Posts about: "See and Avoid" [Posts: 45 Page: 2 of 3]¶

So when the helicopter pilot requests visual separation and is granted it by ATC does that mean he can go above 200\x92 and the responsibility lies on him to see and avoid or should he still maintain 200\x92?

Hello fellow flyers, I am a 65 y/o retired pilot. I served 20 years in the Navy flying P-3C and trainers then served another 20 years flying for Southwest Airlines, nine of those years as Captain. Also, I am a graduate of the Naval Post Graduate Aviation Safety School with extensive hands on experience in military mishap investigation.

I have mostly enjoyed my latest years of not sitting at the front end of a jet. During my 40 years of flying people, I never really felt the stresses of being responsible for the well being of so many. Now that I spend most of my days on my boat fishing or growing tomatoes in my garden, life's pressures are minimal. This has opened my eyes to the gravity of the enormous responsibility I held on my shoulders, for the safety and well being of so many.

I have always had the mindset not to "arm-chair" quarterback any aviation mishap, regardless of how tempting it may be. But the aviation mishap that occurred at DCA on the evening of Wednesday, January 29 has compelled me to speak out.

Was it preventable? Sadly, It was entirely preventable.

How did it happen you may ask. After all both aircraft were clearly operating normally up until impact. First lets clear up one detail both the President and our news media has consistently made error.

Elevation refers to the height above sea level of the ground. These two aircraft were flying altitudes, not elevations. Aircraft fly altitudes and above 18,000 feet they are called flight levels. Example, flight level 180 is 18,000 feet. The ill-fated regional jet was at approximately 325 feet when it was impacted by the Army UH-60 helicopter. I have flown into Washington National since the first days Southwest began operations at DCA. I was already a Captain at this point, and I can tell you this airport is one of the most technically challenging of any I have flown.

However, that is not why this disaster happened.

I would be very surprised if the RJ black box revealed either of the two young PSA pilots were aware up until the moment of impact. Why you may ask? Because when you are flying a jet on short final, at 325 feet, you are focused on the flare and touch-down point on the runway. Perhaps the young First Officer may have seen the UH-60 just with enough warning to make a call-out, just prior to impact. From the angle of impact, very unlikely the more seasoned Captain would have even been able to see anything at all. If the First Officer was making the landing, it is most certain that neither of them saw it coming and there was nothing said on the microphone. I have no doubt, the pilots on the regional jet will be completely vindicated. In any aviation mishap, there is a chain of events that lead up to the accident. If any one of the links in the chain are broken, the accident will not happen. In this case, there are two remaining main causal factors.

DCA control tower: Tower controller made a fatal error in communicating with the Army UH-60. Time was clearly critical and was wasted by asking the H-60 if they had jet traffic in site. Clearly, they did not. What should have been said in a very assertive voice, "PAT25 (UH-60's callsign), IMMEDIATE TURN TO XXX HEADING, CLIMB AND MAINTAIN XXX ALTITUDE TO AVOID COLLISION. Tower was no help at all. First they cleared the RJ for a last minute change to 33, and then failed to ensure their approach corridor was clear of traffic. In my view, the tower controller could have easily prevented this fatal collision.

Army UH-60 crew: In military aviation training, we have always have preached the importance for pilots to maintain situational awareness. That philosophy by the way is also a cornerstone to commercial aviation safety. Were the pilots tuned up to tower when the controller gave the RJ clearance to land runway 33? Had they been aware the commuter jet was going to track over the ground through their intended flight direction, something should have been said. Request vector, due to traffic! One H-60 pilot responded, yes we have traffic in site, we will maintain VFR (visual flight rules) which means "see and avoid" yes even at night. Clearly he was looking at the wrong traffic which by the way is a very common occurrence, especially at night. No doubt the Army crew was engaged in training, which may have been a distractor to situational awareness.

In the end, the chain of events were allowed to happen as did this horrible accident that took the lives of sixty-seven beautiful souls. The President is totally correct in that we need to hire pilots and air-traffic controllers based on merit and experience, nothing else! I have witnessed first hand, the failed attempts to ensure diversity while training pilots, at the expense of safety. That practice, both military and commercial aviation, needs to stop! The current administration has their hands full but I have complete confidence they will make significant headway. Clearly we need to train and educate more air traffic controllers! The shortage and perhaps poor training standards are likely the primary cause of this mishap. I have no doubt our new Transportation Secretary is on it with both feet running. We need to maintain pilot standards also. The pilot shortage resulted in the FAA reducing the flight hours required to be hired to fly commercially. Why didn't they allow experienced pilots age 65-67 to work? In this country, we have effectively dumbed down just about everything, in the name of getting everyone through.

Just like on the operating table, you want the most experienced individuals in the most demanding jobs!

Yes, but their ATC transponder was obviously operating normally in C mode. That should be enough to show PAT25 on CRJ screen as traffic, even if no RA was given (bearing in mind, they were cca 300ft AGL) It is of course completelly unreasonable to expect that CRJ crew should see or even avoid the Blackhawk incoming from (slightly) right, as they were merely 20-ish seconds from touchdown and manually aligning with the runway. Also, I believe that operating ATC transponder on Blackhawk allowed for clear view on ATC screen and I wonder if there was no alarm triggered on ATC computers - they probably do have such guard software in operation on DCA?
In another midair collision report, that happened in July 2022 at NorthLas Vegas airport, NTSB put out this:
Interviews with personnel at the air traffic control tower indicated that staffing was deficient, and most staff were required to work mandatory overtime shifts, reaching an annual average of 400 to 500 hours of overtime per controller. According to the air traffic manager (ATM), the inadequate staffing had resulted in reduced training discissions, and the management team was unable to appropriately monitor employee performance. The ATM stated that everyone on the team was exhausted, and that work/life balance was non-existent. It is likely that the cumulative effects of continued deficient staffing, excessive overtime, reduced training, and inadequate recovery time between shifts took a considerable toll on the control tower workforce.
I wonder, how this situation is with DCA ATC service.
I am not trying to blame ATC either. He issued clearance to PAT25 to cross behind and asked (and got) confirmation for CRJ in sight twice. It seems quite clear that helicopter crew did not look at the same airplane that ATC was asking about.
What baffles me here is, that it was obvious a routine procedure to let helicopters cross active runway heading less than 2 miles from runway treshold, leaving practically zero margin for error. Backups, designed to catch pilots or ATC errors (TCAS and ATC alarms) cannot catch up in short time left if someone makes a mistake, so this arrangement as based on "see and avoid" concept, in the night, with many lights in the background and a fact, that other aircraft on collision course does not move relatively on the screen, but just grows bigger. Unfortunatelly, that dot on the screen that will kill you starts growing bigger only in the last few seconds.
If I would ask ATC to cross runway heading DAY VFR so close to runway treshold at my airport with incoming commercial traffic, I would be denied 100 times out of 100 attempts. (and probably called nuts).
My guess on this tragedy is, that thru the years, the system was trying to pack more and more aircraft in the same space and same infrastructure, by gradually squeezing margins and safegueards, until one day, Jenga tower collapsed.

To be specific, para 7.9.4b of the handbook, here:
https://www.faa.gov/documentLibrary/...5-24_READY.pdf

As mentioned upthread, if not visually separated then either 500ft or 1.5mi applies.

Correct if this is all wrong, but in the accident sequence if the helo had responded ‘not visual yet, looking’ or words to that effect, then presumably a controller could allow the two to get a bit closer and then advise the conflicting traffic info to the helo again, say at 2.5mi. If helo visual, great —maintain visual separation, responsibly passes to helo.

This is what happened, although the very busy controller failed to re-state the position of the CRJ to direct the eyes of the helo crew onto the CRJ in order that they could actually see and avoid it.

However if not visual at say 2.5mi, well it’s a bit late, but the controller does still retain responsibility for separation and must apply the 500ft/1.5mi standard. Presumably instant vectors away while simultaneously climb to min vectoring altitude. Or the CRJ has to go around. Can of worms in busy airspace— helos and /or jets being dispersed all over the sky.

Much better to do a rules based system and mutually exclude intersecting IFR app/deps and Helo Visual Routes.

I will not speculate specific to the accident. One more point to add about visual sep then you guys can go back to arguing about the accident. Visual separation isn\x92t just applied aircraft to aircraft. The local controller can observe both aircraft, (even if they don\x92t see each other) and apply visual separation. Such as two aircraft that are diverging but radar separation isn\x92t established.

Could someone explain, how Twr ATCO in that particular enviroment, achieve required separation?
He is not radar qualified- so no headings or radar measurment distances applicable.
Where is prescribed what point is 1,5 Nm away from visual app for rwy 33? ( Note : Atco must achive required separation before that point)
or
At what point should be givem climb instruction for He to be 500' above arriving a/c before compromising 1,5Nm. If rate of climb is 1000 ft/min Helicopet need to climb for 40-50 seconds with the speed 180km/h it is 2 Nm or so - it means that instruction to climb should be given no latter than 4Nm from crossing point.
What is possibikity to spot particular aircraft for visual separation at distances more than 4Nm from crosssing points, duting the night and in bussy traffic enviroment?

Yes , I know it is Burund....

Here you go. I feel rage too. And I'm willing to bet that those responsible are not held to account. You can hear the, "we've looked at this and there are definitely changes we can make to increase the safety in this airspace" being warmed up. I looked at the other heliroutes charts for the US around NY & Boston, and I can't see any minimum or maximum altitudes at all. I'm sure someone who knows these areas can point out what I'm missing. But if I'm not missing anything, then it's a sign that the bare minimum is put out there for guidance, and the people who are trying to make the best of it will be hung out to dry.

So the message for everyone is to politely and firmly refuse to do things that are not in your own interest, to make copious reports through safety management systems of events that you see that breach the normal, and to stop trying to work around a broken system where you ultimately will be the scapegoat.

Absolutely . Lack of Wake turbulence separation is something that immediately came to my mind when discovering the procedure . That should have been another red flag in the Safety assessment , but I assume initially the H routes were designed with RWY 1 OPS in mind and 33 only for departures. Combining 33 Arrivals with route 4 is the initial issue .
Indeed , and there is a precedent : the 1986 Cerritos collision : the NTSB found no responsibility to ATC as the pilot of the PA28 that hit the DC9 had entered Los Angeles Terminal Control Area airspace without the required clearance. However a judge found the FAA partly responsible to make sure the families of the pax , mostly Mexicans , would be compensated , as the responsible private pilot's wealth would not have been able to cover those.
Here if you want to learn or just refresh your memory ; https://www.latimes.com/archives/la-...%20government.

As an aside , the NTSB conclusions of that collision are interesting compared to our DCA accident : ( exactly 40 years ago !)

Yes history often repeats itself . just like the PATCO history...

I agree that is a solution, indeed the obvious one from my European point of view. What I was trying and failing to think of was a route design which guaranteed separation without ATC intervention, which is what I thought meleagertoo was asking for.

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).

I'm sure it does, but UK helimeds use the suffix to indicate they are actually on a shout, rather than training or positioning.

That's not called for. PEI 3721 has a respectful and thoughtful response to your post.

I personally don't think there's anything to be gained from going down the ICAO route. The NTSB has it's own charter and that's what dictates what happens in the USA.

I can see several ways the NTSB could take this, first the obvious one. The helicopter assumed responsibility for separation when it was not able to do so, and then found itself on track for collision. That's what I would define as true proximate cause. Then there's a step back from there which says nobody should be allowed to request and receive visual separation responsibilities in Class B airspace. That would be a good result as far as I'm concerned.

And the final step, which I think is more contentious and really hard for the US to accept, is that the culture at the FAA and within the industry is to balance safety and boosterism for the industry, and I think that is a recipe for irreconcilable conflicts. I'm not holding my breath on that one.

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 ?

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. . I do not think the ICAO forefathers designing the airspace classifications had this in mind when defining class B.
Listening to the NTSB , the only ATC instruction given : to " pass behind " was not received , and therefore not acknowledged by the crew , so we are here 100% in the good old "see and avoid" scenario I would say

"Visual separation" is different from "see and avoid" in that the controller must confirm that the pilot has the factor traffic in sight before approving visual separation. The controller is only delegating the "avoid" part of the task, not the "see", which must be confirmed before the separation minima are removed. That, at least in my understanding, is how the FAA argues it to be compliant with Class B requirements. It's obviously vulnerable to misidentification of the factor traffic; don't think I'm defending it!

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.

H & H:
". . . was the strategy to use Route 4 while 33 was active something ATCers at DCA, over time, started in an effort to cut down radio traffic and speed things up? If so, had it been assessed and then monitored for adverse safety? While anecdotally, it seemed people were aware of "close calls", had any analysis taken place looking at the Databases?"

To start, no apology whatsoever needed with regard to this dialogue. I try to respect the decorum required on this forum generally (meaning as SLF/attorney something has to be pretty severe or awful to warrant apologizing to me). And although I might not explain my sense of this with enough clarity - the FAA is conducting a review (according to Secretary Duffy) of airspace management and usage rules at other airports. The explanations in your posts, including very particularly the procedures when crossing approach corridors for London City, should be read and studied by the presumably well-informed professional ATO (Air Traffic Organization) staff assigned to conduct the review. (If it seems way presumptuous for an SLF/attorney to assert what resources ATO should be considering for the review noted by Sec. Duffy, I would suggest that ATO's reputation at the moment for upholding the much-touted "gold standard" set by FAA and United States aviation in general for the rest of the world ... well, like we used to say in trial practice, it takes the other side only about three minutes in court to stain the draperies, but it will take us all afternoon even to try to clean them. Reputation lost, same deal getting it back.)

On ASIAS, actually I entirely agree with your description of where it fits into the so-called "aviation safety ecosystem" (there simply has got to be a better term). The point I'm stuck on is one that (apologies, once more) comes from litigating in U.S. courts (especially federal District Courts around the country) employment law cases. Specifically, at the start, the main task for defense counsel is to construct the "chronology". Who did and said what to whom, when, and for what reason(s). I've asserted in an earlier post that in what I see as the inevitable litigation arising from this accident, there will be teams of significant lawyers constructing, or attempting to construct, such a chronology, although it won't be about an individual employee's hiring, performance reviews, promotion grants or denials and so on. It will be how it happened that the situation which obtained in the DCA airspace, in the cockpits of the Blackhawk helicopter and the CRJ, and ATC, came to exist.

(And I say "significant lawyers" because the attorneys who handle the big and significant aviation crash lawsuits for the families of victims are kind of the polar opposite of the stereotype ambulance chaser; to the contrary, their work is opposed by big-time big-law firm skyhigh hourly rate legally privileged sharks. The lawyers suing on behalf of these crash victims - if they are the same as the legal specialists I have met and discussed stuff with in various settings - are vindicating the need to bring the truth to light. "Aviation is the safest form of transportation": it is incanted over and over to the point of making anyone who utters it now sound quite seriously performative. Yet if it is so safe, how and why did those 67 people die over and in the Potomac? So with a kind of intense ruthlessness, the lawyers who will represent the families and other loved ones of the crash victims will unearth every little sequential act and omission which led to the situation which obtained on the fateful night of Wednesday, 29 January 2025. Exactly as the quoted language above from your post asks, what indeed was the strategy, if there even was one, as opposed to little incremental changes, accelerated of course by increasing airline flight lengths under the perimeter rule.)

On this basis, I would not concur with the idea that whether immunity is available for the defendants (both the Army and FAA/DoT) depends on whether the ATCO's specific conduct on Jan. 29 was "ordered" from on-high. The "on-high" is the development, over time, of the situation that obtained that night at DCA, despite safety imperatives in the NAS and aviation sector in general - and not a specific order or instruction given on that night.

The question behind the discretionary function exception is whether the act or omission by the defendant either (1) was negligent because it failed to follow a specific rule or statutory provision (if so, no immunity), or (2) was negligent in the usual sense of the word but will nevertheless still be protected by immunity because the act or omission was based on a decision about a policy matter or question. The decision on the policy matter or question is "discretionary" on the part of the government and hence the name of the exception protecting it. The courts are reluctant, and sometimes loath, to second-guess policy decisions made by the Executive Branch (I know, irony neither intended or not intended, given certain prominent flight- and aircraft-related matters in federal court at the moment). Under the first variety of negligence, there was no policy matter being decided, just failure to do something there was a legal duty to do (basic definition of negligence). Under the second variety, there would be a valid case to be made that there was negligence - but the immunity provided by the exception for discretionary functions prevents the case going forward.

So back to January 29, the assertion I've been making here is that no, there was not a specific rule or procedure that said to do things much like you describe the procedure - de facto (unwritten, informal) though it was - for transiting across the approach path. But there certainly were higher-order rules by which FAA and its ATC functions were required to observe in consistent performance, and not merely in repeated incantation that "aviation is the safest form of transportation." In fact, I wonder if clever lawyers might take that slogan and deploy it as a bludgeon. "You're at greater risk driving your car to the airport", they always say. Oh, really? Then let's talk about the equivalent scenario on the streets of Chicago with intersecting traffic lanes (obviously not at different altitudes), similarly difficult visibility conditions at night, compounded by NVGs. possibly compounded by a training or check ride in the vehicle, and then make the case that the Chicago PD cop directing traffic, and the motorist without the right-of-way, were acting on the basis of interpreting policies about driving on public roadways. No, there is no policy matter involved - there are strict rules of the road and over-riding principles for safe driving, and the failure to observe these is negligence.

It's simplistic but it might be sufficiently illustrative. Is "see and avoid" a procedure which involves making decisions on matters of policy? or is it a higher-order safety rule which must be observed at all times?

(Not meaning to slight the point about ANSP and regulatory functions needing to be separate - entirely agree, and yet, this will be an extraordinarily heavy lift to get done in the United States. That being said, I might know some lawyer-types who are fired up about efforts to make it happen this time around.)
WillowRun 6-3

Hmmm. I'm going to extend your Chicago traffic analogy. Imagine that traffic regulations permitted things known to degrade safety, but which at least some road users wanted: heavily tinted glass, freedom to use handheld cellphones while driving, higher levels of blood alcohol etc. Would the resulting accidents be down to negligence of drivers for being insufficiently skilled to avoid causing accidents under the prevailing regulatory conditions, or down to negligence of the regulators for permitting obviously less safe things to please certain parts of the road user community?

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?

An irrelevant example.

What "rule" did anybody break in the DCA midair case?

The enthusiastic amateurs can spear the seemingly obvious culprits but that is not how aviation has become the safest mode of transport ever.

No they didn't; it wasn't a mistake, they knew which one they were avoiding. It just wasn't the one they ran into. Taking off on a taxiway is a mistake because we all know what a taxiway and runway are. But avoiding the "wrong" aircraft cannot be a mistake when no attempt or method was made or existed to verify they did have the wrong aircraft in sight.

Just don't pick on the helo crew.

This is what I hate about pilots' obligation to "lookout and See and Avoid". Weasel words written by some bright spark when the Wright brothers were flying but now exposing every pilot to a lawyer-fest when it is, in practical terms, very difficult to do these days with a mix slow and fast aircraft and busy skies.

There's more to these events than meets the eye...

Hiya Capn , that is precisely what I've been saying in my last few posts (while waiting for various builders and plumbers to get back to me!) - have a look at my last few posts. It's also worth reading Post #1365 by layman54 re aircrew to which I was responding - hence the limited reply I gave concentrating on the topic their post had raised.

My view - they were specifically asked to visually identify a/c A. Now, given the stream of a/c, the distance the a/c were away, the angle of the stream, etc, etc how could they reliably pick out a/c A? Almost impossible I'd say. But they said they had, which then formed the basis of the clearance. But, as you say, they were actually looking at a different a/c, a/c B, not deliberately, but mistakenly thinking it was the one ATC had asked them to look out for and pass behind, a/c A.

You are spot on in that there was no way for ATC or the helo crew to verify that the one the helo crew were watching (a/c B) actually wasn't the one that ATC thought they were watching (a/c A). That, as you say, was a very significant weakness. So they were on course to avoid the one they were watching. But that wasn't the one ATC had asked them to watch.

You are dead right in how difficult "see and avoid" is. I'm lucky as I only flew between small UK Regionals and, particularly when in my home patch, I often got from Twr "Visual with a/c A on Final? Join Final as #2 to a/c A!" type stuff. Worked OK when it was only me and a/c A. Any more and usually Approach sequenced me if I'd arrived SVFR by placing me under Radar Control for a short while before then handing me off to Twr to join the cct visually once faster traffic was well ahead of me. That's if they didn't forget me completely .... which happened once ...... but that's another story - they were most apologetic when I reminded them I was still on the last vector they'd given me!!!! "Sorry about that, I'd completely forgotten about you!"! Charming!

Hi layman54 , I think it's much more subtle than that. As you say, other bits of the system may put the pilots into danger but you then need to fully understand why the Pilot(s) didn't save the day. You sort of start off with the premise that the crew of PAT25 took off that evening and certainly didn't want to fly into the CRJ - so, why did they?

To say so-and-so got it wrong is often obvious ........ but why did they get it wrong? That's often very complex and can involve a lot more people and a raft of other factors and that's where the really valuable lessons are to be found. That's the real reason behind any "bias" - it's so we don't simply stop at that first person (or persons) who got something wrong, but look at what led to them doing what they did and what other factors contributed to the end result . That is the real way Safety is improved. You can then look at appropriate mitigation to try and prevent that same scenario from setting up another crew to fail in the same way at a later date.

As others have said, height and track is a red herring TBH as the deal with ATC was for PAT25 to "see and avoid" so they could have quite safely passed behind the CRJ at the same altitude or even above it - but not too close due to things like wake effects. If you can't manage "see and avoid" safely, you need to build in much, much bigger safety margins - such as holding PAT until the CRJ had landed. Many, including me, have asked how on earth the PAT25 crew (or, indeed, anyone) could reliably be expected to pick out the CRJ in that scenario especially at that range. For vertical/horizontal separation, relying on a few 10's of feet up/down or left/right is simply worthless given errors with altimeters and piloting accuracy in such a high-workload situation where it's "eye's out" navigating and looking for traffic all at a couple of hundred feet above land/water which is quite unforgiving if you get too low (I know ex helo crew who are no longer here because they inadvertently hit the sea) - not to mention any issues with NVGs (no idea, never used them!). What the NTSB implied was that, by suggesting that such a set-up as Route 4 passing under the approach to 33 was intrinsically safe through vertical/lateral separation, was madness. The route was pulled almost immediately pretty much on that basis.

So, for example, based on the difficulty in picking out the correct aircraft from the inbound stream, one of the many questions I've been asking myself is "Why were the PAT25 crew so willing to say they had the CRJ in sight (twice they said that) in that environment?". Had that become "normalised" on the Sqdn, or were the risks of miss-IDing a/c not being adequately highlighted in Local Orders, particularly given the geometry of that specific set-up? There may be several reasons - that's for the NTSB to dig out. I used to do a lot of visual separation stuff Commercially and I was nervous as hell - and that was in wayyyyyyyy simpler scenarios in way better conditions usually involving just one other aircraft. ATC were the same - they were very pointed in making sure I'd really seen the a/c in question. Any doubts in my mind or the ATCs mind and it was either an orbit till traffic was well clear or, if busier, it was "Contact Approach ....... lets chat again when they hand you back to me on the ILS.". OK, the ILS bit is not applicable to PAT25 but you get my drift!

There is no one reason why this accident happened - there will be quite a list with each one contributing to the final outcome. Any one of those things, had they been different decisions by those involved on the night, or, for example, by those who designed and approved Route 4 way back when, would have saved the day. So correct not just the 1st issue you find, find out and correct ALL the issues! That's what we really need to do to stop similar things happening again, not just at DCA, but anywhere.

Anyway, hope the above helps with the context of the word "bias". It was not that long ago it was "Hang the crew! Erm, oh no! Someone else has done it now! Hang them too!" Rinse & repeat! Thankfully, we are much better at digging out all the issues these days. But we have to constantly remind ourselves to "Look for everything, not just the 1st thing you find!". Cheers, H 'n' H

WillowRun

From your perspective then, could you clarify :

Controlled Airspace, See and Avoid re same, duty of care re ATCre controlled Airspace, specifically short finals, etc?
May as well add split or proportional liability??

I am trying to get even a basic understanding of how a large helicopter flew in visual flight rules into a jetliner on short final, which was on an IMC approach, on slope. Both were “legal”. The helicopter busted altitude by 125 feet vertically, and just exactly enough horizontally. Que?

The entire thread is devoted to that!
The airplane was not in IMC, it was a clear night. They were on a visual approach to 33 and got hit by a helicopter. The helicopter said they had the traffic in sight and obviously didn't. That is the short version.

Apart from the IMC non-issue, the cause-and-effect chain of events and omissions in this accident is still under investigation. But I'll try to give some answer to your post - although I doubt my mind will latch onto anything new compared to the volume of this thread to date.

There are unknowns at this point about what information the Army PAT25 crew had in front of them about the altitude at which they were operating. There also are unknowns about the Army crew's visual scan (which, as a non-aviator, sounds to me like a complex subset of facts; I do work on maintaining strong visual scan plying limited access highways and even local streets and roads in my car but the instrument panel of my vehicle is, shall we say, somewhat limited in comparison). Add in the relatively fixed attributes of the physical environment, the background lights of the city and surrounding areas, the river, and so forth. Plus, NVGs, plus experience using same by the particular crew.

Then with all those factual matters still subject to fairly significant unknowns (at least as I am able to follow the developments), your question(s) turn to the acts or omissions of ATC. I am fairly strongly inclined to "stay in my lane" - meaning, there is a lot more about how ATC functions are performed that I don't know, compared to what I might actually have picked up from forum threads and other sources. It stands to reason that the visual separation set-up is subject to formal written rules and procedures, but I don't know to what extent these presumed rules and procedures reach down to very specific operational details. Beyond that, the signal-to-noise ratio of what more I might say would not be too especially good.

I'm reminded of the old saw that some one or another fairly well-versed individual has already forgotten more about a given subject than some smart-aleck will ever be able to master about such subject. I don't want to trip over that . . . altitude restriction.

One other perhaps non-trivial item I can add is that the attorney whose office has filed the preliminary claim (as required pursuant to the federal statute) is very accomplished in this field. I've met him at professional (Aviation Law) conferences. I have enough respect for other members of the bar who have amassed vastly larger public records of accomplishment - even those records which prompt lawyer-bashers to decry the profession and all who practice in it - not to try to pass off forum talk as the equivalent, or even merely reflective of, the serious legal thinking going on in that attorney's conference room. And many other law firm conference rooms. The issues in this matter aren't going to be simple, neat, or pleasant. Perhaps the air has been deflated out of the emotional shock-balloon the midair collision visited upon many folks; it is still my view that this was a catastrophe, wrenching in many respects the NAS all the way back to the skies over New York City in 1960 and the midair which ultimately gave rise to the formation of PATCO. And the strike, which led to, with respect to controller staffing . . . . .