Posts about: "NTSB" [Posts: 232 Page: 7 of 12]¶

Hi MechEng , it's been a while since it was discussed.

Here is the NTSB report/transcript and another transcript here . I couldn't locate the one on Prune way, way back but these 2 will do!). ATC specifically call the a/c sidestepping to 33 as the a/c PAT needs to identify. The ATCO even tells PAT what type it is. PAT then say they have "it" visual. Sadly, "it" wasn't the sidestepping a/c, it was another one. But no-one figured that out ...... till seconds before the crash. This initial exchange, according to the transcript, was about 2 min before the collision. It's only then, on the basis that PAT says they have seen "it" and, by implication, will visually avoid it, that ATC issue the clearance on down Route 4.

There was a lot of discussion earlier on in this Thread about how on earth PAT could be reliably expected to pick out the subject a/c from the rest of the stream of arrivals and at that distance (6 miles rings a bell).

It's only seconds before the crash that it appears that the poor ATCO suddenly starts to suspect the PAT crew are actually looking at a different a/c to the one he had asked them to identify and pass behind. But, by then, it was too late for him to figure out a solution to give to PAT.

As I said, this was all discussed many posts ago so it's easy to forget the details. Hope the links help!

Cheers, H 'n' H

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.

I don’t think the radar track shows a last-minute right turn turn by the helo (I looked at the post #848 image). The NTSB preliminary report states the helo had a 1.6 deg left bank at the time of the impact. Although the report notes the evasive maneuver by the CRJ (elevator, pitch), there’s no mention of evasive maneuver by the helo. I think you might be biased by some of the early but inaccurate MLAT tracks that showed a significant right turn by the helo prior to impact.

I see the radar recording differently but the NTSB will settle that for us , that last second 1,6 deg left input might just be e a manual correction to correct that previous right tracking , we'll see . Anyway , even if they were flying t straight , the absence of a left turn is for me the riddle , as if they had visual with either aircraft the only way to laterally avoid was a left maneuver..

Disappointed to hear that. Searching for or expecting genuine emotion in the political theater of a congressional hearing is like searching for virtue in a brothel.

I also watched the hearing and learned little new from the parade of platitudes and witness obfuscation. I thought far too much time was spent on ADS-B (an acronym which Maria Cantwell is incapable of uttering correctly). No discussion on use of visual separation. There were a few new points:

1. Cause of spurious DCA TCAS alerts. ME links in related thread.
2. When NTSB examined other Blackhawks of 12th AB fleet, found significant number which did not transmit ADS-B even when ADS-B switched on. One helo (accident helo?) was found to have not transmitted ADS-B for past 700+ days.

Dumbo Question 1.

How would the successful transmission of ADSB Out information by the Blackhawk have changed the outcome on January 29?

After watching the US Congress “grill” the military, FAA and NTSB how could they participate in a conspiracy of silence…

The NTSB will be seen as either very dumb or deceitful or both.

Now what was the number of the Q ANON Pizza shop, I feel like some truth tonight.

Send it to me via Signal. What a joke! The relatives of the crash victims were there to watch the farce.

The small elephant in the room…

Unfortunately, and I hate to say this, I have reached a conclusion beyond those reached by other posters to this forum, to wit:
The US Army, in order to meet its mission requirements, really does not want civilian pilots (commercial or otherwise) to know where its helicopters are. My evidence for this is: The eagerness of the US Army pilots to assume responsibility for seeing and avoiding commercial aircraft; The DCA tower procedures that do not allow civilian fixed wing pilots to hear the conversations between the tower and the helicopters; The Army practice of turning off ADS-B out while on missions and training flights that follow mission profiles (as explained by the USA general in the hearing); The Army's refusal to produce the memo regarding its use of ADS-B to Senator Cruz.
Should the policies adopted by the US Army be regarded as the fundamental cause of this accident?

Dumbo Question 2

Given the extraordinary level of interest in the US Army Blackhawk carriage, activation and transmission of ADSB Out information in the US Congress in the last couple of days, do you think the NTSB could have confirmed (facts) how that information would have been displayed in the cockpit of the CRJ and the ATC TWR cab at Washington DC Reagan?

The small elephant in the room.

VHOED191006 , and others interested.

Dumbo Question 3

As you are no doubt aware TWR Visual Separation is a very powerful tool / method in the eyes of the controller or in the eyes of a delegated pilot. (Literally and metaphorically speaking, i.e pun intended.)

It is the very basis of ATC Aerodrome Control. Sophisticated use requires experience and excellent situational awareness.

I just wonder how many (if any) of the “reported” near collisions in the NTSB Preliminary report going back 4 and 14 years respectfully included perfectly safe visual separation?

The small elephant in the room.

ATCDumbo
I'm all ears, excellent point. This focus on ADSB-OUT, and ADSB-IN is really a furphy in terms of this investigation to determine the facts, the whole facts and nothing but the facts.

If 5342 had ADSB-IN then PAT25 not having or not displaying ADSB-OUT could be relevant depending on 5342's cockpit display, the training of the pilots and their scanning.
5342 didn't have ADSB-IN so move along, move along, nothing to see, these aren't the droids you're looking for.

**Caveat. If the TWR display were using ADS-B for their updates and to generate Collision Alerts then the absence of PAT25 ADSB-OUT could be relevant.
But would the TWR ATC even know (or care) whether PAT-25 was ADSB-OUT capable. TWR ATC involves looking out the windows and judging the relative positions of aircraft.

Note: ATC display systems are not referenced in the NTSB Aviation Investigation Preliminary Report. This seems to be a glaring omission. So perhaps the NTSB are either very dumb or deceitful or both.

To further illustrate the focus on ADSB. Figure 1 Google Earth image with preliminary ADS-B data for flight 5342 and radar data for PAT25.
The ADS-B plots are 1 seconds intervals, the radar data are 4 second interval (as stated during US Congress Q&A).
So the focus is on the whizz bang ADS-B kit rather than what the ATC saw on their display.

There is reference to ATC radios, and 5342 was on frequency 119.1 MHZ and PAT25 was on frequency 134.35 MHZ. The ATC could've had them on the same frequency (changed PAT25 to 119.1 MHZ) but this would be abnormal. ATC Voice Switch systems like Frequentis, SITTI and Rohde & Schwarz typically have a frequency coupling, whereby controller broadcasts on multiple frequencies (2 or more) and voice communications on one frequency are heard on the other. In this case, ATC would broadcast on 119.1 MHZ and 134.55 MHZ and 5342 would hear instructions for aircraft on 134.55 MHZ, and PAT25 would hear instructions for aircraft on 119.1 MHZ.

Yes, visual separation is typically used close to an aerodrome where the ATC is applying visual separation to reduce the standard from 3NM to something less, 2NM, 1NM, or even less, depending on the circumstance which includes weather (included visibility), day / night, workload to monitor the separation, plus other considerations such as equipment.

I just wonder how many of the January Route 4 Helicopter plots crossing RWY 33 Approach (post 1346) were the result of ATC issuing a control instruction to change the track to closer to the shoreline or further over water.

Use of Route 4 during RWY 33 Approaches or RWY 15 Departures is possible providing a clearance limit is imposed prior to assigning relevant traffic, positive control instruction(s) and in the case of 5342, advising them of the relative position of PAT25 and that PAT25 would be maintaining separation from them.

Example for Route 4 southbound would be a clearance limit of Hains Point. Helicopter would be released past this point when there is no conflict (nil traffic) or assigned separation to avoid (pass behind). If there is a in-line stream of arriving traffic then Route 4 may not be available.

Sydney KSA has something similar for one of their helicopter routes - BONDI 5 (yep, named after the beach), delays may occur when RWY 07 is in use for DEP, or RWY 25 is in use for ARR. Further, the route is not available when RWY 16 PRM approaches are being conducted. Sydney KSA helicopter routes are in text form - TRACK TO..., TRACK VIA..., EAST OF..., and the INBOUND routes to Sydney KSA have a clearance limit in the clearance. A map display is very useful however it should be based on route descriptions. Perhaps the committee of 17 knows the history of the helicopter routes in and around DCA.

Since we\x92re discussing the DCA accident, let\x92s be clear about U.S. terminology as specified by 7110.65.

There is tower-applied visual separation . That is not relevant to the DCA accident.

There is also pilot-applied visual separation . That is what PAT25 requested and the LC approved.

As for the perfectly-safe visual separation, the DCA accident might have been avoided had the LC applied all of the elements of pilot-applied visual separation; i.e.

I'm applying SLF/attorney license here (hey, there's poetic license, so why not?) of repeating - with some editing - a post I placed on the R&N thread about testing at DCA.

1) Regarding ADSB-Out being turned off, what is the reason there was such emphasis placed on this at the recent Congressional hearing (and just scoring media points per usual in Committee hearings doesn't qualify as a "reason" in this context). Is the reason that there are objections to running the kinds of tests in question (per the R&N thread) in or near DCA airspace? Is it valid to say there is no connection to the chain of causes-and-effects which led to the midair collision on Janaury 29 (but if there is, what is that connection, specifically)? Is the reason some connection with the occurence of TA's and RA's on TCAS as documented by NTSB? (although other posts on the R&N thread indicate that ADSB-out isn't connected to TCAS advisories . . . that is, if I understood those other posts). Or something else? I'm dismissing the mere fact that FR24 doesn't provide information to enthusiasts as the reason for such emphasis in the hearing.

2) If the Army operates certain "missions" with ADSB-Out turned off, and it conducts these operations based on national security concerns, my initial thought about this practice is, . . . . . . . hey, isn't there a discretionary function involved in deciding what avionics (or electronics system if this isn't within the technical definition and scope of "avionics") to operate based on national security concerns? So the Senator declaring that there is "no justification" seems to deliberately overlook the existence in the Federal Tort Claims Act of the exception. (I realize there has not been, to my knowledge at least, any lawsuits filed yet. But they're certainly going to happen.)

Of course, this all said, the indictment of the structure and operation of the portion of the NAS in which DCA is situated might (as suggested previosly) itself be adjudged inconsistent and non-compliant with basic standards of aviation safety. The only not-crazy-sounding justification for that state of affairs would seem to be "but we have to move traffic in volume." As a legal wrangle over whether that obvious judgment of a "policy" nature is or is not a proper basis for keeping federal immunity in place in a particular matter . . . I am quite skeptical such a legal wrangle would ever make it as far as an actual courtroom proceeding. But will Congress not try to manuever itself into the issue for all the usual reasons - some people want actually to address the problem constructively, some just want to please their donors, and some just follow the crowd, or so it always appears.

3) Something about discovery in civil litigation was underscored by the exchange in the video clip: there's an Army memo, dated Aug. 9, 2024 as referenced by Sen. Cruz, about operating in the NAS with ADSB-Out turned off. And the Army so far declines to turn it over to the Committee. (Applying the rough equivalent of a pre-snap read by a QB, the manner in which the Army witness replied to Sen. Cruz's questions gave the impression that the Army and DoD will strongly resist the memo in question becoming public.)

[Okay, I'll refrain from speculating how much fun it would be to decide which officer or officers would be presented as the Person(s) Most Knowledgeable about the matters discussed in this memo (on the Army side, receiving the Rule 30(b)(6) deposition notice), or similarly, how much fun would be had by counsel describing the "subject matter(s)" which must be specifically iterated in a Rule 30(b)(6) deposition notice (on the plaintiffs' side).]

4. I'm very determinedly hoping this won't be read or even misinterpreted as an offensive point. In the YT video produced by "Mover" in which he interviewed a former Army helicopter aviator (post 1228), it was possible to draw the impression that Army helicopter pilots operating in the airspace in which DCA is situated have a certain attitude toward FAA ATC. That is, the Army operates - one could get the impression - in its own "airspace system" and deals with FAA ATC only as much and only as quickly as necessary. Listening to the pertient Jan. 29 ATC R/T, and knowing the visual difficulties presented by the basic facts of nighttime in that specific area of the DCA airspace, plus NVGs, an observer could get the impression that the Army aviator handling the R/T was doing so in a perfunctory manner on Jan. 29.

To explain further, upthread (in post 1261) in the context of a Mover/Gonky YT video (post 1228) someone much more knowledgeable than myself observed that the way in which the Army pilot interviewed in the video described communications with FAA ATCOs in DCA airspace was as if Army chopper pilots view FAA ATCOs somewhat as a nuisance. Far be it from me to fault any pilot over any practice or custom in anything, including comms with ATCOs. But faulting any pilot is not the point. The point is that in that YT video, as related that other poster, --
"it was suggested that it\x92s perfectly OK to second guess what ATC might have said to you, reply to that, and then if no correction is forthcoming you can comply with your guess. As others have pointed out implicitly, that works if there\x92s only one error involved, but here there were three: an untrue statement, leading to a wrongly issued clearance, and a missing read back."

It is known that ADSB-Out is not active on the Army and other certain missions in the relevant airspace. Is there also a pattern or practice of operating with a mindset that FAA ATC is a necessary nuisance, to be indulged but not focused upon as closely as other airspace users? If any reader asserts this question accuses the Army pilots or any one of them in the helicopter on January 29 of negligence - that would be incorrect. The way in which the airspace had been designed, managed and operated handed those pilots a pre-determined normalization of complacency - so it appears, does it not?. They operated their flight within the system they had been given, which does not constitute negligence. The designers, managers, and operators of that system . . . well, it will be for the courts to sort out whether the exception to the removal of federal immunity to tort claims applies to those systemic level actions, or not. If it were not for the existence of the discretionary function exception, I personally believe the race to the courthouse would already have been a feeding frenzy worthy of the most biting negative stereotypes about lawyers.

Speaking of immunities, wasn't it generally believed that the airspace within the NAS, and especially airspace in which major airports in the United States are situated, was immune to midair collisions, in general and not only collisions sudden, without actionable warning, and with at most two or three seconds' knowledge of impending death and disaster? Mere SLF/attorney as I am, I had believed that. It follows, but only under that mindset, that what occurred was obviously negligence, and even gross negligence. The point is, expect the lawsuits to be, in a word, consistent with the ugliness one feels seeing the wreckage pulled from the Potomac, or reading about the backgrounds of 67 people. Or both.

Let's say that the reasoning you have described is not only valid but also the dominant theme of an anticipated trial. Is it not difficult to contemplate a trial in which the central theory of liability is invoking a dread phrase, one with both the words "pilot" and "error", or at least the "negligence" version of that phrase. This would be a horrible case to see unfold. Of course the lawyers representing the families and other loved ones of the accident victims will press hard to make exactly such an unfolding happen - and their clients, the families and other loved ones, will be pressing just as hard as the families of the MAX accident victims are doing in the criminal case in federal court in Texas, if not harder.

This is not a reason either to dismiss, or to claim decisivenesss of, any particular legal reasoning here. It is instead recognition that reasoning which points to the request for visual separation and then the failure to maintain it as the basic cause of the accident will produce a very unpleasant legal case. Think of the Army units assigned to this sort of duty, how they are trained to treat "continuity of governement" and transport of highly important (presumably) officials as a kind of higher calling - at least that's the impression given by several statements or articles. And one set of their fellow servicemembers are put in the position of being blamed, and not present even to try to explain what happened. And that's in addition to usual strident reluctance to assign responsibility to aviators in situations where things go wrong.

Over the past several days, it has become clearer that the airspace environment was indeed so compromised that, as SLF/attorney without technical expertise or even knowledge about airspace design, management and operation, it would be best to stop trying to refine an understanding of the causes and effects and instead leave the puzzle-solving aside until the NTSB report is completed and released. That said, the way Sen. Cruz pressed witnesses last week suggests that waiting for the report will be a difficult task.

I appreciate any and every acknowledgement of efforts to make positive contributions to this forum - thank you for your post!

As other posts have admitted I am biased against assigning responsibility in situations such as this one to any aviator. There additionally may be a somewhat unique factor in this case too (involving some personal history about Army aviation maintenance training circa 1975, enlistment as an alternative to dead-end mindless jobs, and studying German in high school and for a couple of semesters in college so that if I ever went to Germany in the Army . . . ).

NTSB chair pointing out the horizontal position of the helicopter during last weeks testimony.
The altitude is still uncertain because of difference between jet and heli values and destruction of the heli altimeter. So work on that is continuing with a focus on other sources.
But note the 75 ft separation is a maximum. So if the heli was at 200ft then it was on the glide slope.




Another interesting point is that mixed heli and fixed wing is forbidden in the yellow zone (permanently), and ADSB mandatory in the red zone. With routes 4 and 6 cut.

See post below

Another interesting point is that mixed heli and fixed wing is forbidden in the yellow zone (permanently), and ADSB mandatory in the red zone. With routes 4 and 6 cut.



another item in the testimony was that generally 100% army helicopters flew there with ADSB set to OFF.

and that the accident heli might have put their ADSB to ON, but that the FAA had not received ADSB data from this heli in 730 days.

on ADSB there also was a difference between the Mike and Lima models,

NTSB chair indicated there was a lot more factual information. I wonder if the pull from Congress will lead to a change in the normal process, and release more factual information (with an appropriate disclaimer).

Refer to ATCDumbo Question 1!!

ATCWatcher Thank you…It’s like pulling teeth but we will get there eventually ….

No thanks to the NTSB for the selective choice of facts…What should I expect in a country of fake news and alternative facts?

As for your comments re if the CRJ had ADSB_IN; exactly ….welcome to my nightmare!

Shock horror The Holy Grail turned out to be the holy hand grenade!!!

Re all lawyers reading… Put that one in your pipes and smoke it!

Always look on the ….. Now what pizza to order tonight

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

About those discussions at senior levels . . . If your reference to such discussions was meant to include not only within a given airline, but also some or all of the cadres of senior officials in the industry, U.S. government, international colleagues, and think tanks - those are the same discussions which are supposed to be going on now, in light of the NTSB's pro-active responses to the accident. Although it is a limited sample, in the accidents in which Board processes have been involved in the time I have been trying to keep up via PPRuNe and other information sources, I can't recall a similar "urgent recommendation" addressed to FAA as NTSB issued in this matter. Safety Alerts to Operators (SAFO's) yes, such as after Air Canada "There's no one on 2-8-Right but you" 759 in San Francisco in 2017. But not the same as what has issued from NTSB now. Perhaps I missed some salient details but the review which FAA became instructed and/or motivated to conduct would have a total NAS scope.

Or maybe such a review will, regrettably, require an Act of Congress (it should not require this, but, you know, K Street, campaign donors, the seniority system, and the generally stellar academic and career experience required prior to election to the Congress . . . . too bad elected represenatives are not required to build hours first).

"There's no one on 2-8-Right but you" 759 in San Francisco in 2017. But not the same as what has issued from NTSB now. Perhaps I missed some salient details but the review which FAA became instructed and/or motivated to conduct would have a total NAS scope.". (WillowRun hat tip,)

Howdy. Are you aware of any interviews the AC pilot did?
The video is damning. Besides thinking Charlie was the runway, he missed a direct hit on the tail of a holding aircraft by less than 100 feet.

Enjoy your thoughts, and objectivity....bb

Thanks for the hat tip & etc.

Not sure of what video you've referred to about the Air Canada incident. But yes, without a doubt, it was a very close call. Only a slight difference in the height above the taxiway for the Air Canada flight, or slight delay in initiating the go-around . . . and many factors which play into those parameters (reaction time, etc.).

I don't recall any interviews of the aviators being published (but I haven't run off to go looking through sources available online). Somewhat more in the direction of drift, the thread on the incident was useful background for trying to follow and understand the Lufthansa diversion occurrence.

Edit and slight correction: NTSB Incident Report, NTSB/AIR 18/01, PB2018-101561 (Sept. 25, 2018) does include information from the incident investigation interviews of the pilots (including several quotations) but to my knowledge the transcripts of interviews were not disclosed to the public.