Summary
On an unspecified date, TWA Flight 388, a DC-9 (registration N924L), was climbing to 7000 feet in clouds when Baltimore (BWI) TRACON advised the crew of a Piper PA-28R aircraft straight ahead at 3 miles, descending from 6700 feet. The incident occurred within the BWI Airport Radar Service Area (ARSA). The Piper was operating under Visual Flight Rules (VFR), while TWA 388 was on an Instrument Flight Rules (IFR) flight plan.
Traffic Alert
As Flight 388 passed through 6000 feet, the captain requested a traffic avoidance vector. The TRACON controller instructed the flight to level at 6000 feet and turn left to a heading of 270 degrees. By that time, Flight 388 had already reached 6400 feet.
Evasive Action
While turning left, the TWA aircraft broke out of cloud tops, and the aircrew saw the Piper PA-28 at their one o'clock position. The TWA crew took evasive action. The captain reported that the Piper passed approximately 500 to 1000 feet laterally, with no vertical separation.
Pilot Accounts
The Piper pilot stated that he saw Flight 388 as it emerged from the cloud top in a left turn. He estimated that Flight 388 passed with approximately 3/4 mile separation.
Communications
Both pilots were in contact with BWI TRACON, but they were on different radio frequencies and were being handled by different controllers. Flight 388 was being handled by a trainee controller.