U.S. civilian and military specialists watching the Falkland Islands crisis believe Britain probably will land forces on the islands soon in an effort to drive Argentina toward a negotiated solution more acceptable to London.

These specialists do not feel the British are likely to launch an all-out frontal assault involving thousands of troops against Port Stanley, the island capital and main Argentine military stronghold. Rather, the British probably will put troops numbering in the hundreds ashore elsewhere on the islands and raise the British flag somewhere over the disputed territory.

Although the Royal Navy has several major warships already around the islands, including the aircraft carrier Hermes carrying about 1,500 Royal Marines, a further force of amphibious ships with about 3,000 more troops is said to be on its way, though still at least a few days' sailing time away.

Specialists here say some British marines could be put ashore now, using helicopters and Harrier jump jets for protection. But others believe any significant ground action will probably await the arrival of the amphibious ships, which reportedly are now southwest of the Tristan da Cunha group of islands in the mid-South Atlantic.

Several well-placed officials estimated that the British have only a few courses of action open in the next three weeks or so because of increasingly severe winter weather in the area. Indeed, these officials say within two or three weeks both sides could be hurting severely because of the cold and the sizeable costs of the faceoff.

The cutting-off of supplies could also begin to take a toll on the 1,800 islanders, mostly of British stock, which could also become a factor pushing London toward negotiations.

Sources here indicate that Argentina probably has 7,000 or so troops dug-in on the Falklands, a number considerably smaller than the 10,000 to 14,000 troops estimated in some accounts.

Because of the several hundred miles of coastline of the islands, specialists say it would be virtually impossible to stop a British landing, certainly on the deserted western side of the islands and even one that came reasonably close to the main Argentine garrison at Stanley.

Last week, the British are understood to have landed a small team of commandos equipped with sensitive electronic listening devices to carry out reconnaissance on the island and intercept communications between the mainland and the Argentine defenders on the Falklands.

Once ashore, it is assumed that the larger landing force would harass the island's defenders, blow up facilities, capture officers, raise the flag and perhaps establish a beachhead for still larger forces to follow.

By using hit-and-run tactics and helicopters, the British could force the Argentine defenders to come out and try to find them, causing a further depletion of supplies for the defenders on the already isolated island.

Such activites would fit into what officials here see as an "overall demoralization" plan meant to increase the psychological pressure on Buenos Aires.

Last weekend, British planes, in a surprise attack, bombed the airfield at Stanley as part of a move to prevent aerial resupply from the mainland. The British naval blockade prevents resupply by sea unless the Argentine Navy seeks to challenge the British fleet.

Although the British have claimed the air attacks "severely damaged" the airfield, other sources say there are indications the destruction was not complete. But the British could strike again.

Although the British, according to U.S. officials, are not making known their plans to Washington, there is a widespread feeling here that the British "cannot sit tight," as one official put it, especially with thousands of troops bobbing around in flotilla ships. "They've got to keep on registering victories."

Yet the view is also widespread here that London does not want to undertake any operations that would result in high casualties, either to its forces, the local defenders or island inhabitants.

But the problem with the so-called demoralization plan, as viewed by Latin specialists here, is that the Argentinians' frame of mind is such that the more humiliation they endure the more determined they become to try to strike back.

"The Argentines are looking for a victory," one official here said, and the Navy leadership is both the most militant element of the junta running the country and also the service "most looking for trouble."

There are also indications that the United States is not accumulating a great deal of immediate intelligence about what is going on in the region, which is far from the traditional areas that the U.S. keeps watch upon.

The U.S. does have satellites passing over the area, but bad weather is said to hamper those spy-in-the-sky, picture-taking devices. Most of the intelligence is understood to be picked up by monitoring electronic and radio communications of all sides.

American help to the British has consisted of sharing intelligence information, providing communications and fuel for vessels and aircraft using the American-operated airfield on British-owned Ascension Island in the South Atlantic.

Now, U.S. officials say additional American aid could come by using huge C5A jet transports to ferry equipment from Britain to Ascension and providing such things as weapons, radars and other equipment if London asks for it.

The British are said to have set up a conveyor-belt type supply system with perhaps 75 ships that now make up the fleet involved in the operation. Supply ships leave Ascension, resupply the fleet near the Falklands 3,500 miles away, then turn around and head back to Ascension for another round-trip.