Comment by throw0101d | Hacker News Reader

Comment by throw0101d | Hacker News Reader

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> Could the accident be linked to the clarity of radio instructions? I saw a discussion suggesting the DH aircraft might have been unsure about the correct runway to use, C1 or C5.

From my comment in part of the discussion thread[0]:

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For the ATC, see:

* https://archive.liveatc.net/rjtt/RJTT-Twr-TCA-Jan-02-2024-08...

* Via: https://www.flyertalk.com/forum/35868205-post57.html

13:13 JL516 continue approach. 14:53 landing clearance. 15:01 readback. 15:13 Japan Coast Guard JA772A taxi instructions. 17:35 fire reported on 34R.

* https://www.flyertalk.com/forum/35868237-post67.html

The recording quality isn't very good, perhaps because of the location of the receiver.

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The ATC quality of my local airport (CYYZ Tower) available through LiveATC is much better. I following some flying/pilot Youtubers, and their recordings of ATC are also quite good, so I'm not sure why LiveATC at HND is as statically as it is.

[0] https://news.ycombinator.com/item?id=38839885#unv_38841161

All of these ATC feeds are from SDR stations close by that monitor the same frequencies. Your local airport sounds better because someone has a better SDR rig to receive it. Generally the audio is crystal clear in the cockpit and on the ground — it’s just that the SDR stations don’t have as good antennae as the real systems do.

I’ve always wondered about that. When I hear recordings online they’re often so bad I wonder how there aren’t more issues.

That explains it.

I know it’ll be a long time coming but wait for the ATC recordings to come out. They’ll be crystal clear.

Yep, it's a line-of-sight transmission, so in a way the aircraft has the advantage of being a really, really tall antenna.

The volunteers running the feeds around YYZ are at the airport, IIRC. I'm in Halifax now, and the (single) YHZ feeder has had a really hard time finding a new place to set up after he lost his previous location.

There's a "feed setups" thread (or a whole forum) in the LiveATC forums, it's interesting to see how big or small the feeders' setups are!

Antenna quality is unlikely to be a significant factor in audio quality if the stations are actually somewhat close to the airport. The difference between a very good and very poor antenna is maybe 5-7 dB in the VHF airband, which shouldnt noticeably degrade quality unless you are already at the margins of signal availability. Antenna location is going to make a much, much bigger difference.

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