Where did Converging Runway Operations (CRO) come from? Where are we at today? What can we do to improve the Arrival Departure Window (ADW)? This will need to be in a summary that will be briefed to executives, must be brief, to the point, and keep their attention. I’m putting down 5 references, but this number is up to youThis link is to the NTSB’s request to the FAA to take action on their Safety Recommendations for CRO due to numerous NMAC occurrences (July 2013). The main takeaway from this is that this document calls for the establishment of Separation Standards for Converging, Nonintersecting Runway Operations. [The NTSB is concerned that existing FAA separation standards and operating procedures are inadequate to prevent such events and need to be revised to ensure safe separation between aircraft.]https://www.ntsb.gov/safety/safety-recs/recletters/A-13-024.pdfThis link contains the pdf file of MITRES Monte Carlo Simulation for Evaluating Airborne Collision Risk in Intersecting Runways.https://www.mitre.org/sites/default/files/publications/13-2900.pdfThis Monte Carlo Study was conducted at the request of the FAA in August of 2013, one month after the NTSB’s safety recommendations were submitted to the FAA. Some of the main takeaway items from this document are:The terminal environment presents an elevated risk of NMAC events: a 2011 study found that 59% of the reported NMAC events over a ten year period occurred in the airport environment.4 As previously mentioned, NMACs are considered hazardous events, for which the SMS requires a TLS of one-in-ten-million (P(event) ≤ 10-7). However, the terminal airspace presents an additional NMAC risk: in airspace above 5,000 feet an Air Traffic Controller (ATCO) can mitigate potential NMAC events by instructing one aircraft to descend and the other aircraft to climb. In the terminal area, however, the close proximity to the ground prevents one of the aircraft from being able to descend, making vertical separation more difficult. The SMS manual provides no explicit TLS for NMACs in the terminal airspace. Consequently, we conservatively apply the TLS of a catastrophic event: one-in-one-billion (P(event) ≤ 10-9).2This is where the (P(event) ≤ 10-9).2 – or one in one billion Target Level of Safety originally came from. As I mentioned before I find it disturbing that after categorizing Converging Runway Operations as catastrophic and assigning a Target Level of safety of one in one billion (highest in the NAS), that we still don’t have mandatory separation requirements. Meaning when the ADW requirement is compromised, controllers are not mandated to take action and send the converging arrival around. They have the option (at MSP at least) to do nothing, which completely eliminates any Target Level of Safety and returns the operation dependent to the original state which produced of dependence on pilot/controller reactions & caused all the problems in the first place.NTSB Safety Recommendations:https://www.ntsb.gov/_layouts/ntsb.recsearch/Recommendation.aspx?Rec=A-13-024https://www.ntsb.gov/about/employment/_layouts/ntsb.recsearch/Recommendation.aspx?Rec=A-00-035One of the many Las Vegas incidents:https://www.flightglobal.com/news/articles/ntsb-cites-lack-of-procedures-in-jetblue-a320-and-le-383470/ADWSome of Mitres ADW propagandahttps://www.mitre.org/publications/project-stories/decision-aid-for-controllers-helps-prevent-near-misses
