The June 12 editorial on airline service and other issues arrived at the right conclusions, but along the way it went off-track on some points.

To say the Department of Transportation argued "for years that it had enough trained controllers" and then suddenly reversed itself is simply wrong. On two occasions in the past 21 months, Secretary Elizabeth Dole approved the Federal Aviation Administration's requests to add a total of 1,225 controllers to the work force, and most of them are already on board. Her recent approval of the FAA's request to hire 955 more controllers, supervisors and traffic management coordinators was not a sudden reversal. Rather, it was the third time in less than two years that such increases have been requested, approved and announced.

Secretary Dole has repeatedly said that if more controllers were needed, she would act immediately to increase the work force. A recently completed review by the FAA predicted air traffic would grow 5 to 6 percent in 1988, rather than 3 to 4 percent, as previously projected. The DOT's new request, based on that review, addresses needs for next year and thereafter.

I would like to make one other point: FAA is well ahead of its original goal of having a controller work force (experienced controllers, controller trainees and air traffic assistants) of 15,000 by Sept. 30. The controller work force reached 15,115 by the end of May, and FAA expects it to reach 15,225 by Sept. 30 -- almost one year ahead of schedule.

JIM BURNLEY Deputy Secretary of Transportation Washington