AA5342 Down DCA

[MPN11]

Originally Posted by jumpseater

Did you have, or need a radar based qualification to do that?

A UK Tower/LC can’t give headings unless they are radar qualified and current, and have the appropriate equipment.

That is a question I posed way back. Does DCA Tower have a slaved radar display? Does a non-trained/qualified controller have the authority to use that data in extremis? Personally, as an ATCO, and presented with imminently co-altitude and virtually head-on conflicting traffic, I would have intervened. But then I was always an interventionist Tower controller!

My earlier questions remain unanswered … does DCA Tower have a slaved radar display?
And thus could Tower have used that data to direct PAT21 out of the way, regardless of qualification or licensing? Or did Tower have a Radar qualification anyway, but didn’t use it?

[WHBM]

Originally Posted by Lonewolf_50

The right turn does not make sense.

If the guess that PAT25 saw the traffic for 01 (further south,who was #2 for landing, with the CRJ being #1) and not the traffic for 33, they were still advised by ATC to pass behind their traffic.

There were a number of aircraft around in the dark, which makes repeated unqualified reference just to "the CRJ" quite liable to error. I still wonder if the "Can you see the CRJ ... pass behind the CRJ" was being interpreted as the aircraft on the ground lining up on 01, the nearest aircraft to them and just on their right. They could see it, and they turned to pass behind it.

[island_airphoto]

Originally Posted by WHBM

There were a number of aircraft around in the dark, which makes repeated unqualified reference just to "the CRJ" quite liable to error. I still wonder if the "Can you see the CRJ ... pass behind the CRJ" was being interpreted as the aircraft on the ground lining up on 01, the nearest aircraft to them and just on their right. They could see it, and they turned to pass behind it.

I have been asked to blink my landing lights and asked others too. Otherwise a C-172 about to hit me, a C-5 a long way off, and Venus are all about the same. Helicopters with the running lights about 6 feet apart are the worst, they end up looking like an airplane a lot further away.

[skwdenyer]

Originally Posted by fdr

?.

Was there a change to the definition of VHF and UHF that we didn't get the memo on?

Our own versions of the 60 have needs for VHF along with FM, UHF and HF, secure or not. Presumably the USA doesn't use an ICOM A23 or similar when dropping in to some towns local airstrip. ARC-231"s? using a UHF freq when mixing with civil traffic would be self limiting, presumably the tapes will indicate the helo was on VHF freq not the UHF one.

The ITU definition of UHF is 300MHz to 3GHz. Hence I this wasn’t UHF.

It seems that radio marketers do call 257.6 MHz UHF. Go figure

[ATC Watcher]

Originally Posted by MPN11

That is a question I posed way back. Does DCA Tower have a slaved radar display?

I do not know , what kind and how it is used. Some US controllers said in another forum they now have one , but what is it , where it is located and what the procedures are I do not know. Normally at large airports you have a radar picture repeater for situation awareness not for providing radar control unless you are in a TWR-APP combined facility of course , but DC is not.
and

Does a non-trained/qualified controller have the authority to use that data in extremis?

if you mean in emergency , to prevent a collision ? , yes absolutely because in legal terms you always have the duty of care That is what the judge will come back to in the end. Now that said, where was the display located ? remember the guy was working 2 positions at same time . If there was a radar repeater display somewhere , was it located at the position he was working from ? The NTSB investigation will tell us that
.
If you are a controller you know how we work , Problem identified , = Conflict with PT detected , solution found = delegate separation , delegation accepted = problem solved. Next ... The guy was quite busy with departing and arrival traffic in runway one . Now of course with hindsight ,, what he should, and could perhaps have done is very easy for us to say . Feel very sorry for the guy . I hope he is not made the scapegoat for this mess.

[Senior Controller]

Originally Posted by skwdenyer

The ITU definition of UHF is 300MHz to 3GHz. Hence I this wasn’t UHF.

It seems that radio marketers do call 257.6 MHz UHF. Go figure

Easy to figure : just google it before asking : The military aircraft band in the 225-400 MHz range1. The frequency range for UHF is 225.0-399.975 MHz in 7000 channels (20 presets & 1 guard)

[spornrad]

Originally Posted by WHBM

There were a number of aircraft around in the dark, which makes repeated unqualified reference just to "the CRJ" quite liable to error. I still wonder if the "Can you see the CRJ ... pass behind the CRJ" was being interpreted as the aircraft on the ground lining up on 01, the nearest aircraft to them and just on their right. They could see it, and they turned to pass behind it.

Unlikely. The helicopter crew was told about the CRJ approaching 33. At the moment of that initial traffic advisory it meant, the CRJ would first cross their flight path from right to left, and then later on final (circle to land) from left to right. Did they simply expect still the former, seeing the second jet approaching 01, misjudging the timing / distance as to the CRJ, and therefore turning right to pass behind / give way to an approaching aircraft espected to turn any moment and cross their path from right to left?

[Suzeman]

Thanks for the info Radlettrejoin

[JRBarrett]

Originally Posted by MPN11

That is a question I posed way back. Does DCA Tower have a slaved radar display? Does a non-trained/qualified controller have the authority to use that data in extremis? Personally, as an ATCO, and presented with imminently co-altitude and virtually head-on conflicting traffic, I would have intervened. But then I was always an interventionist Tower controller!

My earlier questions remain unanswered … does DCA Tower have a slaved radar display?
And thus could Tower have used that data to direct PAT21 out of the way, regardless of qualification or licensing? Or did Tower have a Radar qualification anyway, but didn’t use it?

I can’t speak for DCA, but my local Class D airport (KELM) has had a radar repeater in the tower cab since the late 1980s, and all the local controllers use it. I would think DCA almost certainly has one. The radar repeater is not used to give vectors to aircraft, but as an aid to the controller’s situational awareness.

[GroundedDinosaur]

Altimeter setting vs Altimeter error amount?

The Helicopter wasn't landing at DCA, but, most likely would have the airports barometric setting in it's altimeter? If it was off by 0.2 inches, that would be about 200 ft?
I assume the altitude reading that the Altimeter in the aircraft displays in the cockpit is identical to the Transponded signal that ATC shows on it's screen? Is there a chance
that the Helicopter would have a different altimeter setting set? A new ATIS came out recently, or a pressure front was moving in?

[adnoid]

Drone footage of wreckage in the river

Posted today by NTSB:

You Tube

[Jetstream67]

Originally Posted by GroundedDinosaur

The Helicopter wasn't landing at DCA, but, most likely would have the airports barometric setting in it's altimeter? If it was off by 0.2 inches, that would be about 200 ft?
I assume the altitude reading that the Altimeter in the aircraft displays in the cockpit is identical to the Transponded signal that ATC shows on it's screen? Is there a chance
that the Helicopter would have a different altimeter setting set? A new ATIS came out recently, or a pressure front was moving in?

I'm not sure this is the key point here. 100ft vertical separation at 150 Knots +/- equipment error in any safety plan is going to go wrong one day.
Although the route / approach crossed the main plan was surely to never let two aircraft on different courses /stages get even 10 times that close in passing . . which takes us back to the real issue

[YRP]

Originally Posted by Undertow

They'd already said "Tower, we had an RA. Brickyard 4514 is going around" and that was acknowledged. They were then switched to Potomac who confirmed radar contact and asked reason for go around again. I would hope Potomac had seen/heard the "CA". But then after this everyone just carries on as if this is all perfectly normal until we all know what happened the very next day.

Potomac Approach is not in the same building (or at least room) as the Tower controller.

He’s asking the reason to find out what the a/c wants: sequence for another approach, divert due weather, hold to work out a technical fault.

Tower could have passed it on the hotline but it is probably normally more efficient to just have the a/c say.


Working about the safety implication of why the RA and what it says about the procedure is not something for the radio.

[DIBO]

Originally Posted by spornrad

Unlikely. The helicopter crew was told about the CRJ approaching 33. At the moment of that initial traffic advisory it meant, the CRJ would first cross their flight path from right to left, and then later on final (circle to land) from left to right. Did they simply expect still the former, seeing the second jet, misjudging the timing / distance as to the CRJ, and therefore turning right to pass behind / give way to an approaching aircraft espected to cross their path from right to left?

If people (and even 'reliable Youtubers') would stick to the available facts, instead of complicating things
No crossing of 'Route 4' prior to ...

[DIBO]

Originally Posted by YRP

Tower could have passed it on the hotline but it is probably normally more efficient to just have the a/c say.

Efficient? I call that sloppy...

[Undertow]

Originally Posted by YRP

Potomac Approach is not in the same building (or at least room) as the Tower controller.

Working about the safety implication of why the RA and what it says about the procedure is not something for the radio.

Seems it was not something for anywhere not just the radio. That was the problem.

[framer]

Either way, the controller does not have enough information to use a heading — neither to know one is needed nor what it should be .

I have never flown in the United States so am not sure, but if this was Australia the controller couldn’t give the helicopter a vector while it is below the minimum vectoring altitude anyway. I would be surprised if the controller in DC was able to legally issue a heading instruction to the Blackhawk while it is at or below 200ft at night. Can one of the American readers correct me if I am wrong?
​​​​​​​Thanks

[DIBO]

Originally Posted by framer

I have never flown in the United States so am not sure, but if this was Australia the controller couldn’t give the helicopter a vector while it is below the minimum vectoring altitude anyway. I would be surprised if the controller in DC was able to legally issue a heading instruction to the Blackhawk while it is at or below 200ft at night. Can one of the American readers correct me if I am wrong?
Thanks

not an American readers, but was thinking the same couple of days ago, so I found this:

Vector aircraft: At or above the MVA or the minimum IFR altitude except as authorized for radar approaches, radar departures, special VFR, VFR operations, or by paragraph 5-6-3, Vectors Below Minimum Altitude.

https://www.faa.gov/air_traffic/publ...section_6.html

​​​​​​​

[DIBO]

VHF, UHF, .... the important fact is that pilots were on different frequencies...whatever spectrum band they were on, is less relevant.

But for those rebuking any mentioning of a VHF Heli frequency, please provide some proof as any reference I find on VFR sectionals, is a VHF Heli-frequency.
IFR charts only have the regular VHF+UHF TWR freq.

[MikeSnow]

Originally Posted by DIBO

If people (and even 'reliable Youtubers') would stick to the available facts, instead of complicating things
No crossing of 'Route 4' prior to ...

Still, if the helo crew misidentified the A319 as the CRJ, and they assumed the A319 will start turning right soon to circle for 33, turning right as well would have increased horizontal separation. And the extended centerline for 01, which the A319 was aligning with, does actually intersect with Route 4 a bit after the Wilson Bridge. And, looking at the radar replay, the A319 did actually turn right for a bit, to align to 01. At around the same time, the helo starts turning right.

You Tube

I agree that these are just guesses, but the alternative seems to be that the helo just drifted to the right randomly, for no specific reason, which seems unlikely.