Page Links: First Previous 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 Next Last Index Page
| mechpowi
February 04, 2025, 14:51:00 GMT permalink Post: 11821483 |
Sorry, that's nonsense (fixed wing military NVG experience here). It is true to say that NVG can be raised and lowered as required to alternate between aided and unaided search, but it does not mean that lookout is unaffected. Whenever the NVG are lowered, there are two large objects almost completely obscuring unaided vision and drawing focus to the eyepiece displays. Deliberate, conscious action is required to move the head to expand the aided search area beyond the static field of view. It is exceptionally easy to be deceived by lack of depth perception in NVG, and resolving differences between the aided and unaided pictures consumes mental capacity during the transition between modes. A NVG-only or mixed mode search would most certainly have reduced the helo crew's unaided search time, and therefore their probability of picking up the CRJ in peripheral vision to their left.
Among the many risky things I used to do as a military pilot, including diving towards the ground at 45 degrees in pitch darkness and pulling out on a range cue to miss the ground by 500 feet, one thing which always made the chain of command particularly nervous was closed pattern work on NVG. At home base, only experienced pilots were allowed to wear NVG in the pattern with another aircraft, and even then only one other: their similarly experienced formation wingman. And that was at a remote airfield with only a few military lives at stake and a tower controller monitoring both aircraft like a hawk. In Afghanistan, it was a toss-up whether the most dangerous place to fly fixed wing was over the Taliban or in the closed pattern at Kandahar, with helicopters darting around wearing covert lighting (they of course had an understandably different view of the risks). The idea of flying through the traffic pattern at a busy civilian airport using NVG to avoid airliners simply appals me. Subjects
ATC
CRJ
Night Vision Goggles (NVG)
Reply to this quoting this original post. You need to be logged in. Not available on closed threads. |
| BrogulT
February 04, 2025, 21:02:00 GMT permalink Post: 11821702 |
Yes, it\x92s a moot point. I suspect the low altitude on the heli routes are to allow them passage when the main runway 01/19 is in use, rather than to provide any vertical separation if there\x92s an aircraft using 33. The helicopter chart has holding points along it that probably should have been used.
Subjects
ATC
PAT25
Separation (ALL)
Vertical Separation
Visual Separation
Reply to this quoting this original post. You need to be logged in. Not available on closed threads. |
| BrogulT
February 04, 2025, 22:34:00 GMT permalink Post: 11821762 |
"5342, helo traffic on your right 1/4 mile at 300 feet, has you in sight". The CRJ FO might just have taken a closer look out the side window with that. Or, like you, they might have opted to go around. Subjects
ATC
CRJ
DCA
IFR
Separation (ALL)
TCAS (All)
Traffic in Sight
Visual Separation
Reply to this quoting this original post. You need to be logged in. Not available on closed threads. |
| procede
February 05, 2025, 09:41:00 GMT permalink Post: 11822038 |
Additionally, any helicopters flying in such congested airspace should have a display showing other traffic so they know where to look outside. Subjects
ATC
IFR
Separation (ALL)
VFR
Visual Separation
Reply to this quoting this original post. You need to be logged in. Not available on closed threads. |
| RetiredF4
February 05, 2025, 10:12:00 GMT permalink Post: 11822066 |
Imho the altitude sectored restrictions were never suitable and safe to deconflict helicopter traffic from traffic to finals 01 and 33, but were meant to deconflict takeoffs from 15 and 19. Could it be that someday some clever soul thought to solve increasing traffic demands by using 33 and 01 for landing despite traffic in the helicopter routes under visual separation rules, ignoring thereby that now all layers of safety had been removed bare the eyes of an helicopter crew? Subjects
ATC
IFR
Separation (ALL)
VFR
Visual Separation
Reply to this quoting this original post. You need to be logged in. Not available on closed threads. |
| meleagertoo
February 05, 2025, 10:32:00 GMT permalink Post: 11822080 |
Proper aviation safety is based on having multiple layers, in this case it was reduced to one (the helicopter pilot maintaining visual separation), which clearly failed. At least there should be active vectoring by ATC AND (visual acknowledgment of BOTH cockpits OR at least 500 ft vertical OR 1.5nm of horizontal separation). And even this is pushing it.
Additionally, any helicopters flying in such congested airspace should have a display showing other traffic so they know where to look outside. You cannot actively vector a helo at 200ft over the black hole of a river in the middle of an urban environment or anywhere else. You'd kill helos every month doing that. If the helo were at 100ft or so there would be no need for vectors (you never get them in London, just holding, ie orbits if necessary). Visual acknowlewgement from the aeroplane is totally unnecessary as he is on finals to land which give total priority over all other traffic. It is up to the give-way traffic to identify and acknowlege. 500ft vertical I agree with, in which case 1,5 miles is totally unnecessary and ridiculously excessive. This discussion is being considerably bogged down by a really surprising (to me) absence of understanding of helos and helo ops by people who clearly only fly f/w IFR and seem to have no concept of how the rest of the aviation world works. Strangely, there are other ways of aviating safely without staring exclusively at an instrument panel, following a magenta line and doing only what someone miles away in an office tells you. You simply cannot try to apply IFR airline type procedures and mindset to low level VFR traffic. It's like a train driver trying to dictate railway rules to a motorcyclist and being unaware that motorcycles just don't operate like trains... imaginingthat helos can or would come to a free air hover for separation is another example of unrealistic imagnation over reality. Please, if you don't know anything about helicopter ops, please don't try to apply procedural IFR or Hollywood mindsets/misapprehensions to them as if there is no other waay of flying. Last edited by meleagertoo; 5th February 2025 at 10:54 . Subjects
ATC
CRJ
Hover
IFR
Separation (ALL)
VFR
Visual Separation
Reply to this quoting this original post. You need to be logged in. Not available on closed threads. |
| meleagertoo
February 05, 2025, 11:21:00 GMT permalink Post: 11822123 |
Just for illustration, this is how it's done in London (or was some time ago last time I did this sort of work). Accurate compliance with routes is strictly enforced and clearances are SVFR day and night unless this has changed. Almost invariably clearance to enter would state the route/s ie 'H4 H3 Bagshot Mast' (straight through) and no other instruction required - that takes you E -W right through the centre of London and out to the W passing 5 miles S of Heathrow. Right hand rule applies and opposing traffic on the route is always advised.
Usually, only if crossing LHR you'd be cleared to enter via requested route with limit Bedfont/Sipson, sometimes Airport Spur to hold (orbit) and change from Heathrow Special to Tower for the crossing itself. There's a further hold at Twin Taxiways between the runways. Altitudes are shown. Note there is usually unrestricted passage on routes H3 and H10 along the river directly under the approach. This system works seamlessly and with - to date - total safety. Accepted the aairport we are discussing has more varied runway directions than Heathrow so the situation would be a bit more complex but I can't see why a similar system couldn't be devised - with defined clearance limits, sensible vertical separation and, critically, coherent and specific controller voice procedure. There's no reason not to make landing traffic aware of helos holding close in if appropriate and indeed that happens, but no way is their visual contact required. The entire system operates on visual 'separation'. Helos cross visually behind traffic as cleared, but with vertical separation. It's as safe as the system can be made. How else could it work? It requires no controller vectoring and the time and space margins that would be required if radar separation was used would render the slick, efficient visual system cumbrous, unacceptably high end unnecessary workload and probably unworkable. Please, once again let's stop applying this insular f/w procedural IFR mindset to VFR helo traffic. There seems to be a procedural IFR mental blockage that can't see that 'visual separation' occurs in three dimensions, not just two. Helos are perfectly capable of ensuring visual separation as long as the traffic has been correctly identified and with vertical separation as here even if a mistake is made there is 800ft clear vertically. Also, VFR does NOT mean, as many seem to imagine, blundering about randomly at will, it is often every bit as disciplined and controlled as IFR as Shackman reiterates below, these routes are rigidly enforced to within a hundred metres or so and woe betide the transgressor. The elephant in the room here is a combintion of a ridiculously hazardous two-dimensional crossing procedure combined with culpably sloppy & imprecise r/t which offers no second slice of cheese, not matters of visual separation. I'm well aware that our transatlantic cousins are sensitive to criticism of their relaxed, easygoing and informal ways in the air but in this case they self-evidently were the direct cause of 70 odd deaths. While they may regard European style as excessively pedantic there's no doubt whatsoever that had European standards applied here this event would have resulted in nothing more serious than a MOR and an Airmiss report. For those unfamiliar the light grid squares are 1Km so the Sipson and Bedfont reporting/holding points is ony about 500m from the runways.
Last edited by meleagertoo; 5th February 2025 at 12:23 . Subjects
ATC
IFR
Radar
Separation (ALL)
VFR
Vertical Separation
Visual Separation
Reply to this quoting this original post. You need to be logged in. Not available on closed threads. |
| Easy Street
February 05, 2025, 12:57:00 GMT permalink Post: 11822202 |
Accurate compliance with routes is strictly enforced...
...change from Heathrow Special to Tower for the crossing itself. There's a further hold at Twin Taxiways between the runways. Altitudes are shown. Note there is usually unrestricted passage on routes H3 and H10 along the river directly under the approach... ...defined clearance limits, sensible vertical separation and, critically, coherent and specific controller voice procedure.
The entire system operates on visual 'separation'. Helos cross visually behind traffic as cleared, but with vertical separation.
It requires no controller vectoring and the time and space margins that would be required if radar separation was used would render the slick, efficient visual system cumbrous, unacceptably high end unnecessary workload and probably unworkable.
Helos are perfectly capable of ensuring visual separation as long as the traffic has been correctly identified
and with vertical separation as here even if a mistake is made there is 800ft clear vertically. Also, VFR does NOT mean, as many seem to imagine, blundering about randomly at will, it is often every bit as disciplined and controlled as IFR as Shackman reiterates below, these routes are rigidly enforced to within a hundred metres or so and woe betide the transgressor.
meleagertoo forgot to add - and RIGIDLY radar monitored and enforced. Get one bit wrong and you are given immediate radar controlled turn to the nearest 'edge' of the TCA and invited to telephone LHR on landing. I was a pax with our CO flying when he went about 300ft past Kew Bridge on H10 - he wasn't very happy, and to compound his error had an airmiss filed against him by an aircraft on approach to 27R.
I agree with your underlying point that blanket application of IFR separation criteria would be inappropriate. But there are modes of separation besides the false binary of 'visual' and 'IFR' which can be applied to VFR traffic. Last edited by Easy Street; 5th February 2025 at 14:01 . Subjects
ATC
IFR
Radar
Separation (ALL)
VFR
Vertical Separation
Visual Separation
Reply to this quoting this original post. You need to be logged in. Not available on closed threads. |
| NIBEX2A
February 05, 2025, 13:39:00 GMT permalink Post: 11822224 |
Yes, it\x92s a moot point. I suspect the low altitude on the heli routes are to allow them passage when the main runway 01/19 is in use, rather than to provide any vertical separation if there\x92s an aircraft using 33. The helicopter chart has holding points along it that probably should have been used.
I can imagine a scenario where a helicopter crew, who are regular on this route, report the airliner in sight on first call, knowing that by doing so, they avoid an orbit and subsequent delay. With regard to other posts asking why the tower controller didn\x92t pass traffic information to the CRJ crew. Bear in mind that this guy was working flat out, working two positions with pretty constant RT. There may well have been additional tasks such as phone coordination going on in the background which we are not aware of. Again I see a scenario of tower using the absolute minimum RT in an attempt to keep on top of the workload. In his mind, the helicopter has reported the inbound in sight and has stated responsibility to pass behind\x85\x85.job done, onto the next task. I\x92m sure that the investigation will be focusing on why the sectors were combined under these traffic conditions. In my 30+ years of ATC, I have investigated numerous incidents where a significant factor was an overworked controller working combined positions. This can be caused by staff shortages, late reactions to rapidly changing traffic conditions, unit culture or simply a \x93macho\x94 controller who thinks that they can handle everything\x85.until subsequently they find that they cannot! Subjects
ATC
CRJ
DCA
Separation (ALL)
Vertical Separation
Reply to this quoting this original post. You need to be logged in. Not available on closed threads. |
| averow
February 05, 2025, 14:07:00 GMT permalink Post: 11822238 |
Perhaps the helo pilots in the accident were in a very task saturated section of the flight, and on a check ride . The authority gradient would certainly be an unusual one especially if they were wearing NVG's. It's gotta be distracting to be put into such a kludge of an air route that is poorly designed, at night, and having an overworked, understaffed ATC at the same time.
Subjects
ATC
Night Vision Goggles (NVG)
Reply to this quoting this original post. You need to be logged in. Not available on closed threads. |
| BrogulT
February 05, 2025, 20:06:00 GMT permalink Post: 11822511 |
Since they were flying at roughly 100kts (based on the evidence so far presented) a smooth slowdown to 60 knots works, you aren't doing a quick stop, and the plane handles easily.
2. I was sharing (IME means In My Experience) my experience with flying that family of helicopters. Subjects
ATC
PAT25
Reply to this quoting this original post. You need to be logged in. Not available on closed threads. |
| Commando Cody
February 05, 2025, 20:20:00 GMT permalink Post: 11822517 |
Pat I was referring to the ground track change. At their altitude, it wasn\x92t something that would be unnoticed.
Just thinking: they are coming up on the extended centerline of 33, and keep going? Were there any tower or CRJ transmits that indicated the CRJ was on short final? Subjects
ATC
CRJ
PAT25
Separation (ALL)
Traffic in Sight
Visual Separation
Reply to this quoting this original post. You need to be logged in. Not available on closed threads. |
| Commando Cody
February 05, 2025, 20:24:00 GMT permalink Post: 11822518 |
And thank you for sharing your experience. I asked this earlier but haven't gotten a direct reply: If you know, what would have happened if the controller had asked PAT25 to "hold" at the holding point near Hains Point? Is that the function of those holding points and is there some set procedure or pattern?
Subjects
ATC
DCA
PAT25
Pass Behind
Pass Behind (All)
Reply to this quoting this original post. You need to be logged in. Not available on closed threads. |
| dbcooper8
February 05, 2025, 23:51:00 GMT permalink Post: 11822641 |
Questions
Condolences to all impacted.
Questions: Why was PAT 25 search light in the stowed position and not motored to a more forward position? Why are PAT helicopters not M models with FD's so PAT 25 could have been coupled on route 4 while at 200' giving the PF more time to look for traffic? Was there pressure to use NVG along route 4 to meet the hourly requirements for currency? Why did PAT 25 not slow down or hold at Hains in order to pass behind the CRJ as per their clearance? Why was it ops normal after a near miss the previous day and then only one crew chief instead of two for PAT 25? Why was the controller task saturated? Why over the years, as the airport got busier, someone didn't suggest, for night operations, only one aircraft on route 4 or only one aircraft on the approach to 33 at a time and prohibit simultaneous operations? IMO while the CRJ was turning final to rwy 33 PAT 25 may have experienced the CRJ landing lights in the cockpit and may have chosen up and right rather than left and down. Note worthy, PAT 25 RAD ALT gauge scale changes dramatically at 200'. Maybe an upgrade to Dulles with a high speed train connection... Subjects
ATC
CRJ
Close Calls
Night Vision Goggles (NVG)
Pass Behind
Pass Behind (All)
Route 4
Reply to this quoting this original post. You need to be logged in. Not available on closed threads. |
| MarkD
February 06, 2025, 01:07:00 GMT permalink Post: 11822673 |
One thing I\x92ve been wondering about is the PAT mission parameters.
This was a check ride wearing NVGs while runway 33 was open. Do PAT night flights with passengers operate with NVGs all the time, or was this an attempt to check multiple boxes (e.g. NVG currency, route currency, night flight currency) in a single flight? if the answer to the question above is \x93NVGs are generally worn if the Washington area is under some sort of security situation which reduces lit points of reference, but not otherwise\x94 would DCA civil flight ops be continuing in such conditions? What I\x92m driving at is - wouldn\x92t it have been a good idea to reduce the degree of difficulty by squaring in advance with DCA ATC a pause of 33 ops when PAT25 came by, even if an aircraft or two had to hold/delay departure? Subjects
ATC
DCA
Night Vision Goggles (NVG)
PAT25
Reply to this quoting this original post. You need to be logged in. Not available on closed threads. |
| galaxy flyer
February 06, 2025, 01:54:00 GMT permalink Post: 11822687 |
Condolences to all impacted.
Questions: Why was PAT 25 search light in the stowed position and not motored to a more forward position? Why are PAT helicopters not M models with FD's so PAT 25 could have been coupled on route 4 while at 200' giving the PF more time to look for traffic? Was there pressure to use NVG along route 4 to meet the hourly requirements for currency? Why did PAT 25 not slow down or hold at Hains in order to pass behind the CRJ as per their clearance? Why was it ops normal after a near miss the previous day and then only one crew chief instead of two for PAT 25? Why was the controller task saturated? Why over the years, as the airport got busier, someone didn't suggest, for night operations, only one aircraft on route 4 or only one aircraft on the approach to 33 at a time and prohibit simultaneous operations? IMO while the CRJ was turning final to rwy 33 PAT 25 may have experienced the CRJ landing lights in the cockpit and may have chosen up and right rather than left and down. Note worthy, PAT 25 RAD ALT gauge scale changes dramatically at 200'. Maybe an upgrade to Dulles with a high speed train connection... Not the latest model? Guess what, combat units get the latest models. These missions are transport, not combat roles. Budgets and priorities rule. There are VH-60s in the battalion, they\x92re probably not scheduled for check rides or training flights. One RA does not rewrite the schedule, likely not even unusual in DCA. The previous crew may not have passed the event on. I\x92ve had numerous RAs, never a report. The NTSB has stopped asking for reports for events involving VFR traffic. While nice to have, there\x92s no place for a second crew chief to have a forward view. And the CC may or may not be \x93in the loop\x94. They\x92re crew chiefs, not pilots. We had them on C-5 and they mostly slept in flight as they too much to do on the ground. Subjects
ATC
CRJ
Close Calls
DCA
NTSB
Night Vision Goggles (NVG)
Pass Behind
Pass Behind (All)
Route 4
TCAS RA
VFR
Reply to this quoting this original post. You need to be logged in. Not available on closed threads. |
| 51bravo
February 06, 2025, 10:57:00 GMT permalink Post: 11822897 |
Controller instructed very firmly: "PAT25, pass behind the CRJ" There was no such readback, instead: PAT25: "PAT25 has CRJ in sight, request visual separation" Controller: "vis sep approved" Does the "request visual separation" undo the "pass behind"? (just trying to refresh my phraseology understanding, its long time passed, my PPL is not current a long time since) Subjects
ATC
CRJ
PAT25
Pass Behind
Pass Behind (All)
Pass Behind (PAT25)
Phraseology (ATC)
Separation (ALL)
Traffic in Sight
Visual Separation
Reply to this quoting this original post. You need to be logged in. Not available on closed threads. |
| ehwatezedoing
February 06, 2025, 11:28:00 GMT permalink Post: 11822911 |
Subjects
ATC
CRJ
PAT25
Separation (ALL)
Traffic in Sight
Visual Separation
Reply to this quoting this original post. You need to be logged in. Not available on closed threads. |
| missy
February 06, 2025, 11:55:00 GMT permalink Post: 11822926 |
Tower: "PAT25, traffic just south of the Woodrow Bridge, a CRJ, it's 1200 feet setting up for runway 33"
PAT25: "PAT25 has the traffic in sight, request visual separation" Tower: "Visual separation approved" 0:26 here: https://youtu.be/r90Xw3tQC0I?feature=shared Perhaps, and this is big perhaps, it's a pavlovian response to whenever PAT is advised of other traffic. I listened to the TCAS RA missed approach from the previous day, and once again the response from PAT is "request visual separation". It's highly likely that the pilot requests for visual separation is the only way that this Class B airspace can operate with the mix of IFR vs VFR, and aerodrome traffic vs transits. I fail to understand why PAT is using UHF, surely this is another slice of cheese. The use of RWY 33 for arrival makes it easier for the ATC and the aircrew with one less runway crossing after they have landed. To emphasis the point, the following PSA actually requests RWY 33. Subjects
ATC
CRJ
IFR
PAT25
Separation (ALL)
TCAS (All)
TCAS RA
Traffic in Sight
VFR
Visual Separation
Reply to this quoting this original post. You need to be logged in. Not available on closed threads. |
| SASless
February 06, 2025, 12:34:00 GMT permalink Post: 11822952 |
The following article may not have a direct connection to the Collision being discussed but it certainly does mention issues that bear on the general environment under which the aircraft were operating and on how ATC capability might not have had assets that would have assisted in enhancing safety. It does mention DEI, the efforts to privatize the ATC function in the United States to a system similar to those in the UK and Europe and provides some background to why that has not happened. What it does point to is the question of if the US ATC system is adequate to today's needs of the Aviation Industry within the United States.
https://www.city-journal.org/article...control?skip=1 Subjects
ATC
DEI
Reply to this quoting this original post. You need to be logged in. Not available on closed threads. |
Page Links: First Previous 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 Next Last Index Page