Intelsat, the international satellite organization, has filed a lawsuit seeking $400 million from rocket builder Martin Marietta Corp. for a launch that left a $145 million satellite in a useless orbit.

The suit, filed in U.S. District Court in Baltimore, accuses Martin Marietta of miswiring its Titan 3 rocket and botching the launch for which Intelsat paid $115 million.

Martin Marietta has said a wiring problem caused failure of the satellite and its booster rocket to separate from the Titan 3 when they reached orbit. As a result, the satellite could not be sent to its duty station 22,300 miles above Earth.

The satellite, which Intelsat had not insured, will be a total loss unless it gets a boost. A space shuttle crew is expected to try to rescue the satellite next year, costing Intelsat another $90 million or so.

Martin Marietta had no immediate comment on the lawsuit, filed Friday.

Martin Marietta attempted a preemptive strike against Intelsat in July, asking the federal court to declare that its only legal responsibility was to provide a replacement launch.

Elliott Miller, Martin Marietta's director of corporate relations, said Intelsat's suit had no merit and that Intelsat had had an opportunity to buy insurance but declined.

"Under the launch services contract between Martin Marietta and Intelsat, the relationship of the parties for risk of loss is clearly set forth," he said yesterday. The contract provides that Martin Marietta is not liable for the satellite failure to achieve orbit."

The Intelsat suit alleges that Martin Marietta miswired the launch vehicle "so that the payload did not and could not separate from the launch vehicle in response to commands sent by the Martin Marietta flight computer and computer software."

In its suit, Martin Marietta said it might have to go out of the commercial launch business if it were made to pay damages. "The very viability of Martin Marietta's commercial launch services business is dependent on a determination of its rights under the contract," it said.

But in its counter-suit, Intelsat noted that Martin Marietta was considering dropping out anyway, having told its stockholders in an annual report that production of Titan 3 rockets "will depend upon the market for heavy-lift launch vehicles."