Strange Squawk Code

How does one track a single hit?

99% of radars are fed to a fusion engine that presents a single air picture. A track is not tracked by code, but by a unique track ID. Should a track squawk a certain code (even for one hit), the track is identified. It even tracks primary.
 
99% of radars are fed to a fusion engine that presents a single air picture. A track is not tracked by code, but by a unique track ID. Should a track squawk a certain code (even for one hit), the track is identified. It even tracks primary.

By definition, a single hit cannot be tracked. This single hit is generated by a pilot dialing through one of the warning codes. The previous code and the code being dialed in would also be shown, they tell the tale.
 
There's nothing to deal with in this case. The alarm is only generated while the radar sees the code.
So if I squawk 7500 and then my transponder is shot by the hijackers after just one hit, the alarm goes out and you guys go back to sleep? I don't think so. Nor do I think there's anything the pilot can say to prevent a full-scale response once a 7500 code has been received, even for just one hit. As noted above, it's my understanding that a 7500 code triggers alarms in more places than just the scope of the controller working that track.
 
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By definition, a single hit cannot be tracked. This single hit is generated by a pilot dialing through one of the warning codes. The previous code and the code being dialed in would also be shown, they tell the tale.

Last post because I'm not going to get into it.

I'm not saying the tale isn't known but I am saying that if an aircraft is in radar coverage and squawks 7700, 7600 or 7500, and the transponder replies to a interrogation with that code for even one hit, it will be known and it will be capable of being tracked (while it stays in radar coverage).

It's post-9/11 and a brave new world. If you think that's cool check out passive radar.
 
I'm not saying the tale isn't known but I am saying that if an aircraft is in radar coverage and squawks 7700, 7600 or 7500, and the transponder replies to a interrogation with that code for even one hit, it will be known and it will be capable of being tracked (while it stays in radar coverage).

In other words, you're saying it's a non-event, which is what I said.
 
I give up trying to get anything useful from Steven. All the information I have says even one hit on a 7500 code is going to get noticed by lots of folks and get tracked to destination where you will be met. Anyone who thinks otherwise is free to try it at their own risk.
 
6-3-4
c. Air traffic controllers will acknowledge and confirm receipt of transponder Code 7500 by asking the pilot to verify it. If the aircraft is not being subjected to unlawful interference, the pilot should respond to the query by broadcasting in the clear that the aircraft is not being subjected to unlawful interference. Upon receipt of this information, the controller will request the pilot to verify the code selection depicted in the code selector windows in the transponder control panel and change the code to the appropriate setting. If the pilot replies in the affirmative or does not reply, the controller will not ask further questions but will flight follow, respond to pilot requests and notify appropriate authorities.

If you get one 7500 hit, like Steven said, it's not even worth asking "verify squawking 7500." I never saw a accidental 7500 when I did ATC but somehow I don't think Center would be bugging me on the landline about a brief 7500 code. Maybe things have changed after 9/11.
 
I have to admit I'd really like to be right in regards to my FO...but I'm not too proud to admit I'm wrong if that's the case. I'd just like to know if its worth mentioning going forward. There's two people on this thread with my respect giving conflicting answers...
 
I give up trying to get anything useful from Steven. All the information I have says even one hit on a 7500 code is going to get noticed by lots of folks and get tracked to destination where you will be met. Anyone who thinks otherwise is free to try it at their own risk.

It appears you're relying on poor sources for your information.
 
I give up trying to get anything useful from Steven. All the information I have says even one hit on a 7500 code is going to get noticed by lots of folks and get tracked to destination where you will be met. Anyone who thinks otherwise is free to try it at their own risk.

This does not jive with my experience. But don't let that stop you from believing in "all the information (you) have." :cheerswine:
 
Just called ZJX ARTCC Sup to pretty much confirm what I already knew. He said they get accidental 7500,7600,7700 all the time. His description on how they handle it was basically like the AIM outlines. While a 7500 code sends off alarms and phone calls from different agencies, if it's accidental it is a "non event." He also said the odds of a cycle through being picked up would be very slim since their refresh rate is like every 12 secs.

I know there are cases of law enforcement and military intercepts on accidental 7500s but I think they were situations were the pilots didn't reply properly or didn't reply at all.
 
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I give up trying to get anything useful from Steven. All the information I have says even one hit on a 7500 code is going to get noticed by lots of folks and get tracked to destination where you will be met.


It appears you're relying on poor sources for your information.


Google??? :rolleyes:
 
How about switching to standby, then change the code?
 
. He said they get accidental 7500,7600,7700 all the time....


...He also said the odds of a cycle through being picked up would be very slim since their refresh rate is like every 12 secs.

Anyone else see the disconnect here? If the odds are all that slim, why does it happen "all the time"?

And in the spirit of full disclosure, I must admit I've never been in the habit of switching to standby before entering a new code, I was merely pointing out that such is the recommended practice. I also don't recall ever seeing another pilot do it.
 
Anyone else see the disconnect here? If the odds are all that slim, why does it happen "all the time"?

And in the spirit of full disclosure, I must admit I've never been in the habit of switching to standby before entering a new code, I was merely pointing out that such is the recommended practice. I also don't recall ever seeing another pilot do it.

I don't. But I take care not to cycle through those codes. All the transponders I use have separate knobs for each digit, so it isn't that much of an issue.
 
I don't. But I take care not to cycle through those codes. All the transponders I use have separate knobs for each digit, so it isn't that much of an issue.
JOOC, do the alarms at ATC only go off if you hit a 7700, 7600, or 7500 code or do they trigger on anything starting with 75-77?
 
Anyone else see the disconnect here? If the odds are all that slim, why does it happen "all the time"?

And in the spirit of full disclosure, I must admit I've never been in the habit of switching to standby before entering a new code, I was merely pointing out that such is the recommended practice. I also don't recall ever seeing another pilot do it.

No disconnect. Two different things you're referring to. The center controller said it's "slim" for an emergency code to be picked up by their radar while cycling through to your assigned code. Since he has a 12 sec update rate, I'd have to agree. So then how do they get these accidental emergency squawks? Guys who flat out selected the wrong code, Playing with the transponder on the ground and selecting the wrong code (seen that), malfunctioning transponder or interrogator.

While I never saw any 7500 codes, in 8 yrs of doing ATC, I did see several accidental 7600 and 7700 codes. Had a guy once on FF start squawking emergency about 30 miles from his destination. He tried everything to reset but to no avail. He apologized profusely but it was no big deal to me. Also seen 7700 on the ground with guys doing maintenance. Stuck ELTs a few times well. I have seen 7700 for a split second before. Whether or not it was a cycle through or a glitch, I didn't know and didn't care. Since my radar sweep was at every 4.5 secs it just might momentarily pick up someone changing codes. As Steven said, if it happens for a split second and you might not even know who squawked it anyway. I wouldn't call my experience with emergency codes as happening "all the time," but I didn't work at a center that's open 24 hrs a day and has a huge airspace either.

Some transponders have a single emergency select switch. In the Black Hawk we had that switch and I know on at least one occasion I had a student select it by accident. Nothing happened. There's a LR-60 NASA report online where their company had the emergency codes as preselects. One push of the button and you've selected something you didn't want. While they got in trouble for a 7500 code, it was because they acknowledged the 7500 verification.

If you read the 7610.4 and the AIM. They are quite clear on how to handle an accidental 7500 transmission. Authorities are notified for either a yes reply or no reply at all. The JAX Center controller I talked to yesterday said they handle it just like that. I even texted two current approach controllers yesterday and asked how they handle it and they said basically the same thing. My friend who works at ATL app:
"If it was by accident, then nothing happens. No reports are made. If you were not talking to ATC, we would notify the DEN and you would be tracked / intercepted."

So if you all want to worry about something that's treated as a "non event" then go ahead. Why would the controller ask the question "verify squawking 7500" if security measures are automatically implemented? They ask it so they don't send people and aircraft out needlessly to handle something that's obviously a mistake. I'm sure there are more intercepts for mistaken ADIZ penetrations and lost commo route deviations than 7500 codes. I've seen both of those first hand.
 
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No disconnect. Two different things you're referring to. The center controller said it's "slim" for an emergency code to be picked up by their radar while cycling through to your assigned code. Since he has a 12 sec update rate, I'd have to agree. So then how do they get these accidental emergency squawks? Guys who flat out selected the wrong code, Playing with the transponder on the ground and selecting the wrong code (seen that), malfunctioning transponder or interrogator.

While I never saw any 7500 codes, in 8 yrs of doing ATC, I did see several accidental 7600 and 7700 codes. Had a guy once on FF start squawking emergency about 30 miles from his destination. He tried everything to reset but to no avail. He apologized profusely but it was no big deal to me. Also seen 7700 on the ground with guys doing maintenance. Stuck ELTs a few times well. I have seen 7700 for a split second before. Whether or not it was a cycle through or a glitch, I didn't know and didn't care. Since my radar sweep was at every 4.5 secs it just might momentarily pick up someone changing codes. As Steven said, if it happens for a split second and you might not even know who squawked it anyway. I wouldn't call my experience with emergency codes as happening "all the time," but I didn't work at a center that's open 24 hrs a day and has a huge airspace either.

Some transponders have a single emergency select switch. In the Black Hawk we had that switch and I know on at least one occasion I had a student select it by accident. Nothing happened. There's a LR-60 NASA report online where their company had the emergency codes as preselects. One push of the button and you've selected something you didn't want. While they got in trouble for a 7500 code, it was because they acknowledged the 7500 verification.

If you read the 7610.4 and the AIM. They are quite clear on how to handle an accidental 7500 transmission. Authorities are notified for either a yes reply or no reply at all. The JAX Center controller I talked to yesterday said they handle it just like that. I even texted two current approach controllers yesterday and asked how they handle it and they said basically the same thing. My friend who works at ATL app:
"If it was by accident, then nothing happens. No reports are made. If you were not talking to ATC, we would notify the DEN and you would be tracked / intercepted."

So if you all want to worry about something that's treated as a "non event" then go ahead. Why would the controller ask the question "verify squawking 7500" if security measures are automatically implemented? They ask it so they don't send people and aircraft out needlessly to handle something that's obviously a mistake. I'm sure there are more intercepts for mistaken ADIZ penetrations and lost commo route deviations than 7500 codes. I've seen both of those first hand.

I guess I'm changing my tune on this and agreeing it might be a non-event.

I bolded the bit above just to remind that just because a particular controllers radar only sweeps once every 12 (or 4.5) seconds there are many radars that constantly ping the plane. Looking at the 'reply' light on any transponder in most parts of the country at altitude you see it flashing so fast it almost looks like a steady light. My understanding was all those radars feed into a central system so any 7500 reply to any interrogation (ground based) would trip the alarm and automatically tie that code / alarm to my contact.
 
In the AOPA "Ask a controller" videos they say pretty clearly that they don't want people putting the transponder into standby while changing codes. Is it really that hard to do it carefully?
 
In the AOPA "Ask a controller" videos they say pretty clearly that they don't want people putting the transponder into standby while changing codes. Is it really that hard to do it carefully?

Oy Vey...why would they care if a transponder goes into standby during the switch?



People...rules need a reason. If there is NO reason then the rule is stupid. Every time you hear a new 'rule' please ask yourself the 'reason'. If there is none then challenge it. We're supposed to be a 'free nation' after all...
 
Oy Vey...why would they care if a transponder goes into standby during the switch?



People...rules need a reason. If there is NO reason then the rule is stupid. Every time you hear a new 'rule' please ask yourself the 'reason'. If there is none then challenge it. We're supposed to be a 'free nation' after all...

Very simple really:

http://aopalive.aopa.org/?watch=lvMWc2MzptkBQ6Wj8MKJ474FJzirPjKU

Just because you don't know the reason, it doesn't mean there isn't one. Also, I wouldn't call it a "rule". The better we know how each other works, the better flying is, both in terms of safety and in terms of friendliness.
 
Sheesh. I was taught that before you change your code, you go to STANDBY, and that's why it's there. Why the hell else would it be there? Otherwise you would have ON and TRANSMIT.

Garmin cures all of these headaches.
 
Sheesh. I was taught that before you change your code, you go to STANDBY, and that's why it's there. Why the hell else would it be there?

So that you could respond to the ATC instruction "squawk STANDBY"?

Otherwise you would have ON and TRANSMIT.

No OFF? No ALTITUDE? How would ON differ from TRANSMIT?
 
Sheesh. I was taught that before you change your code, you go to STANDBY, and that's why it's there. Why the hell else would it be there? Otherwise you would have ON and TRANSMIT.

Garmin cures all of these headaches.

Ground ops where they DON'T want you squawking. You weren't taught wrong, you were just taught...well...based on bad information.
 
Ground ops where they DON'T want you squawking. You weren't taught wrong, you were just taught...well...based on bad information.

Fair enough. But I would prefer a complaint from Ground compared to a complaint from any ATC entity that I inadvertently squawked 7700, 7600, or 7500.

Again, I tip my hat to Garmin! :)
 
Ground is an ATC entity.


Whatever. The point is that my method prevents me from inadvertently squawking the three codes in question. I'd prefer ground to say, "Oh, we lost you there for 1.5 seconds," to Tower assuming I've been hijacked.

But AGAIN, for the THIRD time: Garmin has solved this problem.
 
How about just being cognizant when spinning the knobs?
 
But AGAIN, for the THIRD time: Garmin has solved this problem.

yhst-10237233231589_2255_9789584


How?
 
Whatever. The point is that my method prevents me from inadvertently squawking the three codes in question. I'd prefer ground to say, "Oh, we lost you there for 1.5 seconds," to Tower assuming I've been hijacked.

But AGAIN, for the THIRD time: Garmin has solved this problem.

What problem?
 
How about just being cognizant when spinning the knobs?

No, I don't think that's right. That'd mean you'd also have to be familiar with other things like how to fly your airplane, what those knobs and dials mean, etc. :wink2:
 
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