Six white former D.C. Fire Department battalion chiefs filed suit against the city yesterday in U.S. District Court, claiming they were racially discriminated against when they were passed over for promotion to deputy fire chief.

The suit demands back pay and pension adjustments for the former firefighters, all now retired from the force.

The six allege they were passed over in late 1979 and in early 1980, when a total of three black firefighters were promoted from battalion chief to deputy chief, according to Edward F. Dougherty, a spokesman for the group. At that time, he said, there were 33 battalion chiefs in the department and the top 19 in seniority were white. One of the black firefighters promoted was Norman Richardson, who became deputy chief in 1979 and subsequently was named fire chief.

Richardson resigned his post in March.

The suit marks another step in a longstanding and bitter dispute over promotion practices in the fire department, in which blacks have argued they are underrepresented in the department's top ranks and whites have complained they are denied promotions in favor of blacks who are less qualified.

City administrator Elijah Rodgers declined to comment on the suit yesterday.