6 ms·

Here is the ATC audio between the Tower and PAT-25. Helos that transition DCA's airspace use a separate VHF frequency from traffic landing and departing, but t

Here is the ATC audio between the Tower and PAT-25. Helos that transition DCA's airspace use a separate VHF frequency from traffic landing and departing, but talk to the same tower controller. https://archives.broadcastify.com/44114/20250129/202501292000-281903-44114.mp3 https://archives.broadcastify.com/44114/20250129/20250129200... * At 5:41 - 5342 is given instructions for circling to 33. * At 6:45 - PAT-25 reports Memorial * At 7:06 - tower gives PAT-25 traffic advisory about 5342 and PAT-25 reports traffic in sight and requests visual separation * At 8:12 - tower asks PAT-25 if they have the CRJ in sight and tells him to pass behind the CRJ. PAT-25 again reports traffic in sight and again requests visual separation. * At 8:28 - crash occurs, exclamations, go arounds issued

fblp 2y ago
This is wild to listen to. A) this is a busy atc channel and it's amazing how much complexity is coordinated over noisy radio. B) within minutes of the accident happening (at 11:48) the ATC controller is calmly asking helicopters in the air if they can assist in search rescue operations asking, if they have search lights and direction them. This is whilst diverting and grounding flights.
- consp 2y ago
  > over noisy radio I've been told the noise on the recordings is always a lot worse than in practice due to the location of the recording antenna not being ideal. I have no idea if this is correct or not. Maybe someone can enlighten this.
  - thowawatp302 2y ago
    Yes, having tried to listen to ATC with an SDR— the public recordings are made from antenna that placed near the airport, while the official recordings are made from the feeds that the ATC is listening to— and those antenna have their lobes pointed toward the sky.
  - FL410 2y ago
    Yep. Radios are much clearer in the air. VHF is mostly line of sight and planes have the benefit of altitude. Approach/center comms can get a bit scratchy at times mostly due to distance, but approach/tower is almost always perfectly clear.
  - jillesvangurp 2y ago
    I watch a lot of pilots on Youtube. Most of them use some kind of audio splitter to record sound. You hear what the pilot hears. But minus the plane noise, vibrations, etc (unless that's mixed in via some open microphone). So, it's actually better. So, it really is that bad. Especially when flying low, on the edge of the range of the radios, etc. VHF radio is ancient technology. It's not great even under ideal conditions. If your phone calls sounded that bad, you'd want to upgrade your phone or switch operator. Really not acceptable for consumer grade communication. Not even close. This is how phones sounded half a century ago. "can you hear me .... are you there ..... can you talk louder ....". My grand mother never really unlearned 1930s phone etiquette. Phone calls with her were short (cause expensive) and she'd be shouting at you because that's what you did. Be brief, loud, hang up as soon as possible. That's what pilots still do. My grand mother was born during WW I (not II) and she's been dead for nearly 20 years. The aviation world is very conservative with new/better/any technology. They stick with "what works". Even if arguably it barely works. Like pretty much the vast majority of radio exchanges between pilots and controllers over VHF radio. Learning how to talk on the radio is the second hardest part of getting an instrument rating. The only thing that's harder is flying a plane with zero visibility ... while suffering extreme information overload because of the constant radio chatter and dealing with confused/stressed/pissed off controllers who have to juggle you and 20 other planes. A lot of radio exchanges are routine exchanges that involve very basic information: call signs, transponder codes, codes for approaches/departures, courses, altimeter settings, altitudes, weather information, etc. And then a lot of double checking the other side heard correctly, repeating back what you heard, etc. Radio communication compensates for the lack of a more robust/sane way of exchanging information. There literally is no way for a controller to send you information in written format. Other than using their private phones. So, it all gets spelled out over low quality VHF radio. There's no good technical reason to not do something vastly more reliable, less intrusive, and less error prone. Some might say safer. Many planes have star link connections these days. The passengers get better connectivity than the pilot. They could be having video calls with the controller with crystal clear audio from anywhere on this planet instead of yelling to them over VHF only when they are in range. They could be sending each other emails, documents, digital maps, and lots of other machine readable information, etc. Not a thing. It's more a challenge of agreeing on what such a vastly better thing would be and then updating each and every plane and tower, airport, controller world wide with equipment that supports that. Add design by committee to the mix and the "state of the art" is something that would make any competent engineer born after 1970 blush.
lawlessone 2y ago
I think the crash was at 8:22 or 8:21, you can hear sudden commotion at that time.

fblp 2y ago

This is wild to listen to. A) this is a busy atc channel and it's amazing how much complexity is coordinated over noisy radio. B) within minutes of the accident happening (at 11:48) the ATC controller is calmly asking helicopters in the air if they can assist in search rescue operations asking, if they have search lights and direction them. This is whilst diverting and grounding flights.

consp 2y ago
> over noisy radio I've been told the noise on the recordings is always a lot worse than in practice due to the location of the recording antenna not being ideal. I have no idea if this is correct or not. Maybe someone can enlighten this.
- thowawatp302 2y ago
  Yes, having tried to listen to ATC with an SDR— the public recordings are made from antenna that placed near the airport, while the official recordings are made from the feeds that the ATC is listening to— and those antenna have their lobes pointed toward the sky.
- FL410 2y ago
  Yep. Radios are much clearer in the air. VHF is mostly line of sight and planes have the benefit of altitude. Approach/center comms can get a bit scratchy at times mostly due to distance, but approach/tower is almost always perfectly clear.
- jillesvangurp 2y ago
  I watch a lot of pilots on Youtube. Most of them use some kind of audio splitter to record sound. You hear what the pilot hears. But minus the plane noise, vibrations, etc (unless that's mixed in via some open microphone). So, it's actually better. So, it really is that bad. Especially when flying low, on the edge of the range of the radios, etc. VHF radio is ancient technology. It's not great even under ideal conditions. If your phone calls sounded that bad, you'd want to upgrade your phone or switch operator. Really not acceptable for consumer grade communication. Not even close. This is how phones sounded half a century ago. "can you hear me .... are you there ..... can you talk louder ....". My grand mother never really unlearned 1930s phone etiquette. Phone calls with her were short (cause expensive) and she'd be shouting at you because that's what you did. Be brief, loud, hang up as soon as possible. That's what pilots still do. My grand mother was born during WW I (not II) and she's been dead for nearly 20 years. The aviation world is very conservative with new/better/any technology. They stick with "what works". Even if arguably it barely works. Like pretty much the vast majority of radio exchanges between pilots and controllers over VHF radio. Learning how to talk on the radio is the second hardest part of getting an instrument rating. The only thing that's harder is flying a plane with zero visibility ... while suffering extreme information overload because of the constant radio chatter and dealing with confused/stressed/pissed off controllers who have to juggle you and 20 other planes. A lot of radio exchanges are routine exchanges that involve very basic information: call signs, transponder codes, codes for approaches/departures, courses, altimeter settings, altitudes, weather information, etc. And then a lot of double checking the other side heard correctly, repeating back what you heard, etc. Radio communication compensates for the lack of a more robust/sane way of exchanging information. There literally is no way for a controller to send you information in written format. Other than using their private phones. So, it all gets spelled out over low quality VHF radio. There's no good technical reason to not do something vastly more reliable, less intrusive, and less error prone. Some might say safer. Many planes have star link connections these days. The passengers get better connectivity than the pilot. They could be having video calls with the controller with crystal clear audio from anywhere on this planet instead of yelling to them over VHF only when they are in range. They could be sending each other emails, documents, digital maps, and lots of other machine readable information, etc. Not a thing. It's more a challenge of agreeing on what such a vastly better thing would be and then updating each and every plane and tower, airport, controller world wide with equipment that supports that. Add design by committee to the mix and the "state of the art" is something that would make any competent engineer born after 1970 blush.

lawlessone 2y ago

I think the crash was at 8:22 or 8:21, you can hear sudden commotion at that time.