February 02, 2025, 03:10:00 GMT
permalink Post: 11819482
Yes it's a "big effing problem". But it's a "big effing problem" of the system, not the specific ATC on duty at the time.
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ATC
CRJ
Traffic in Sight
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February 02, 2025, 03:16:00 GMT
permalink Post: 11819484
I agree completely.
It almost seems backwards to me. Late runway changes should only be applied in quiet environments, allowing plenty of room for manoeuvring without separation issues. The same for visual separation, where only one or two aircraft in the area make misidentification of traffic an improbability. Unfortunately the reverse is true. The busier and more congested the airspace, the more likely these procedures are to be used. From a risk identification and management perspective, I just don't see how operating like this can ever have been deemed acceptable.
Again though, it's used because it's the only way to squeeze an extra 1% out of an over burdened system. And worse of all, everyone involved, from pilots to ATC, think they're the worlds best for making it "work".
It almost seems backwards to me. Late runway changes should only be applied in quiet environments, allowing plenty of room for manoeuvring without separation issues. The same for visual separation, where only one or two aircraft in the area make misidentification of traffic an improbability. Unfortunately the reverse is true. The busier and more congested the airspace, the more likely these procedures are to be used. From a risk identification and management perspective, I just don't see how operating like this can ever have been deemed acceptable.
Again though, it's used because it's the only way to squeeze an extra 1% out of an over burdened system. And worse of all, everyone involved, from pilots to ATC, think they're the worlds best for making it "work".
All that said, the plan for DCA, particularly the helicopter ops, were hazardous in the extreme. The Route 4/33 operations is just plain dangerous, nothing less. The politics of DCA are going to drive a band-aid fix is my prediction. Visual separation won\x92t go away. FAA will get crucified over manning. DCA may lose some significant service, if we closed 33 permanently. If I read the NOTAM correctly, closing 4 and 33, the pain will become known, interestingly, I read elsewhere that the helicopter altitudes were raised to 200\x92 in 2023 due to noise complaints.
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ATC
DCA
FAA
Separation (ALL)
Visual Separation
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February 02, 2025, 03:23:00 GMT
permalink Post: 11819488
Of course. So lets assume the readings to be at the outside of the envelope to the benefit of both aircraft, ie, CRJ at 350 (325 +/- 25 as stated by NTSB), and 200 +/- 75 for the helicopter, so 125. That's 225 feet of vertical-only separation. Is that considered acceptable? If not, why did ATC allow it?
The procedures allowed the controller to hand responsibility for separation to the helo pilot, once the helo was instructed to pass behind an aircraft which the helo said it had identified (twice I think?). However, it seems that the helo identified the wrong aircraft. That's hardly surprising when it's night, there's lots of stationary and moving lights around, and one of the apparently stationary lights is in fact bolted to an aircraft with which you're on a collision course.
Subjects
ATC
CRJ
NTSB
Pass Behind
Pass Behind (All)
Separation (ALL)
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February 02, 2025, 03:31:00 GMT
permalink Post: 11819492
I was reading the reaction of some posters, almost certainly Americans, to the Lufthansa SFO incident where they refused a visual approach, on the thread for that incident on this forum and some other aviation forums:
You really cannot expect to operate into a busy US airport with that sort of restriction.
Lufthansa and all their daughter airlines still uses SOPs born in the 60s, it's godawful.
This whole thing is just ignorant on the part of LH. The SFO ATC is busy and can\x92t baby these unnecessary special requests
I get the no visual approaches at night policy but the no visual separation from other aircraft at night is asinine. Keeping visual from other a/c is easier at night cause of all the blinky stuff.
The answer is if Lufthansa are unable to comply with local procedures then SFO should initiate an approach ban on operators who cannot comply or withdraw their operating permit.
There does seem to be a bit of a \x93we do things differently over here because we\x92re (quote/unquote) better pilots\x94 attitude. Maybe this will be a wake up call, but given the reluctance to change culture I doubt it.
You really cannot expect to operate into a busy US airport with that sort of restriction.
Lufthansa and all their daughter airlines still uses SOPs born in the 60s, it's godawful.
This whole thing is just ignorant on the part of LH. The SFO ATC is busy and can\x92t baby these unnecessary special requests
I get the no visual approaches at night policy but the no visual separation from other aircraft at night is asinine. Keeping visual from other a/c is easier at night cause of all the blinky stuff.
The answer is if Lufthansa are unable to comply with local procedures then SFO should initiate an approach ban on operators who cannot comply or withdraw their operating permit.
There does seem to be a bit of a \x93we do things differently over here because we\x92re (quote/unquote) better pilots\x94 attitude. Maybe this will be a wake up call, but given the reluctance to change culture I doubt it.
However this incident is crossing or converging traffic
People outside aviation, such as Donald Trump as quoted, don't understand that the helicopter is not looking straight ahead at the airliner in the centre of its view for several seconds. Other people think that the other moving across the field of view should make it easier to notice.
But neither is true. One possibility that represents a collision risk is the one a bit out to one side that keeps the same relative direction in the view of the other, just getting bigger
From pictures I found, this helicopter type seems to have four vertical bars in the frame of the front screen, two at the edges, two nearer the middle. So it might be possible for a collision risk aircraft to be hidden behind one of these for some time
Subjects
ATC
President Donald Trump
Separation (ALL)
Visual Separation
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February 02, 2025, 03:33:00 GMT
permalink Post: 11819493
I’m not in job of defending the US system, but there needs to be some perspective. The US airspace operates about 40%-50% of all global aviation. Only half of daily flights are air carrier. For lot of reasons outside this discussion, air carriers are the default transport, trains and buses are a tiny fraction of long distance transport. Apply EASA aviation standards and the US network would grind to halt or create huge gaps in service. We’ve gone 16 years without a fatal US carrier major accident, which isn’t different than the rest of the world, especially when the US has a 50% share. Our economy would suffer greatly and passengers revolt at what would required.
All that said, the plan for DCA, particularly the helicopter ops, were hazardous in the extreme. The Route 4/33 operations is just plain dangerous, nothing less. The politics of DCA are going to drive a band-aid fix is my prediction. Visual separation won’t go away. FAA will get crucified over manning. DCA may lose some significant service, if we closed 33 permanently. If I read the NOTAM correctly, closing 4 and 33, the pain will become known, interestingly, I read elsewhere that the helicopter altitudes were raised to 200’ in 2023 due to noise complaints.
All that said, the plan for DCA, particularly the helicopter ops, were hazardous in the extreme. The Route 4/33 operations is just plain dangerous, nothing less. The politics of DCA are going to drive a band-aid fix is my prediction. Visual separation won’t go away. FAA will get crucified over manning. DCA may lose some significant service, if we closed 33 permanently. If I read the NOTAM correctly, closing 4 and 33, the pain will become known, interestingly, I read elsewhere that the helicopter altitudes were raised to 200’ in 2023 due to noise complaints.
And yes, trying to do EU IFR for everything all the time would create some epic traffic jams.
* IMHO they need the dedicated helicopter controller on at ALL times the helicopters are flying and they need to be held for crossing traffic. They also all need ADS-B, no private pilot that wasn't totally skint would be running around with the lack of situational awareness the helos seem to have in an area like that.
Subjects
ADSB (All)
ATC
DCA
FAA
IFR
Separation (ALL)
Situational Awareness
Visual Separation
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February 02, 2025, 03:43:00 GMT
permalink Post: 11819495
That's assuming perfect equipment accuracy. My understanding is that the tolerance of e.g. an IFR altimeter in the USA is 75'. If that's correct, one IF aircraft with a 'legal' altimeter indicating 325' could in fact be at 250' and another IFR aircraft with a 'legal' altimeter indicating 175' could in fact be at ... 250'. I'm hoping that the avionics in the aircraft involved in this terrible tragedy were more accurate than that, but I always exercise caution in taking numbers out of avionics and ATC systems as 'gospel truth' to the foot. The altitudes on RADAR displays don't increase and decrease in 1 foot increments; nor do the outputs of aircraft transponders. RADALT is different.
Subjects
ATC
Barometric Altimeter
Blackhawk (H-60)
CRJ
IFR
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February 02, 2025, 04:02:00 GMT
permalink Post: 11819500
The area is extraordinarily sensitive to noise complaints. I muffed a landing at KVKX just a few miles away after the takeoff curfew and someone called the cops on me for going around and I got a bit annoyed with them and told them they weren't the air police.
And yes, trying to do EU IFR for everything all the time would create some epic traffic jams.
* IMHO they need the dedicated helicopter controller on at ALL times the helicopters are flying and they need to be held for crossing traffic. They also all need ADS-B, no private pilot that wasn't totally skint would be running around with the lack of situational awareness the helos seem to have in an area like that.
And yes, trying to do EU IFR for everything all the time would create some epic traffic jams.
* IMHO they need the dedicated helicopter controller on at ALL times the helicopters are flying and they need to be held for crossing traffic. They also all need ADS-B, no private pilot that wasn't totally skint would be running around with the lack of situational awareness the helos seem to have in an area like that.
Subjects
ADSB (All)
ATC
DCA
IFR
Situational Awareness
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February 02, 2025, 05:47:00 GMT
permalink Post: 11819528
7.2.1 VISUAL SEPARATION
a.2. Pilot-applied visual separation.
(a) Maintain communication with at least one of the aircraft involved and ensure there is an ability to communicate with the other aircraft.
(b) The pilot sees another aircraft and is instructed to maintain visual separation from the aircraft as follows
(1) Tell the pilot about the other aircraft. Include position, direction, type, and, unless it is obvious, the other aircraft's intention.
(2) Obtain acknowledgment from the pilot that the other aircraft is in sight.
(3) Instruct the pilot to maintain visual separation from that aircraft.
a.2. Pilot-applied visual separation.
(a) Maintain communication with at least one of the aircraft involved and ensure there is an ability to communicate with the other aircraft.
(b) The pilot sees another aircraft and is instructed to maintain visual separation from the aircraft as follows
(1) Tell the pilot about the other aircraft. Include position, direction, type, and, unless it is obvious, the other aircraft's intention.
(2) Obtain acknowledgment from the pilot that the other aircraft is in sight.
(3) Instruct the pilot to maintain visual separation from that aircraft.
So that means this collision occurred entirely within all established protocls?
These aircraft crashed, as per the system specifications.
So the system is, to put it plainly...FUBAR?
That's not good.
Subjects
ATC
CRJ
Separation (ALL)
Visual Separation
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February 02, 2025, 05:50:00 GMT
permalink Post: 11819530
That\x92s the kind of information that the NTSB will discover from interviews.
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ATC
CRJ
DCA
NTSB
Separation (ALL)
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February 02, 2025, 06:03:00 GMT
permalink Post: 11819532
Well, that's interesting. You seem to be saying that "the system" worked as designed? FDR notes immediately before your reply:
Did ATC do all of that? Having listened to the ATC comms (including the UHF) a few times, I believe they did, for the most part? They mentioned CRJ (of what use is mentioning the type at night, I have no idea, but they did), they mentioned where it was and where it was headed, and they received two acknowledgments...
So that means this collision occurred entirely within all established protocls?
These aircraft crashed, as per the system specifications.
So the system is, to put it plainly...FUBAR?
That's not good.
Did ATC do all of that? Having listened to the ATC comms (including the UHF) a few times, I believe they did, for the most part? They mentioned CRJ (of what use is mentioning the type at night, I have no idea, but they did), they mentioned where it was and where it was headed, and they received two acknowledgments...
So that means this collision occurred entirely within all established protocls?
These aircraft crashed, as per the system specifications.
So the system is, to put it plainly...FUBAR?
That's not good.
The procedures effectively abdicate separation responsibility to a single point of failure, where failure is not unlikely and, as a consequence of the airspace design, failure results in high probabilities of collision.
The difficulties of identifying a specific aircraft, at night, in a background of stationary and moving lights, when moving objects on a collision course will always appear stationary to each other, are well known, as are the probabilities of mis-identification. The airspace design 'squeezes' inbound aircraft and transiting helicopters to practicality the same altitude, when instrument and other tolerances are taken into consideration.
Subjects
ATC
CRJ
Separation (ALL)
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February 02, 2025, 06:12:00 GMT
permalink Post: 11819533
It's a symptom of a system operating beyond its capacity.
The fact that this sort of procedure is so normalised that many crew don\x92t even see this as a threat is quite telling about the safety culture within the US aviation sector. Someone above mentioned that night circling approaches are not approved in many company Ops Manuals, so ATC issue late visual approaches instead, as a means to work around this limitation. This should be ringing alarm bells to all.
This sort of thing wouldn\x92t even be attempted in most parts of the world, let alone allowed to become normal sop.
Plus the often aggressive and intimidating tone from US ATC, and their habit of simply talking faster and saying everything multiple times (eg say again), has persuaded pilots and controllers that they are "making it work"
Whereas it's a classic example of Normalisation of Deviance
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ATC
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February 02, 2025, 06:15:00 GMT
permalink Post: 11819534
As a system ' - at night - I think it's crazy. But that's the system.
Subjects
ATC
Blackhawk (H-60)
Pass Behind
Pass Behind (All)
Separation (ALL)
Vertical Separation
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February 02, 2025, 07:18:00 GMT
permalink Post: 11819546
I have no doubt that you're right about the generally high level individual skills of U.S. pilots and ATC staff, rather than deficiencies, actually being part of the problem. A slight extension of the Frank Borman adage about superior pilots using their superior skills to get out of dangers that they never should have encountered in the first place, but in so doing, inadvertently masking the erosion of safety margins they confront daily as a result of flawed ATC procedures and political pressure. I know it has become the norm, but where's the union push-back? Perhaps a few days of "down-tools" would restore public and political attention?
Last edited by Max Tow; 2nd February 2025 at 07:45 .
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ATC
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February 02, 2025, 07:24:00 GMT
permalink Post: 11819550
Well, that's interesting. You seem to be saying that "the system" worked as designed? FDR notes immediately before your reply:
Did ATC do all of that? Having listened to the ATC comms (including the UHF) a few times, I believe they did, for the most part? They mentioned CRJ (of what use is mentioning the type at night, I have no idea, but they did), they mentioned where it was and where it was headed, and they received two acknowledgments...
So that means this collision occurred entirely within all established protocls?
These aircraft crashed, as per the system specifications.
So the system is, to put it plainly...FUBAR?
That's not good.
Did ATC do all of that? Having listened to the ATC comms (including the UHF) a few times, I believe they did, for the most part? They mentioned CRJ (of what use is mentioning the type at night, I have no idea, but they did), they mentioned where it was and where it was headed, and they received two acknowledgments...
So that means this collision occurred entirely within all established protocls?
These aircraft crashed, as per the system specifications.
So the system is, to put it plainly...FUBAR?
That's not good.
Musings:
"The system" includes all of us that are involved in aviation at all levels, everyday. Thee are a lot of flights that go into DCA every day, each crew observing the same conditions, and conducting briefings of the arrivals, approaches and departures. Same out of LAX etc. How many of us, as stakeholders in the system have raised our concerns to the system by the means available, the ASRS, company safety reporting systems, the squadron SMS systems. How many safety managers have bothered to go and do an operational route survey/audit? Without our active participation, then we are relying on some person long retired who designed a procedure that survives to this point in time, and due to our collective indifference to the common users safety we remain broadly mute, until something falls off the perch. At this point we feign surprise, shock and some horror, yet, search inside, how many of us are surprised by this event, or Jeju Air in Muan, or the Russians shooting down yet another civil aircraft, Instead, we pontificate, (myself possibly more than most) and point the bone at all others in the system,
SMS systems only work if they have data that is meaningful. Each airline may seem to be swamped in data, that however is not the case for dealing with extremely low incidence, but high consequence events. There is not enough data generally to do a damned thing with, for just UAL, DAL, AAL etc or other operators. To be able to understand fully a system behavior there has to be adequate data, At present the only aggregated data of any note is that with NASA under the ASRS, and with ICAO at the reportable event level. Each ICAO state safety plan is supposed to provide data to the extent it can to its own community and to ICAO, and that is generally the last that is seen of the data. The airlines and operators dont get feedback, ICAO may or may not apply that data towards rule making, but that is years hence, and does not meet the needs of the user or the public today. Without the data being available to all, it is diminished in its utility. SMS systems have limited effectiveness that is IMHO glossed over universally, as actually getting data that is useful takes effort, and then evaluating that data takes critical analysis. By squandering the opportunity to have the data to evaluate, it should be no surprise that occasionally, we have SA-1, SA-2 and SA-3 type situational awareness failures of biblical proportions.
Aerospace suffers from frequent events that are normal in most respects. Functional resonance is a reasonable paradigm to assess how the system is really working, to give the system the understanding of how large the slip between assumptions and real system behavior is. The means of doing that is available from the flight data, and from operational audit aimed at understanding how expectations of process match with the real world.
Alternatively, we can sit back and blame the victims of the most recent mishaps, chasing those that should take responsibility for this, which to an extent falls on all of us that use the system and don't bother to raise concerns to the system.
Complacency works well though, until it doesn't.
Subjects
ATC
CRJ
DCA
ICAO
Situational Awareness
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February 02, 2025, 07:39:00 GMT
permalink Post: 11819561
ATC did do what he is "supposed" to do. The Blackhawk was told to "pass behind". Nothing to do with vertical separation. It's a form of separation. That's how it works. Thousands of times every day, all over the place.
As a system ' - at night - I think it's crazy. But that's the system.
As a system ' - at night - I think it's crazy. But that's the system.
Subjects
ATC
Blackhawk (H-60)
Pass Behind
Pass Behind (All)
Separation (ALL)
Vertical Separation
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February 02, 2025, 07:41:00 GMT
permalink Post: 11819563
This incident follows the same script as decades of others where ATC verifies that a pilot has the (incorrect) traffic in sight and shortly afterward there is a midair.
Subjects
ATC
See and Avoid
Traffic in Sight
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February 02, 2025, 08:41:00 GMT
permalink Post: 11819594
Originally Posted by Lead Balloon
The difficulties of identifying a specific aircraft, at night, in a background of stationary and moving lights, when moving objects on a collision course will always appear stationary to each other , are well known.
I have decided to stay out of this thread (from early on) but what I just read is wrong. If you have ever experienced an aircraft descending 'into' you in a constant curving descent into the cct on a constant aspect you would not make that statement. It has happened to me.
The whole airframe was invisible and appeared as a black void - the only thing alerting me to the fact, was the absence of the background night sky as it grew bigger and bigger in the field of view
I manoeuvred below and behind - it was only then that I could see nav and anti col lights - and even then they were so close they meant nothing
We were about 3 seconds from impact but I had watched that bit of sky for a lot longer - not knowing what I was seeing
The other pilot had absolutely no idea I was there [I was low (under) in his 2 o'clock] - or behind him when he leveled off and rolled wings level to continue down wind
That night I saved our lives - but it was only by luck and good fortune
And yes - I had been passed Traffic Information - which is why I was looking where I was at the time
It is a big sky - but not that big
Over the last few days this mental video has played over and over to me when I think about it
This little story may stick in the memory and save someone else one day
To add: What the controller would have seen - if he had seen anything - was two aircraft deconflicting beautifully, as one joined and the other positioned behind
Last edited by Deep Throat; 2nd February 2025 at 09:03 .
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ATC
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February 02, 2025, 10:30:00 GMT
permalink Post: 11819666
Apply EASA aviation standards and the US network would grind to halt or create huge gaps in service ... Our economy would suffer greatly and passengers revolt at what would required.
... The politics of DCA are going to drive a band-aid fix is my prediction. Visual separation won\x92t go away. FAA will get crucified over manning. DCA may lose some significant service, if we closed 33 permanently.
... The politics of DCA are going to drive a band-aid fix is my prediction. Visual separation won\x92t go away. FAA will get crucified over manning. DCA may lose some significant service, if we closed 33 permanently.
[I think of the Austin investigation, which did not even mention, let alone question the practice of issuing runway clearances to multiple aircraft at the same time, which IMHO is the root cause of most of the recent near misses.]
Last edited by Easy Street; 2nd February 2025 at 10:50 .
Subjects
ATC
Close Calls
DCA
FAA
Separation (ALL)
Visual Separation
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February 02, 2025, 10:36:00 GMT
permalink Post: 11819671
What should have been the vertical separation? I'm just a lowly PPL holder, but I imagine if the CRJ was at 325 feet, even a ceiling of 200 feet is too high for the helicopter.
Not just from a collision perspective, but a wake turbulance issue.
And maybe more importantly, what should have been the horizontal separation? Surely it should have been at least 500 feet after the passing CRJ (not based on air law, just common sense). Clearly there was no horizontal or vertical separation in the end, but just how far off minimums was the helicopter? Seems nearly impossible to be that far off the expected flight path.
Not just from a collision perspective, but a wake turbulance issue.
And maybe more importantly, what should have been the horizontal separation? Surely it should have been at least 500 feet after the passing CRJ (not based on air law, just common sense). Clearly there was no horizontal or vertical separation in the end, but just how far off minimums was the helicopter? Seems nearly impossible to be that far off the expected flight path.
Dozens of posts back, I asked the question that many recent posts have been keying on... if everyone was where they were supposed to be, they would have passed one over the other with 150 feet of separation! In what world is that OK?
Can all these non-aviation pundits here please get it into their heads that just because the helilane has a cieling of 200ft and the glideslope is 325 or whatever it does not imply that helos can, would or might EVER be allowed to pass 125 ft under an aircraft on finals nor would any sane helo pilot (there are some!) do so. That would be insane, as surely this common sense you speak of should tell you? What's a lateral 500ft got to do with air law or anything else, ever? You're muddling completely unconnected and irrelevant matters. Have you not read/heard the ATC transcripts? Helos are not given clearance to and cannot cross until landing traffic is clear (as this helo one was told) - ie until it has passed unless the incoming is sufficiently far away for there to be no possible confliction.
How far off minimums (actually a maximum)? - you've already answered that question yourself. 125ft.
The insanity of this routing procedure is that in the event of an accidental horizontal incursion into the track of an inboud as happened here there is in theory only 125 ft of vertical clearance to prevent a disaster which is nowhere near enough of a safety margin. That route should have been, imho, at least 5-800ft or more above two dots up on the glideslope.
Once again, helicopters never, never ever come to a free air hover for separation purposes - this is a ridiculous concept for numerous reasons that are too long to go into here, and would be downright dangerous at night over a black hole at 200ft. They slow and orbit if they have to, maybe slow right down if wind direction and speed allows, but never hover.
I know not everyone here is experienced on helos but if so could they please refrain from speculating on operating procedures? All this guff about altimeter accuracy is completely irrelevant and has created a huge amount of unnecessaty noise. The aircraft was flying a visual sight-picture approach where an altimeter barely features at all and helos at low level, especially at night and over water do not use the baro altimeter. They exclusively refer to rad-alt.
Finally, all those who think a visual self-positioning clearance as employed in this case behind crossing traffic is somehow hazardous are completely incorrect. Once again, at Heathrow the helilane crosses 27 L and R thresholds at (iirc)1000ft. The only clearances given as you approach the boundary is to the effect of 'cross NOW (directly) over the threshold', 'hold (at a VRP clear N/S of the threshold)' or, having confirmed and read back landing traffic visual and identified the formula is repeated, 'after the landing traffic 2 miles cross behind'. It's perfectly safe as as it isn't done at the same height as the airliner but with a large vertcal clearance too.
btw, does Marine One fly this route?
Last edited by meleagertoo; 2nd February 2025 at 11:41 .
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ATC
CRJ
Hover
Separation (ALL)
Vertical Separation
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February 02, 2025, 10:42:00 GMT
permalink Post: 11819672
I the idea that while the extra airspace capacity afforded by visual separation at night may come at the price of occasional accidents such as this, that price is worth paying for passenger, government and economic benefit. Those kind of ideas don't tend to be well received or understoood by the public, or by extension by elected representatives, so a prediction of my own: every single agency and authority involved will go out of its way to avoid acknowledging that idea, and instead will pretend that visual separation at night is a fundamentally sound practice let down by poor procedure design and/or ATC at DCA.
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ATC
DCA
Separation (ALL)
Visual Separation
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