Bizarre: Flights Receive False Collision Alerts At DCA Airport

Bizarre: Flights Receive False Collision Alerts At DCA Airport

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There’s certainly some anxiety regarding the airspace around Washington National Airport (DCA), given the fatal mid-air collision we saw several weeks back, which claimed 67 lives. Along those lines, it was an unusual weekend at the airport, as several planes reported receiving collision warnings, despite no traffic being around.

Erroneous TCAS alerts at Washington DCA Airport

On Saturday, March 1, 2025, several aircraft landing at Washington National Airport received TCAS alerts while on approach.

For those not familiar, commercial aircraft are equipped with TCAS (Traffic Collision Avoidance System), which is supposed to help pilots avoid midair collisions. These alerts come in the form of either TAs (Traffic Advisories), which alert pilots of other planes nearby, or RAs (Resolution Advisories), which give specific instructions about which action pilots should take.

TCAS saves lives, and in most situations, helps avoid any potential midair collisions. But this is also where the situation gets strange, because on Saturday, several aircraft on approach to DCA received TCAS warnings. The good news and bad news is that there weren’t actually any traffic conflicts. That’s good because it means there was no danger, but it’s bad, because it means that something strange was going on.

VASAviation has an excellent video with many of the reports from pilots. One pilot with a TCAS alert said “there was something diving straight onto us,” while another pilot said “it appeared that the target was 600 feet above us.”

Later on, pilots can be heard chiming in with comments like “aliens” and “Russia.” Hah. You can watch the video for yourself below, showing the location of aircraft, plus the air traffic control audio.

The FAA is now investigating this odd TCAS situation

The Federal Aviation Administration (FAA) is now investigating this incident, and has released the following statement:

“Several flight crews inbound to Reagan Washington National Airport received onboard alerts Saturday indicating another aircraft was nearby when no other aircraft were in the area. Some of the crews executed go-arounds as a result of the alerts. The FAA is investigating why the alerts occurred.”

One certainly wonders what could be causing repeated false TCAS alerts, since that’s not something you want to happen, for obvious reasons.

ABC7 interviewed an airline pilot of 40 years about the possible causes, who provided the following insights:

“So there’s only three things I think that could cause it to go off. First is another airplane. The idea that it wasn’t another aircraft leaves it up to the other two, which is either a flock of birds, which is very unlikely, or something on the ground that was transmitting that was causing an erroneous signal that caught several of these airplanes in a row.”

Meanwhile a commenter on VASAviation wrote the following, which is probably a more technical explanation of that last point above:

“This can happen if an ADSB system on the ground is not filtering ‘ownship’ traffic properly. Had this happen near KCOS airport (Colorado Springs) a year ago. The consistency tells me it is the same thing. If you understand how this system works, it is clear what happens when filtering from the ground stations are not done properly. On board equipment interprets your ship as a separate target, unknown, and right on top of you.”

This is way beyond my area of expertise, though it’s pretty remarkable that this is happening at the same airport where a mid-air collision happened just weeks ago. Is that a coincidence, or…?

Bottom line

On Saturday, several aircraft on approach to Washington DCA reported receiving TCAS alerts, despite there being no traffic in sight. The FAA is now investigating the cause of this, since it’s of course important to minimize the number of false TCAS alerts, given that TCAS is basically the last defense against collisions.

What do you make of this strange TCAS alert situation at DCA?

Conversations (19)
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  1. omarsidd Member

    Question is was this before or after the "doge" crew plugged into the ground systems.

  2. JayC Member

    Why does it feel like we are having more flight incidents lately? some fatal and some not, but still, a lot of flight incidents than "usual"

  3. JPlat Guest

    This is another evidence that non-US allies are trying to sabotage Trump and Musk's US. We now have generational visionary leadership and the other countries are clearly jealous of us. Ukraine just recently visited and then this happened, it is clear that Europe, UK, and even our closest neighbour Canada are trying very hard to cause these false signals to create more problems for us.
    The sooner we conquer Canada and Russia conquer and...

    This is another evidence that non-US allies are trying to sabotage Trump and Musk's US. We now have generational visionary leadership and the other countries are clearly jealous of us. Ukraine just recently visited and then this happened, it is clear that Europe, UK, and even our closest neighbour Canada are trying very hard to cause these false signals to create more problems for us.
    The sooner we conquer Canada and Russia conquer and rule Europe, the safer it will be for the US and our people.
    Trump is not allowed a 3rd term, but it's good that we have Musk in the background to assist with the transition from Trump senior to the next generation.

    1. NW Guest

      Sadly, having noticed JPlat's previous comments, I don't believe it's an attempt at satire but unfortunately not majority but a large enough part of how a lot of America thinks now.
      Looking at the appointments and "loud" supporters of Musk's America now, I guess a civilisation needs to fall somehow.

    2. James Guest

      @NW it's bonkers. The idea that because something odd is going on with Washington airport, that it follows it must be Ukraine or Canada or Europe's fault or all three and as such they all need to be conquered is wild and a bit deranged. There is zero "evidence" any of these nations are behind something which, as the post has pointed out, is likely just a glitch - despite the illogical protestations of @jplat

  4. George Romey Guest

    It's believed it may have been a small drone, which would have been difficult to see. Not Donald Trump.

  5. Ben L. Diamond

    So happy that the planned systems upgrade that was awarded to a vendor through a deliberative and transparent procurement process is being swiftly supplanted by a different vendor owned by a drug-addicted presidential crony whose electric vehicles have been plagued by massive safety and reliability defects.

    1. Ben L. Diamond

      Incidentally, the same crony who illegally fired a bunch of air safety personnel before taking to the social media platform he tanked to beg retired personnel to return!

  6. Maryland Guest

    Probably an adjustment from the new instruction that air traffic at DCA must halt every time the president is moved. So yeah, it's Russia

  7. Arghh Me Matey Guest

    It’s the ghost of the PSA flight

  8. BZ Guest

    Vote for Russia, become Russia.

    Good luck America.

  9. lavanderialarry Guest

    American ingenuity, know-how, and superiority everywhere since inauguration day.

    1. David Guest

      Yes, it's getting better. Unfortunately, not even a great man like Trump can fix the damage caused in the last four years in only a few months.

    2. Ern Guest

      Yeah the eggs are $8 instead of $4. So much better.

    3. Dulles Doldrums Guest

      How's that full detachment from reality treating you, David?

    4. David Guest

      First as IAD is my home airport, I like your name.

      Second, the reality is the man has been in office a little over a month; he can't change the world in that short period of time. The reality is he won the election, and he deserves at least six months to fix the mess he inherited.

    5. mintyfreshapples Guest

      Yay, another foaming at the mouth rabid MAGA moron here. Y'all are savages.

Featured Comments Most helpful comments ( as chosen by the OMAAT community ).

The comments on this page have not been provided, reviewed, approved or otherwise endorsed by any advertiser, and it is not an advertiser's responsibility to ensure posts and/or questions are answered.

James Guest

Is this satire?

3
David Guest

First as IAD is my home airport, I like your name. Second, the reality is the man has been in office a little over a month; he can't change the world in that short period of time. The reality is he won the election, and he deserves at least six months to fix the mess he inherited.

1
Ern Guest

Yeah the eggs are $8 instead of $4. So much better.

1
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