thomas

I ran a search for airborne conflicts and near mid-air collisions at Ronald Reagan Washington National Airport (DCA) for the last five years in NASA's Aviation Safety Reporting System (ASRS), and found six of them (~1.5 per year if we exclude the 2020–2021 period of virtually no traffic due to COVID–19). 🧵

Aviator, diver, Etherean, nexialist, PhD in aviation ∩ climate science | Host of /diving /ethfinance /eth-staker /geopolitics /science /singapore /thomas

#2 is ACN 1871698 in Jan 2022. ATC failed to separate a landing aircraft and a crossing helicopter above the Potomac, resulting in a resolution advisory followed by a GPWS alert. An evasive maneuver had to be performed.

#3 is 1935869 in Sep 2022. ATC reported an airborne conflict between two military helicopters and cited manpower shortage as causal (controller working two positions).

#4 is 1947048 in Oct 2022. A landing aircraft received a traffic followed by a resolution advisory over the Potomac and performed an emergency climb to avoid collision with a helicopter lifting off.

#5 is 2067857 in Dec 2023. A landing aircraft came within 20–50 ft of a drone. Approach continued as normal after that.

#6 is 2106384 in Apr 2024. A landing aircraft received a traffic advisory as it passed 300 ft above a crossing helicopter not properly deconflicted by ATC. The aircraft briefly departed from the glide path but eventually resumed its approach and landed normally.

In hindsight, four of these were consistent warning signs. I fully expect visual separation rules to change at least at DCA, if not nation-wide after the FAA completes its investigation into yesterday's accident.

Link to the database: https://asrs.arc.nasa.gov/search/database.html 🎬

#1 is ACN 1618051 in Feb 2019. A Bombardier CRJ200 did a go-around due to a wind gust and found itself climbing too close to a departing Embraer ERJ170. A resolution advisory was issued by the TCAS and an evasive maneuver had to be performed.

Thanks for this!

Reading now

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Horticulturalist. Environmental hand wringer. Open source enthusiast. 

mfer #9187

This is the important question, really.

I checked LGA for comparison — as it is also a coastal airport on the Eastern Seaboard, very congested, and with rotary wing traffic mixed in. There were multiple reports over the same period, mostly involving drones (which ATC can't do anything about); and only one involving a helicopter (ACN 1682814).

This one was also a near-miss between a landing Embraer ERJ 190 and a crossing helicopter, leading the pilot to write: "It would be good to know at what point LGA controllers should no longer issue a crossing clearance with an aircraft on final to Runway 22".

To me, rotary-wing aircraft are the sky equivalent of mopeds on car-congested roads: they fly at speeds and trajectories (incl. vertical) that are so different from those of fixed-wing aircraft, that it's always challenging to separate them, especially visually (as is very often the case for low-altitude helicopter flights that operate VFR).

Is this an abnormal amount of near misses for a major metro airport?

If not is there something about the design of this one that makes it more prone to collisions and near misses?

This podcast came out a week ago

https://youtu.be/l5GGUY0d6CU?si=KGOMp-e25FjX8yym

Thanks for the research, interesting!

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