Incident Overview
At 1710:53 Eastern Standard Time, the local control tower controller (LC) at Newark International Airport cleared Continental Flight 321, a DC-9-82 (registration N806NY), for takeoff on Runway 22L. Eleven seconds later, Continental Flight 688, a Boeing 727 (registration N577PE), reported 'left downwind for Runway 29.' The LC instructed Flight 688 to 'maintain 1500 as you cross over the field.'
Runway 22L, which was 9,300 feet long, was located south of Runway 29. As a result, the left downwind leg for Runway 29 was near the departure end of Runway 22L.
Sequence of Events
At 1712:12, the LC told Flight 321 that Flight 688 was passing 'overhead & behind you at 1800.' Around that time, the crew of Flight 321, climbing through 1,000 feet, observed Flight 688 passing directly overhead. The captain of Flight 688 saw Flight 321 taking off and estimated the separation remained in excess of 1,000 feet. However, the captain of Flight 321 was concerned about the close proximity and called the tower after landing.
Radar data showed that the aircraft passed with approximately 400 feet of vertical separation and 1,000 feet of lateral separation, roughly one-quarter mile south of the airport. Both flights were operating under Instrument Flight Rules (IFR) flight plans. The LC did not advise either flight crew of the traffic until 1712:12, moments before their flight paths crossed. The airport was experiencing heavy traffic at the time.