The leaks are just part of a poorly handled investigation which has soured US relations with Egypt. And they have contributed to the idea that there is only one possible theory of how flight 990 came to crash; in fact there are still several lines of inquiry.
Several US agencies and newspapers on Friday quoted an anonymous "law enforcement official" who retracted an earlier claim that the relief co- pilot, Gameel el-Batouty, had said: "I have made my decision now," before reciting a Muslim prayer. The official claimed that this was "an innocent mistake", but it was one of the principal elements which led the US media to assume that Mr el-Batouty had put the aircraft into a dive in an attempt to commit suicide. Yesterday, the pilot's family - and most of Egypt, which is aghast at the suggestion that the jet was deliberately downed - was celebrating an important victory.
The only law enforcement agency directly involved in the probe is the FBI. The agency is thought to have been the source of numerous other leaks which led Jim Hall, head of the US National Transportation Safety Board, to condemn a "cyclone of speculation" last week.
The initial leap to judgment was made after it was revealed that someone, perhaps Mr el-Batouty, had uttered a prayer shortly before the aircraft went into a precipitous dive. No attempt was made to explain that Muslims can use this prayer in everyday circumstances and that it does not necessarily indicate either religious zeal or an abandonment of hope for life. It can be used before beginning to cook a meal, for instance.
US authorities were hampered by the fact that their translators were not Egyptian Muslims. They were, according to some sources, Lebanese Christians from the Central Intelligence Agency who would have had little idea of the meaning of the sentence.
One US Congressman has booked himself on to an EgyptAir flight to Cairo to protest at the torrent of speculation. Jack Metcalf, a Republican from Washington state, said he would switch to EgyptAir for a flight from New York to Cairo for meetings with Egyptian officials as a protest at the "premature and irresponsible spec- ulation". "There are family members who are needlessly being anguished by these stories that are being splashed across newspaper headlines," he said. Boeing aircraft are built in his district and the dispute has damaged the image of Boeing in the Middle East. Some Arab diplomats see the mishandling of the dispute as a deliberate effort by US officials and Boeing to divert attention from any mechanical failings.
At least one alternative theory of how the crash might have occurred is being mulled by officials. The Seattle Times reports that the EgyptAir crew might have accidentally cut off the fuel to the aircraft's engines.
A "runaway stabiliser" is a relatively common malfunction on an aircraft, when the horizontal control surface moves on its own. The emergency procedure calls for the crew to shut down hydraulic pressure, moving two switches from "normal" to "cut out". The stabiliser trim switches are located alongside another pair that control fuel being pumped into the engines. "At least twice before, veteran pilots have cut off fuel to both engines while reaching for a nearby switch," said the Seattle Times.
The investigation of TWA Flight 800, which crashed off the US coast in 1996, revealed a bitter struggle between the NTSB and the FBI for control. The New York office of the FBI was so convinced there was a bomb or missile that it elbowed the safety experts aside. It mishandled evidence, withheld information and interfered with the probe. Within six weeks the investigators decided that a mechanical failure was the most likely cause, but the FBI blocked the release of the report, and it was over a year before that conclusion was reached publicly.
The recriminations over the latest disaster have also revived memories of the fiasco of the early stages of the Oklahoma City bombing in 1995, when Islamic militants were immediately, and wrongly, blamed. In this case there are too many possible causes - from a bomb to the suggestion that another pilot had been allowed a turn at the controls (there were 33 Egyptian military men on the flight, including a number of F-15 pilots) - to make the swift indictment against one pilot stick.
The NTSB is still not sufficiently convinced that the crash was a deliberate act to hand the case to the FBI. All this, however, is little consolation to Mr el-Batouty's family as they struggle to save the dead pilot's reputation.