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Commercial jet collides with Black Hawk helicopter near Reagan airport

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Re: Commercial jet collides with Black Hawk helicopter near Reagan airport

#301

Post by feistypharit »

DonHopkins wrote: post #120
stouset wrote: post #86

Earlier quoted context omitted.

Trains run on fixed tracks with fixed intersections, and one track might see a handful of them per day. Planes around airports come in from all directions in three dimensions, and there can be hundreds of arrivals per hour. These are vastly different scales of problem domain.

Four Dimensional Navigation, actually! X, Y, Z, plus Time. By incorporating strict time constraints, air traffic controllers can schedule and merge arriving aircraft more precisely, reducing holding patterns and optimizing fuel usage. https://ntrs.nasa.gov/api/citations/19750022064/downloads/19... >4D AREA NAVIGATION SYSTEM DESCRIPTION AND FLIGHT TEST RESULTS >A 4D area navigation system was designed to guide aircraf…

Yes, this multiplies the complexity. When you talk to ATC you always need your tail number and airplane model. Why? Because a landing Cessna 150 is moving at 70mph. An incoming jet is moving at 130mph. And the jet can’t just slow down to 70 or it will fall out of the sky. They need to consider aircraft performance in all aspects of planning.

Re: Commercial jet collides with Black Hawk helicopter near Reagan airport

#302

Post by Ntrails »

femto wrote: post #213
ty6853 wrote: post #181

Earlier quoted context omitted.

[flagged]

The Westminster tradition is for the public service to give "frank and fearless advice" [1] in the interests of the nation. It's still democratic, as a minister can choose to ignore this advice, at their own peril, and issue orders. As hinted at by their name, a public servant's first loyalty should to the public/nation rather than their Minister/Master. Maybe the US has a different system? Of course the above is the…

> It's still democratic, as a minister can choose to ignore this advice, at their own peril, and issue orders

Whilst this is true, the civil service has been alleged to leak/ brief against such orders, not to mention be obstructive about their implementation.

The hard part for me at least is telling whether this is because eg "ordering us to make buildings out of compacted sand is hard" or "we are going to drag our feet as much as we can because this is dumb"

Re: Commercial jet collides with Black Hawk helicopter near Reagan airport

#304

Post by m2fkxy »

whataguy wrote: post #278
user_7832 wrote: post #245

It’s probably really early to ask, but in case anyone here is knowledgeable and has any idea: why didn’t TCAS help avoid the accident? Isn’t it designed for such situations where 2 aircrafts collide? Do military crafts not have it or something?

It’s likely both the helicopter and the jet received a TCAS warning. In dense airspaces, those alerts tend to trigger frequently, so there’s a strong chance they may have dismissed it. The CRJ crew might have been aware of the Blackhawk’s presence, but if the other crew had visual contact with the approaching traffic (the CRJ), they might not have felt the need to take further action.

TCAS RAs are inhibited at low altitude.

Re: Commercial jet collides with Black Hawk helicopter near Reagan airport

#306

Post by htgb »

unsnap_biceps wrote: post #287
toomuchtodo wrote: post #3

https://en.wikipedia.org/wiki/2025_Potomac_River_mid-air_col... https://www.bloomberg.com/news/articles/2025-01-30/washingto... | https://archive.today/n1ark https://www.cnn.com/us/live-news/plane-crash-dca-potomac-was... (CNN live updates) https://old.reddit.com/r/flying/comments/1idbkyd/crash_at_dc... https://old.reddit.com/r/aviation/comments/1idba8i/plane_cra... https://x.com/aletweetsnews/status/1884789306645983…

https://archives.broadcastify.com/44114/20250129/20250129200... contains the ATC feed in addition to the PAT-25 (helo) radio. ~5:41 mark 5342 is given instructions for circling to 33. ~6:45 mark PAT-25 reports Memorial ~7:06 mark tower gives PAT-25 traffic advisory about 5342 and PAT-25 reports traffic in sight and requests visual separation ~8:12 mark tower asks PAT-25 if they have the CRJ in sight. PAT-25 again rep…

I'm impressed by your, and their, hearing comprehension here! Granted, English isn't my native language but even with concentration I struggle to hear what they say.

Re: Commercial jet collides with Black Hawk helicopter near Reagan airport

#307

Post by jonstewart »

rob74 wrote: post #256
jonstewart wrote: post #191

Earlier quoted context omitted.

DCA is great to fly in and out of (I live in DC proper), as it's close, isn't hard to get to, and has a Metro (our subway) station right in front of the terminal, and the airport is fairly easy to navigate once you're in. Dulles now has a Metro station, but it's still far away from the terminal and it's hard to navigate, with gates very far away from the terminal; other than the Saarinen architecture, everything else…

> more funding/staffing for ATC More funding? From an administration that is currently doing its best to get rid of as many federal employees as possible and has an extra "department" (led by you-know-who) dedicated to that? What they will probably do with ATC is privatize it (which is actually a reasonable thing to do - it's private in most of Europe, but if the intention behind it is to save money, it will probably…

I would not be surprised if ATC _at DCA_ gets some more funding given the complicated air traffic environment and its unique position as Congress’s second-favorite airport.

Re: Commercial jet collides with Black Hawk helicopter near Reagan airport

#308

Post by OtherShrezzing »

teractiveodular wrote: post #240

To put this in perspective, this is the first fatal crash of a US commercial airliner in 16 years (Colgan Air Flight 3407 on February 12, 2009) and the first fatal commercial airliner crash in the United States in 12 years (since Asiana Airlines Flight 214 on July 6, 2013). We like to throw shade at Boeing, the FAA etc, but this is still an incredible accomplishment, especially given the explosive growth of traffic o…

I think Boeing specifically attracts criticism due to all the fatalities outside of the US in that time period.

Re: Commercial jet collides with Black Hawk helicopter near Reagan airport

#309

Post by Animats »

hluska wrote: post #263
Animats wrote: post #246

Earlier quoted context omitted.

Right. Helicopter was on Helicopter Route 4, per the map, apparently on course. Aircraft was on approach to Runway 33, apparently on course. That helicopter route crosses the approach to runway 33. That's controlled airspace. How did they both have clearance to be there? We'll know more tomorrow as all the audio and radar recordings are examined.

This comment was written by a US Coast Guard helicopter pilot. It gives a lot of information on how the two aircraft should have been able to share the space and some speculation on what went wrong: https://www.reddit.com/r/aviation/comments/1idba8i/comment/m...

That makes sense.

A helicopter instructor suggests that possibly the helicopter pilots, who were told to go behind an aircraft that was landing, were looking at the previous aircraft that was landing.[1] That's just speculation at this point.

[1] https://philip.greenspun.com/blog/2025/01/29/reagan-national...

Re: Commercial jet collides with Black Hawk helicopter near Reagan airport

#310

Post by throw0101d »

femto wrote: post #213
ty6853 wrote: post #181

Earlier quoted context omitted.

[flagged]

The Westminster tradition is for the public service to give "frank and fearless advice" [1] in the interests of the nation. It's still democratic, as a minister can choose to ignore this advice, at their own peril, and issue orders. As hinted at by their name, a public servant's first loyalty should to the public/nation rather than their Minister/Master. Maybe the US has a different system? Of course the above is the…

> As hinted at by their name, a public servant's first loyalty should to the public/nation rather than their Minister/Master. Maybe the US has a different system?

Both systems rely on the people in charge being told okay with being told "no, this is a bad idea".

The Ministers/Secretaries/Executive may think their plan(s) are a good idea and the civil service are being obstructionist.

(Of course the civil service could be wrong as well.)

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