Israeli attack on USS Liberty (US Navy ship)

Israeli attack on USS Liberty (US Navy ship)
The USS Liberty incident was an attack on a U.S. Navy intelligence ship, USS Liberty, in international waters about 12.5 nautical miles (23 km) from the coast of the Sinai Peninsula, north of El Arish, by Israeli fighter planes and torpedo boats on June 8, 1967.



It occurred during the Six-Day War, a conflict between Israel and the Arab states of Egypt, Jordan and Syria. The Israeli attack killed 34 U.S. servicemen and wounded at least 173. The attack was the second deadliest against a U.S. Naval vessel since the end of World War II, surpassed only by the Iraqi Exocet missile attack on the USS Stark on May 17, 1987, and marked the single greatest loss of life by the U.S. Intelligence Community.
SIGINT Proves USS Liberty's Northward Heading


K. J. Halliwell (June 3, 2007 -- Revised February 5, 2008)

During the IDF (Israel Defense Force) attack on USS Liberty, a pair of IAF (Israel Air Force) helicopters were dispatched to fly to the attack site. Radio communications between ground-control and the helicopters' pilots were intercepted and tape-recorded by an American military SIGINT (signal Intelligence) aircraft flying relatively near, but not over the attack site.

Recently, the NSA (National Security Agency) declassified and released translated transcripts of the tape's content. In a nutshell, the transcripts contained little information to clarify the circumstances of the attack; although, they contained information about efforts by the helicopters to identify the ship, and instructions for disposition of any survivors taken on board the helicopters. Beyond this, the transcripts contained mostly navigation information.

When analyzed (see map below), the navigation information revealed that the helicopters were guided precisely, by their air controller located at the RADAR contol center in Hatzor, to the ship's dead-in-the-water location about 9 NM (nautical miles) north of the initial air attack location (shown in red on the map). (Note: in a similar manner, a few hours later, after USS Liberty re-established power and traveled much farther north, Israeli air controllers were able to guide precisely the helicopter carrying US Navy liaison, Commander Castle, from the American Embassy in Israel, to the ship.)



The exact pathway taken by USS Liberty to reach her dead-in-the-water location is not clear; but assuming it was a fairly straight path, a simple computation of the average speed required to travel 9 nautical miles in 35 minutes (the time from initial air attack until torpedo hit and stopped her) is 15 knots. Of course, the ship likely traveled (coasted) a bit beyond the point where the torpedo hit; thus, her average speed, during the 35 minute span, may have been a few knots less than 15 knots -- perhaps 13 knots. But if the ship did not travel a straight path, as suggested by photographs taken during the attack, then the average speed was greater than 13 knots. Whatever the ship's actual average speed, it is clear that she traveled northward much faster than her 5 knot speed during her westward trek, before the attack.*

With USS Liberty heading north, at a relatively high speed, the approaching MTBs (motor torpedo boats) would have had to chase her as she rapidly headed farther out toward the open sea, away from the northern Sinai coast. The Liberty's increased speed (higher than El Quseir could have achieved) would have swept away and diffused smoke from fires being extinguished on her superstructure. This, in turn, would have made much of the ship's superstructure, and all of her central mast and forward-half visible (as shown in photographs taken during the attack), and it would have extended the American flag hoisted high on Liberty's large and high central mast -- a feature not present on El Quseir.

In short, the above scenario does not support the IDF's claim that Liberty was mistaken for the much smaller and differently configured El Quseir, due to dark smoke covering her identifying features and no American flag observed flying on her central mast. As Liberty rapidly headed north, being chased by the MTBs, it should have been clear to the MTB captains that she was not "escaping" toward Egypt, or attempting to mount an offensive action against them.