AirNav Systems Forum
AirNav RadarBox and RadarBox24.com => AirNav RadarBox and RadarBox24.com Discussion => Topic started by: phil zech on November 10, 2008, 07:23:13 PM
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Evening All,
I live in Sale about 5 miles from MAN.
In 'my flights' for the past couple of hours a Mode S code '000000' keeps being listed.
All it shows is 'Levelled' , 000000 only, it then gets 'timed out' but then
reapears, any suggestions of what could be causing this.
Is there anyone else in the North West that have this in their flights.
Regards
Phil
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Hi Phil
Yes, I'm in Chorley, north of Manchester, and I see this quite often - myLog says I first got it in August, and the last date was 16th October. No other details at all though.
No idea what's going on - it could even be from more than one source?
Rod
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Hi Rod,
Glad its not only me then.
Must be a North West thing.
It disappeared after I turned RB off and back on again.
One other point, great job with the outlines and logos.
Cheers
Phil
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Thanks, Phil.
We could start a rumour that it's a secret stealth bomber project from Warton ;-)
Rod
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Possibly one of the "mysterious one-second transmissions" that has been discussed for months over on the "other" forum - see http://www.kinetic-avionics.co.uk/forums/viewtopic.php?t=5691
Theories range from ACMI pods, CAA test transmissions, Klingons, Tardis, etc...........
I've been getting these strange transmissions for months.
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I can added another one:
Last week we drove in a Saab 93 and used the Radarbox on a EEE901.
As long as the auto was turned one 000000 showed up in the active list. After shutting down the car 000000 did disappear.
Harry
Possibly one of the "mysterious one-second transmissions" that has been discussed for months over on the "other" forum - see http://www.kinetic-avionics.co.uk/forums/viewtopic.php?t=5691
Theories range from ACMI pods, CAA test transmissions, Klingons, Tardis, etc...........
I've been getting these strange transmissions for months.
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I've been seeing hex code 000000 a lot today. The squawk codes used are interesting:
0007 - Strange one - may 007!!
3352 - London Military
0465 - Waddington Special Tasks
2006 - Orcam Shannon Centre
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Been getting the 000000 over here on the other side of the country so maybe not just a Lancashire/Cheshire thing
Any way does anything fly serviceable out of Warton? ;-)
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Hi all
000000 is on the box here in Northern Ireland also along with 00000F??
000000 showing level sqwk 2004 Transit (ORCAM) Shannon while in the cruise 00000F has nothing shown at all??
John
edit just noted 00000F flash a height at 29450.
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00000 is now squawking 2462 (NATO CAOC 9 Exercises). I suspect it's part of the CQWI Exercises.
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Are we saying that there is more than one 000000?
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Possibly. I'm seeing regular squawkcode changes, so maybe more than one aircraft. Currently 000000 is squawking 0007 again.
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Just a thought is is the FR Aviation Falcons, who are part of the CQWI exercise, when they are active? I note if they appear in their own right I don't see the 000000!!
John
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I'm watching the Falcons and the various Sentinel and Sentry aircraft to look for any correlation between them and these 000000 signals. Even Nimrods. No luck so far. It's VERY active at the moment on the CQWI exercise.
It's the strange range of squawk codes that puzzles me. Currently 000000 is squawking 0060, which according to my list is reserved for the police force airborne units.
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Hi.
Mode-S 000000 is now near Faro, Portugal squawking 0556.
Well using plenty of squawks and no altitude.
Squawks used:
7156
7106
0524
0405
4414
5506
4405
4525
1040
no squawk and FL380
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I have picked up this 000000 code twice in the last week here in southend.
I think it may be a helicopter using callsign Dubai 139 .
Ian
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More squawk codes for 000000:
2554
0602
1507
4615
3245
4127
0250
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I get this often and I'm in the United States. I also get 000001 and I think squawk codes change on that one too.
At times it seemed liked it coincided with a US Customs helo that wasn't using it's assigned mode-s code. The altitude displayed tended to match the helo's.
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There is the possibility that the latest software upgrade and allowing ANRB to be to the same level of reception and individual flights as SBS1 that these "ghost" codes will become a feature of the ANRB as they have been on the other device. I get these codes on a daily basis but they normally start and fin ish at the same time, although sometimes the finish time is earlier than the start time :-). They are possibly internally generated by the reciever, just like the Birdies that can be received on Airband radios ?
Mike
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There is the possibility that the latest software upgrade and allowing ANRB to be to the same level of reception and individual flights as SBS1 that these "ghost" codes will become a feature of the ANRB as they have been on the other device. I get these codes on a daily basis but they normally start and fin ish at the same time, although sometimes the finish time is earlier than the start time :-). They are possibly internally generated by the reciever, just like the Birdies that can be received on Airband radios ?
Everything we see on our screens is derived from a 56-bit or 112-bit packet radio transmission from the aircraft. Like any transmission, it's subject to distortion and interference, and since 24 of those 56/112 bits represent the aircraft's Mode S address, there's a reasonable probability that invalid addresses will be decoded from time to time.
Presumably both RadarBox and SBS have ways of trying to detect and filter out these invalid codes (bearing in mind that it's unlikely that the same corrupted address will be picked up more than once) but it seems likely that a few will slip through the net, and those are presumably the ghost codes that we see on our screens.
I don't think there is any solution for this.
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Is there not parity checking on the messages?
1. Short Squitter (56 bits):
8 bit control
24 bit aircraft address
24 bit parity
2. Extended Squitter (112 bits):
8 bit control
24 bit aircraft address
56 bit ADS message
24 bit parity
Shouldn't both SBS-1 and Radarbox check parity to avoid these types of error?
Parity check (PI field): This 24 bit field is an error detection code to help a receiver determine errors in the received message - from http://elearning.eurocontrol.int/ATMTraining/PreCourse/SUR/ADS/Taste%20the%20Course/32501.10.32657.85.28722/Default.html
The 24 bit PI field is generated by a polynomial division of the Mode S message by a fixed 24 bit polynomial. The PI field is used for detecting bit errors and may also be used for correcting bit errors in the message.
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The PI field is defined as Parity/Interrogation Identifier, and appears in the DF11 (All-Call Reply) and DF17 (Extended Squitter).
It consists of the parity bits overlaid with the interrogating radar's identity code. RadarBox/SBS has no way of knowing the latter and it follows that the PI field can't therefore be used for error detection in DF11s and DF17s.
See ICAO Annex 10, Volume IV, para 3.1.2.3.2.1.4.
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Thanks for that explanation Dave. I've struggled for a while to understand why the parity field in both the short and extended squitters can't be used to detect these types of error. As you say, since Radarbox doesn't know the radar's identity code, parity checking is not possible.
If its not even present in DF20 and DF21 messages, that would explain why we're seeing incorrect Flight IDs on some non-ADS/B aircraft now, normally explained by just a one bit error in the ModeS code.
In fact, I'm suprised we don't see more erroneous data!!
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If its not even present in DF20 and DF21 messages, that would explain why we're seeing incorrect Flight IDs on some non-ADS/B aircraft now, normally explained by just a one bit error in the ModeS code.
You'll get used to it :-)
And don't forget that bit errors in the DF4/20 and DF5/21 can also produce altitude and squawk errors, respectively !
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Indeed thats why in those rare occasions you see helis or none pressured aircraft at concorde levels.
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Post in correct thread
Have hex 000001 flight id of "x hop g" showing at 16000 ft sqk of 1104
Graham
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Indeed thats why in those rare occasions you see helis or none pressured aircraft at Concorde levels.
I wondered why in the James May "Edge of Space" programme recently, so much fuss was being made about the total dependence on Astronaut type suits, when Concorde had been flying at 60,000 feet and higher, carrying passengers without these fancy suits. Although I never had the pleasure/privilege of flying in Concorde, it was regularly commented on, that the thin layer of atmosphere James was taken up in the TR1 (not really a U2!) was clearly visible to fare-paying passengers
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You are assuming that the U2/TR1 only goes up to 70,000 ft as shown on TV.
On the Jonathan Ross show on Friday, James May happened to mention that it was quite OK to say that he flew at 70,000 ft, but that if he said that he'd flown any higher it would be classified information.
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You are assuming that the U2/TR1 only goes up to 70,000 ft as shown on TV.
Hi Allocator, that's a negative, 86,000' U2/TR1, and 90,000' for SR71!, and Concorde flown to 67,000', although 60,000' was her usual cruising height, if I remember correctly........................
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From the info I have those figures are right.
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Hi Malc, and the Lightning a climb rate of 50,000+ feet per minute, with a ceiling of some 87,500 (unofficially), over 90,000 there's not enough Oxygen in the air for combustion, without an on-board source! One of the best display routines ever that turn from the horizontal to vertical, light them up and spiral upwards until out of sight, although you could still hear it.
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Jon
Now you are talking about a proper aircraft or was it rocket? :-)
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Great memories of the Lightning displaying at RAF Gaydon many years ago when my Dad took me to the airshow.
Barrelling down the runway and then standing on its tail heading skyward like a Saturn V
Sadly now all three gone...:-(
Kind regards,
-=Glyn=-
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Great days GlynH..happy memories
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Sadly now all three gone...:-(
Have the South African Air Force retired their's now, I know they were still flying them until a couple of years or so ago?
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Have the South African Air Force retired their's now, I know they were still flying them until a couple of years or so ago?
Aren't the South African-based Lightnings privately owned?
AFAIK, the SAAF has never operated the type.
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Privately owned and still going - you can even get a ride in one if you paid the money I believe.
A friend of mine was also the Project Manager who were restoring a Lightning to flight in the US because they figured it would be easier to get a Permit to Fly than it would be over here.
Haven't heard much about this for quite a while now.
ISTR mentioning this in an earlier post around here somewhere or was I dreaming? ;^)
Here is some more info;
http://www.lightning422supporters.co.uk/
http://www.warbirdalley.com/ltning.htm
Kind regards,
-=Glyn=-
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A bit more grist for this mill - 000000 with a callsign, it's changing squawk very often - in the last five minutes it's been squawking 2461,3365, 6101, 0136 as well as 6657. Mostly no altitude is showing, but the screenshot shows 17300ft.
Rod