The United States has no spy satellites operating over the Falkland Islands or Argentina and could not give Britain such intelligence information even if it wanted to, administration officials said yesterday.
The officials also added that no U.S. reconnaissance planes or drones have been sent over Argentina or the Falklands to take photographs of troop deployments or ship movements. Such information would be helpful to the British military effort.
These assertions, given to reporters on a not-for-attribution basis, are part of President Reagan's effort to persuade Britain and Argentina that the United States is not tilting toward either nation as it tries diplomatic avenues to defuse the Falklands crisis.
While refusing to talk publicly about U.S. satellite coverage, Pentagon spokesman Henry E. Catto Jr. did tell reporters at a briefing yesterday that the United States is "not engaged in aerial reconnaissance in that part of the world." He said he was referring to Argentina and the Falklands.
After the formal briefing, Catto told reporters his term "aerial reconnaissance" referred to "air-breathing" aircraft. He added that he cannot discuss U.S. and Soviet satellites whirling above the Earth.
However, U.S. officials confirmed again yesterday that the Reagan administration is allowing Britain to use U.S. facilities to communicate with Royal Navy submarines. But they said the communication satellite channels being used for this purpose and other assistance are nothing more than the Royal Navy normally receives as part of North Atlantic Treaty Organization operations.
British nuclear-powered attack submarines, armed with torpedoes, are the spearhead of the blockade London has imposed for a distance of 200 miles around the Falkland Islands. The subs are deadly against freighters, aircraft carriers and, under certain conditions, even destroyers but have a hard time stopping small, fast patrol boats.
Argentina said Wednesday that two of its 90-foot patrol boats had zipped through the blockade area Tuesday and tied up at a Falklands port without being challenged.
The British subs zero in on the noise made by surface ships, particularly the turning propellers.
A submariner with headphones can tell by listening to propeller rotation what kind of ship it is, how far away it is and in what direction it is headed. The submarine pinpoints the ship's location by triangulating underwater sounds as its quarry steams along.
When a ship is located, the submarine sneaks into killing distance, usually between two and 10 miles for modern subs such as those in the British Navy armed with long-reach torpedoes. The submarine can rise near the surface to raise its periscope and check on the type and nationality of the ship. The sub can even risk surfacing to warn the vessel to leave the blockaded zone.
If a British submarine skipper decided to try sinking an Argentine ship, his major weapon would be the highly regarded Tigerfish torpedo, with a range of about 18 miles.
The Tigerfish propels itself through the water while leashed to the submarine by an unwinding coil of thin wire. An operator watching the Tigerfish's track on a screen inside the submarine steers the torpedo into the target through signals sent through the wire.
When it nears the ship, the Tigerfish emits its own radio waves, which are supposed to bounce off the target. To make the kill, the Tigerfish homes in on those sound waves bouncing off the ship.
If the Tigerfish misses and an Argentine escort destroyer rushes toward the submarine to try to sink it, today's modern subs are so fast--top speed about 30 knots--that they can outrun most pursuers.
Submarine specialists said that the Argentine Navy has little chance of sinking a British sub and that from four to six attack subs could do a good job of enforcing the announced blockade. Britain has not said how many subs are in the area, although at least one is thought to be there.
However, they added, it is no real trick for Argentine patrol boats to to race through the blockade zone before submarines have time to locate them by sonar and fire torpedoes at them. On the other hand, Argentine patrol boats could do little about adequately supplying Argentine troops on the Falklands if shooting starts.