Vertical Separation Page: 3 of 4

Someone Somewhere
February 07, 2025, 17:07:00 GMT
permalink Post: 11823784

Quote:

Originally Posted by moosepileit

Hence the issue requiring metering the helicopters on the numbered Routes.

I don't suggest a hard 1.5NM, but anywhere standard fixed wing ops cannot assure 500' vertical separation, Rotary wing traffic must be gated and controlled.

If rotary wing mission dictates, then fixed wing traffic will have to wait/go missed/discontinue approach. Visual Sep, ATC and a Pavlovian environment killed an airliner.

Yeah, 1.5Nm is a pretty broad flat rule but I could see an argument for tighter separation particularly where the aircraft is established on an ILS and the helicopter has a fixed obvious route. I don't think holding the helicopter at Hains Point while an aircraft does a visual approach to 33 is sensible, but it might be reasonable for an ILS into 1.

I'm still going to argue that a helicopter on Route 4 from DCA to the Wilson Bridge or across Route 6 is unacceptable while there's an approaching aircraft below 700ft.

Subjects ATC DCA Route 4 Separation (ALL) Vertical Separation

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West Coast
February 07, 2025, 18:22:00 GMT
permalink Post: 11823829

Quote:

Originally Posted by Someone Somewhere

Radar can absolutely fly two planes directly into each other. You have to put a number on how far apart they should be. If you call it "controller's judgement" then all you've done is change who's responsible, given that aircraft are never going to stick exactly to their assigned altitude and heading, and neither radar nor ADS-B gives exactly accurate positions, speeds, or headings.

This page, section "Separation minima based on ATS surveillance systems" quotes ICAO as saying that even in terminal space with good radar, separation should not go below 1,000ft vertically or 3Nm (2.5Nm if established on the same final approach in sequence within 10Nm of the runway). We're already blithely discussing half those standards as being impossible to meet.

Trying to understand the point you\x92re pushing. Are you of the belief that in terminal airspace (Class B in this case) that some minimum lateral or vertical separation standard must be applied? Apologies if I\x92m off base.

Subjects ADSB (All) ICAO Radar Separation (ALL) Vertical Separation

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DIBO
February 11, 2025, 13:27:00 GMT
permalink Post: 11826087

Quote:

Originally Posted by SLFstu

Everything above 200 feet was their airspace.

as indicated by several others (but without formal proof ufn) the Route4 / RWY33 APP combination was never designed to give any vertical separation nor protection. So "their airspace" (=CRJ's) was the normal approach sector/path for a RWY 33 approach, without any relation to the 200ft max (recommended?) on the Heli route

Quote:

Originally Posted by SLFstu

Otherwise according to your graphic even at 200 feet max elevation, being that distance from the east bank any helicopter not maintaining visual separation could collide if an AC was still positioning itself from being low on the glideslope .

my underline could well be the correct conclusion, hence the "no vertical protection" of the route design

Subjects Separation (ALL) Vertical Separation Visual Separation

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ATC Watcher
February 12, 2025, 16:42:00 GMT
permalink Post: 11826805

Quote:

Originally Posted by bill fly

Hi, ATC Watcher,
I am sorry you see a witch hunt in my post. It was supposed to be an idea for a future improvement, rather than a criticism of the very hard worked man who was on the job. On the flying end, there is quite a rigid procedure to follow if a TCAS RA goes off. From posts since I see, that there seems to be one for for STCA triggers too. It seems to me that the gravity of the situation is brought faster to a pilot's attention if the Conflict warning is announced on the RT.
That is just one factor in this sad affair of course. Both TCAS and STCA are last ditch saviours but only if full attention can be paid to them.

Hi Bill , understood, I was a bit too harsh maybe, but I get upset to continuously read what the controller should have done. Remember he was trained like this , to follow procedures that were basically unsafe in order to move the traffic . I can say unsafe because they were removed immediately after the accident , not waiting for the NTSB to recommend it . No everyone is stupid in the FAA , they knew this route was in conflict with 33 Visual arrivals. And did not pass any safety case, but the procedure was kept , most probably due political or military pressures , relying on controllers and pilots to mitigate the risks.

Now on the Conflict alert on the BRITE display . I have no first hand info on the SOPs in DCA on how a TWR controller uses the BRITE and if STCA are even displayed . `, but if they are, seen the charts and the routes , I guess STCA alerts are very common .especially when you delegate separation and you then play with a couple of hundred feet, vertical separation Too many unnecessary alerts equals normalization of deviance, . Look at the Haneda preliminary report , same ..

Finally since you mention TCAS RAs , there is a major difference with STCA , it is not the same as a TCAS RA . With an RA , as a pilot you have to react and follow , it is mandatory , for a controller a STCA is just an alert , just like a TCAS TA , if in your judgement it will pass you will not do anything , and if you have already issued a correcting instruction ( heading, level , etc,,) or here delegate visual separation , the STCA just becomes a nuisance. .

I sincerely hope the DC Controller will not be made the scapegoat of this accident . Not so sure it will not.

Subjects ATC DCA FAA NTSB Preliminary Report Separation (ALL) TCAS (All) TCAS RA Vertical Separation Visual Separation

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PJ2
February 12, 2025, 19:46:00 GMT
permalink Post: 11826918

Quote:

Originally Posted by ATC Watcher

Concur. Scapegoating stochastically guarantees a repeat incident/accident of the same kind under "rhyming" circumstances.

Rarely does the "bad apple" theory of accident causation survive the scrutiny of a robust, honest investigation.

Last edited by Senior Pilot; 12th February 2025 at 23:14 . Reason: Quote was unreadable

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Lonewolf_50
February 14, 2025, 21:10:00 GMT
permalink Post: 11828211

Quote:

Originally Posted by gevans35

Are they suggesting that 100' vertical separation would have been okay?

No, hence the tower telling the Blackhawk to pass behind.

Quote:

Originally Posted by EXDAC

Landing flap, 9 deg pitch up, and full up elevator! That is what I heard NTSB report at today's briefing.
No one in the assembled press made any comment and so likely no one understood that was not normal or what it most likely indicated.

Seems to me like a reaction to seeing the Blackhawk right before impact and a reflex/reaction with intent to avoid.

The subtext for me is that the Blackhawk crew never saw them...but there's more for the NTSB to sort out, as the lady was VERY CLEAR about.

Subjects Blackhawk (H-60) NTSB Pass Behind Pass Behind (All) Separation (ALL) Vertical Separation

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HaroldC
February 16, 2025, 04:57:00 GMT
permalink Post: 11828979

Quote:

Originally Posted by ATC Watcher

I agree that the DC controllers should not be scapegoated. At the same time, the concept of professionalism must be addressed. The concept that professionals in a field must alone (without management, without lawyers, without the public) maintain the best practices of the given professional discipline.

In the US, physicians who work for "Health Maintenance Organizations" are asked to practice medicine, at times, in a "basically unsafe" manner...to keep patients moving. On occasion, such practices will bite a patient (and sometimes the physician). As a whole, HMO physicians do not enjoy the best reputation.

From my perspective, there is practically no difference between the plight of an American air traffic controller and an American HMO physician. Both are expected to "squeeze one more in." Both fields are staffed by above-average capable individuals who thrive on challenges. Both are managed in such a manner that they cannot say "no" and also keep their job. In this regard, at least physicians have job portability.

But the take home point is that one cannot admit to knowing a practice is fundamentally unsafe, yet do it anyway. The public, rightfully, should not accept this. I have no solution except more staff and/or more airports (and not some next-gen whizzbang computer system).

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Easy Street
February 16, 2025, 18:30:00 GMT
permalink Post: 11829380

Quote:

Originally Posted by Not_apilots_starfish

Not quite sure why you all are being relaxed about the air space.

200 feet is the maximum and they had to get permission for this route. They\x92re flying past a busy airport. On one hand you\x92re all saying this accident was bound to happen, on the other hand this in and of itself indicates pilots don\x92t fly through these zones without concerns & vigilance. It makes no sense they would play roulette with the height - most pilots would be adhering to rules & a little on edge knowing a VIP or any number of emergency protocols could happen in the capital of America.

It just doesn\x92t add up - the complacency over elevation. Between two pilots it should have been rectified. May they rest in peace & this isn\x92t a slur against their name but in support of it not being their fault and something amiss.

The point is that PAT25 could have been tightly hugging the eastern bank at precisely 200 feet, and yet everyone would still have died if the CRJ had been slightly below its proper approach path (as it might easily have been). Yes, you can say that *this* accident wouldn't have happened if the helo had been at 200 feet, but that gets us precisely nowhere in preventing recurrence.

Systems that rely on human perfection are 100% guaranteed to fail. The only question is how often. The system in place at DCA required helo pilots to assume responsibility for visual (*not vertical*) avoidance of collisions in order to fulfil their ordered missions. Given what we know about human visual performance at night, that would eventually end badly, and sure enough it did. There is a strong element of the pilots having been set up to fail, which is why no-one here is going hard on them.

Altimetry and height keeping would be important matters for investigators if the collision had occurred due to a breakdown in vertical separation, which as a minimum would involve 500 feet (and more often 1000 feet) of planned spacing to account for instrument and height keeping errors. FAA instrument rating standards require pilots to be able to maintain altitude plus or minus 100 feet. This helicopter was being flown VFR at very low height, which means that looking outside takes primacy over monitoring instruments. I'm sure helo pilots could fly along at 175ft plus or minus 25ft if they really tried, but you can be certain they wouldn't be looking out for traffic (as is required when holding responsibility for visual separation).

However, as there was no vertical separation built into this procedure, all of this is at best a distraction. The more important questions are why procedural barriers were not in place to stop the route being used during landings on runway 33, and whether visual separation at night is an adequate barrier to collision when airliners and their human cargo are involved.

Last edited by Easy Street; 16th February 2025 at 18:57 .

Subjects CRJ DCA FAA PAT25 Separation (ALL) VFR Vertical Separation Visual Separation

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island_airphoto
February 16, 2025, 18:49:00 GMT
permalink Post: 11829389

Quote:

Originally Posted by Easy Street

The point is that PAT25 could have been tightly hugging the eastern bank at precisely 200 feet, and yet everyone would still have died if the CRJ had been slightly below its proper approach path (as it might easily have been). Yes, you can say that *this* accident wouldn't have happened if the helo had been at 200 feet, but that gets us precisely nowhere in preventing recurrence. Systems that rely on human perfection are 100% guaranteed to fail. The only question is how often.

Altimetry and height keeping would be important matters for investigators if the collision had occurred due to a breakdown in vertical separation, which as a minimum would involve 500 feet (and more often 1000 feet) of planned spacing to account for instrument and height keeping errors. FAA instrument rating standards require pilots to be able to maintain altitude plus or minus 100 feet. This helicopter was being flown VFR at very low height, which means that looking outside takes primacy over monitoring instruments. I'm sure helo pilots could fly along at 175ft plus or minus 25ft if they really tried, but you can be certain they wouldn't be looking out for traffic (as required when taking visual separation).

However, as there was no vertical separation built into this procedure, all of this is at best a distraction. The more important questions are why procedural barriers were not in place to stop the route being used during landings on runway 33, and whether visual separation at night is an adequate barrier to collision when airliners and their human cargo are involved.

N123, join the downwind, your traffic is a 737 on final 2 miles out, turn base behind him, you are #2. I can do that at night unless there are other 737s lined up and then I have to figure out which one.
N123, do you see the closest plane lined up, pass right below and behind him and never mind all the other planes right behind. Ah......NO.
There is night visual and there is night nutty visual. The first example leaves a lot of room for error and time for ATC to see if it is going wrong.

Subjects ATC CRJ FAA PAT25 Pass Behind Pass Behind (All) Separation (ALL) VFR Vertical Separation Visual Separation

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WillowRun 6-3
February 16, 2025, 22:06:00 GMT
permalink Post: 11829489

Easy Street:
"However, as there was no vertical separation built into this procedure, all of this is at best a distraction. The more important questions are why procedural barriers were not in place to stop the route being used during landings on runway 33, and whether visual separation at night is an adequate barrier to collision when airliners and their human cargo are involved."

Aircraft accidents bring lawsuits - like it or not.

I'm not a member now, nor have I been a member, of the part of the profession which specializes in suing usually anybody plausible as a defendant. That doesn't mean, as an attorney first and SLF second, I don't see big problems looming ahead. (A prior post on legal factors was junked by the mods, but that was then, this is. . . .)

The FAA and the U.S. Army are privileged with sovereign immunity, as a general rule. A federal statute - the Federal Tort Claims Act - enacted a waiver of sovereign immunity BUT with an important exception. If the allegedly negligent act (or omission) was taken (or failed to be taken) as part of a "discretionary function", immunity still exists. The basic explanation is that discretionary functions involve policy judgments which, in the view of Congress, cannot be "second-guessed" in lawsuits over alleged federal agency negligence. The other half of the equation is that immunity is waived for "ministerial" actions, sort of (to over-simplify) plug-and-chug activities.

Is the construction and operation of the airspace around DCA a matter of policy judgment? I can almost hear the lawyers planning to file suit arguing that airspace rules which make simple, obvious sense are not derived from policy judgments. I can almost hear them issuing subpoenas (through the necessary international process) of Network Manager or MUAC senior managers to gain testimony that in European airspace, as others have observed about Heathrow, the airspace rules are more like "plug-and-chug" than the sometimes esoteric, and usually vague and/or ambiguous, factors which inform the choices made in - offensive phrase coming - "the policy world."

And will our fine feathered legal eagles sue American too, just to go after the deep pocket, and try to force the airline to take a position on the federal immunity questions?

It's too bad so much attention is focused on the dumb shows and noise currently meant to entertain the grandstands (if you get my meaning). There should be a way to compensate the families of the people who perished in this awful, tragic, and ultimately senseless midair collision. Is the United States civil justice system really going back to 1960 and pretending that what we are dealing with is the December 16 1960 DC-8 - L-1049 Super Constellation midair?

As another poster way, way upthread said, I feel rage.

Subjects DCA FAA Separation (ALL) Vertical Separation Visual Separation

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Wide Mouth Frog
February 17, 2025, 00:49:00 GMT
permalink Post: 11829561

Quote:

Originally Posted by WillowRun 6-3

You should feel rage. Managing control of airspace is not a matter of political interest any more than the rules of the road for driving cars is. And in my previous tirade I forgot the earliest parts of this ****show which was an aircraft on a stabilised approach asked to circle to a lesser equipped runway in order to expedite traffic. The next time I hear someone in authority say that safety is our number one concern, I think I'll probably choke on my own vomit.

Subjects DCA FAA Separation (ALL) Vertical Separation Visual Separation

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9 lives
February 17, 2025, 02:39:00 GMT
permalink Post: 11829597

On rare occasion (for my civilian flying) I have been given a VFR clearance at an unusually low altitude (flying along Miami Beach being one example), and occasionally a routing I consider more risky (over water or a built up area with no where to go if the engine quits). Usually, I have accepted and flown the cleared routing, though there have been times I have requested a variation to reduce risk. These have been occasional for me, therefore I treated them as such, and my awareness went up considerably. To me, a situation which deviates from my "normal" requires heightened vigilance I'm a little nervous doing something I would not normally do.

So if the Blackhawk pilots either flew this low altitude route regularly, or it was an operational norm for that pilot group/operation, pilots would begin to relax with it - it's "normal" I opine that it is never normal to fly at 200 feet AGL in a built up area, nor close to the approach path for a busy airport. So if the training and operational norms of this routing lead pilots to think it is normal, they treat it that way, and vigilance goes down. This was an accident waiting to happen, because of normalization of deviance form established norms of flying.

I've learned the hard way that when ATC asks if you have X aircraft in sight, once you think you do, mentally map the path of that aircraft, then start looking for the one you have not seen yet - particularly with two pilots! You get a clearance to pass at 200 AGL under the approach path of a busy airport at night - that's unusual, and spidy senses should be tingling lots! This hyper awareness should be being trained into the operation - a preflight briefing from the lead "On this flight, we could expect this routing and clearance. This will be unusual, and we're going to be extra aware by doing the following....".

So it's easy to blame the Blackhawk pilots, and yes, they wear some of this, but the military let the pilots down by not categorizing this flight as "high risk", and ATC let the pilots down by clearing a routing which had the potential to provide only a hundreds of feet vertical separation, rather than insisting on both vertical, lateral, and projected path separation, and thereafter, telling the Blackhawk pilots all of the airplanes they should be seeing, not just the one, which seems to have been misunderstood.

I have been instructed to orbit to allow for a passing aircraft to clear in front of me, why not this time? Maybe that low altitude air route is too small for a normal orbit? Another red lag about that route not being a good idea!

Subjects ATC Accident Waiting to Happen Blackhawk (H-60) Separation (ALL) VFR Vertical Separation

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meleagertoo
February 20, 2025, 08:54:00 GMT
permalink Post: 11832026

For Heaven's sake! Altitude, altitude, altitude QNH QNH QNH!

A published glideslope (usually nowadays defined by ILS or GPS) is predicated on HEIGHT above the touchdown point , ie it is a physically fixed plane referenced to the ground. How the altimeter is set is completely irrelevant to an aircraft on the glideslope from that point of view. But this aeroplane was on a visual aproach so altimetry is also irrelevant as it is not constrained by a rigidly defined instrumented glideslope.
While the helilane limit is, technically, predicated on an altitude that's really just semantics in this case as it is over water that is at sea level and as any PPL should know that gives height above sea level with QNH set. Thus to all practical intents and purposes the heli routes are flown at heights, and as the rad alt is an order of magnitide more accutate than a bar-alt pilots will likely set its bug at 200ft and and such a low level as this where bar-alt inaccuracy is very significant will (or should) fly that, despite having set QNH because that's the requirement. That way both aircraft are on the same plane of reference, ie vs. the ground = height.

The graphic above is surprising illustration of how a lateral error of just 200m puts a helo firmly into the acceptable glideslope parameters and surely demonstrates more clearly than anything else we've seen the insanity, even irresponsibility of the design of this piece of airspace. Mind, get 200m off track in the vicinity of Heathrow, let alone crossing it and you'll be ordered out of the system the way you came in with a telephone number to call...

Still no word on why this route couldn't have been designed with a sensible vertical separation above the f/w flightpath, someone must know.

Subjects QNH Separation (ALL) Vertical Separation

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Easy Street
February 21, 2025, 01:51:00 GMT
permalink Post: 11832665

Quote:

Originally Posted by meleagertoo

Still no word on why this route couldn't have been designed with a sensible vertical separation above the f/w flightpath, someone must know.

I can't see an obvious way of designing a route that crosses over the runway 33 approach that isn't forced to climb ever higher to separate from traffic in the runway 01/19 approach and departure lanes. You'd have to switch to routing below FW traffic at some point, but where?

Also, I suspect the military requirement for the routes means they have to be as weather-proof as possible, meaning as low as possible. The route heights are given as maximum heights to be flown when the ceiling permits, and can be underflown when required for weather unless stated.

Subjects Separation (ALL) Vertical Separation

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safetypee
March 11, 2025, 20:35:00 GMT
permalink Post: 11845640

Quote:

Originally Posted by BFSGrad

NTSB Aviation Investigation Preliminary Report - N709PS, PAT25

From NTSB interim report on DCA aircraft / helicopter collision.

"Near Midair Collision Events at DCA
Review of information gathered from voluntary safety reporting programs along with FAA data regarding encounters between helicopters and commercial aircraft near DCA from 2011 through 2024 indicated that a vast majority of the reported events occurred on approach to landing. Initial analysis found that at least one TCAS resolution advisory (RA) was triggered per month due to proximity to a helicopter. In over half of these instances, the helicopter may have been above the route altitude restriction. Two-thirds of the events occurred at night.

A review of commercial operations (instrument flight rules departures or arrivals) at DCA between October 2021 and December 2024 indicated a total of 944,179 operations. During that time, there were 15,214 occurrences between commercial airplanes and helicopters in which there was a lateral separation distance of less than 1 nm and vertical separation of less than 400 ft. There were 85 recorded events that involved a lateral separation less than 1,500 ft and vertical separation less than 200 ft."

What is seen - reported; and what is dismissed … diminishes the value of reporting.
A system broken: a broken safety management system at the national level.

Subjects DCA FAA NTSB PAT25 Preliminary Report Route Altitude Separation (ALL) TCAS (All) Vertical Separation

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Winterapfel
March 11, 2025, 20:50:00 GMT
permalink Post: 11845648

Quote:

Originally Posted by safetypee

What is seen - reported; and what is dismissed \x85 diminishes the value of reporting.
A system broken: a broken safety management system at the national level.

Normalization of deviance?

Subjects DCA FAA NTSB Route Altitude Separation (ALL) TCAS (All) Vertical Separation

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WillowRun 6-3
March 12, 2025, 01:22:00 GMT
permalink Post: 11845823

Quote:

Originally Posted by safetypee

It won't be the last time I'll think it compulsory to say this about this accident - I'm not trying to provoke the inevitable lawsuits into higher intensity (despite status as simple SLF/attorney).

Almost invariably lawyers as well as law students and professors, when asked to comment about what is taught in law school, recite the truism that "law school teaches you how to think like a lawyer." Problem is, even quite modest experience in and with the realities and pressures of representing clients - i.e., practicing law - dulls the thinking part and intensifies the hustler mentalities, of which there are many variations. I'm noting this because law school actually trains you how to spot the issues. It sometimes is the case that the standard things lawyers think about a given set of issues are not the most relevant and meaningful things.

With that hopefully not grossly pedantic context out of the way..... in previous comments on this thread I've noted that the federal defendants would be expected to assert sovereign immunity.... more technically, that although the Federal Tort Claims Act waives sovereign immunity in general terms, the statute also contains various exceptions - in other words, the exceptions where they apply keep sovereign immunity in place. The exception relevant here is the "discretionary function" exception, which (pardon the attempt at over-simplifying it) keeps the immunity in place if the allegedly negligent act (or omission) resulted from a federal entity's policy decision or choice.

I previously viewed the discretionary function exception is likely imposing a pretty strong barrier against liability of the (probable) federal defendants. However.

However. However, as I write this somewhere in an aviation law practice a mid-level or even junior associate is pounding their computer keyboard, amassing BASED ON THE ISSUES NOW REVEALED an analysis of how the discretionary function exception has never, never ever ever, been imposed to bar liability for alleged negligence roughly and/or reasonably comparable to the record of "encounters" now documented by NTSB Prelim Report. And that record goes back several years . . . but presumably discovery in United States District Court under the Federal Rules of Civil Procedure could easily reach back to even more past years.

Of course, it will be said that ignoring these many encounters was indeed a policy choice, and so the exception does apply, a forum post like this notwithstanding. But that's just the point. The ISSUE here is that there never was a conscious policy directive which the alleged negligence stemmed from. Or stated another way, if I were in the aviation practice imagined above, I'd be running associates ragged to amass the above-mentioned analysis which establishes, among other things, that GROSS NEGLIGENCE by the FAA can never be, and is not as a matter of law, a predicate for applying the discretionary function exception. (For lawyers out there, somewhat akin to prima facie tort.)

By the way, for all the discovery sports fans out there, just think how much fun it will be to run discovery to amass the facts of what actions - meaning by the aircraft in which the RAs were annunciated - were taken as a result of all the RAs as noted by NTSB's Prelim Report.

Subjects Accountability/Liability DCA FAA NTSB Route Altitude Separation (ALL) TCAS (All) TCAS RA Vertical Separation

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BFSGrad
March 29, 2025, 04:09:00 GMT
permalink Post: 11856414

Quote:

Originally Posted by VHOED191006

Ohhhh for f***sake

Wondering if this was support for an Arlington funeral given altitude and flight path. Appears it was a flight of two T-38s as DO61 is tracked continuously but DO63 pops up only briefly in formation with DO61 as the jets pass over Falls Church.

DAL2983 (A319) and DO61 had an altitude separation of about 100 ft and 0.5 nm at closest point of approach with a relative closure rate of 440 kts.

Two interactions just prior to above that may not have generated RAs: RPA4500 (E75L) passed DO61 with no lateral separation and about 1800 ft vertical separation with a relative closure of 540 kts. JIA5308 (CRJ7) passed DO61 with no lateral separation and 1200 ft separation with a relative closure of 475 kts. Unknown where DO63 was with respect to DO61.

Subjects Separation (ALL) TCAS RA Vertical Separation

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RatherBeFlying
April 28, 2025, 17:01:00 GMT
permalink Post: 11874923

"Incompetence" at many levels

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.

Subjects ADSB (All) ADSB In ADSB Out ATC DCA FAA Separation (ALL) Vertical Separation

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missy
April 29, 2025, 03:55:00 GMT
permalink Post: 11875184

Quote:

Originally Posted by RatherBeFlying

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.

Subjects ADSB (All) ADSB In ADSB Out ATC CRJ DCA FAA Radar Separation (ALL) Vertical Separation

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