Posts by user "missy" [Posts: 11 Total up-votes: 9 Page: 1 of 1]¶

I have struggled to understand why PAT requested visual separation the 2nd time given that it had been approved in the first instance.

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.

Interesting theory. As we all know AA5342 was switched from RWY 01 to a visual approach to RWY 33. Is it just me but I fail to see how a 4\xb0 slope would be achieved on a visual approach.

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?

ATCDumbo
I'm all ears, excellent point. This focus on ADSB-OUT, and ADSB-IN is really a furphy in terms of this investigation to determine the facts, the whole facts and nothing but the facts.

If 5342 had ADSB-IN then PAT25 not having or not displaying ADSB-OUT could be relevant depending on 5342's cockpit display, the training of the pilots and their scanning.
5342 didn't have ADSB-IN so move along, move along, nothing to see, these aren't the droids you're looking for.

**Caveat. If the TWR display were using ADS-B for their updates and to generate Collision Alerts then the absence of PAT25 ADSB-OUT could be relevant.
But would the TWR ATC even know (or care) whether PAT-25 was ADSB-OUT capable. TWR ATC involves looking out the windows and judging the relative positions of aircraft.

Note: ATC display systems are not referenced in the NTSB Aviation Investigation Preliminary Report. This seems to be a glaring omission. So perhaps the NTSB are either very dumb or deceitful or both.

To further illustrate the focus on ADSB. Figure 1 Google Earth image with preliminary ADS-B data for flight 5342 and radar data for PAT25.
The ADS-B plots are 1 seconds intervals, the radar data are 4 second interval (as stated during US Congress Q&A).
So the focus is on the whizz bang ADS-B kit rather than what the ATC saw on their display.

There is reference to ATC radios, and 5342 was on frequency 119.1 MHZ and PAT25 was on frequency 134.35 MHZ. The ATC could've had them on the same frequency (changed PAT25 to 119.1 MHZ) but this would be abnormal. ATC Voice Switch systems like Frequentis, SITTI and Rohde & Schwarz typically have a frequency coupling, whereby controller broadcasts on multiple frequencies (2 or more) and voice communications on one frequency are heard on the other. In this case, ATC would broadcast on 119.1 MHZ and 134.55 MHZ and 5342 would hear instructions for aircraft on 134.55 MHZ, and PAT25 would hear instructions for aircraft on 119.1 MHZ.

Yes, visual separation is typically used close to an aerodrome where the ATC is applying visual separation to reduce the standard from 3NM to something less, 2NM, 1NM, or even less, depending on the circumstance which includes weather (included visibility), day / night, workload to monitor the separation, plus other considerations such as equipment.

I just wonder how many of the January Route 4 Helicopter plots crossing RWY 33 Approach (post 1346) were the result of ATC issuing a control instruction to change the track to closer to the shoreline or further over water.

Use of Route 4 during RWY 33 Approaches or RWY 15 Departures is possible providing a clearance limit is imposed prior to assigning relevant traffic, positive control instruction(s) and in the case of 5342, advising them of the relative position of PAT25 and that PAT25 would be maintaining separation from them.

Example for Route 4 southbound would be a clearance limit of Hains Point. Helicopter would be released past this point when there is no conflict (nil traffic) or assigned separation to avoid (pass behind). If there is a in-line stream of arriving traffic then Route 4 may not be available.

Sydney KSA has something similar for one of their helicopter routes - BONDI 5 (yep, named after the beach), delays may occur when RWY 07 is in use for DEP, or RWY 25 is in use for ARR. Further, the route is not available when RWY 16 PRM approaches are being conducted. Sydney KSA helicopter routes are in text form - TRACK TO..., TRACK VIA..., EAST OF..., and the INBOUND routes to Sydney KSA have a clearance limit in the clearance. A map display is very useful however it should be based on route descriptions. Perhaps the committee of 17 knows the history of the helicopter routes in and around DCA.

Yeah, more than 3000 comments on the UK Daily Mail article in less than 12 hours, plenty of readers prepared to pile on, and quickly.

I really struggle to comprehend why the helicopter not transmitting ADS-B Out is relevant to the accident. What benefit would the other two parties - the CRJ and the TWR Controller gained?
The CRJ didn't have ADS-B IN, and the ATC Surveillance system (radar) doesn't process the data.

DM as required to convince me otherwise.

The transcript of NTSB interview with the local controller is available as one of the articles. Part way through it but was it most obvious, perhaps with the benefit of hindsight, is how poorly constructed some of the questions are - ambiguous and at times, leading.

Actually the original was posted in The New York Times - Karoun Demirjian, Aug. 4, 2025.

Tensions Flare Between Two Federal Agencies Charged With Aviation Safety - The New York Times

Is it MIT-LL TCAS-ACAS SIMULATION STUDY in this list?
#17

Actually, it's not the exact same scenario.

In the case you quote, Tower reported the traffic had you in sight. In the case in question, AA5342 was not provided traffic by the DCA LC.
In the case you quote, did Tower say that the traffic was going to maintain own separation? Did Tower provide a bearing/direction and distance to this traffic? Did Tower provide the height of the traffic?

Your insights are invaluable, as a former air traffic controller I do hope that you continue to post.