TWA <TWA> IN COURT SETTLEMENT WITH USAIR <U> Trans World Airlines Inc said it reached an agreement yesterday in federal court with USAir Group Inc that prevents TWA from buying additional shares of USAir. Under the agreement, TWA, which holds about 15 pct of USAir stock, will not buy more USAir shares before April 23 and will not do so after that date without giving 14 days notice to USAir. TWA also agreed that it would not knowingly and willingly interfere with the consummation of the merger between USAir and Piedmont Aviation Inc <PIE>. TWA said the court agreement confirms previous announcements by the company, in filings with the Securities and Exchange Commission, that it does not presently intend to seek control of USAir or to acquire additional common stock. As a result of the agreement, the court removed a previous temporary restraining order against TWA, the company said. TWA and USAir have also agreed that all litigation between them in Pittsburgh and Delaware will be stayed until April 23. TWA said the agreement does not prevent it from commenting to regulatory agencies on the USAir, Piedmont merger. In a separate statement, USAir said the agreement also included a provision that all USAir shares currently owned by TWA and its chairman, Carl Icahn, will be voted through a voting trust in proportion to the votes of other shares not controlled by TWA or Icahn.