February 16, 2025, 22:52:00 GMT
permalink Post: 11829513
The basic explanation is that discretionary functions involve policy judgments which, in the view of Congress, cannot be "second-guessed" in lawsuits over alleged federal agency negligence. The other half of the equation is that immunity is waived for "ministerial" actions, sort of (to over-simplify) plug-and-chug activities.
Is the construction and operation of the airspace around DCA a matter of policy judgment? I can almost hear the lawyers planning to file suit arguing that airspace rules which make simple, obvious sense are not derived from policy judgments. I can almost hear them issuing subpoenas (through the necessary international process) of Network Manager or MUAC senior managers to gain testimony that in European airspace, as others have observed about Heathrow, the airspace rules are more like "plug-and-chug" than the sometimes esoteric, and usually vague and/or ambiguous, factors which inform the choices made in - offensive phrase coming - "the policy world."
Is the construction and operation of the airspace around DCA a matter of policy judgment? I can almost hear the lawyers planning to file suit arguing that airspace rules which make simple, obvious sense are not derived from policy judgments. I can almost hear them issuing subpoenas (through the necessary international process) of Network Manager or MUAC senior managers to gain testimony that in European airspace, as others have observed about Heathrow, the airspace rules are more like "plug-and-chug" than the sometimes esoteric, and usually vague and/or ambiguous, factors which inform the choices made in - offensive phrase coming - "the policy world."
If we took the FAA to be undertaking "plug and chug" regulatory and procedural activities, unburdened by political considerations and at risk of having EASA or UK CAA regulations and procedures held up as comparators in negligence cases against it, then I think it is highly unlikely that FAA regulations would be as permissive as they are in respect of visual separation and runway occupancy (the two most obvious and frequently cited points of difference, at least where airline operations are concerned), or that DCA\x92s helicopter routes would have existed. So why such a difference in approach? Economic factors are usually held up as the reason, and I fear this takes us away from "plug and chug" regulation into policy territory where immunity would seemingly apply.
I very much doubt that any politician, corporate lobbyist or general would explicitly advance the argument that occasional accidents are a tolerable price for the traffic capacity enhancements enabled by visual separation. It'll be interesting to see whether the NTSB forces that argument into the open, or enables it to be avoided by distracting itself with altimetry and other such matters.
Last edited by Easy Street; 16th February 2025 at 23:35 .
Subjects
DCA
FAA
NTSB
Separation (ALL)
Visual Separation
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February 16, 2025, 23:09:00 GMT
permalink Post: 11829529
Understandable, given that he mistakenly thinks he can see the CRJ ahead of him. It hasn't yet started moving to his left to line up with runway 33, so he thinks it is still south of the Wilson bridge (it being difficult to judge distance from points of light at night, and impossible through NVG). He therefore thinks he is OK to plow right on and is not too worried about being 78 feet high given the distance between the aircraft.
He doesn't know his mental model is dead wrong because he latched onto the wrong aircraft in the cluster of 4 visible when the traffic was called to him a couple of minutes ago.
He doesn't know his mental model is dead wrong because he latched onto the wrong aircraft in the cluster of 4 visible when the traffic was called to him a couple of minutes ago.
Last edited by Easy Street; 16th February 2025 at 23:38 .
Subjects
CRJ
Night Vision Goggles (NVG)
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February 19, 2025, 22:35:00 GMT
permalink Post: 11831807
(I've assumed that the altitude is recorded in the closest bin to the actual value. If that's not the case then the error bars would be 25 feet in one direction or the other depending on whether it rounds up or down. An ADSB geek would know. I am also itching to know whether the origin point of your glidepath lines has been adjusted to the same EGM96 height datum as the ADSB values...)
Subjects
ADSB (All)
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February 21, 2025, 01:51:00 GMT
permalink Post: 11832665
Also, I suspect the military requirement for the routes means they have to be as weather-proof as possible, meaning as low as possible. The route heights are given as maximum heights to be flown when the ceiling permits, and can be underflown when required for weather unless stated.
Subjects
Separation (ALL)
Vertical Separation
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February 22, 2025, 11:12:00 GMT
permalink Post: 11833584
I can think of one: you apply IFR separation standards (the minimum in the US is 1.5nm/500\x92?), at least for night operations. If two routes come closer to each other than that in either dimension, e.g. DCA RW33 approach and helicopter route 1, then traffic must be actively kept apart
However, from a US point of view, this is arguably the solution which was in place on the night. It's just that the means of actively keeping the traffic apart, ie visual separation, failed. I am prepared to accept that FAA-style "visual separation" is slightly more robust than "see and avoid" in that it requires ATC to confirm that the pilot has the specific traffic in sight before relaxing separation minima, but the question for the FAA is whether "slightly more robust" is good enough when airliners are involved, particularly at night given the increased potential for misidentification.
I am not sure the subsequent line of discussion over how Class B requires ATC (not pilots) to separate all traffic is a very productive one. Any separation instruction given by ATC relies upon the pilot executing it, for instance by maintaining the cleared altitude. Here, it relied on the pilot not colliding with the specific traffic he had confirmed visual contact with. So far as the FAA is concerned, that's a sufficient degree of control and differs from the "see and avoid" principle applicable to VFR/VFR in Class C, and VFR/Any in Class D. Again, the question is whether that's appropriate.
That last point gives me an opportunity to make an observation I've been pondering for a while. Many European airport control zones are Class D, where on a strict reading of ICAO, VFR traffic is not required to be separated from IFR. But how many of us know a Class D zone where the controller gives traffic information and lets VFR traffic merge with IFR under see and avoid? In practice, European and especially UK ATC exercise a greater degree of control than is strictly required by the ICAO classification. At least in my experience, US airspace is operated closer to ICAO specifications ("visual separation" nothwithstanding).
Last edited by Easy Street; 22nd February 2025 at 11:31 .
Subjects
ATC
DCA
FAA
ICAO
IFR
See and Avoid
Separation (ALL)
Traffic in Sight
VFR
Visual Separation
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February 22, 2025, 11:57:00 GMT
permalink Post: 11833610
I'm surprised that this is your conclusion. I think what I take away from the conversations on the night was that ATC was divesting himself of responsibility, and the helicopter was trying to expedite his sortie, and nothing in the 'system' prevented them from doing that. Removal of visual separation as an option IMHO deals with that hole in the cheese.
It seems like you're suggesting that the helicopter might ignore instructions to hold before the tidal basin ?
Subjects
ATC
FAA
Separation (ALL)
Visual Separation
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February 22, 2025, 18:56:00 GMT
permalink Post: 11833817
From what I understand the delegation of separation used in the US is based on the "see and avoid ", It is basically delegating the positive control (ATC separation instructions ) from the controller to the pilot , who has to acquire the traffic visually and maintain visual contact and maneuvers to avoid it . = traffic info from ATC + See and avoid.
When genuine "see and avoid" applies (Class C VFR/VFR, Class D VFR/Any) the controller does not need to confirm that VFR pilots have visual contact before allowing separation to reduce, because there *are no* separation minima. At least, not according to ICAO.
As I mentioned earlier, European and especially UK ATC tends to apply more stringent separation than ICAO requires. The 'ATC duty of care' argument in the UK results in its Class D being operated in a similar way to US Class B, in my experience.
Last edited by Easy Street; 22nd February 2025 at 19:10 .
Subjects
ATC
FAA
ICAO
See and Avoid
Separation (ALL)
Traffic in Sight
VFR
Visual Separation
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February 23, 2025, 12:09:00 GMT
permalink Post: 11834211
When operating in the USA (20+ years ago) I was told, "if ATC ask if you can see XXX traffic, say negative."
If everybody denied visual contact with the other traffic in IFR conditions then ATC will be really pissed, but will have to provide you separation. Isn't that still the case? You can never be completely sure that what you can actually see is the traffic ATC want you to see.
If everybody denied visual contact with the other traffic in IFR conditions then ATC will be really pissed, but will have to provide you separation. Isn't that still the case? You can never be completely sure that what you can actually see is the traffic ATC want you to see.
Lufty at SFO
ATC will still have to provide you with separation, yes. But some US airports have too much traffic to operate without pilots accepting visual separation, so you may have to land elsewhere. Hence the discussion upthread about the inseparability of regulation from policy, economics and (ultimately) politics.
Post #10 on that thread...
Subjects
ATC
IFR
Separation (ALL)
Visual Separation
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March 08, 2025, 09:24:00 GMT
permalink Post: 11843284
Subjects: None
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March 08, 2025, 21:18:00 GMT
permalink Post: 11843640
As for "do not cross final 33 before CRJ"... that'd still have given too much responsibility to the helo crew, in my opinion. They'd have suffered a crushing breakdown of their mental model as it became clear the lights ahead of them weren't going to land on 33 before they crossed the approach. Would that dawning reality have caused then to widen their search and see the CRJ? Possibly. But I doubt it. Human nature in high pressure situations, like NVG flying over a dark river in a city, is to keep pressing on with a flawed mental model.
"Hold at Hains Point", from a second controller with capacity to keep watch over two converging tracks, was what was needed to save the day here - and to cover up the underlying organisational failings for a while longer.
Subjects
ATC
CRJ
FAA
Night Vision Goggles (NVG)
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March 22, 2025, 12:48:00 GMT
permalink Post: 11852019
Of course in this case the thing known to degrade safety is "see and avoid", the regulator is the FAA, and the relevant parts of the user community appear to be "near as damn all of it". Focusing on the Army pilots' failure to achieve it would be a neat distraction from the much more difficult question (for everyone) of whether it is an appropriately safe means of separating from airline traffic. The nice NTSB diagram of Route 4 and the 75 feet spacing dodges the issue that neither the controller nor the Army pilots assumed that procedural separation existed; visual separation was being applied.
The permanent closure of Route 4 could be seen as acceptance that this was an unsafe basis on which to permit operations. However it still misses the point. The route was capable of being operated safely, for instance by holding helicopter traffic or avoiding use of runway 33 when needed to prevent conflictions, but that would have been tacitly to accept that visual separation was unsafe. Closing the route also only fixes the issue on one runway at one airport. Where next?
Last edited by Easy Street; 22nd March 2025 at 13:08 .
Subjects
ATC
FAA
NTSB
Route 4
See and Avoid
Separation (ALL)
Visual Separation
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March 26, 2025, 08:23:00 GMT
permalink Post: 11854385
I think it's also important to recall from way upthread that at the point of being called as the factor traffic by ATC, the CRJ and the AAL aircraft behind it in the stream were extremely close together in the helo pilots' field of view, because the circling manoeuvre had barely begun. A very illustrative diagram was composed by a YouTube contributor (not one of the usual aviation commentators) which made the point very well. I'm mildly surprised the NTSB didn't produce such a diagram of its own at the initial report stage.
Subjects
ATC
CRJ
NTSB
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October 21, 2025, 08:54:00 GMT
permalink Post: 11973542
In respect of the Army pilots' height keeping, how relevant might it be that the
FAA Airman Certfication Standards for helicopter instrument ratings
(IH.IV.A.S1 and elsewhere) specify a required accuracy of plus or minus 100 feet? An argument that the pilots were negligent for deviating by less than that would surely be open to challenge, even before considering that they were flying visually and therefore would have been expected to spend more time looking outside than scanning instruments (leading to less accurate height keeping). This would bring the focus squarely back onto the FAA's airspace management and control. Was it reasonable to expect pilots to fly at precisely 200 feet, plus or minus zero?
Subjects
FAA
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October 21, 2025, 14:54:00 GMT
permalink Post: 11973706
What has that got to do with this event? They were not on an IFR flight plan.
Also, as an aside the term "altitude" is typically used in aviation.
(Yes, I know that DH for a precision approach is "decision height"...and HAT is shown on approach plates (Height Above Touchdown).
Also, as an aside the term "altitude" is typically used in aviation.
(Yes, I know that DH for a precision approach is "decision height"...and HAT is shown on approach plates (Height Above Touchdown).
Why do I think the IFR ACS might be relevant? Because it specifies the accuracy the FAA requires of skilled pilots when separation is to be achieved by procedural means. The fact that the "designed" separation between the 33 approach slope and the top of Route 4 was less than the allowable error for skilled pilots could be used to rebut an allegation of negligent flying as the cause of the accident. The Army no doubt has its own standards document, but I'd be surprised if it was radically different. Building the argument off the FAA's own document forces the focus onto its route design and visual separation procedures.
As to why this might be relevant to VFR flying - is it your opinion that parameters should be flown more accurately in VFR than in IFR? In any case, I have now dug further into the ACS and the same tolerance is prescribed for commercial VFR helicopter operations (see CH.VII.A.S8).
Last edited by Easy Street; 21st October 2025 at 15:16 .
Subjects
FAA
IFR
Route 4
Separation (ALL)
VFR
Visual Separation
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October 21, 2025, 16:33:00 GMT
permalink Post: 11973744
Subjects
Blackhawk (H-60)
FAA
NTSB
Preliminary Report
Separation (ALL)
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October 21, 2025, 18:22:00 GMT
permalink Post: 11973780
Subjects
FAA
Route 4
Separation (ALL)
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October 23, 2025, 08:11:00 GMT
permalink Post: 11974792
The 200 ft altitude restriction seems to have given some the impression that helicopters were routinely passing directly below the approach traffic, but that's not the case. And even if it was, it wouldn't really be relevant to this accident. The Blackhawk pilots weren't trying to duck underneath the plane, they never even saw it.
I agree with you, by the way - my point being that the case for Army pilot negligence isn't as obvious as it might first appear.
Last edited by Easy Street; 23rd October 2025 at 08:56 .
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Blackhawk (H-60)
CRJ
FAA
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December 20, 2025, 19:34:00 GMT
permalink Post: 12008689
I've seen pictures of US military aircraft using devices such as Sentry to feed EFBs with ADSB data, but have no idea if that's widespread throughout the services or indeed was in use during this accident. However, what I do know is that it would be very unlikely that either helo pilot would have the capacity to scan down onto a knee-mounted EFB while flying VFR over a dark river on NVG at 200 feet (and in the non-handling pilot's case, monitoring the handling pilot's height and talking her down). Integration of an audio warning from the EFB to the intercom system would be needed to draw attention to conflictions, and I very much doubt that would have been implemented. Remember, they thought they had the traffic in sight, so there was nothing pressing them to check for other traffic given they were in (supposedly) fully-controlled Class B.
Subjects
ADSB (All)
Night Vision Goggles (NVG)
Traffic in Sight
VFR
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