AA5342 Down DCA

[PuraVidaTransport]

Watching the wrong aircraft??

If the Army pilots mistook another aircraft for the CRJ they were warned of at least three times, can someone look at the radar and explain which aircraft they thought was the CRJ? I see none they could have possible been watching instead. Considering the distance from one warning to the next and the Army pilot's assurance of seeing the CRJ both times, I don't see how any light on the ground could have been their focus either.

[Lake1952]

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?

[Denflnt]

Originally Posted by artee

My understanding is that the helo crew requested VFR, which ATC accepted. So essentially the helo crew requested the onus. Whether ATC should have accepted is a valid question, but it seems to have been commonplace. Normalisation of deviance?

The helo was always always flying VFR. ATC's job was protecting the CRJ.

[Easy Street]

Originally Posted by PuraVidaTransport

If the Army pilots mistook another aircraft for the CRJ they were warned of at least three times, can someone look at the radar and explain which aircraft they thought was the CRJ? I see none they could have possible been watching instead. Considering the distance from one warning to the next and the Army pilot's assurance of seeing the CRJ both times, I don't see how any light on the ground could have been their focus either.

AAL3130 on final to runway 1. The diagram at my #432 shows how there was only 12 degrees difference in bearing between it and the CRJ. Someone else did a reconstruction showing that the differences in height and range made the elevation angles similar too. It's very difficult to judge distance at night (and impossible on NVGs). And unlike the CRJ, the AAL was pointing directly towards the helo so its landing lights would have looked brighter.

I suspect the helicopter's gradual turn to the right was a result of the pilots fixating on AAL3130 and instinctively flying to pass just behind it, without realising how far away it was.

Edit: this is the reconstruction which shows the similarity in elevation. Captain Steve and Juan Browne have put forward the same theory on their channels but without quite the same compelling graphics.

You Tube

[gretzky99]

Originally Posted by dr dre

There does seem to be a bit of a “we do things differently over here because we’re (quote/unquote) better pilots” attitude. Maybe this will be a wake up call, but given the reluctance to change culture I doubt it.

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 worst of all, everyone involved, from pilots to ATC, think they're the worlds best for making it "work".

[Denflnt]

Originally Posted by PuraVidaTransport

If the Army pilots mistook another aircraft for the CRJ they were warned of at least three times, can someone look at the radar and explain which aircraft they thought was the CRJ? I see none they could have possible been watching instead. Considering the distance from one warning to the next and the Army pilot's assurance of seeing the CRJ both times, I don't see how any light on the ground could have been their focus either.

OK, let's go down that route, as dumb as it is. How many times was the CRJ warned of traffic? I don't recall hearing them being alerted at all, though on short final, low and configured for landing there wasn't much they could do at that point. It is ATC's job to ensure separation for controlled aircraft. If ATC relied solely on the helo to keep from hitting the CRJ, that is a big effing problem.

[galaxy flyer]

Originally Posted by Denflnt

The helo was always always flying VFR. ATC's job was protecting the CRJ.

In Class B, all aircraft are separated, it might visual, it ATC is required to provide separation, IFR or VFR traffic. This standard goes back to the original TCA in 1972.

[gretzky99]

Originally Posted by Denflnt

If ATC relied solely on the helo to keep from hitting the CRJ, that is a big effing problem.

As soon as the helo reported the traffic in sight, that's exactly what happened, and it's exactly how the system is designed.

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.

[galaxy flyer]

Originally Posted by gretzky99

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".

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.

[fdr]

Originally Posted by Lake1952

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?

FAA Order JO 7110.65AA - Air Traffic Control

7.9.4 SEPARATION
a. Standard IFR services to IFR aircraft.
b. VFR aircraft must be separated from VFR/IFR aircraft/ helicopter/rotorcraft that weigh more than 19,000 pounds and turbojets by no less than:
1. 1 ½ miles separation, or
2. 500 feet vertical separation, or
3. Visual separation, as specified in paragraph 7-2-1, Visual Separation, paragraph 7-4-2, Vectors for Visual Approach, and paragraph 7-6-7, Sequencing.

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.

[Lead Balloon]

Originally Posted by photonclock

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?

ATC didn't "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.

[aox]

Originally Posted by dr dre

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’t 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 “we do things differently over here because we’re (quote/unquote) better pilots” attitude. Maybe this will be a wake up call, but given the reluctance to change culture I doubt it.

Spotting the blinky stuff ahead is one thing, especially all going in the same direction on approach

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


​​​​​​

[island_airphoto]

Originally Posted by galaxy flyer

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.

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.

[JRBarrett]

Originally Posted by Lead Balloon

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.

The maximum allowable altimeter error between sea level and 1000 feet is +/- 20 feet, and even a simple stand-alone barometric altimeter has to be able to meet that requirement. The RVSM-certified Air Data Computers on something like a CRJ are typically much more precise than that - more like +/- 5 feet at almost all altitudes. I would assume the air data system on a Blackhawk would be equally precise at low levels.

[Toruk Macto]

The aviation system is past max captivity , many of the operating staff are at %110 on a good day , the rules are being pushed to breaking point . If you grew up in this system it feels normal but if you’re a visitor it’s confronting but hey it’s your system . To “ fix “ it a little will cost a lot of money , more people and time . To fix it a lot would shave points of your GDP , slow the economy and inconvenience many including the rich and powerful .

[galaxy flyer]

Originally Posted by island_airphoto

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.

Well, they got an earful of noise the other night, didn’t they? Maybe, the politicians that cry for ever more service at DCA AND robust “continuity of govt” programs (utter tosh IMO), need to tell the constituents and residents that the noise is necessary. But, that’d take courage.

[Lead Balloon]

Originally Posted by JRBarrett

The maximum allowable altimeter error between sea level and 1000 feet is +/- 20 feet, and even a simple stand-alone barometric altimeter has to be able to meet that requirement. The RVSM-certified Air Data Computers on something like a CRJ are typically much more precise than that - more like +/- 5 feet at almost all altitudes. I would assume the air data system on a Blackhawk would be equally precise at low levels.

Thanks JRB. Regulatory reference? I'm not saying you're wrong. But I can't find anything other than the 75'. (The acceptable 'split' between 2 on board altimeters is a different tolerance, I believe.)

[JRBarrett]

Originally Posted by Lead Balloon

Thanks JRB. Regulatory reference? I'm not saying you're wrong. But I can't find anything other than the 75'. (The acceptable 'split' between 2 on board altimeters is a different tolerance, I believe.)

Appendix ‘E’ of FAR 43, which contains the minimum standards that all altimeters must meet. It includes a table of allowable error at altitudes between sea level and 50,000 feet. Most air data computers on jet aircraft are far more precise than the minimum standards in FAR 43. RVSM certified altimetry systems must meet additional accuracy requirements set forth in Appendix ‘G’ of FAR 91 - but that only applies at altitudes between FL290 and FL410.

The Blackhawk air data system would not be RVSM certified as it could not fly high enough to need it, but the CRJ definitely would be. The CRJ has independent dual digital air data computers, and I assume the Blackhawk does as well.

The “75 foot” requirement does not come from a specific FAR, but from the Airman’s Information Manual (AIM), which states that if the current barometric pressure is set on the ground, that the altimeter should read within 75 feet of the known field elevation at the aircraft’s location or the “altimeter accuracy should be suspect”.

In the US, the altimeters of all civil aircraft that fly under IFR must be tested for required accuracy every 24 months. I assume military aircraft have to meet the same requirement.

FAR 43 Appendix ‘E’ is the basic standard for accuracy, but in the case of something like the CRJ, the AMM (Aircraft Maintenance Manual) Chapter 34 will have additional tests to perform which have much more stringent accuracy requirements set forth than FAR 43.

[kap'n krunch]

Runways 15/33 and 04/22 have been closed until 2/9/25 according to the KDCA NOTAM.

[photonclock]

Originally Posted by Lead Balloon

ATC didn't "allow it".
The procedures allowed the controller to hand responsibility for separation to the helo pilot,

Well, that's interesting. You seem to be saying that "the system" worked as designed? FDR notes immediately before your reply:

Originally Posted by fdr

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.

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.