USAir said yesterday it plans to remain in Northern Virginia, ending speculation about where the company might locate its consolidated headquarters after its mergers with Pacific Southwest Airlines and Piedmont Aviation.

Virginia Gov. Gerald L. Baliles and USAir's chairman and president, Edwin I. Colodny, jointly announced the decision, noting that a specific location has not yet been chosen.

Since USAir's announcement last year that it would merge with PSA, a San Diego-based carrier, and its subsequent decision to acquire Piedmont, which is headquartered in Winston-Salem, N.C., rumors have circulated that USAir was considering a major move.

Officials from San Diego, Winston-Salem and Maryland tried to attract USAir, extolling the benefits of locating a new, consolidated headquarters in their jurisdictions, said David Shipley, a spokesman for USAir.

The airline's headquarters now are located in hangars 11 and 12 at Washington National Airport, in an office building nearby in Crystal City and in Fairfax County, where it has a management information services office. That office will remain where it is, although about 50 jobs are being shifted to North Carolina.

Shipley said he believed the airline would choose a site near National Airport for its consolidated headquarters.

The company said yesterday it will consolidate revenue accounting functions for the merged airlines in Winston-Salem. The first phase of that consolidation will occur in April, when PSA is merged into USAir. About 120 jobs, mostly from USAir, will be moved to North Carolina at that point.

In early 1989, when the merger with Piedmont is expected to be completed, another approximately 150 jobs will be transferred from Washington to Winston-Salem.

The company said it expects that most of the Washington-based employees who elect not to transfer will find other jobs with USAir here.