The departure was ASQ4100 (ExpressJet, callsign ‘Acey’); arrival was UAL1243 (callsign ‘United’). NTSB’s preliminary report, released on 5/15/2014, says the two flights passed at approximately 160 feet lateral and 400 feet vertical separation.
Here’s the scenario: with strong northwest winds and one of the parallel runways closed at Newark, FAA’s tower set up departures northbound off Runway 4R and arrivals westbound onto Runway 29. TRACON was using the Bridge Visual Approach to sequence arrivals inbound from southeast of the airport. That routing has the flights crossing the Bayonne Bridge at a fix named LAWNE, and the chart instructs all flights to proceed “…to the west end of the Bayonne Golf Course (then) turn left and proceed to cross CHUMR (the NJ Turnpike Bridge) at 500 feet.”
At the time, winds were exceptionally strong, at 20-25 knots. This tends to mess up timing for the controller trying to launch Runway 4R departures through holes in the Runway 29 arrival sequence. On top of that, arriving pilots tend to bend the rules on the Bridge Visual Approach; they turn left early and thus compress onto the previous arrival. With enough arrival compression, the hole is no longer wide enough to time a departure … but the tower controller may not accurately judge this problem, especially in strong wind conditions.
And so, the near midair happened when ATC launched a departure (green arrow) in front of an arrival (red arrow). ATC audio recordings indicate the conflict was identified at the last second, causing the departure to tip the nose down and stay under the arrival, which was proceeding to abort their cleared landing. Thanks to online aviation websites, the details of this near midair collision are accessible to passengers and the general public.
Fundamentally, the problem that leads to near-collisions like this is the over-scheduling at super-Hub airports like KEWR. FAA proves yet again they lack the will to apply their supreme authority to run a safe system. They let airlines like UAL-COA schedule way beyond the practical safe limits, then just shove it upon the controllers to deal with it and keep it flowing, when runway projects force a normal parallel runway operation to become a dicey crossing-runway operation. All it takes is for the controller to fail to see one arrival while timing the departure, as happened here. This is a systemic problem within an agency that horribly misapplies its abundant resources. FAA places too much effort into shutting down low altitude UAV’s, beating up its few remaining Whistleblowers, PR’ing the facts to hide their many failures and coddling congressional animals (to enable their perpetual reelections). More often than not, FAA’s efforts toward safety are just for show.