January 30, 2025, 13:08:00 GMT
permalink Post: 11817221
I am rather surprised by the route the helicopter took, this looks like quite a high risk in itself.
Yes, there is noise abatement and all that, but is there a compelling reason beyond that why the heli had to track the river in opposite direction to the flow of arriving airliners? Certainly, it would have been possible for a controller, radar-equipped or not, to hold the heli east of the field and clear him for a midfield crossing on heading 270 or so as an airliner is just touching down on 33 or 01 and the next one is still a few miles out? That would have kept him well out of the approach sector, allowed for a possible go-around of an arriving airliner and also would not interfere with departing traffic.
Surely, someone familiar with DCA can explain...
Yes, there is noise abatement and all that, but is there a compelling reason beyond that why the heli had to track the river in opposite direction to the flow of arriving airliners? Certainly, it would have been possible for a controller, radar-equipped or not, to hold the heli east of the field and clear him for a midfield crossing on heading 270 or so as an airliner is just touching down on 33 or 01 and the next one is still a few miles out? That would have kept him well out of the approach sector, allowed for a possible go-around of an arriving airliner and also would not interfere with departing traffic.
Surely, someone familiar with DCA can explain...
I would expect the airliner not to have to take any avoiding action, as it\x92d be IFR on a standard arrival for RW33. I would expect ATC to inform them of the helicopter traffic below them on the east side of the river.
I would expect the helicopter traffic to ultimately be responsible for avoidance, and they\x92d I guess be flying \x91Special VFR\x92*. But as they\x92re in controlled airspace then they should have been warned (which apparently they were) about the arriving civil traffic.
If the helicopter was, indeed, following Route 4 then what led to the discrepancy in position & height is conjecture. Also why they confirmed traffic in sight yet still collided is conjecture (& It\x92s possible they had their own emergency)
*) does \x91Special VFR\x92 exist/ apply for \x91night VMC\x92 ops in US controlled airspace ? it\x92s a long time since my FAA/US flying days\x85\x85
Subjects
ATC
DCA
IFR
Route 4
Traffic in Sight
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January 30, 2025, 13:23:00 GMT
permalink Post: 11817231
Im not \x93familiar with DCA\x94 but from the Terminal Chart & discussion here it\x92s clear that the heli was following the transit route 4, which would be a normal activity. Though it\x92s also possible their plan was to leave route 4 & cross the river towards the airfield\x85.
I would expect the airliner not to have to take any avoiding action, as it\x92d be IFR on a standard arrival for RW33. I would expect ATC to inform them of the helicopter traffic below them on the east side of the river.
I would expect the helicopter traffic to ultimately be responsible for avoidance, and they\x92d I guess be flying \x91Special VFR\x92*. But as they\x92re in controlled airspace then they should have been warned (which apparently they were) about the arriving civil traffic.
If the helicopter was, indeed, following Route 4 then what led to the discrepancy in position & height is conjecture. Also why they confirmed traffic in sight yet still collided is conjecture (& It\x92s possible they had their own emergency)
*) does \x91Special VFR\x92 exist/ apply for \x91night VMC\x92 ops in US controlled airspace ? it\x92s a long time since my FAA/US flying days\x85\x85
I would expect the airliner not to have to take any avoiding action, as it\x92d be IFR on a standard arrival for RW33. I would expect ATC to inform them of the helicopter traffic below them on the east side of the river.
I would expect the helicopter traffic to ultimately be responsible for avoidance, and they\x92d I guess be flying \x91Special VFR\x92*. But as they\x92re in controlled airspace then they should have been warned (which apparently they were) about the arriving civil traffic.
If the helicopter was, indeed, following Route 4 then what led to the discrepancy in position & height is conjecture. Also why they confirmed traffic in sight yet still collided is conjecture (& It\x92s possible they had their own emergency)
*) does \x91Special VFR\x92 exist/ apply for \x91night VMC\x92 ops in US controlled airspace ? it\x92s a long time since my FAA/US flying days\x85\x85
Subjects
ATC
DCA
IFR
Route 4
Traffic in Sight
VFR
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January 30, 2025, 14:14:00 GMT
permalink Post: 11817273
I have not read many of the earlier posts, so do not know what has been said about ATC’s involvement & whether the helicopter was operating under IFR but, it would appear that the helicopter was operating under VFR & simply being given traffic information, rather than being IFR & being properly separated from other IFR traffic (the AAL a/c in particular). If so, this accident revives the controversy about whether or not you can safely mix dense IFR traffic & VFR traffic in the same airspace. Without knowing the actual cause of this accident - there may be some other cause - it would seem to suggest that the answer to this question is, “NO, you cannot”. I remember giving traffic information to a departing HS125 , from Aberdeen, about a Cessna 150 operating within its projected flight path at up to 5,000 ft. 6 nm west of the airfield ; & being met with the reply from the 125’s pilot, “what do you expect me to do with that info ?” Thinking about it, he had a point. Simply being informed about prospective traffic does not guarantee, in any way , that you are going to be able to see & avoid it. Countless collisions between (mainly light) a/c since; plus this latest tragedy; would seem to prove the point !
Subjects
IFR
See and Avoid
VFR
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January 30, 2025, 14:37:00 GMT
permalink Post: 11817285
my earlier point related to responsibility for separation\x85. and that the helo would be VFR (if following the low-level transit Route 4) and the airliner IFR. I was unsure if there was a special category for VFR at night\x85
apologies for sowing any confusion\x85\x85
Subjects
ATC
IFR
Route 4
VFR
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January 30, 2025, 15:23:00 GMT
permalink Post: 11817324
Heli route 4 is at or below 200ft if I read the chart correctly.
Approach traffic seems to be approx 400-500ft at this point.
Which turnip decided it would be OK to allow vertical separation of 300ft on a busy approach path? And allow it VFR at night?
This accident was baked in. Bound to happen at some point.
Approach traffic seems to be approx 400-500ft at this point.
Which turnip decided it would be OK to allow vertical separation of 300ft on a busy approach path? And allow it VFR at night?
This accident was baked in. Bound to happen at some point.
In this case, the aircraft was flying an approach to one runway with a circle-to-land on RW-33. Ask any pilot; a circle to land in itself ups the work load. The margin for error of any kind at DCA is small and the 5200 foot runway isn't all that long. Even on a simple landing where none of these considerations are an issue, at some point the pilots reduce their "see and avoid" efforts and concentrate their efforts on achieving the proper line up and glide slope, rate of descent, aircraft configuration, flap setting, etc. etc. etc. In other words, the complicated routine required to safely land an airliner these days is already close to task overload even when things are going well. Add in the fact that it's night time at a very busy airport and looking out the window gets shoved pretty far down the "to do" list. But generally speaking, the system works because big busy airports pretty much operate using IFR rules and nearly all the aircraft are under close control. I other words, even on a crystal clear day under VFR flight conditions, someone is keeping a very close eye on the airliners coming and going from major airports. If a pilot makes a mistake and levels off at the wrong altitude, for example, there is a very good chance a controller will catch that error immediately even on a sunny VFR day. And that's a good thing because truth-be-told, when an airliner is seconds from touch down these days, there isn't much "see and avoid" going on. That's just the way it is.
But apparently DCA routinely has all sorts of helo traffic buzzing around under modified VFR flight rules. The pilots are talking to a controller but without being under the same sort of close control which is usually associated with how airliners operate. And they do that night and day, trusting the helo pilots to not make a mistake. But it looks like someone DID make a mistake last night and nobody caught it in time.
Subjects
ATC
Circle to Land (Deviate to RWY 33)
DCA
FAA
IFR
Route 4
See and Avoid
Separation (ALL)
VFR
Vertical Separation
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January 30, 2025, 15:41:00 GMT
permalink Post: 11817334
When and where I learned to fly (and on each new rating, refresher and check ride) we had to prove that we knew airspace classification. DCA is listed as class B airspace (and special rules on top).
That should apply worldwide, not just in EASA land.
It seems to be a US speciality that ATC can delegate the separation to aircrews (visually) and this at night! And how the hell can ATC separate vertically near the ground when mode S transponders report pressure altitude in steps of 100 feet only?
I dont know the rules of vertical separation by heart but its certainly not less than 500 feet for crossing paths. Is one last digit more or less a separation? This heli crew should have been told by ATC to hold until the aircraft(s) on final have safely passed. It's one of the benefits of a helicopter that it can hover.
Class B.
IFR
and
VFR
flights are permitted, all flights are provided with
air traffic control service
and are separated from each other.
It seems to be a US speciality that ATC can delegate the separation to aircrews (visually) and this at night! And how the hell can ATC separate vertically near the ground when mode S transponders report pressure altitude in steps of 100 feet only?
I dont know the rules of vertical separation by heart but its certainly not less than 500 feet for crossing paths. Is one last digit more or less a separation? This heli crew should have been told by ATC to hold until the aircraft(s) on final have safely passed. It's one of the benefits of a helicopter that it can hover.
Subjects
ATC
DCA
Hover
IFR
Separation (ALL)
VFR
Vertical Separation
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January 30, 2025, 18:16:00 GMT
permalink Post: 11817497
If that published in AIP route 4 crossing under the final approach path of RWY 33 says max 200 ft and according the calculations made by Luc Lion earlier the altitude of the CRJ was, if not exactly on the PAPI , very close to it at 300 Ft in less than a mile before TDZ. But 100 ft separation is not a normal civil vertical separation standard in controlled airspace, for an IFR flight. it is 500 ft minimum in our books. . One of the roots of the problem is right there : a published route where you need a visual military type separation to make it work . And it may have worked hundreds of times before , sometimes with luck I am sure, but this time it did not and this was just an accident waiting to happen written in the book.
To answer an earlier question , Yes they have CISM , NATCA is good at this , they will take care of the controllers.
@ fdr : our posts crossed each other , fully agree with you .
To answer an earlier question , Yes they have CISM , NATCA is good at this , they will take care of the controllers.
@ fdr : our posts crossed each other , fully agree with you .
Subjects
Accident Waiting to Happen
CRJ
IFR
Route 4
Separation (ALL)
Vertical Separation
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January 30, 2025, 22:16:00 GMT
permalink Post: 11817700
See and avoid in airline operations simply does not work. High workload, human factors, visual limitations, high closing speeds simply make it unreliable.
There have been countless similar cases of near misses. Near airports, crossing traffic, especially helicopters is a real issue, as is the totally inappropriate see and avoid principle with commercial traffic. In my view we need a complete rule change and rethink around lack of radar separation between IFR and VFR traffic.
All too frequently ATC allow IFR and VFR far too close on approach and are permitted to just inform the VFR traffic to visually manoeuvre themselves all too close to IFR traffic. The book 'The Naked Pilot' years ago established that see and avoid does not work, simple as that.
Class D airspace whilst not necessarily involved here often causes such issues. Pilot's wrongly believe ATC separates IFR and VFR. Frequently ATC allow conflicts to develop on the basis of law, rather than duty of care. We need to get back to common sense, and that is ATC must stop VFR traffic getting anywhere near airliners on final approach or from crossing the go around track. Either lateral or vertical separation needs to be enforced or repeats of this type of accident will definitely repeat.
Lessons have not been learned previous to this accident. I fear we will see a repeat, and low level near airport ATC separation needs to improve.
We need the industry to wake up and realise, see and avoid is unreliable, and air law does not protect IFR traffic from VFR traffic enough.
There have been countless similar cases of near misses. Near airports, crossing traffic, especially helicopters is a real issue, as is the totally inappropriate see and avoid principle with commercial traffic. In my view we need a complete rule change and rethink around lack of radar separation between IFR and VFR traffic.
All too frequently ATC allow IFR and VFR far too close on approach and are permitted to just inform the VFR traffic to visually manoeuvre themselves all too close to IFR traffic. The book 'The Naked Pilot' years ago established that see and avoid does not work, simple as that.
Class D airspace whilst not necessarily involved here often causes such issues. Pilot's wrongly believe ATC separates IFR and VFR. Frequently ATC allow conflicts to develop on the basis of law, rather than duty of care. We need to get back to common sense, and that is ATC must stop VFR traffic getting anywhere near airliners on final approach or from crossing the go around track. Either lateral or vertical separation needs to be enforced or repeats of this type of accident will definitely repeat.
Lessons have not been learned previous to this accident. I fear we will see a repeat, and low level near airport ATC separation needs to improve.
We need the industry to wake up and realise, see and avoid is unreliable, and air law does not protect IFR traffic from VFR traffic enough.
Subjects
ATC
Close Calls
IFR
Radar
See and Avoid
Separation (ALL)
VFR
Vertical Separation
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January 30, 2025, 22:19:00 GMT
permalink Post: 11817705
The airliner is under IFR rules on its flight plan until it gets changed to a different runway, when it's then VFR.
The chopper is under VFR, stooging along a river at 200 ft and avoiding traffic on approach to Reagan by visual clues alone.
Radar useless as the aircraft are too low.
Airliner TCAS useless as inhibited, even if it can decode the military transponder's data.
Radio situational awareness compromised as chopper on UHF, airliner on VHF. So each aircraft can neither hear the other nor the ATC instructions to that aircraft.
It's difficult to see aircraft at night against a backdrop of a city with thousands of lights. And when you're gonna hit something, as others have said, that light doesn't move relative to you, so you don't notice it - it just blends into the background lights.
It only takes the chopper to misidentify the aircraft it's supposed to go behind and to therefore turn into the path of the airliner it was supposed to avoid - draw the map with the vectors and it all makes sense. These two aircraft ended up in the Potomac, but they could have ended up in much worse places in terms of loss of life on the ground.
Seems to me it's been an accident waiting to happen for some time.
Subjects
ATC
Accident Waiting to Happen
IFR
Pass Behind
Pass Behind (All)
Radar
Situational Awareness
TCAS (All)
VFR
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January 30, 2025, 22:26:00 GMT
permalink Post: 11817707
Subjects
IFR
See and Avoid
VFR
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January 30, 2025, 22:35:00 GMT
permalink Post: 11817716
OK so what's your interpretation of the rules here then?
The airliner is under IFR rules on its flight plan until it gets changed to a different runway, when it's then VFR.
The chopper is under VFR, stooging along a river at 200 ft and avoiding traffic on approach to Reagan by visual clues alone.
Radar useless as the aircraft are too low.
Airliner TCAS useless as inhibited, even if it can decode the military transponder's data.
Radio situational awareness compromised as chopper on UHF, airliner on VHF. So each aircraft can neither hear the other nor the ATC instructions to that aircraft.
It's difficult to see aircraft at night against a backdrop of a city with thousands of lights. And when you're gonna hit something, as others have said, that light doesn't move relative to you, so you don't notice it - it just blends into the background lights.
It only takes the chopper to misidentify the aircraft it's supposed to go behind and to therefore turn into the path of the airliner it was supposed to avoid - draw the map with the vectors and it all makes sense. These two aircraft ended up in the Potomac, but they could have ended up in much worse places in terms of loss of life on the ground.
Seems to me it's been an accident waiting to happen for some time.
The airliner is under IFR rules on its flight plan until it gets changed to a different runway, when it's then VFR.
The chopper is under VFR, stooging along a river at 200 ft and avoiding traffic on approach to Reagan by visual clues alone.
Radar useless as the aircraft are too low.
Airliner TCAS useless as inhibited, even if it can decode the military transponder's data.
Radio situational awareness compromised as chopper on UHF, airliner on VHF. So each aircraft can neither hear the other nor the ATC instructions to that aircraft.
It's difficult to see aircraft at night against a backdrop of a city with thousands of lights. And when you're gonna hit something, as others have said, that light doesn't move relative to you, so you don't notice it - it just blends into the background lights.
It only takes the chopper to misidentify the aircraft it's supposed to go behind and to therefore turn into the path of the airliner it was supposed to avoid - draw the map with the vectors and it all makes sense. These two aircraft ended up in the Potomac, but they could have ended up in much worse places in terms of loss of life on the ground.
Seems to me it's been an accident waiting to happen for some time.
Subjects
ATC
Accident Waiting to Happen
CRJ
IFR
Pass Behind
Pass Behind (All)
Radar
Separation (ALL)
Situational Awareness
TCAS (All)
VFR
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January 30, 2025, 23:01:00 GMT
permalink Post: 11817736
but my understanding was always that the flight rules for the CRJ don't change, unless the crew cancel their IFR plan: ie flying a visual approach doesn't change the flight rule status. The crew can still expect IFR separation from other IFR & SVFR flights, & traffic information on conflicting VFR flights.
Subjects
CRJ
IFR
Separation (ALL)
VFR
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January 30, 2025, 23:07:00 GMT
permalink Post: 11817743
I can't speak for the USA, but my understanding was always that the flight rules for the CRJ don't change, unless the crew cancel their IFR plan: ie flying a visual approach doesn't change the flight rule status. The crew can still expect IFR separation from other IFR & SVFR flights, & traffic information on conflicting VFR flights.
In the US does an agreement to make a visual approach regardless of airspace classification, cancel IFR separation requirements for the ATCO?
Subjects
ATC
ATCO
CRJ
IFR
Separation (ALL)
VFR
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January 30, 2025, 23:08:00 GMT
permalink Post: 11817745
a good test of that principle is what happens if the crew go around having commenced a visual approach. They are expected to fly the MAP and not go off script.
In Europe, the radar service can be terminated on an instrument approach once descending into uncontrolled airspace. But the a/c is still IFR.
In Europe, the radar service can be terminated on an instrument approach once descending into uncontrolled airspace. But the a/c is still IFR.
Subjects
ATC
IFR
Radar
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January 30, 2025, 23:24:00 GMT
permalink Post: 11817756
OK so what's your interpretation of the rules here then?
The airliner is under IFR rules on its flight plan until it gets changed to a different runway, when it's then VFR.
The chopper is under VFR, stooging along a river at 200 ft and avoiding traffic on approach to Reagan by visual clues alone.
Radar useless as the aircraft are too low.
Airliner TCAS useless as inhibited, even if it can decode the military transponder's data.
Radio situational awareness compromised as chopper on UHF, airliner on VHF. So each aircraft can neither hear the other nor the ATC instructions to that aircraft.
It's difficult to see aircraft at night against a backdrop of a city with thousands of lights. And when you're gonna hit something, as others have said, that light doesn't move relative to you, so you don't notice it - it just blends into the background lights.
It only takes the chopper to misidentify the aircraft it's supposed to go behind and to therefore turn into the path of the airliner it was supposed to avoid - draw the map with the vectors and it all makes sense. These two aircraft ended up in the Potomac, but they could have ended up in much worse places in terms of loss of life on the ground.
Seems to me it's been an accident waiting to happen for some time.
The airliner is under IFR rules on its flight plan until it gets changed to a different runway, when it's then VFR.
The chopper is under VFR, stooging along a river at 200 ft and avoiding traffic on approach to Reagan by visual clues alone.
Radar useless as the aircraft are too low.
Airliner TCAS useless as inhibited, even if it can decode the military transponder's data.
Radio situational awareness compromised as chopper on UHF, airliner on VHF. So each aircraft can neither hear the other nor the ATC instructions to that aircraft.
It's difficult to see aircraft at night against a backdrop of a city with thousands of lights. And when you're gonna hit something, as others have said, that light doesn't move relative to you, so you don't notice it - it just blends into the background lights.
It only takes the chopper to misidentify the aircraft it's supposed to go behind and to therefore turn into the path of the airliner it was supposed to avoid - draw the map with the vectors and it all makes sense. These two aircraft ended up in the Potomac, but they could have ended up in much worse places in terms of loss of life on the ground.
Seems to me it's been an accident waiting to happen for some time.
"Radar useless as the aircraft are too low." - It seems there's valid radar returns from both aircraft. the FAA has a good diagram of the Potomac TRACON radar sites, about 10 different radars, and having visited the TRACON several times, they readily explain there's another nearly facility that is a duplicate of their radar feed, but for national security. I assume there's coverage till the river service for security to prevent someone from sneaking up the river with bad ideas
"Radio situational awareness compromised as chopper on UHF, airliner on VHF. " - I fly in the area and in my experience everyone is on the same VHF, they might be also duped to UHF and can hear everybody on my handheld. You hear AF-1 all the time on freq.
"The chopper is under VFR, stooging along a river at 200 ft and avoiding traffic" - Most of the area NE of the airfield in a prohibited area, and there's a lot of military installations within 5 miles of DC that they are shuttling around, so that path seems perfectly acceptable given the numerous constraints. there's nothing wrong with a helo corridor as long as you stay within it and maintain the prescribed altitude. Also, it's not like KDCA is some secret place, the flight paths are pretty well known if that's where you work. It's popular to sit in parks on both ends and watch the planes, there's literally millions of local people that know exactly the planes are coming and going on both directions. so if you're a helo there, you know where the hot spots are. Likewise, its not just any helo in that area, everyone is vetted, fingerprinted in the inner FRZ.
" on approach to Reagan by visual clues alone" - The UH-60 was not going to DCA, the assumption was it was using the helo route 4 corridor. All the UH-60Ls I've seen have full glass with moving map and I'm assuming a magenta line for the helo corridor.
Fun Fact - Calling it "Reagan" will get you tarred and feathered in the area. Folks refuse to utter the name and for years (decades) the Metro refused to rename the station until legally forced.
Last edited by Senior Pilot; 31st January 2025 at 00:05 . Reason: Prescribed/proscribed
Subjects
ATC
Accident Waiting to Happen
DCA
FAA
Hot Spots
IFR
KDCA
Pass Behind
Pass Behind (All)
Radar
Route 4
Situational Awareness
TCAS (All)
VFR
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January 31, 2025, 00:08:00 GMT
permalink Post: 11817780
AIM 5-4-23
e. A visual approach is not an IAP and therefore has no missed approach segment. If a go around is necessary for any reason, aircraft operating at controlled airports will be issued an appropriate advisory/clearance/instruction by the tower. At uncontrolled airports, aircraft are expected to remain clear of clouds and complete a landing as soon as possible. If a landing cannot be accomplished, the aircraft is expected to remain clear of clouds and contact ATC as soon as possible for further clearance. Separation from other IFR aircraft will be maintained under these circumstances.
Subjects
ATC
IFR
Separation (ALL)
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January 31, 2025, 00:34:00 GMT
permalink Post: 11817798
I am wondering the same thing, in the UK/EU unless the IFR crew specifically cancels their IFR plan with ATC, (it can be done immediately on frequency), IFR separation requirements still apply.
In the US does an agreement to make a visual approach regardless of airspace classification, cancel IFR separation requirements for the ATCO?
In the US does an agreement to make a visual approach regardless of airspace classification, cancel IFR separation requirements for the ATCO?
However, note that the airspace class at major US airports is B (rarely used elsewhere). Cancelling IFR in Class B does not relieve ATC of separation responsibility because VFR flights must still be separated from all other flights ( VFR separation standards here ). Separation responsibility only transfers to a pilot when they accept ' visual separation ' and the controller must continue giving separation instructions until that point. Aircraft can be given 'visual separation' against other aircraft, including IFR aircraft as happened here, without the other aircraft needing to have the traffic in sight. The controller must advise the other aircraft that visual separation is being applied if the flight paths are converging .
None of that is necessarily a problem.
The problem is reliance on visual separation at night. The ease with which the eye is drawn to bright lights (which may not be the lights of interest) and inability to perceive depth and distance from a point source of light (made worse by NVG) make it a high risk activity even between combat aircraft. To permit it to be relied upon for protection of airline traffic is madness.
Last edited by Easy Street; 31st January 2025 at 01:14 .
Subjects
ATC
ATCO
IFR
Night Vision Goggles (NVG)
Separation (ALL)
Traffic in Sight
VFR
Visual Separation
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January 31, 2025, 01:18:00 GMT
permalink Post: 11817827
OK so what's your interpretation of the rules here then?
The airliner is under IFR rules on its flight plan until it gets changed to a different runway, when it's then VFR.
The chopper is under VFR, stooging along a river at 200 ft and avoiding traffic on approach to Reagan by visual clues alone.
Radar useless as the aircraft are too low.
Airliner TCAS useless as inhibited, even if it can decode the military transponder's data.
Radio situational awareness compromised as chopper on UHF, airliner on VHF. So each aircraft can neither hear the other nor the ATC instructions to that aircraft.
It's difficult to see aircraft at night against a backdrop of a city with thousands of lights. And when you're gonna hit something, as others have said, that light doesn't move relative to you, so you don't notice it - it just blends into the background lights.
It only takes the chopper to misidentify the aircraft it's supposed to go behind and to therefore turn into the path of the airliner it was supposed to avoid - draw the map with the vectors and it all makes sense. These two aircraft ended up in the Potomac, but they could have ended up in much worse places in terms of loss of life on the ground.
Seems to me it's been an accident waiting to happen for some time.
The airliner is under IFR rules on its flight plan until it gets changed to a different runway, when it's then VFR.
The chopper is under VFR, stooging along a river at 200 ft and avoiding traffic on approach to Reagan by visual clues alone.
Radar useless as the aircraft are too low.
Airliner TCAS useless as inhibited, even if it can decode the military transponder's data.
Radio situational awareness compromised as chopper on UHF, airliner on VHF. So each aircraft can neither hear the other nor the ATC instructions to that aircraft.
It's difficult to see aircraft at night against a backdrop of a city with thousands of lights. And when you're gonna hit something, as others have said, that light doesn't move relative to you, so you don't notice it - it just blends into the background lights.
It only takes the chopper to misidentify the aircraft it's supposed to go behind and to therefore turn into the path of the airliner it was supposed to avoid - draw the map with the vectors and it all makes sense. These two aircraft ended up in the Potomac, but they could have ended up in much worse places in terms of loss of life on the ground.
Seems to me it's been an accident waiting to happen for some time.
It's eerily similar to the P-63/B-17 midair- a blind collision that was instantly apparent how flawed the basic plan was, even though it had worked before.
Subjects
ATC
Accident Waiting to Happen
IFR
Pass Behind
Pass Behind (All)
Radar
Situational Awareness
TCAS (All)
VFR
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January 31, 2025, 04:03:00 GMT
permalink Post: 11817897
Many years ago, shortly after I got my instrument rating, I flew a friend from St. Paul to St. Louis in a rented C172. Of course I filed IFR, being anxious to get more practice in the system. We were maybe 10-20 miles SW of MSP in level flight when I heard the controller tell a Northwest flight of Cessna traffic somewhere in our direction; there was another Cessna in the area as well. NW called \x93traffic in sight.\x94 Maybe 10 seconds later my passenger pointed very excitedly behind us and to our left. There was a NW 727, maybe 200-300 yards behind us and climbing through our altitude from left to right.
Very
fast.
I\x92ve always wondered if they really saw us or the other Cessna. It was probably the closest I\x92ve ever been to another aircraft not in the pattern. It felt way too close.
\x93See and avoid\x94 is really not the basis for safe separation of traffic in the air. Depending on it at night in airspace as busy as DC is choosing poorly.
TCAS has mostly solved the separation problem for every phase of flight except very close to the airport or on the ground. If the industry is going to short-staff ATC and keep cramming more traffic into the same airspace, the industry needs to develop and equivalent solution for those phases of flight as well.
I\x92ve always wondered if they really saw us or the other Cessna. It was probably the closest I\x92ve ever been to another aircraft not in the pattern. It felt way too close.
\x93See and avoid\x94 is really not the basis for safe separation of traffic in the air. Depending on it at night in airspace as busy as DC is choosing poorly.
TCAS has mostly solved the separation problem for every phase of flight except very close to the airport or on the ground. If the industry is going to short-staff ATC and keep cramming more traffic into the same airspace, the industry needs to develop and equivalent solution for those phases of flight as well.
Subjects
ATC
IFR
Separation (ALL)
TCAS (All)
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January 31, 2025, 04:12:00 GMT
permalink Post: 11817901
SLF here, so please don't shout.
It doesn't seem "fair" for aircraft like the CRJ, that in busy, complex airspace, another aircraft can request and receive VFR, meaning in broad terms, they're outside of ATC's guardrails. CRJ now have an aircraft in the vicinity that isn't being controlled by ATC.
Doesn't seem like a good process to an outsider.
It doesn't seem "fair" for aircraft like the CRJ, that in busy, complex airspace, another aircraft can request and receive VFR, meaning in broad terms, they're outside of ATC's guardrails. CRJ now have an aircraft in the vicinity that isn't being controlled by ATC.
Doesn't seem like a good process to an outsider.
Subjects
ATC
CRJ
DCA
IFR
VFR
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