Three members of the National Symphony Orchestra received left this week informing them that the contracts will not be renewed next season.

Sources identified the player first flutist Wallace Mana, who have been with NSO for 32 years, and George parker and Douglas Stevens of the horn section. Now could be reached for comment early last night.

The action comes six weeks after Mstislav Rostropovich assumed the post of music director, and suggest new development in the orchestra personnel policy. During the seven year tenure of Antal Dorati, Rostropovich's predecessor, only five [WORD ILLEGIBLE] in the NSO changed hands, most of them by attrition.

The notifications, signed by Managing Director Oleg Lobanov, [WORD ILLEGIBLE] this week because of a contact prevision that musicians be informed within the first six weeks of a National Symphony season if they are not to be rehired. Contracts are for one year, and the orchestra players have the right of appeal on such section.

Appeals would go to a board contracting of 13 of the musicians colleague. It would be elected by the players and be divided between first chair mus icians and other players. The appeals board has final authority and could overruled Rostropovich.

Rostropovich was en route to Europe and could not be reached for comment. It is known that last Wednesday he started auditioning applicants for possible vacancies.

Robert Noerr, manager of the NSO, said that because of the exceptioned nature of the actions the National Symphony board will be asked to consider certain measures to alloviate the impact of the decision upon the personal lives of the players.