or not.

The focus of the exercise as officially presented is the defeat of a small-scale invasion. It has sometimes appeared that the Nicaraguans might move against base camps of anti-Sandinista rebels operating out of Honduran territory.

The Nicaraguans repeatedly have charged that Mocoron, the refugee camp here with more than 10,000 embittered Miskito Indians forced out of their homes by the Sandinistas, is at least a recruiting area for "counterrevolutionaries."

Some of the heaviest fighting in a real war between the Sandinista troops and the forces trying to overthrow them has taken place just south of here, on the Nicaraguan side of the Coco River that marks the boundary.

Refugees continue arriving in Mocoron, with the latest group of 300 coming from Nicaragua two weeks ago. Some of those same Miskitos stood and watched in awe today as 528 Honduran paratroopers floated to earth about half a mile from the camp before moving to "rescue" a theoretically besieged battalion at Dursuna to the southeast.

"This is really good," said Randal Reyes, standing with a primitive bow and arrow he uses for fishing. Next to him was an $8 million American UH60 Blackhawk helicopter used in the exercise.

Although supplies and 1,600 U.S. support personnel have been arriving in Honduras for weeks, the operation did not begin in earnest until yesterday, when a "Red Army" regiment attacked Honduras' "Blue Army" from an imaginary country called Corinto, said to be about where Nicaragua is.

The Reds "took" the Atlantic town of Puerto Lempira and the camp at Mocoron, and surrounded the thousand-man unit at Dursuna. As the scenario developed, according to the U.S. commander of operations Col. William Comee and other officers, the Honduran president called for support from friendly countries and the United States answered his plea.

With the arrival of 13 American helicopters, two of the U.S. Navy's landing-craft docks off the coast and at least 80 sorties by U.S. transport planes, four Honduran battalions will succeed in rolling back the imaginary red tide and securing the imaginary border by Thursday night.

Although Comee took pains to say that the "Red" forces are not the same as the Nicaraguan Army, which is armed and trained by the Soviet Bloc, the imaginary "Reds" are supposed to have a limited supply of Soviet-made Mig17s--such as the Nicaraguans have hoped to acquire. The Red Army also has shoulder-launched antiaircraft missiles, which the Nicaraguans possess.

The Honduran operational commander, Col. Roberto Martinez Avila, said the drop seemed to have gone "very well."