Posts about: "VFR" [Posts: 141 Page: 6 of 8]¶

Indeed , as reminder this is the official ICAO definition of class B airspace :
My bold. so in essence not by one of the pilots. But this is ICAO, not FAA .

I agree that is a solution, indeed the obvious one from my European point of view. What I was trying and failing to think of was a route design which guaranteed separation without ATC intervention, which is what I thought meleagertoo was asking for.

However, from a US point of view, this is arguably the solution which was in place on the night. It's just that the means of actively keeping the traffic apart, ie visual separation, failed. I am prepared to accept that FAA-style "visual separation" is slightly more robust than "see and avoid" in that it requires ATC to confirm that the pilot has the specific traffic in sight before relaxing separation minima, but the question for the FAA is whether "slightly more robust" is good enough when airliners are involved, particularly at night given the increased potential for misidentification.

I am not sure the subsequent line of discussion over how Class B requires ATC (not pilots) to separate all traffic is a very productive one. Any separation instruction given by ATC relies upon the pilot executing it, for instance by maintaining the cleared altitude. Here, it relied on the pilot not colliding with the specific traffic he had confirmed visual contact with. So far as the FAA is concerned, that's a sufficient degree of control and differs from the "see and avoid" principle applicable to VFR/VFR in Class C, and VFR/Any in Class D. Again, the question is whether that's appropriate.

That last point gives me an opportunity to make an observation I've been pondering for a while. Many European airport control zones are Class D, where on a strict reading of ICAO, VFR traffic is not required to be separated from IFR. But how many of us know a Class D zone where the controller gives traffic information and lets VFR traffic merge with IFR under see and avoid? In practice, European and especially UK ATC exercise a greater degree of control than is strictly required by the ICAO classification. At least in my experience, US airspace is operated closer to ICAO specifications ("visual separation" nothwithstanding).

"Visual separation" is different from "see and avoid" in that the controller must confirm that the pilot has the factor traffic in sight before approving visual separation. The controller is only delegating the "avoid" part of the task, not the "see", which must be confirmed before the separation minima are removed. That, at least in my understanding, is how the FAA argues it to be compliant with Class B requirements. It's obviously vulnerable to misidentification of the factor traffic; don't think I'm defending it!

When genuine "see and avoid" applies (Class C VFR/VFR, Class D VFR/Any) the controller does not need to confirm that VFR pilots have visual contact before allowing separation to reduce, because there *are no* separation minima. At least, not according to ICAO.

As I mentioned earlier, European and especially UK ATC tends to apply more stringent separation than ICAO requires. The 'ATC duty of care' argument in the UK results in its Class D being operated in a similar way to US Class B, in my experience.

This sort of ties in with EasyStreet s comments on UK ATC in Class D ops which I used extensively. The key is being sure you really can see the actual aircraft ATC want you to see. In many cases, it is easy - it was SOPS for my time travelling about with my pax or when enjoying myself doing a bit of private flying. I'd say this happend (commercially) 80% of the time - otherwise I was IFR. The real difference between my experience and what happened here is 2-fold:-

- Traffic density.
- Routing configurations.

In my experience at UK regionals, there is usually just not the taffic density we see here (tho it can be busy at times at certain "rush hours"!) and, also, the ergonomics of the flightpaths were such that you weren't looking back up a busy approach path with many aircraft "in stream" thus making "picking the one" almost impossible. If I had to join a stream I was either changed to IFR for the ILS to "avoid an excessive delay" (which was ATC basically saying to me "we can't do this safely under VFR" which got my vote each time) or, if a smaller stream, I'd be extended downwind by App who effectively then handed Twr a workable solution which App had "engineered". At no time was I given anything more than a simple "pick 1 out of 1"-type or, very rarely, a "1 out of 2" scenario and never where the Twr were "trying to wallpaper a room, tile a bathroom and re-wire the main fuse box" at the same time. In the odd "1 out of 2" situations I was always asked "Do you see the 2 aircraft on Final?" and, unless I saw both, it was "Negative, only 1 in sight!".

The takeaway is that what's "legally allowed" is sometimes "not practically wise" and that seems to have been the undoing here.

I have noticed this and it really hosed me one night. Coming home to KMTN from KVKX (right next to DCA actually) I was VFR in the Class B at 2000 feet. The ceilings were dropping going north, but traffic at KBWI was all going along with calling the field in sight at 2500 feet. BWI wanted me above their landing traffic, so I was told to climb to 2500, which put me in IMC. There was NO WAY anyone was visual at 2500, but they didn't want to deal with a pop-up IFR flight in the middle of a busy push, so I got "You will be in the clear at 2500, everyone is reporting airport in sight". The message was very clear, don't screw the whole thing up! At least they didn't ask me if I could see any specific airplane, I guess they knew what the answer would be.

It may seem that way but not the case. Any of the flight tracker programs show regular helicopter activity inside the Beltway with plenty of medical helo ops plus LEO ops (FFX, PG, DC, MSP, USCG). Even a few news helos. What does seem to have changed is PAT ops inside the Beltway, at least temporarily. Training flights have shifted outside the Beltway to a variety of locations, including Route 9. Two PAT flights today circumnavigated the Beltway.

Not sure what you mean by this comment. CW3 Roth interview explained the training requirement for Route 1/4 ops. Question is whether these training flights can be conducted safely. I think they can as long as ATC doesn\x92t delegate their primary responsibility for Class B separation. It is politically untenable to resume Route 1/4 PAT training flights at present. I suspect 12th AB and DCA ATC are reviewing their previous policy that VFR visual separation is safe along these routes.

Seems like the line you added on the chart is exactly what the Pentagon east/west arr/dep should look like. VFR helo Route 5 ends at Air Force Memorial and then it’s a transition route to Pentagon and Washington Monument. Helo traffic avoiding directly overflying the Pentagon.

One would hope traffic arriving/departing the Pentagon is coordinated tower to tower with DCA if traffic is approaching 15 and departing 33….

But what about the arrowed line of the map to the west of the Pentagon, connecting Route 1 and Route 5? Isn't that the route the helipad, twice as far from the 15 piano keys?

One would definitely hope that traffic is coordinated. From my perspective (17th floor, facing east) the Route 5 traffic is just above the level of the Arlington Ridge treeline as it enters my FOV and is then masked by high-rises as it follows the red line over 395. The terrain and buildings are next to 395 so the 196-foot tower can't see over them. Using GE Pro it looks as if the helos are seconds from the 15 approach before the tower has line of sight to them.

Was the controller really on his own?

The local controller had an Assistant ATC and a Supervisor to coordinate, monitor and regulate the traffic.

Class B airspace "ATC Clearances and Separation. An ATC clearance is required to enter and operate within Class B airspace. VFR pilots are provided sequencing and separation from other aircraft while operating within Class B airspace." source FAA Class B
One way to determine how the application of sequencing and separation to VFR pilots in this airspace was being applied would be to listen to the audio and watch radar replays over the weeks and months prior.

By Airport Operator do you mean the airport itself or the ANSP?

Hiya WR 3-6 , thanks for your reply. A busy day today so I'll give this more time tomorrow if I may! But interesting points again - and I'm a bit clearer too on this "discretionary" aspect - I think!!!!

Hi missy , sorry, what I was trying to say was, and this is from further back in the Thread, it is my understanding that often there is 1 controller handling main arrivals & departures with another controller handling local traffic on the heli routes etc. As is often the case, at quiet times, one position closes and so the 1 controller is now controlling both. That is very common practice both at airports and en-route. The others are, indeed, there in support but things happen (eg the Supervisor is asked a question or gets a phone call - similar with the Assistant.). Not saying that happened here but it illustrates the support aspect of those roles and what can happen.

Now, one could say, "Well, there was a fairly steady flow of (maybe) 10 aircraft landing/taking off. So, 1 extra helicopter is not much more to add in!". True ...... but ...... an example. A mainline train arrives at a major London Station and, at once, all the doors open and several 1000 people all get off together and start heading up the stairs to the ticket barriers. The flow of traffic is heavy but quite ordered as the flow is all in one direction and so, while traffic density up the stairs maybe slows it down a bit, the flow is nicely ordered. Picture now, H 'n' H , being in a rush and so being one of the first off the train arriving at the ticket barrier only to realise - Durrrr - he's left his case back on the train. Being not-too-bright, I decide the quickest way to go back is down the same stairs I came up, and hence back to the train. Of course there's only 1 of me going down and several 1000 coming up. But to an onlooker gazing down, the effect of my single trip back against the several 1000 heading up has had a significant effect. TBH, H 'n' H is causing a fair degree of chaos as he pushes past everyone fighting his way back down the stairs against the flow. A few choice comments are being made by his fellow pax! What we have is a disproportionate effect caused by 1 vs 1000's.

So, while I'm no expert in how the brain works, usually the ATCO is dealing with a steady flow S - N and is sequencing things in their mind to smoothly land and depart traffic, slotting people in and out of the queue to achieve an orderly, safe, flow. All of a sudden, their "mental flow" now has something working in the other direction which all needs a bit more thought to ensure that everything remains safe. OK, 1 helo is not much, but it requires a disproportionate amount of extra "computing" compared to, say, adding another 1 aircraft into the main flow, to ensure safe separation. Was that why the "Own visual separation" offer was taken up? Now, rather than managing the contraflow, the ATCO only has to "monitor" the singleton swimming against the tide - which they were to a degree. Just a thought.

Spot on! I'm not sure how long such tapes are kept? Usually it is a defined period after which the tape is recycled into the "system". Of course, looking further back, and in a perfect world, you could assess ATC SOPs against the buildup in traffic over the years and see how that's affected things over time. Was it the case of "a death by a 1000 cuts" which WR 3-6 cited? Sadly, I suspect we'd need a crystal ball to study that. But retired Controllers could give a fairly good insight.

I mean the Airport Operator running the airfield. So, in the UK, that could be a company who then employ the Twr controllers to run that side just as they employ or contract Baggage Handlers, Cleaners, etc, etc. The UK ANSP (NATS) generally pick up everything above 4000 ft tho the actual hand-offs vary tactically and there can be local variations to suit specific airspace. So, for example, from memory, the Channel Islands work up to a higher level before en-route takes over. Below that, its up to the Airport Operator to staff their operation and make sure it's all safe and sound.

Anyway, better dash as already late........! Before yet more chaos is caused by H 'n' H !!!!!!

I refer to the case of Lufthansa identifying night visual separation as a safety issue and deciding not to allow it, then one of their aircraft having to divert from SFO because of this decision. AA banning DCA 33 might have had the same kind of result.

Anyway, after 72 pages it seems fairly clear that separating IFR from VFR at night by visual means inside the circuit pattern of a major airport is not a great plan. This could happen anywhere in the US and it would be an interesting exercise for the NTSB/FAA to see how many separation losses there were at other airports, as they have the software to do that. It is easy to fixate on this accident and the immediate environment when similar setups exist all over the place. It\x92s not just about helicopters and the military - civil and fixed wing on that kind of clearance could be just as risk-bearing.

I landed many times on 33 in a 727. It was not even considered difficult with a reasonable headwind which is why you would take 33 in the first place. Today with the children of the magenta line flying I suspect it might be considered a bit more challenging even though more modern aircraft with autothrust and excellent mapping it should make it even easier.
There is one point not mentioned in the thread. The two people with probably the best overall situational awareness of what was developing would have been the RJ crew. They received a traffic alert 18 seconds before the collision and the TCAS should have displayed the threat all the way to impact. I never allowed a threat inside a half a mile on a collision course even if they claimed they had me in sight unless I could visually see the threat. I got scolded by tower at DCA for going around once when we could not see VFR traffic tower said had us in sight. I didn\x92t care even though it was daylight. With a threat bearing down on TCAS you need to take action to mitigate the threat. Hoping they really have you in sight is not a good strategy.

(emphasis added)

After waiting a few days to find out whether replies would be posted by other knowledgeable aviators besides Sailvi767, and despite status as just SLF/attorney, I've got to ask: Is it a reasonable inference to draw from the quoted post, especially the part underlined, that the RJ crew perhaps was not completely without responsibility for the collision? I do not lightly (this has been batted about previously) even so much as imply responsibility for accidents on the part of pilots. Yet the quoted post seems to suggest that in this specific instance for the specific reasons stated, the RJ crew might have had a share of the responsibiity.

I admit I had thought of the RJ crew as having been not aware of any information suggesting or indicating immiment danger (despite having written an academic paper about Uberlingen a few years ago). And, the facts which potentially lead to assigning a share of responsibility to the RJ crew also would then change the contours and progression of the litigation, quite dramatically, and not only in terms of impact on familly members. Bringing in the airline as a defendant would direct the complaint drafter's mind to questions of the most effective style, organization and content to make the case for punitive damages. Forum readers following the legal aspects of the accident on the thread may recall that punitive damages are not recoverable in a tort claim brought against the United States Federal Government The airline company or companies here have no such protection.

That\x92s perhaps a VFR response and appropriate here, but you cannot deviate from a clearance on just TA. TCAS training since its adoption has been to not maneuver for a TA, only for an RA.

I never received that training. You can as a pilot use your emergency authority to deviate from any clearance. Responding to a RA is mandatory. Responding to a traffic alert is up to the pilot flying. Yes they don’t want pilots routinely violating clearances for initial Traffic alerts. They want you to respond to the RA if it occurs. Many pilots do take action within their clearance to prevent a TA from becoming a RA. A simple change in rate of decent or climb can often accomplish that. Below 1000 feet knowing that RA’s are inhibited you are saying you would do nothing with a threat displayed on a collision course? What will your thought process be after the collision? Hey, that TCAS was right!
Keep in mind they were on a visual approach and that you can go around from any approach for any situation you deem unsafe. We will agree to disagree that a threat at the same altitude and constant bearing decreasing range displayed on the TCAS inside 3000 feet does not warrant crew action.

"Originally Posted by FullMetalJackass
If I get a traffic alert in my personal aircraft (I don't get RAs, just traffic warnings), I'm taking action to increase the altitude difference between me and the conflicting traffic. ."

Yes, we are trained to use TAs to find traffic, and RAs to avoid, but I think 767 is right about things being different when you know that you wont get an RA.

Pretty clear the Army helicopter was too high, a little off course, and certainly did not have the plane in sight the controller wanted them to have in sight. Controller busy and separation left to helicopter crew.

So may 'what ifs' could change the outcome. A "caution - VFR helicopter traffic below - southbound along river" call out to the CRJ crew by ATC could of made the difference. The helciopter crew staying at or below 200 could of made the difference.

Its amazing that this was considered "the norm" in that area.

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

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

Something smells wrong about some of this.
(I need to see a bit more of the documentation on the difference between the hard altitude (200') that I was under the impression was on that route, as opposed to the "recommended altitude" statement made there...maybe it will make more sense to me then).
As to altimeter errors.
The UH-60L has a radalt.
Are you trying to tell me that the alleged acceptable error for a rad alt is 80'-130'?
I think not.
I doubt that the rules have changed that much since I was last flying a Blackhawk. (yes, it has been a while).
Will do a bit more reading, thanks.

I\x92ve been listening to the NTSB hearings while doing other things last couple of days. All I can say is the FAA testimony is wild .

Normalisation of deviance doesn\x92t even come close.

- Airspace design. The heli route stepping down to 200ft max lead some army pilots to believe it gave clearance from DCA traffic. Spoiler. It did not.
- Controller workload \x93Just make it work\x94 was a common attitude at DCA
- FAA not actively tracking TCAS RA \x93incidents\x94 as it could skew data.. maybe it was correctly applied visual separation etc. Need to look at the background etc. Yeah. But it generated an RA 🤬
- FAA refusing requests for traffic \x93hot spots\x94 on low level VFR charts as \x93hot spots\x94 are on ground charts only.
- PAT25 wanted visual separation from the CRJ. ATC was required to inform the CRJ crew another aircraft was applying visual separation to them. They didn\x92t.

Honestly from a European perspective. It\x92s quite bone chilling.

I feel this was a systemic failure. Airspace design and Risk Normalisation.

And my heartfelt condolences for the pilots, of both aircraft, and everyone else involved including the ATCOs. Not that there weren\x92t issues\x85 but in the Swiss cheese model, the FAA bought the cheese, drilled holes in it, and invited everyone to take a look inside.

Slightly surprised by some NTSB comments as well\x85 they were presented that the heli was straight ahead on the CRJ TCAS simulation presentation. But in actual fact the CRJ was circling in a left turn for runway 33. It was stable at 500ft but in a left turn to line up with the runway\x85 wings level at 300ft. It was challenged by the airline/ALPA but I would hope the NTSB would have picked up on that.

Low point of the whole hearing was Jennifer Homendy halting proceedings and moving witnesses to different seats, as one of the FAA managers elbowed a colleague while she was giving testimony - at which point she went quiet. Infernce being she was being reminded to stop talking.