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What the Black Hawk pilots could see, just before the crash (nytimes.com)
38 points by bookofjoe 4 months ago | hide | past | favorite | 65 comments




Be warned: The article does not show what the pilots could see.


Yes it does? It shows how the other aircraft in the sky would have appeared from their position


It needs a lot of enhancements to be useful. Firstly it should be a real time video like the simulations in the movie about Capt Sully's water landing in the Hudson. The aircraft lights need to be modeled accurately as well as views both with and without night vision equipment.


Doesn't matter what they could and could not see - the ceiling for helicopters there is 200 feet. They were flying at 300. Make whatever conclusions you like from that, I've made mine.


Excerpts from the article:

"(According to investigators, this altitude data was rounded to the nearest 100.)"

[...]

"At over 100 miles an hour, the helicopter could have risen to 300 feet from 200 in seconds, because of winds or other factors. Such anomalies are not unusual and can be quickly corrected."

I read your comment as implying that you've concluded it's pilot error. I don't disagree, but a good system should be robust against human error. Perhaps the permitted flight paths were too close together? I'm not an expert, but a commercial jet making a landing approach 100 feet above a helicopter doesn't seem safe or normal to me.


100ft isn't anywhere near an acceptable margin. The helicopter may bear the immediate blame due to going above the altitude limit, but ultimately the design of this corridor was completely nuts.

This seems like a classic normalization of deviance. Reportedly there were literally a hundred automated collision warnings between airliners and helicopters in this area over the past decade. One such warning should raise eyebrows. Two should start people thinking there's a systemic problem. More than a handful should prompt an investigation to resolve the root cause of the conflicts. Instead, they (at least the system as a whole) seem to have decided that they weren't a real problem because nothing had happened yet.


In other situations the normal vertical separation is 1000ft. In this situation ATC was depending on the visual conditions for the pilots to "see and avoid", but it's especially nuts if you factor in wind shear and wake turbulence that can change an altitude by 100ft in seconds.


I wonder whether telling either the army to use cars, or that the airport should be moved further away from the city was doable for atc personnel, or even their higher ups.


You wouldn't need anything so extreme. Just prohibiting landings on runway 33 simultaneous with helicopter traffic underneath the approach path would have done wonders here. Additionally, require military traffic to have ADS-B, and ensure that the tower is sufficiently staffed to have the dedicated helicopter controller that it's supposed to have.


Just prohibiting landings on runway 33 simultaneous with helicopter traffic underneath the approach path .. Additionally, require military traffic to have ADS-B

I'm thinking you're not quite understanding the nature of the missions many of these helos undertake.

I personally don't think the practice should be allowed, but that's why we need to have a discussion. We need to determine how necessary are these practices?

That said, I can guarantee you that the ideas you put forth would be rejected by government and military planners. Those ideas would defeat the entire point of some missions. What we can do is talk about whether or not DCA is a facility that should be open? Things of that nature.

But any ideas that result in tipping off the mission will be non-starters for the guys and gals seated on the military/intelligence side of the table.


I don't understand what you mean. What is it about these flights that would make it impossible to prohibit them from flying under the 33 approach while it's in use, or prohibit incoming traffic from landing on 33 while these flights are nearby? Why can't they use ADS-B?


One of the missions of those helicopters was the immediate evacuation of personnel in the event of attack against Washington D.C. That requires the speed and range that a helicopter can provide but cars can't. To do that mission requires training and practice flying through the area, because as everyone in the military knows, you fight like you train, and so they need to be flying through DC regularly, both day and night.

As for DCA itself, yeah, there have been people trying to close it for decades- that was originally the plan once they opened IAD in 1962. But DCA was so close and so convenient to the city and IAD (and later BWI) are so far away that no one has really wanted to pull the trigger on closing it, even as the airspace got more and more complex after the September 11th terrorist attacks.


NTSB did release some follow up data. They have the bottom of the jet at 325', +/- 25'. Helicopters add a tough element to any airport operation and DIA is one of the more challenging airports with the extra restrictions on routing.

(Never flown into that one as not an ATP. I'd never be able to get closer than College Park. Even that was a non-trivial exercise in paperwork.)


What's complicated about it? Don't get within a mile. Some 250g drone can't, why should this thing?


why should this thing?

'Cuz "National Security".

End of discussion.

/s

You may laugh, but that's historically the argument in support of these practices. No one wants to go on record as questioning the practice. Maybe they will finally do something now? But it wouldn't surprise me if they don't.


DCA, not DIA. DIA is in Denver.


> Perhaps the permitted flight paths were too close together?

My understanding is that the helicopter was military and didn't need to submit a flight plan. They get to fly where ever they want


There is a difference between not needing to submit a flight plan, and flying wherever they want. They absolutely have rules to follow about where they fly.


> They get to fly where ever they want

Reminds me of the story of the Navy ship and lighthouse: https://en.wikipedia.org/wiki/Lighthouse_and_naval_vessel_ur...


A flight plan doesn't have much to do with permission to fly somewhere. It's more about ATC not being surprised if an aircraft shows up in a given airspace, and search & rescue noticing if an aircraft doesn't show up at its planned destination.

All aircraft have separation and avoidance rules that apply at all times.


> They get to fly where ever they want

In controlled airspace aircraft fly where they are told to fly by controllers:

* https://en.wikipedia.org/wiki/Controlled_airspace


Well, except for VIP helos. Basically certain military and government aircraft can do things other pilots can't.

I can guarantee you, if I were flying the helo, the transcript between myself and ATC would be significantly different. When you're certain military and government pilots, it's basically, "Um, sir, I don't mean to disturb you, but are you certain you have visual?".

The real issue is allowing certain military and government aircraft to essentially do whatever they like. I understand the whole "National Security" thing, but, I mean, maybe we can at least talk about the practice? It's not a practice that seems unsafe. It's a practice that is unsafe.


I highly doubt this. US Air Force fighters intercepting an unknown aircraft near the Whitehouse still request ATC clearance so they don't accidentally run into an airliner. And we're talking something that shoots missiles into other planes. Any VIP transport isn't going to get any higher priority.

Here's why: https://en.wikipedia.org/wiki/Hughes_Airwest_Flight_706

And they don't need priority. If Air Force One wants to land anywhere, they simply have the airport closed and the airspace cleared. And you don't need to close an entire airport. You can just mark off a place in the sky that's restricted during a certain time.

Additionally, any plane can declare an emergency and take priority over all other traffic, including anything military, including Air Force One. It would be silly if you think you are so important that an airplane currently in the middle of crashing will go around you.

You can verify all of this by listening to ATC transcripts on YouTube. They are pretty easy to find if you're looking for sources.


You're misinformed.

"US Air Force fighters intercepting an unknown aircraft near the Whitehouse" don't request anything from anyone outside their chain of command. That's not how anyone gets orders sir.

NMCC is in charge, and any idea you have to the contrary is yours alone.

Now, will NMCC, or someone in the chain, communicate with ATC as part of the response? Yes. But only for the purposes of keeping ATC apprised of the situation and informing ATC that fighters are in the area. No one is standing around waiting on the results of clearance requests in these scenarios.

Your assertions would not only be bad policy, but they're contrary to military sense.

My idea is to sit down and have the conversation about why certain helos are engaged in some of these dangerous practices? And if that reasoning be sufficiently compelling, to consider the pros and cons of closing DCA. If the reasoning be not compelling, then we need to have another discussion about different operating protocols for these aircraft.


The fighters talk directly to ATC to request to a block of airspace to fly in so they don't run into anything and ATC keeps it clear. This is a regular occurrence in the DC area. This also happens with civilian aircraft like medevac helicopters. They obviously need priority but you also need to route them around stuff you can't move out of the way in time.

You may not strictly need the clearance but it's a really good idea to know where it's safe to fly.

> My idea is to sit down and have the conversation about why certain helos are engaged in some of these dangerous practices?

This isn't different from planes colliding on a runway. There are bad procedures. The NTSB will investigate and make recommendations. The military will offer their opinions. And the FAA will ignore everything until it happens a couple more times. Or with see and avoid, bury their heads in the sand and hope the problem goes away.


And except for planes that don't or can't follow rules or instructions. For example: https://en.wikipedia.org/wiki/2006_New_York_City_Cirrus_SR20...


I'm sure in a national defense scenario they have ways to "pull rank" and do what they need to do. But this would require a good reason. Like a VIP was on board and someone was attacking them.


It's very easy to pull rank. When Air Force One flies into an airport they have the airport and airspace closed.

There's also no need to because current procedures already covers this. All the aircraft would have to do is declare an emergency and they get to go and land wherever they want.


In that scenario civilian aircraft are all grounded.


This is the thing people don't understand. Certain military and government aircraft can pull this kind of crap even when it doesn't seem necessary. (At least not to me as an outsider).

Now it's easy to say, "Well, Bilbo0s, who are you to say it wasn't necessary?"

That's true, but it's an argument that's closed onto itself. We can't probe any further 'cuz "National Security". So this unimaginably dangerous practice of allowing military and government pilots to do this sort of thing "if necessary" continues.

We need to, at minimum, have a discussion about why the practice is necessary?


Your understanding is incorrect, this isn't how airspace works.


Anyone flying under visual flight rules does not need to submit a flight plan. If you never enter controlled airspace, you don't have to talk to ATC at all.


We should wait for the official report, but there is speculation the helicopter altimeter was miscalibrated.

Apparently on the old avionics in the helicopter, the altimeter is calibrated by manual entry of barometric pressure to the nearest 0.1 inch Hg. So a rounding error could cause a 100 ft altitude discrepancy.


> Apparently on the old avionics in the helicopter, the altimeter is calibrated by manual entry of barometric pressure to the nearest 0.1 inch Hg.

That's how it's done in all aircraft.


All US aircraft. The rest of the world uses modern units :-)


The thoroughly modern Pascal system from the 1600s?


The metric system.

"The name pascal was adopted for the SI unit newton per square metre (N/m2) by the 14th General Conference on Weights and Measures in 1971"


inHg, hPa, it doesn't change that the input is manual.


Every airplane has that. A fully computerized cockpit will have that. Its a feature.

It has to be manually set because there is no way to know what the reference pressure should be for altitude while you are in the air (the reference isn't necessarily the true sea level pressure since that changes constantly, it is what the SLP was at the time the reference was set). Using a non-pressure altimeter you can normally figure out what true SLP is, but the idea is that you want all planes using the same altimeter readings, even if it is not strictly correct.

All aircraft in a given area are told the reference by the controller when they enter the control area.


Thats the kollsman window and as far as i am concerned is pretty common also in modern avionics?


The main conclusion is flying helicopters this close to a commercial airport approach at night is a bad idea. I'm sure it's much safer, but ever seen the approach into SJC?

https://www.youtube.com/watch?v=bpT1wjwlL3Q&t=254s&e=270


100 ft. of separation is an idiotic safety margin.


The combined height of a blackhawk and a large jet is about 60ft. The combined length is a bit over 300ft, and since neither aircraft is unlikely to be level, some portion of that length gets contributed to their effective height while flying. Just given the size of the aircraft, I wouldn't be surprised if they can potentially overlap even if their altimeters are 100ft apart.


That wasn't the safety margin. That was the altitude discrepancy that was left after the Helo disregarded or misinterpreted ATC directions and flew where they specifically were told to avoid.


If the airplane was on the correct approach at 300 ft. and the Blackhawk was restricted to 200 ft. the margin is 100 ft.


No, The Blackhawk was supposed to be at a different altitude AND a different location.

The loss of separation was not primarily because of the Z axis, but because the Blackhawk was in the wrong spot on the X,Y axis.

The controller said, paraphrasing ATC speak, "Do you see that plane? You are cleared through the airspace as long as you see and avoid that plane by going behind it. You are responsible for separation if you accept this". The BH pilot responded, "I see the plane, I can and will avoid it. It is my responsibility to go behind it, and I will do that."

The collision would have been narrowly avoided if the Blackhawk was at the right altitude, but that was the last in a long line of piloting errors that caused this midair.

If they were at the correct assigned altitudes it still would have been an incident because the loss of separation wasn't about the altitudes, it was about the errors made long before then. They weren't cleared to be where they were, and no controller would allow an altitude only separation of 100ft.

Simply put, that helicopter pilot was specifically not supposed to be where they were, and the standard separation was violated before the altitude became an issue.

If you narrowly miss someone driving down the wrong side of the highway after crossing the medain, the margin of safety isn't the distance that you missed that car by, it is the median.


Yes -- 500 ft is considered inadequate in general.


Original link is unpaywalled


It requires you to sign into an account though.


That's not true: you can read it — with 3D visualizations, which are blacked out in the archive version — without signing in to an account:

https://www.nytimes.com/interactive/2025/02/05/us/dc-crash-h...

Note "unlocked" in URL above.

Try it!


I did try. Still “sign in to read.” Your second link gives me an option to close the full screen modal (or the NYT gives second-try people a pass.)


Worked for me. I got a little popup that I dismissed, then I saw the full article.


How did you construct that link? For example, where do these bits come from: 1.wE4.E3Qm.Fu3gorL0b1_5


I didn't construct that link: It was the link that appeared when, as a New York Times subscriber, I clicked "Share this story."


> Black Hawk helicopters often fly these routes as a pair, doubling the number of eyes scanning the sky for a safe passage. But that night, there was only one. Its two pilots worked together to navigate ...

So how many WERE there?!? Two, as in the first and third sentences, or just one, as in the second sentence?

Who writes this drivel and does not even proofread it??


Two helicopters with two pilots = 8 eyes. One helicopter with two pilots = 4 eyes.


I had no trouble understanding, but perhaps it could be made slightly less ambiguous, like:

> But that night, there was only one helicopter, and its pilot and co-pilot worked together to navigate...


The sentence you highlighted holds the answer.


I think everyone here could be confused, here's my understanding. There were three people in the helicopter that night, two pilots and one crew member. They usually fly with two crew members for a total of 4 people in the helicopter. The two crew members usually sit one on each side of the helicopter, with the task of looking out the windows to enhance situational awareness.

The minimum crew is 3, two pilots and one crew member. While not ideal, this is a regular occurrence for operational reasons, so it's part of regular training.


This is incorrect. The sibling comments posted earlier are correct.


I had to read it twice, it could have used the addition of the word helicopter after the phrase "only one" to make it absolutely clear what was meant.


1 copter with 2 pilots


The helicopters fly as pair = 2 helicopters.

One helicopter has 2 pilots


One helicopter with two pilots, as compared to two helicopters. Perhaps try checking yourself before yelling at others.




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