Twenty-seven air traffic controllers have sued the Civil Service Commission in an attempt to win higher job classifications and pay schedules.

The suit, filed in U.S. District Court here, grows from a settlement that the controllers union - The Professional Air Traffic Controllers Organization - reached with the commission and the Federal Aviation Administration last year.

An air-traffic slowdown had preceded the agreement. The FAA operates the air traffic system and hires the controllers, but the commission controls the job classifications.

What the union won during its negotations was a job classification schedule that gave higher-paying GS-14 slots to controllers working in areas with heavy airplane traffic, GS-14 slots were awarded to centers controlling en route airplanes near Chicago, Cleveland and New York.

Lower-paying GS-12 and GS-13 slots were assigned to other en route centers, including the one at nearby Leesburg.

The controllers filing the suit, who work in Albuquerque, Salt Lake City, Seattle, Denver, San Francisco, Anchorage, Honolulu, Miami and Kansas City, said they did the same work as those in Chicago or New York and should get the same job classification.

Robert Poli, executive vice president of PATCO, said the new classifications had been explained to controllers across the country but that "It's very difficult with the profession we're in to equalize" all the pay structures.

PATCO officials told reporters privately at the time of the settlement last November that the new classification was he best they could get. PATCO will not intervene in the suit, Poli said.

The Civil Service Commission had no comment.