Posts about: "ADSB (All)" [Posts: 130 Page: 5 of 7]¶

ATCDumbo Question 4: In three parts

BugBear : In your post above you appear to imply that the LC had to work 2 different radar screens. (Memories of Uberlingen?)

Are you sure about that?

And to manage two discrete VHF frequencies. What, two different ?headsets? Is that what you are implying?

And where do you think the ADS-B information from the CRJ was displayed in the TWR Cab, on one or more of the radar screens?

BugBear ": In your post above you appear to imply that the LC had to work 2 different radar screens. (Memories of Uberlingen?)" "And to manage two discrete VHF frequencies. What, two different ?headsets? Is that what you are implying?"

Yes. LC could hear both Heli and AA. Neither AA Nor helo could hear the other ....."
From ATCDumbo......
"And where do you think the ADS-B information from the CRJ was displayed in the TWR Cab, on one or more of the radar screens?"
One hopes. If not to both pilots, then eyes on by LC ?? How are two conflicted aircraft that close in not aware of each other ?? Doesn't AA get a chance to look for traffic??

Even if traffic is changing orientation from Four 0'clock to12 in ten seconds????

The IP radioed "traffic in sight" which clearly showed that they had the wrong plane, if any in sight and lost both situational awareness. If have no idea why the helicopter had not its ADSB turned on. Training for real sneaking at night through DCA is idiotic as we know now with 20/20 hindsight. Visual separation with several planes in the area is challenging in daylight, let alone at night. You easy miss one.

Both crews were set up to fail. Considering the near monthly DCA conflicts between helos and fixed wing over a number of years, the surprise is that a midair didn't happen sooner. The data was accumulating, but nobody caught on in time. Not transmitting ADS-B Out in busy airspace and flying in that airspace with night vision goggles restricting view is a major factor. The lack of ADS-B In in the cockpits is another. Then there's the FAA approval of a helo route with inadequate vertical separation from the 33 approach slope along with a lack of ATC procedure to ensure positive separation between helos and aircraft on approach to 33.

Somehow I doubt that all those responsible for those lapses in oversight were female - quite possibly they were all male.

I really struggle to comprehend why the helicopter not transmitting ADS-B Out is relevant to the accident. What benefit would the other two parties - the CRJ and the TWR Controller gained?
The CRJ didn't have ADS-B IN, and the ATC Surveillance system (radar) doesn't process the data.

DM as required to convince me otherwise.

Back in my post #1385, I briefly mentioned some new info that the NTSB provided at the 3/27 Senate hearing regarding the NTSB’s investigation of the functionality of the 12th AB UH-60 fleet ADS-B systems. Below is the full transcript of the NTSB’s relevant testimony:

Since the DCA accident, the flight tracking apps have shown DC military helicopter flights (PAT, MUSL) to be using ADS-B on a regular basis. However, I can also report that, a couple nights ago, a pair of UH-60s flying Route 9 passed by my house, the second about 5 miles in trail of the first. On ADS-B Exchange the first UH-60 was shown by only a generic aircraft icon with MLAT data. The second UH-60 was displaying ADS-B data. Since it was dark, no idea if these were Mike or Lima UH-60s.

Here in the shadow of JBLM, I've noticed it's about 50/50 for ADS-B on all helo makes (UH-60, AH-64 and CH-47). Whether that's an optional configuration, policy or simple breakage isn't immediately obvious.

The glider community uses PowerFLARM which can alert to conflicting traffic - provided it's working.

​​​​​​​I know of three collisions between PowerFLARM equipped aircraft where the PowerFLARM in one aircraft was not operating - in one case fatal to the instructor and student .

Quick take after looking at ADS-B data and listening to some LiveATC:

DCA LC helicopter and fixed wing positions were combined (Bueller? Bueller?)

PAT23 was a Gold Top (Mike) UH-60

PAT23 was issued two holds along Route 5: (1st) 3 mi W of DCA, and (2nd) at \x93Glebe\x94

LC then cleared PAT23 from \x93Glebe\x94 along Route 5 to the Pentagon

LC made multiple requests to PAT23 to report landing assured. It seemed to take an unusually long time for PAT23 to get to the JPN landing pad. Unclear why PAT23 (and apparently other helicopters) fly counter-clockwise; i.e., continue to follow 395 S of Pentagon (past south parking), then turn N to follow 110 (past the Metro entrance) to the JPN landing pad. Why not use the charted transition route along 27/Washington Blvd?

LC seemed unclear of PAT23\x92s position. At one point directed PAT23 to fly westbound while PAT23 appeared to be landing.

Both DAL1671 and RPA5825 go-arounds were LC directed. No pilot reports of TCAS RA heard. After checking in with departure/approach, PCT didn\x92t request reason for go-around and pilots made no comment about go-around.

Can someone explain to me the “Training value” of flying in crowded airspace with ADS-B “OFF”.

A simple training brief “ Ok Bloggins….in case of a real event we would, in order to fly covertly …when we get to [ Transponder / IFF / ADS -B ] in the checklist we would select [ OFF]. ….That would be these switches located here, here and here. Do you require training in how to move a switch to [ OFF ] ? Any questions?”

Would not, in the event of a emergency requiring the movement / evacuation of key personnel, the Washington Airspace be closed to civil traffic?

The supposed reason is to prevent the public or the \x93villains \x93 from tracking the PAT routes and times thus cluing them to perhaps attack the \x93continuation of government\x94 missions in a real emergency. Government paranoia or operations security, take your pick, yes, as we saw on 9/11 the FAA is pretty good at closing the airspace.

During various ME contingencies, I was hailed on Guard by a US Navy warship inquiring on my Mode 4 code. He claimed it was the incorrect code based on his \x93secrets\x94. We verified our paperwork that it was correct for the time and day. Never resolved the discrepancy but I can understand how friendly fire works better.

A must read/listen . The holes in the cheese layers were quite big
just a few :
-UH60-L Heli altimeters accuracy .80 -130 ft systemic error due position of the static sensors affected by rotor blades in cruise
-80 ft error deemed within acceptable tolerance by Army pilots
-flying at 300ft targeting 200ft is "acceptable" by the Army
-200ft restriction on the chart is a only a "recommended target" in VFR not a hard restriction i unless instructed by ATC ..
-Lack of regulatory oversight by FAA despite many previous incidents .
-FAA (bureaucratic) refusal to put a 'Hot spot" symbol on routes crossings.
-Lack of ADS-B compliance on Army helis, due maintenance documentation errors during installation
-lack of experience of heli pilots on specific areas due frequent rotation of staff and lack of training hours in general.
-Lack of continuity in of DCA ATC operations supervision , 10 managers in 12 years and 5 in last 5 years.

In fact on some of the Reason's layers there were more holes than cheese.

Depending on radalt for this flight mode is a problem when flying over buildings or terrain when one wants to maintain an absolute altitude relative to a common datum. If done perfectly radalt would be hammering back and forth with every chimney and tree and park and car. I'm sure they use smoothing to give something for the crew to read, but it doesn't tell how high the terrain is that the measurement is made from - it only reports clearance to the terrain when one wants clearance to other aircraft.

For TF/TA radalt is the go-to instrument, but for coordinating multiple aircraft to maintain vertical separation, barometric altitude is more suitable. The problem being that barometric altimeters are subject to a lot of measurement and reporting errors.

I am sure that GPS-RTK could be used to fix the absolute altitude with great precision, but I am also sure that depending on an easily denied measurement source on a military aircraft is not going happen.

The correct solution for operating in a civilian airspace is to use ADS-B In/Out for all manned aircraft to provide appropriate and timely situational awareness. While ADS-B is also subject to denial, it offers far greater benefit in civilian airspace over GPS-RTK in that it tells the pilots where all the other aircraft are rather than simply being more precise about where their own aircraft is.

It is clear that the helicopter crew not knowing where the passenger jet was was the primary cause of the collision.

Arguments about the error in the altimeter readings are suitable to emphasize that depending on them in a crowded airspace is a fool's choice and should have been spotted a long time ago as insufficient to provide clearance.

With respect to the Army aviation helicopter unit, and the other VIP transport helicopters in the National Capital Region, the reason stated for not using ADS-B is that these missions include continuity of government functions, which is significantly more critical than day-to-day transport of very high-level officials (as important as that transport may be).

Law enforcement and med-evac helicopter flights also are involved in the DCA airspace problem. Further, besides the Army unit, reference was made - if I understood correctly - to a unit of USAF. Perhaps this was a reference to the helicopter unit assigned specifically to the White House and was left unclear on purpose.

TCAS gave a TA just prior to that, why should TCAS have lost track?
That's why I don't understand all the fuzz about ADS-B in the UH60. TCAS in the CRJ worked as designed, including RA inhibit down low.
the CRJ crew getting a visual on the UH60 some seconds earlier could have saved them as well, one of many items on the 'could have saved them' list.


I've wondered a couple of times, what if.... the CRJ crew had failed to spot the UH60 all together. Now a left-banking evasive manoeuver was started, and only the left wing was substantially shredded by the rotor.
If they would has kept wings level, maybe both wings would have narrowly escaped major damage, only MLG and belly at risk of the main rotor.
But it all doesn't matter, really. 'Fate is the hunter' and they got caught.

Just went ,very selectively of course, through the thousand of pages of to the dockets and they give a clearer picture , to me at least . of the huge normalization of deviance that took place from both the DCA control staff and the RAT pilots.. I went mainly thought the interviews and the TCAS dockets.
What I learned:
Interestingly the Local controller involved was also a CPL pilot
Pressure to use 33 for landing during high departure rates was there to avoid the queue blocking the taxi ways for arriving aircraft : ( my comment : when you get to that situation traffic should be reduced by departure slots , that what we do in Europe with the Network manager CTOTs..)
No reaction to Conflict alert because visual acquisition was prioritized , i.e if you saw the helicopter passing behind you disregarded the CA. and this was almost always the case so CA with helicopters became disregarded
Advanced training was poor or non existent ( e.g Threat/Error management training).
On the PAT pilots interviews the most flagrant normalization of deviance is requesting visual separation with an aircraft you do not see ( yet) I realize that was declared by pilots other that the one operating that flight , but gives a good indication of the local " best practices " in that area.
Finally on the TCAS issue, one of the screenshots shows other traffic, and we can see that there were 2 TAs one in front -2 and one behind +6 , that could ( emphasis on could) have been one of the reason the CRJ crew missed the urgency of the -2 , but also probably were more focusing on the PAPI so both looking outside instead of at the display .

And to reply to a question earlier by DIBO on the discussion about ADS-B out not avail on the RAT, and its relevance for TCAS, well it would have influenced the degree of accuracy of the Tau calculation ( with Alt returns every 25 ft instead of 100 feet) and could ( again emphasis on could) have changed the alert logic/timing of the TA. Non installation of ADS-B and flying 70 ft too high are probably one of the points the lawyers are going to get into to prove negligence from the military to get more money for their clients , possibly shadowing the real causes. ; which for me are still the design of the procedure and routes, and the failure of the Regulator to act on the alerts. . Love to hear Willow-Run 6-3 comment on this .
.

I appreciate the invitation to comment. With first acknowledging there are several technical factors involved here as to which I have limited understanding (and also that I've commented several times on legal issues likely to be presented by the accident regardless), the legal picture probably is best understood if it is described in two contexts. The fact that the most clearly responsible entities - the Army and the FAA - are both parts of the federal government means that sovereign immunity must be taken into account. (Sikorski, mentioned as a potential defendant by one of the attorneys involved in the case already, has no significant legal risk here, in my view. The reason is its protection by a judicial doctrine known as the "military contractor defense." The specifications given to Sikorski for its design and manufacture were reasonably precise and it met them. See Boyle v. United Technologies Corp. (1989), if more depth and detail is desired.)

As for the airline, to fault the pilots when they were on short finals and expected to concentrate on flying - as others have expressed here numerous times - seems very ill-founded. Whether the airline company could be alleged to have responsibility for not having spoken up more effectively to cause the airspace design and procedure to be redone also strikes me as far too oblivious to the actual operation of the NAS, and the FAA and Congressional processes, to have any validity as an approach to liability. The airline and even Sikorski could still be named as defendants but, to reiterate, this would be just for leverage and not because there is any real pathway to liability for either one.

That having been set as background, the first context ignores the existence of sovereign immunity issues and looks just at what happened and who was responsible. As a rubric for this, "normalization of deviance" seems very accurate. This includes the fact that over time, ignoring Conflict Alerts came to be routine. It includes the practice of confirming "traffic in sight" or related proper terminology, for visual separation even though no traffic had been sighted yet - because it had become routine that the traffic would come into view and be properly identified as the traffic ATC had called out. The testimony about "just make it work", as I heard it, similarly was very concerning; iirc an overall very credible FAA witness acknowledged that the "just make it work" attitude also resulted in decreased safety margins. As did the medical helicopter operator who also had Army helicopter service background. Add in the lack of advanced training, and though I have not practiced law as legal counsel for accident victims' families, the liability theories here appear strong.

Then factor in the use of 3-3 to allievate congestion from high departure rates, rather than slowing or reducing departure slots. Part of the pressure to use 3-3 (as I understood the testimony) was that the Potomac Tracon wanted to increase in-trail separation but DCA instead increased use of 3-3. This was consistent with the attitude, "just make it work".

As to ADS-B on the helicopters, my understanding is that given the roles and missions of the helicopter operations, ADS-B is not equippage the military and its civilian control (in the sense of oversight) could have approved consistent with those roles and missions generally, and especially the continuing-of-government function.

Putting all the causal factors together into a "theory of the case" is perhaps better left to advocates for the accident victims' families (just as defense theories better left to defense counsel in this matter). But since you've impliedly asked, I would not - in this first context - parse out three of the four factors you noted, the lack of ADS-B being the one left out. That leaves the helicopter operating approximately 70 feet too high, the airspace design and procedures including the helicopter routes, and the inaction following the several safety alerts in databases and other reporting functions prior to the occurence of the accident. And including the forced enlistment of DCA for handling more traffic than the widely accepted airspace utilization and safe operation rules and procedures would allow - but they "just made it work." In other words, all of these three factors combine into the most likely theory of liability.

There is a second context, however. Federal government defendants are protected, despite the broad removal (waiver) of sovereign immunity by federal statute, from liability if the alleged negligence resulted from the exercise of discretion. If the actions or omissions being challenged resulted from decisions in which the federal entity weighed economic, social, political and other factors against each other in a form of "policy" decision-making, sovereign immunity remains in place. You can see where this is leading, of course. At what point does the over-use of DCA move out of the protection of "discretionary functions and decision-making" and into the realm of ... just plain negiligence which needs to be addressed in a court action. And likewise, at what point does the Army's set of decisions about how the routes are flown, and how visual separation and traffic sightings are handled, move out of the protection given by discretionary decisions and into the realm of significant negligence not deserving of such protection? Same question for FAA - surely the presence of safety concerns in databases and reporting systems - as unorganized as they may be and as lacking in systematic review as they may be - are matters within the FAA's discretionary functions and decision-making . . . until they're not. (And not equipping PAT helicopters or other D.C.-based Very Important air transport operations by helicopter with ADS-B would have no chance of being ruled not resulting from a discretionary function and decision - it's not even arguable imo.)

I almost included with this (already lengthy) post the "syllabus" of the U.S. Supreme Court's decision in the United States v. Varig Airlines case, which I think is the most pertinent aviation case in which the discretionary function rule is fundamentally involved....but this isn't a legal forum. Still, the U.S. S. Ct. opinion (467 U.S. 797 1984) gives me uncertainty about how any court of competent jurisdiction will draw the line between what would in a case against a not-federal defendant definitely appear to be negligence, and the actions and omissions of the federal defendants here. (My personal view is that the federal defendants acted with such severe negligence that the discretionary function protection has been lost - but that is a gut reaction to the "this accident never should have happened" idea and not legal analysis.)

Finally and last for a reason, I am not commenting about the motives of legal counsel who are representing or advising clients involved in this matter. I have not practiced law a single day, or a single billable hour, or otherwise, on behalf of the families or representatives of aviation accident victims, or the defendants in such matters. As a result, in participation as a guest on this forum I think it's much wiser to let the members of the bar who do have clients and who do practice in this area let their conduct in their professional capacities speak for itself.

Published by Flight Global, August 8 (quoted with any changes)

DOT inspector launches probe into FAA\x92s Washington DC airspace management

The US Department of Transportation\x92s top inspector has launched an investigation into the Federal Aviation Administration\x92s management of airspace near Washington, DC.

The investigation will focus on the agency\x92s design of the airspace and its process of granting military exemptions to a requirement that aircraft use Automatic Dependent Surveillance-Broadcast (ADS-B) systems.

The review, disclosed by the DOT\x92s Office of Inspector General on 8 August, comes amid scrutiny over the FAA\x92s operations \x96 a response to the 29 January midair collision involving a US Army Sikorsky UH-60L Black Hawk helicopter and a PSA Airlines MHIRJ CRJ700 regional jet.

The helicopter had not been transmitting ASB-B \x93Out\x94 information when, flying higher than permitted, it collided with the CRJ700, which was moments from landing at Ronald Reagan Washington National airport, the National Transportation Safety Board has said.

Both aircraft plummeted into the Potomac River, killing all 65 people on the regional jet and all three on the Black Hawk. The Black Hawk had been operating a pilot training flight.


\x93We are initiating this audit to review FAA\x92s oversight of existing safety gaps in the management of DCA\x92s airspace, including the exemption process for ADS-B Out,\x94 says the DOT inspector\x92s office. \x93Our audit objectives are to assess FAA\x92s oversight and management of the airspace surrounding DCA, and policies and procedures to oversee ADS-B Out exemptions.\x94

The office intends to begin the audit this month.

The investigation comes at the request of two senators who asked the inspector general \x93to review a wide-ranging set of safety issues surrounding the accident\x94, the DOT office adds.

The FAA has since 2020 required aircraft have and use ADS-B Out, a system that transmits an aircraft\x92s position and other information about is flight to air traffic controllers. Aircraft equipped with ADS-B \x93In\x94 \x96 which the FAA does not mandate \x96 also receive the position reports. The ADS-B system is intended to give controllers and pilots more information about air traffic, helping prevent collisions.

Under a compromise with military and government aircraft operators, the FAA permits government aircraft operating \x93sensitive\x94 missions to be exempt from the ADS-B Out requirement. It has allowed those operators to define which missions are sensitive.

The US Army has used that exemption extensively when flying helicopters in the Washington, DC region.

On 29 July, senator Ted Cruz introduced a bill that if passed would prohibit government training flights from qualifying for the exemption. It would also require that all aircraft, within five years, have and use ADS-B In.

From Senate Commerce Committee website, following is a summary of the ROTOR Act - Rotorcraft Operations Transparency and Oversight Reform Act. Commerce Committee vote may take place next week.
___________
Rotor Operations Transparency and Oversight Reform (ROTOR) Act
Upgrading In-Flight Safety Technology and Fixing Helicopter Operations to Eliminate Risk
[Sponsors] Senators Ted Cruz (R-TX), Jerry Moran (R-KS), Marsha Blackburn (R-TN), Ted Budd (R-NC), Shelley Moore Capito (R-WV), Roger Marshall (R-KS), Eric Schmitt (R-MO), Tim Sheehy (R-MT), Todd Young (R-IN)

The Problem : The midair collision between American Airlines Flight 5342 and an Army Black Hawk helicopter on January 29th was preventable. For decades, the airspace around the Ronald Reagan Washington National Airport (DCA) operated without an accident, but with thousands of close calls that should have resulted in preventive action. The Black Hawk was likely operating in congested airspace without transmitting Automatic Dependent Surveillance Broadcast (ADS-B) Out\x97a satellite beacon technology that can transmit location, altitude, and velocity to air traffic control and other nearby aircraft faster than radar or other transponders. The airspace is only as safe as its least equipped aircraft, which is why military aircraft must not play by different rules.

The Solution: The ROTOR Act
The ROTOR Act improves aviation safety, addresses FAA knowledge and oversight of ADS-B, and directs the Army Inspector General (OIG) to reevaluate its aviation safety practices. The bill requires:
1. All aircraft operators to equip with ADS-B In technology and transmit such information. ADS-B In is a technology for aircraft to receive location signals from other nearby aircraft and ground technology, improving safety in the sky and on runways.
2. Closes Federal Aviation Administration (FAA) loophole that permitted the Army Black Hawk to fly without broadcasting ADS-B Out. The ROTOR Act allows the FAA to only grant exceptions for \x93sensitive government missions,\x94 not training flights.
3. Requires the FAA to review helicopter routes near airports. The FAA would comprehensively evaluate the airspace at congested airports\x97where helicopters and airplanes are flying near each other\x97nationwide.
4. Directs the Army OIG to initiate a safety coordination audit. The Army Inspector General has declined to voluntarily review the Army\x92s aviation safety practices. The Inspector General would conduct an independent review of the Army's approach to safety.
5. Initiates FAA study on dynamic restricted area for helicopters near airports. The FAA would review whether audio and visual signals could be deployed to reduce airspace confusion and avoid traffic conflicts.
6. Repeals a Fiscal Year 2019 NDAA provision that exempted the Department of Defense from enacted ADS-B transmission requirements.

Why This Matters: The tragic midair collision earlier this year exposed serious and systemic weaknesses in how civilian and military aircraft share and operate in congested airspace. While the National Transportation Safety Board (NTSB) investigation continues, initial findings show glaring failures in oversight and coordination that must be addressed now, not later. The ROTOR Act was drafted in direct response to the operational shortcomings that led to the midair collision. Deconflicting congested airspace and establishing better communication standards between civilian and military aircraftis not optional\x97it is essential. The ROTOR Act does exactly that, ensuring American skies remain the safest in the world.

What load of codswallop. Now we'll have every dogsbody pilot peering at their ADS-B In screens and asking ATC "is that return going to miss us?". TCAS does not require ADS-B, only a transponder (Mode S best). ADS-B In in busy CTAs/zones will be a distracting nightmare for crews.

Every pax jet is separated by SIDs and STARs, with either lateral and/or vertical separation. That is what is required here with the choppers. Playing TCAS dodgem-cars below 1000ft when you're trying to land is not the way to go.

Point 3 is the only one that makes any real sense. The rest sound good only to the great-unwashed.