Though it's still unclear what caused the crash of EgyptAir Flight 990, lawyers who specialize in suing airlines are already studying potential litigation and, in at least one instance, conferring with the families of victims.

"It's a good case," Lee Kreindler, a New York attorney and veteran aviation disaster trial lawyer, said yesterday. "We met with two families today and we're meeting with two more tomorrow."

A call to a public relations spokesman for EgyptAir was not returned yesterday. Desmond Barry, an attorney for the airline, said, "I'm sure you're going to see litigation, but I don't think we know enough facts to know what the airline will do. We don't even know what happened yet."

Establishing EgyptAir's legal liability in any possible suits will be relatively easy, experts said, even if it turns out that the plane crashed because of a criminal or suicidal act by one of the pilots. Under international treaties, airlines can dodge liability only if they prove that they took "all necessary measures" to prevent the damage--a legal hurdle that is virtually impossible to clear. If some mechanical failure is ultimately found to be to blame, relatives could also sue Boeing or any outside maintenance company that tended to the plane. But regardless of what caused the accident, lawyers can argue that the airline could have done more to prevent it.

The inevitable EgyptAir lawsuits won't necessarily yield a jackpot, however. That's because a 79-year-old law, the Death on the High Seas Act, would severely restrict awards to the families of victims. The law, originally designed with the widows of seamen in mind, allows the relatives of those killed in international waters to recover only a portion of the future earnings of decedents. The law effectively blocks the often astronomical pain-and-suffering awards. Congress is considering an overhaul of the Death on the High Seas Act that could loosen restrictions; the matter is now in conference.

Plaintiffs' lawyers face another problem. Under the Warsaw Convention, the relatives of airline crash victims are allowed to sue in just four venues: the country where they purchased the ticket, the country of their final destination, the country where the carrier was incorporated or the carrier's principal place of business. EgyptAir is incorporated, based and conducts its principal business from Cairo.

Anyone who purchased a ticket for Flight 990 in the United States would be allowed to sue in this country, but passengers who bought their ticket in Egypt would have to sue there, where liability laws are far less friendly to plaintiffs.

These pitfalls aside, Kreindler says he and others are eager to file suit. "The lawyers who defended the airline in the Swissair crash [of last year] also represent EgyptAir," Kreindler said. "And I called them this morning to say, 'We'll be doing business again.' "