Plane Crash In DC

smartcooky said:
Flying along, confident that you are at 200 ft (because your altimeter says so) and not realizing that you are actually at between 280 and 330ft, putting you right in the flight path of approaching aircraft.
That is an error between 40% and 65%. 😳
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...with a night-vision hood on. In some of the most congested airspace in the United States. I'm watching the hearing live now. NTSB is grilling the FAA technical witnesses about just how badly organized the DCA airspace and control is.
 
I'm assuming these are radar altimeters they are talking about, yes?
Well, I used to maintain, repair and calibrate the radar altimeters on our C-130s, AN/APN 133 and AN/APN150 - a high altitude radar altimeter and a low altitude one (there is a reason why there are two). We had a required accuracy of ±5 ft or ±5% of the reading, whichever is the greater.
 
smartcooky said:
Flying along, confident that you are at 200 ft (because your altimeter says so) and not realizing that you are actually at between 280 and 330ft, putting you right in the flight path of approaching aircraft.
That is an error between 40% and 65%. 😳
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Insane.

From the linked story:
Army officials at the hearing said that discrepancies of up to 100ft were not a cause for alarm in the helicopter because pilots are expected to maintain their altitude plus or minus 100 ft.
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How does that work if you are flying at 100 ft?

Of course we know how it works if you are flying at 300 ft but think you are flying at 200..
 
smartcooky said:
Flying along, confident that you are at 200 ft (because your altimeter says so) and not realizing that you are actually at between 280 and 330ft, putting you right in the flight path of approaching aircraft.
That is an error between 40% and 65%. 😳
Click to expand...
What scares me, really scares me -- and I once served as an assistant crew chief on US Army UH-1H helicopters -- is the idea that even 80-130 vertical feet is adequate separation for a jet airliner and a helicopter when they're crossing one another's flight path. At night? When the flight crew on the airliner is busy making their final approach to their runway?

No thanks!!! :eye-poppi
 
newyorkguy said:
What scares me, really scares me -- and I once served as an assistant crew chief on US Army UH-1H helicopters -- is the idea that even 80-130 vertical feet is adequate separation for a jet airliner and a helicopter when they're crossing one another's flight path. At night? When the flight crew on the airliner is busy making their final approach to their runway?

No thanks!!! :eye-poppi
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Indeed.
The implications of this Route 4 corridor diagram scares the everloving crap out of me!
DCA-Route4-corridor.jpeg

ETA: Its even more frightening when you realise this is not to scale. In reality, that glide path is only 3°, not about 30° as depicted here.
 
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I gather they expect horizontal separation to be more important and that this is why the controller instructed the helicopter to pass behind the airliner rather than to ensure it was flying underneath. 75 feet vertical separation is effectively no separation.
 
Just been watching a playback of the hearing. OMG!!!

Jennifer Homendy of the NTSB has been ripping the FAA a new one. She has pointed out that they (the FAA) KNEW there were serious safety concerns at DCA, that their their own managers and employees at the DCA tower were repeatedly telling them about those safety issues, and the FAA's response was to move the complainers out to other jobs. This smacks of the same sorts of things that were going on at Boeing in the period leading up to the Max-8 crashes.

Here are her words on some of the issues (from the transcript)

Pulls up the witnesses for their unacceptable behaviour in using their devices to communicate with each other: "Mr. McKenna, can you hold for a second? I would ask that witnesses put away their electronic devices. If you are communicating with your party tables, you should not be doing that. Please put them away."

Berating one of the FAA representatives: "The sign was there that there was a safety risk and the tower was telling you that. You know what FAA did after the accident occurred? You transferred out the air traffic manager, two general assistant general managers and the staff support manager. What you did is you transferred people out instead of taking ownership over the fact that everybody in FAA in the tower was saying there was a problem. But you guys are pointing out, well, our bureaucratic process, somebody should have brought it up at some other symposium. Are you kidding me? 67 people are dead. How do you explain that? Our bureaucratic process was how many steps it takes to get a policy change. 21steps. Fix it. Do better!!"

Berating FAA behaviour in general: "So, it looks like somebody was spotted trying to interfere with the speaker. Uh, I had noticed that one, not
just me, me, members in the audience, NTSB staff and members on watching virtually had all reported that one of the supervisors had elbowed an FAA employee mid sentence. I'm not going to make an assumption about that, but that person had stopped speaking as a result. We want people to be fully transparent and feel safe in providing us answers. So, we're going to switch the panelists. I'm not going to put up with that. Okay?"

This NTSB chairwoman is running a tight ship, and she ain't taking any â—Šâ—Šâ—Šâ—Š!
 
JayUtah said:
I gather they expect horizontal separation to be more important and that this is why the controller instructed the helicopter to pass behind the airliner rather than to ensure it was flying underneath. 75 feet vertical separation is effectively no separation.
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This is hardly surprising considering that in all general aviation, any time two aircraft come within 500 feet of each other, it is considered to be an NMAC (Near Mid-Air Collision), usually known as a near-miss.
 
Here is a short interview with Tim Lilley, father of one of the Bombardier CRJ701 pilots.

Tim is a pilot himself, and has flown CRJ701 in and out of DCA, as well as the UH60 on these DCA helicopter routes, so he is uniquely qualified to speak on this accident and the NTSB hearings.

 
He says it used to be the case that helicopters couldn't fly Route 4 when an airliner was on approach to R33. That seems intuitively prudent. It would be nice to investigate how we went from that to approving see-and-avoid visual deconfliction. Given the pressure to increase VIP flights and increase throughput at DCA, the likely answer seems to be the normalization of risk.

Also I think we missed this (PDF), which happened back in March and seems to alleviate things in the short term. It deletes Route 4 and another route.
 
Secretary Sean Duffy

@SecDuffy
·
20h
These are a few pictures of the outdated equipment I saw during my tour of an air traffic control tower.

I’m getting rid of this and building a brand new system with the money from
@POTUS
’ One Big Beautiful Bill.

America deserves the best and most advanced technology for its citizens when they travel!

https://twitter.com/x/status/1954226467434295362
 
The NTSB opposes Section 373 of the proposed NDAA currently before the House. They argue that it reverses critical aviation safety measures implemented after the January 29 fatal mid-air collision near DCA. The head of the NTSB is extremely pissed off with politicians right now, and as always, speaks her mind in spades!!



I think the â—Šâ—Šâ—Šâ—Š is going to hit the fan, and soon.
 
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