Telling ATC Traffic Identified on ADS-B

Updated 27 January 2017.

Yesterday, I published an article about what to say to ATC when you have identified traffic on your onboard ADS-B screen. Based on feedback from several air traffic controllers, who all responded similarly, I’m going to change my recommendation.

Previously, I said when ATC points out traffic and you notice the traffic on your ADS-B screen, you may tell ATC, “[Call sign] has the traffic on ADS-B”. I also said, as an alternative, you may substitute “TIS-B” for “ADS-B”. This, as it turns out, was not good advice.

From Public domain photo.

ID-ing Traffic on ADS-B is Irrelevant to ATC Ops

Here’s the truth of the matter. The only thing an air traffic controller cares about is whether or not you spot the traffic through the windscreen of your aircraft. Noting the traffic on your ADS-B set or, if you have it, on your Traffic Collision Avoidance System (TCAS) does not affect ATC operations in any way.

If you spot the traffic through your windscreen, in some circumstances, the controller may apply traffic separation rules based on you maintaining visual contact with the traffic. Visual separation rules cannot be applied under any circumstance if you can’t get eyes on the traffic.

It comes down to this. If ATC calls out traffic to you and you pick it up on ADS-B or TCAS, but you don’t actually see the traffic through your windscreen, the correct and only response is, “Negative contact”. If you see the traffic through the windscreen, your response should be, “Traffic in sight”. Telling the controller you have ID-ed the traffic on ADS-B or on TCAS is irrelevant and unnecessary.

Then Is There Any Value in TIS-B?

The real value in the Traffic Information Service component in ADS-B is it helps you build situational awareness of traffic in your area. It may also help you spot traffic when ATC calls it out to you. TIS-B may even help you spot traffic when the controller is too busy to point it out.

Perhaps someday the FAA will develop new ATC procedures based on your ability to ID traffic on your ADS-B set. That day has not yet arrived. Until it does, the only two standard and useful responses to a traffic call out from ATC are “Traffic in sight” or “Negative contact”.

Questions? Comments? Write to me below in the comments section, or send an email directly to

{ 8 comments… read them below or add one }

Rich Smith January 26, 2017 at 11:26 am

As a controller (now retired), I was obliged to keep issuing traffic until either the aircraft reported the traffic in sight or they were no longer traffic, so, even if the pilot advised they had the traffic on TCAS, we were to keep issuing the traffic until they got it in sight or passed it. Ref: 7110.65W, 2-1-21.


JeffKanarish January 26, 2017 at 11:35 am

Thank you Rick. I’ll update the article. Good to hear from you.



George January 27, 2017 at 2:41 pm

I thought that was wrong. ATC wants to hear “traffic in sight” or ” Negative contact”. So thanks for owning up for that. Be well, Jeff


George January 27, 2017 at 2:52 pm

ADS-B and TIS and TCAS.etc only gives you advanced information on where to look for traffic. Traffic needs to be insight out the window. If not in sight, “negative contact” is the correct reply. Not “looking for it”. I hear that a lot and it is unnerving.


George January 27, 2017 at 3:00 pm

I listen to LiveATC Morristown NJ and I have never heard “negative contact” . Every one says “looking”. That is wrong.


JeffKanarish January 27, 2017 at 6:17 pm

I love that expression, “Everything popular is wrong”. Thanks for commenting.



Gc mishra March 16, 2018 at 6:29 pm

It may not so much be a case of what ATC wants to hear, but more of what makes the situation safe. Once pilot has traffic on TCAS, he knows where and when to expect to see the traffic. Avoidance, if any, would still be best coordinated on RA in IFR environment. More importantly, it’s also about wake avoidance that pilots use traffic info for. As a pilot I trust ATC will keep me clear of traffic, but quite unsure if he understands fully when I might be in wake. My suggestion would be that controller understand a lot of safety is thrown in once a pilot has TCAS or ADSB contact.


Dr .Loden Rogers June 4, 2018 at 9:05 pm

I thought that was wrong. ATC wants to hear “traffic in sight” or ” Negative contact”. So thanks for owning up for that. thanks for sharing such useful post.


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