[jjwiseman]

There are non-radar towers that don't have scopes. They may have a traffic display, or maybe not. They might choose to use a public ADS-B aggregator site because it gives them situational awareness, but they don't use it to provide radar services to aircraft. That's my understanding from listening to a lot podcast episodes with air traffic controllers, anyway. I think it's an unofficial, non-FAA approved kind of thing that can make their jobs easier.

See https://www.faa.gov/air_traffic/publications/atpubs/atc_html... for non-radar ATC procedures.

[rootusrootus]

> They might choose to use a public ADS-B aggregator site because it gives them situational awareness

I do not understand what the upside is, aside from saving a tiny amount of effort and cost -- they could get the same data with more reliability by just running their own ADS-B receiver, without having a dependency on a third-party.

[mschuster91]

> they could get the same data with more reliability by just running their own ADS-B receiver, without having a dependency on a third-party.

Setting up an ADS-B receiver is indeed very cheap. Less than 100$. That's what many people, both aviation enthusiasts and ham radio operators, do for fun.

The problem is, do that on an airport? You'll now need permits to install the antenna (needs to be covered in the lightning protection system and even if it's just a passive receiver probably someone needs to sign off on an antenna being added). Fire code means you'll need approval and specialized people to run the cable (you need to drill holes in fire walls). Maybe there's some law or regulation requiring approval or causing a paper trail (e.g. in Germany, all electrical appliances have to be isolation-tested and visually inspected every two years by an electrician). Doing that the proper way is an awful lot of work. And by that point, someone will notice "hey, a Raspberry Pi? An RTL-SDR stick from eBay? No way that is certified to be used in a safety critical environment", killing off the project or requiring a certified device costing orders of magnitude more money.

In contrast, a privately owned laptop, tablet or phone with the Flightaware app? No one will give a shit about it unless someone relies on FA too much, causes an incident and that is found out.

[fy20]

I'd assume it's more to see "whats the latest ETA for this aircraft that's scheduled for 1 hour?". Their own ADS-B receiver is unlikely to pick it up.

[TeMPOraL]

Upside may be just that the equivalent first-party system doesn't exist or performs worse? ATC tower isn't a SCIF, they probably get their real-time news from Twitter like everyone else, too.

[blitzar]

> they could get the same data

They could get uncensored data too - you dont want billionaires jets crashing into other planes because they didnt want to be tracked.

[jjwiseman]

Imagine your boss doesn’t like you looking at ADS-B sites because it’s not data from an FAA approved system but as long as you’re discreet and not actually breaking a reg they don’t yell at you. Then they come in and see that you installed an antenna, RTL-SDR, and raspberry pi in the tower.