Two planes taking off from National put on collision course with plane trying to land

[SeenItAll]

Putting this in the ATC forum because looking for a professional answer. Feel free to relocate to Spotters if inappropriate.

Evidently, in "turning the airport," Tower ATC didn't complete/redirect all approaches before launching planes in the new direction. Recognizing that this process is always complex, is a screw-up like this at a major airport something that (a) pretty much never happens; or (b) happens once every few years; or (b) more frequently? Thanks.

Two planes taking off from National put on collision course with plane trying to land - The Washington Post (http://www.washingtonpost.com/local/trafficandcommuting/two-planes-taking-off-from-national-put-on-collision-course-with-plane-trying-to-land/2012/08/01/gJQAxxPSQX_story.html)

[whitelighter]

Virtually unheard of over here.

Don't know about over there mind.

[SeenItAll]

I would hope it is close to unknown here, too. What I am taken by is that if you listen to the ATC audio link in the newspaper article (legal in the US :O), the controller seems pretty nonchalant in telling Brickyard 3329 to head 180 (pretty much making a 180 turn from its established approach heading to RW 1). Either this is a lot of sang froid, or she didn't realize: The inbound plane and the first of the outbound planes were closing the 1.4 miles between them at a combined speed of 436 mph, a rate that meant they were about 12 seconds from impact when the tower controller recognized her mistake. Or, possibly, the article is wrong about close they were.

[Ditchdigger]

I would hope it is close to unknown here, too. What I am taken by is that if you listen to the ATC audio link in the newspaper article (legal in the US
http://images.ibsrv.net/ibsrv/res/src:www.pprune.org/get/images/smilies/embarass.gif), the controller seems pretty nonchalant in telling Brickyard 3329 to head 180...


There has been some discussion of this on LiveATC: kdca tuesday | LiveATC.net (http://www.liveatc.net/forums/atcaviation-audio-clips/kdca-tuesday/)

As pointed out in post #3 of that thread, the audio archive of the incident time is only 24 minutes long, whereas usually those archives are 30 minutes in length.

I suspect that in the six minutes of audio apparently missing from the LiveATC archive there's some rather dramatic vectoring going on.

You'd also expect somebody to have reported a TCAS RA in such a situation, wouldn't you? If the recording is complete, why don't we hear that, either on LiveATC, or in the audio provided with the news story?




Quote:

...(pretty much making a 180 turn from its established approach heading to RW 1). Either this is a lot of sang froid, or she didn't realize:


The inbound plane and the first of the outbound planes were closing the 1.4 miles between them at a combined speed of 436 mph, a rate that meant they were about 12 seconds from impact when the tower controller recognized her mistake.

Or, possibly, the article is wrong about close they were.


Also linked in that post is the Flightaware track: FlightAware > Republic (RW) #3329 > 31-Jul-2012 > KPWM - KDCA Flight Tracker (http://flightaware.com/live/flight/RPA3329/history/20120731/1635Z/KPWM/KDCA)

I suspect the "nonchalant" heading of 180 was the latter turn to the south, after the initial avoidance manuvering.

I hate to suspect that something has been intentionally deleted there at LiveATC, but Occam is telling me otherwise...

[Plazbot]

NCD


___________________

[SeenItAll]

The FlightAware map seems off. Normal north approaches/departures are along the Potomac for about 10 miles to Cabin John, and to the south about 10 miles to Mount Vernon. This map shows a whole lot of vectoring within a far tighter radius (only 2 to 3 miles). If this is accurate, the sh_t must have really hit the fan.

Not sure whether there would have been TCAS alerts because it may have been inhibited on landings/take-offs -- and because ascent/descent vectors may be sufficiently extreme during that phase so software extrapolations may have been inaccurate.

[chevvron]

I've observed it twice at Heathrow.
First time was about 30 years ago; Heathrow switched from westerly to easterly; on radar we watched the stream of traffic positioning downwind for easterly landing, then an aircraft appeared westerly off Heathrow and every aircraft in the inbound pattern from both north stacks and south stacks (about 14 or more in total) did an orbit. No danger.

The second time was a few weeks ago. I was in my back garden and aware of MID departures from runway 27s passing overhead, then noticed aircraft positioning downwind for 09s; just after the first ones passed, another 27 MID departure passed overhead.
No danger that I could see, but I don't have access to radar any more so I couldn't see their altitudes.

[Ditchdigger]

Not sure whether there would have been TCAS alerts because it may have been
inhibited on landings/take-offs -- and because ascent/descent vectors may be
sufficiently extreme during that phase so software extrapolations may have been
inaccurate.


Could be. Followup media coverage does say that none of the aircraft had a TCAS alert. Followup stories also specify the separation between the three, and FAA's denial that a collision was imminent.

I mainly mentioned TCAS because there's an obvious discontinuity in the audio presented. (While the media uses soundbites of said audio to paint the picture of three aircraft careening towards one point in space, when it's actually audio of the conversations that took place after the conflict had been resolved.):rolleyes:

[Warped Factor]

chevvron wrote:

The second time was a few weeks ago. I was in my back garden and aware of MID departures from runway 27s passing overhead, then noticed aircraft positioning downwind for 09s; just after the first ones passed, another 27 MID departure passed overhead.
No danger that I could see, but I don't have access to radar any more so I couldn't see their altitudes.

Utter tosh.

Sums up much of the stuff you post here and on Flyer these days :rolleyes:

[chevvron]

So you're saying it didn't happen as I observed it; that the first 09 arrival wasn't turning onto base leg when the last MID departure from 27 was launched? That this never happens? That on a clear day I didn't see what I said?

[SeenItAll]

More detailed information and graphics now becoming available. Evidently initial story stating that conflicts were south of the airport by Mount Vernon was incorrect. Arriving plane was approaching from the northwest, and departures were from RW 1 to the north.

Given the tight vectoring of Brickyard 3329 (i.e., not starting his approach along the Potomac from Cabin John), it appears that he was anticipating an arrival on the slightly diagonal RW 15 rather than the reciprocal RW 19.

Congress, agencies investigating incident at Reagan National Airport - The Washington Post (http://www.washingtonpost.com/local/trafficandcommuting/congress-agencies-investigating-incident-at-reagan-national-airport/2012/08/01/gJQARsV5SX_story.html)

[Warped Factor]

What you saw from the vantage point of your back garden was a routine runway change.

To suggest here it was some sort of incident based on observations from a back garden, utter tosh.

[chevvron]

You're the one claiming it was an incident not me, in fact I clearly said 'no danger', I was merely commenting that crossovers DO sometimes occur on runway changes, especially somewhere as busy as Heathrow.

[Duke of Burgundy]

chevvron - I'm not sure of the point of your original post other than to imply something untoward. You might, however, be interested to read this.

http://www.airproxboard.org.uk/docs/423/20120620201206Reports.pdf

Report No. 2012026 pp32-39

[Warped Factor]

You're the one claiming it was an incident not me, in fact I clearly said 'no danger', I was merely commenting that crossovers DO sometimes occur on runway changes, especially somewhere as busy as Heathrow.

You opened your first post with "I've observed it twice at Heathrow." Observed what twice if not implying that you've observed some sort of incident twice. That's what this thread is about after all, an incident during a runway change.

You then introduce two totally irrelevant examples including one observation from, of all places, your back garden that included the phrase "no danger that I could see". Well thank goodness for that.

I don't believe you've ever worked at Heathrow, the airport you cited in your examples. If you had you would have noticed that pretty much every time they change ends the first arrivals to the new runway will "cross over" the last departures from the old. That's how it works.

:rolleyes:

[ZOOKER]

Hmm, runway changes, and the numerous hazards associated therewith.
You slice the Swiss cheese, and I'll wind up the clockwork mouse.

[sevenstrokeroll]

I don't think the landing traffic was going to runway 15 at all.

I think ATC screwed up and forgot about the traffic inbound to runway 19.

ps...based at DCA for over 10 years flying jets there.

AS to tCAS...certain audio alerts/RA's may hve been inhibited due to altitude, however TA or just seeing targets on the TCAS display may have been helpful.