Midair collision between Helicopter and CRJ (AA5342) at Washington (DCA)

[justinbrett]

It was, but it also had lateral movement at the time, which makes it no threat, whilst the other aircraft on finals had a constant bearing. I don't think that there's much doubt that they never locked on to the dangerous aircraft.

From what I understand about flying with goggles, you have to be careful about head movements, as they can be disorienting, so the normal head movements that a pilot might make to keep things in sight, may not be advisable. Of course that then puts us to a question of whether these goggles should really allow an aircraft to fly VFR, if they limit the ability to maintain visual separation.

Ah, but that wouldn't be convenient.

They shouldn't have accepted (or offered) pilot visual separation wearing NVGs. Perhaps this is the crux of the issue.

The simulation was clearer than I expected. Absolutely can see how the two inbound aircraft can be initially confused (hell, I've seen a tower controller confuse an aircraft with a star), but in closer range, especially at the time of the second traffic call, I would expect any VFR pilot (rated for night) to accurately spot the CRJ. At least with a controller who can make decent traffic calls.

 

[jb747]

They shouldn't have accepted (or offered) pilot visual separation wearing NVGs. Perhaps this is the crux of the issue.

It's certainly an issue that has to be resolved. The military do accept operations with reduced safety, as a matter of course. But, their standards should never end up being applied to civilian aircraft.

The simulation was clearer than I expected. Absolutely can see how the two inbound aircraft can be initially confused (hell, I've seen a tower controller confuse an aircraft with a star), but in closer range, especially at the time of the second traffic call, I would expect any VFR pilot (rated for night) to accurately spot the CRJ. At least with a controller who can make decent traffic calls.

The CRJ, for whatever reason, and contrary to what we might expect, was not seen. To be honest, I'm surprised this doesn't happen more often. It's quite amazing how hard it can be sometimes, to see aircraft, even when they are literally being pointed out to you. We see it here because we are looking for that second aircraft, and know where to look. And, we aren't wearing goggles. Something else that might have some relevance, is that of focus. We're looking at a 3d screen, a fixed distance away. That's not the case in flight, and I don't know how goggles will affect that.

So, could they have seen the CRJ? Yes, it would seem so. Did they see it? Obviously not. Sadly "could have" doesn't convert to a safe operation.

 

[justinbrett]

We see it here because we are looking for that second aircraft, and know where to look. And, we aren't wearing goggles.

And with a well constructed and delivered traffic call, so could the Blackhawk (sans goggles). The first traffic call was by the book, but delivered way too early. The second was non existent and just reconfirmed the previous error.

 

[elanshin]

I also wonder how frequently ATC would need to prioritise helicopter travel over airliners and even restricting landings if a VIP was travelling the route.

I have to imagine there are scenarios where they defer to and prioritise the helicopter along this corridor given the nature of the potential passengers on them.

 

[moa999]

The second was non existent and just reconfirmed the previous error.

Agreed. If the second communication had been CRJ at your 300 degrees, 400ft cleared to land on R33, the error may not have occured.

But particularly on that 33/ Route 4 crossing point where the vertical separation is likely to be pretty tight, it really should be more like a runway crossing where the helo is told to hold short at a particular point.