Today I was looking at Flighware of LAX and I noticed that the colors GREEN and BLUE were used on flights, what does this colors mean? I also noticed that some flights did not have the Alt. or Speed being indicated but it had "estimate" on the flight. Does that mean the transponder is not working correctly?

Flightaware does not use the same screen a controller would see, it's their own setup as far as I know.

Green flights appear to be flights in the area but not flying to or from the selected airport. Blue are flights going to or from the airport you're looking at, LAX in this case.

I don't believe that the data blocks are similar to what ATC uses either. The estimate probably just means that Flightaware doesn't get data for that flight. It's notoriously buggy so this is not a huge surprise, I'm sure the flight's transponder is fine.

Quoting BMI727 (Reply 1): I don't believe that the data blocks are similar to what ATC uses either.

Mostly not, though I do believe that the altitude and airspeed blocks are the same.

-Mir

Quoting Mir (Reply 2):

Quoting BMI727 (Reply 1):

Our scopes are vastly different to what you see on the internet. And, they are mostly different in every country, sometimes with different systems at each centre.

Our typical data block has FlightID, Flight Level, Ground speed, vertical indicator (up/down arrow) and a vertical speed. We can usually see the squawk code too in place of the callsign with the push of a button.

On my current system I am able to select all of our mode S data for display on a datablock as well, that would be ModeS ID, IAS, current HDG, MCP Alt selected, barometric VS.

Quoting speedbird128 (Reply 3): MCP Alt selected

Can you actually see what alt is set in the MCP?

First of all, keep in mind that what you see on Flightaware is not valid radar data. The information you see is pooled from multiple sources and, for security reasons, is delayed by up to five minutes. The format mimics an ATC radar scope, but it is far from accurate.

When "estimate" is displayed, my guess would be that the flight isn't being tracked by the website yet, but based on the flight plan and whatever other data is available, is the website's best guess as to where the flight really is.

PC

When I toured the ELP tracon years and years ago, I recall it being very siimilar to how FlightAware shows the world...the part you could never replicate is the "flight strip" system US controllers use. One cool thing, though, that you only get to see in a TRACON is when a controller asks a flight to IDENT, then their radar return turns bright on the scope. The controller told me the same thing happens if they start squawking 7700...

Quoting KELPkid (Reply 6): the part you could never replicate is the "flight strip" system US controllers use

Most U.S. controllers in larger approach controls don't use flight strips, it's all on the display and flight strips are a royal pain in the butt. IIRC, Atlanta TRACON was using flight strips a couple of years back, some places haven't used them for 30 years.

Flightaware does have some very creative aircraft types flying around from time to time.

Quoting IAHFLYR (Reply 7): IIRC, Atlanta TRACON was using flight strips a couple of years back, some places haven't used them for 30 years.

from when i toured Indy Center last year they had the strips ready to go as back up and as a paper record, but the controller was really only focused on the computerized radar return. also the funny thing was that each controller could set up the general basics of the screen to their preferences (they were all a dark background with light radar returns, and optional sector boundaries.)

Quoting web500sjc (Reply 8): from when i toured Indy Cente

Center and TRACON, way different in how traffic is worked as well as paper work utilized.

Quoting Barney Captain (Reply 4): Can you actually see what alt is set in the MCP?

Hi sorry for the late response. Yes, I can see the MCP selected level. I also select current HDG and IAS on my display as it makes director work easier!

I will get a screenshot for you!

To add to what others have said, Flight Aware only shows IFR traffic and not VFR, SVFR or VFR flight following. That being said, there are some IFR aircraft that do not appear due to national security (Military, Air Force 1...etc) or because their registrations have been blocked from public tracking for one reason or another.

Quoting speedbird128 (Reply 10): Quoting Barney Captain (Reply 4):Can you actually see what alt is set in the MCP? Hi sorry for the late response. Yes, I can see the MCP selected level

Specifically the altitude selected on the aircraft MCP or do you mean the assigned altitude?

Quoting speedbird128 (Reply 10): I will get a screenshot for you!

I'm intrigued.  

Quoting tan1mill (Reply 11): To add to what others have said, Flight Aware only shows IFR traffic and not VFR, SVFR or VFR flight following.

Most of the time when receiving VFR flight following out of a towered airport I can see my flight on FlightAware.

Quoting David L (Reply 12): Specifically the altitude selected on the aircraft MCP

Definitely MCP altitude. My system has no facility for assigned level input. It is the level selected on the MCP of the aircraft transmitted to us over the Mode-S interface...

Quoting tan1mill (Reply 11): Flight Aware only shows IFR traffic and not VFR, SVFR or VFR flight following

I think for the most part this is correct. However a couple weeks ago I filed a VFR flight plan and afterwords was able to pull up my aircraft and see all the trip information. I didn't use flight following either. I was wondering why I wasn't able to see it a couple days ago when I filed nearly the same exact flight plan. Maybe it was just another flightaware glitch and that is why I was able to see it.
Blue

Quoting speedbird128 (Reply 14): Definitely MCP altitude. My system has no facility for assigned level input. It is the level selected on the MCP of the aircraft transmitted to us over the Mode-S interface...

I'm sorry to be redundant, but this is something I was completely unaware of - and seems a bit odd. If we are at FL230 and get cleared to FL340 - and select FL340 in the MCP window - are you saying you would then see our ALT as FL340 even though we haven't left, and are still level at FL230?

If that's the case, how do you determine actual altitude versus assigned altitude?

Quoting speedbird128 (Reply 14): Quoting David L (Reply 12): Specifically the altitude selected on the aircraft MCP Definitely MCP altitude. My system has no facility for assigned level input. It is the level selected on the MCP of the aircraft transmitted to us over the Mode-S interface...

I am going to have to research this. Not saying you are wrong at all. I just didn't/don't think that the Mode Control panel altitude select is part of the Mode S interface. Actual aircraft altitude yes, absolutely. I.E. the flight crew selects 25,000 ft. . You can see that? I'll have to revamp my knowledge if you can. I don't think you can just to put my 2 cents in. I'll check. I'm at home so I don't have access to the WDM but I would bet, am pretty sure, there is no input from the MCP to the Mode S. You may see the ACARS data or some such, but I don't think you would be able to see what is dialed in on the MCP. It is just not in the system. We'll see later this week. I don't go back to work until Thurs. Give me until then. I'll get back with you.

Quoting jetblueguy22 (Reply 15): Maybe it was just another flightaware glitch and that is why I was able to see it.

Quoting NWADC9 (Reply 13): Most of the time when receiving VFR flight following out of a towered airport I can see my flight on FlightAware.

I think the data is inconsistent in the FAA feed. There was a time when all VFR flight following showed on the feed, then it became inconsistent. The data format and sequence in the feed is also somewhat different for these flights (i.e. no from/to plan, just position messages), so each vendor (e.g. Flightaware) probably process them differently. Bottom line is that VFR flights are not guaranteed by the FAA in that feed AFAIK.


Jimbo

Quoting barney captain (Reply 16): I'm sorry to be redundant, but this is something I was completely unaware of - and seems a bit odd. If we are at FL230 and get cleared to FL340 - and select FL340 in the MCP window - are you saying you would then see our ALT as FL340 even though we haven't left, and are still level at FL230? If that's the case, how do you determine actual altitude versus assigned altitude?

We see both your Mode C level, and the MCP selected level. Our system does not allow for us to enter a cleared or assigned level.

I will upload a datablock I took a picture of.

Radar Data Block incl Mode S data

I really don't know what you are reading but it is not a selected altitude on the MCP. You can not see that. Period. It is not possible. The MCP does not interact with the Mode S or anything else other then the internal avionics of the aircraft. I just re-read the manuals on the 737 and it is not possible. There is no connection between the MCP and the transponder. Argue if you want but you are reading where the airplane is maybe??? You are not seeing the Mode Control Panels altitude, speed, decent/ascent rate, nothing off of the MCP. It just not get input to the transponder. Don't know what else to say. If you could see one thing you would see them all. Is he in HDG select, ALT select, If you could see one you should be able to see all others.

The FDR doesn't even record what selection is made on the MCP. Don't know what you are seeing but maybe it's something I don't know. It is not the MCP selection. Not debatable on the 737 anyway. It just does not give out that info..

Quoting 737tdi (Reply 20): I really don't know what you are reading but it is not a selected altitude on the MCP. You can not see that. Period. It is not possible. The MCP does not interact with the Mode S or anything else other then the internal avionics of the aircraft. I just re-read the manuals on the 737 and it is not possible. There is no connection between the MCP and the transponder. Argue if you want but you are reading where the airplane is maybe??? You are not seeing the Mode Control Panels altitude, speed, decent/ascent rate, nothing off of the MCP. It just not get input to the transponder. Don't know what else to say. If you could see one thing you would see them all. Is he in HDG select, ALT select, If you could see one you should be able to see all others. The FDR doesn't even record what selection is made on the MCP. Don't know what you are seeing but maybe it's something I don't know. It is not the MCP selection. Not debatable on the 737 anyway. It just does not give out that info..

You are wrong. Sorry, but I have to just say it like that. Period.

It is the MCP selected altitude, and yes, it does come from 737's too.

I suggest you do some research on Mode-S and its extended squitter transmissions.

Quoting 737tdi (Reply 20): It is not the MCP selection. Not debatable on the 737 anyway. It just does not give out that info..

It is. It is debatable. And it does. I just showed you my radar screen target.

I can watch the MCP selected altitude being dialled up or down depending on how slowly it is changed by the cockpit crew.

[Edited 2012-11-19 14:55:12]

Mr tdi, please visit the following link

http://www.eurocontrol.int/articles/mode-s-operational-overview

And you scroll down to Mode S Enhanced Surveillance, and you can read for yourself from the Eurocontrol website what information is transmitted over Mode S.

I suggest you do some research on your 737 and its abilities.. I could theoretically even get Roll Angle....  

[Edited 2012-11-19 14:59:29]

[Edited 2012-11-19 15:00:42]

Quoting speedbird128 (Reply 19): Then, in addition (on another line in our radar datablock), I will have the MCP (or Selected, hence the S370) alt, IAS, and HDG. You can see the MCP level set as F370, the IAS is 300KIAS (if I was an upper sector I could select Mach Number instead of IAS), and the HDG is 187.

If in fact what you are telling us is correct, that is certainly another crosscheck of altitude verification beside the readback of a new altitude assignment. How long have you had this ability?

In the U.S. enroute environment IIRC the sector controller is entering the assigned altitude into the datablock. Don't work enroute so not 100% sure of that but I believe that's how it happens, certainly not from the MCP.

Quoting speedbird128 (Reply 21): I can watch the MCP selected altitude being dialled up or down depending on how slowly it is changed by the cockpit crew.

So the Mode-S squitter is updating every what 1/2 second?

I'm off to research a bit on the Mode-S squitter to make sure this isn't some sort of ADS-B transmitting from an A Spec box.

I will say I give up, I wil not argue a point on the computer. The Boeing 737 MCP has no, zero, nada, nothing, input into any air traffic control system. I don't no how else to say it. It just does not. You may beleive it is true but it is just not!!!! I want an apology when you discover you are wrong. There is no input from the MCP. PERIOD.

Quoting speedbird128 (Reply 21): It is not the MCP selection. Not debatable on the 737 anyway. It just does not give out that info..

Quoting speedbird128 (Reply 21): It is. It is debatable. And it does.

Well, this is interesting.

Quoting 737tdi (Reply 23): The Boeing 737 MCP has no, zero, nada, nothing, input into any air traffic control system. I don't no how else to say it. It just does not. You may beleive it is true but it is just not!!!!

You may want to tell Boeing. *Some* 737 MCP's have no input to the transponder. But some do. It depends which specific 737 you're looking at. I'm staring at a 737-800 manual right now that says, flat out, that their ATC transponder gets data from the MCP (this particular aircraft lives in Europe).

EU (where speedbird128 works, I assume) requires Mode-S Enhanced Surveillance for larger airliners, including the 737, which includes several extra downlink parameters beyond the basic Mode-S Elementary Surveillance. They send the ADS-B data over the Mode-S extended squitter. This does involve additional connections between aircraft systems and the transponder, which are all nicely documented in the manuals.

Quoting 737tdi (Reply 23): I want an apology when you discover you are wrong.

I'm sure speedbird128 will appreciate your apology.

Tom.

Quoting 737tdi (Reply 23): I want an apology when you discover you are wrong. There is no input from the MCP. PERIOD.

Sorry, I am all out of apologies for this matter  

I know what I know. I know what I deal with in the air traffic environment every day of my life.

You're welcome to come visit our centre and I will educate you.

Quoting IAHFLYR (Reply 22): So the Mode-S squitter is updating every what 1/2 second? I'm off to research a bit on the Mode-S squitter to make sure this isn't some sort of ADS-B transmitting from an A Spec box.

At least 1/2 sec. I will try find out what the output frequency of the data is.

Quoting IAHFLYR (Reply 22): If in fact what you are telling us is correct, that is certainly another crosscheck of altitude verification beside the readback of a new altitude assignment. How long have you had this ability? In the U.S. enroute environment IIRC the sector controller is entering the assigned altitude into the datablock. Don't work enroute so not 100% sure of that but I believe that's how it happens, certainly not from the MCP.

Effectively yes. Later on when we get the ability to digitise our CFL (cleared flight level, or assigned level), it will trigger an alert for us if the cockpit crew select a level different to the CFL, or vice versa, if we make a mistake entering a level different to what we said.

In all its another safeguard to alert us to a mismatch.

I don't think the EHS is currently mandatory, but I have had the ability on my screen for more than a year now.

Quoting 737tdi (Reply 23): The Boeing 737 MCP has no, zero, nada, nothing, input into any air traffic control system

Perhaps not the 737-100 or -200... Get with the times, we have -300 thru -900's now 

OK so I did the research, and here are the published parameters as per the Eurocontrol page I linked to...

These fields are obviously depending on the aircraft equipment. However, 99% of the commercial jet traffic through my airspace is equipped for this data transmission.

Here are all the data fields we can get through Mode-S

Here are all the data fields we can get through ADS.

There is no question over this. They have the ability to see MCP selected altitude.

Funnily enough, I have heard Air Traffic Control query whether a US based airline has understood their cleared altitude based on their MCP selection. The aircraft was departing Gatwick on a SID that included two step climbs, I believe the initial altitude was 4000ft followed by steps at certain points on the departure to 5000ft and then finally 6000ft. I assume that the SOP for the particular airline was to set the final cleared altitude (6000ft) in the MCP and then fly the SID in LNAV and more importantly, VNAV. They would then leave the hard altitudes in the FMC and if it came to it the aircraft would level off in VNAV at the appropriate altitude. An approach controller then queried the flight crew after departure as on his radar screen he would be able to see the mode S data (MCP altitude of 6000ft, not the initial altitude that they would be cleared to) and not the FMC constraint of 4000ft until whatever point in the departure.

Well, I'll be...

Speedbird128 1 - Sceptics 0.  

Quoting EGGD (Reply 30):

It's our policy to set the final altitude as well in order to make sure that the aircraft climbs on schedule. VNAV will take care of the intermediate level-offs. I've done it also on descents were we're told "descend now to FL390, then cross [$WAYPOINT] at FL310" and we can anticipate being level at FL390 for a while. 390 goes in the MCP and we go down, then once we get to FL390 I'll reset it to FL310 and wait for the VNAV path to descend to meet us, then continue down from there. If ATC was watching the MCP altitude, they'd think we hadn't understood the crossing restriction.

-Mir

Quote: I've done it also on descents were we're told "descend now to FL390, then cross [$WAYPOINT] at FL310" and we can anticipate being level at FL390 for a while. 390 goes in the MCP and we go down, then once we get to FL390 I'll reset it to FL310 and wait for the VNAV path to descend to meet us, then continue down from there

Where was this?

I stand to be corrected by an ATCO but my understanding, and the way I and fellow colleagues operate is, that it would be more along the lines of "Descend now FL390, expect to cross ABCDE (waypoint) FL310 or below" I wouldn't descend below FL390 until I had explicit clearance. The information provided by ATC on the waypoint restriction is more for planning purposes rather than an instruction to descend to that level...

[Edited 2012-11-20 07:12:27]

Quoting Boeing77W (Reply 33):

What Mir said is correct and a fairly common clearance*

*Disclaimer: this applies in the USA. It's my understanding that there are some subtle differences in the way crossing restrictions and pilot's discretion clearances (crossing restrictions being a type of pilot's discretion clearance) communicated in USA and in ICAO phrasology.

Most interesting for sure.

I'd love to know why the FAA ATC facilities that are using ADS-B as one of their sensors right now don't have the ability in the software to put this data into the display? Aircraft that are equipped with the "A Spec" box are not even showing they are equipped with any type of ADS-B let alone providing the controller with any data fro the MCP or aircraft track, speed, etc. In fact, I've only seen two aircraft that we using the "B Spec" box which is what the software is capable of using as the sole source for ADS-B/ADS-B separation standards they tell us some office some place is working on......yeah right!!!

Great job speedbird, thanks and welcome to my RU's.

Quoting EGGD (Reply 30):

I personally expect to see the MCP set to 6000 and not the constraints as the fms is programmed with "cross at" limitations...

Quoting Mir (Reply 32):

I personally would expect to see both methods... Some would put a soft constraint in the MCDU or FMC... We managed before mode-s EHS so its nice to see whats going on.

If i might add, the best benefit of having MCP altitude is on my system's STCA warning. It shows who is climbing/descending to what level as soon as the alert is triggered. Sure no guarantees of a level off, but if an STCA is triggered and both MCP altitudes are the same it will be evident immediately its not a benign/erratic stca warning...

Quoting speedbird128 (Reply 36): I personally expect to see the MCP set to 6000 and not the constraints as the fms is programmed with "cross at" limitations...

That is fair enough. I'm used to our SOP which states that we set the MCP to the altitude constraints and then reset it as we pass each one, we usually also delete the hard altitudes when entering the route in the pre-flight stage. As always, many ways to skin a cat I suppose.

Wow, once we stepped away from the Flightaware part this thread became very informing. And where's that apology? LOL jk, too funny.

Quoting EGGD (Reply 37): That is fair enough. I'm used to our SOP which states that we set the MCP to the altitude constraints and then reset it as we pass each one, we usually also delete the hard altitudes when entering the route in the pre-flight stage. As always, many ways to skin a cat I suppose.

Indeed - many ways to deal with this scenario... i am fully prepared to see both methods and if I am in doubt then i will just ask to make sure...

Quoting My16sidedoffice (Reply 38): And where's that apology? LOL jk, too funny.

haha yes was hilarious and given his/her conspicuous absence it's even funnier now...

Quoting IAHFLYR (Reply 22): So the Mode-S squitter is updating every what 1/2 second? I'm off to research a bit on the Mode-S squitter to make sure this isn't some sort of ADS-B transmitting from an A Spec box.

I have found out that the transmission interval is 0.5s. One sector here have just had WAM installed and the update frequency is wicked for director work... And WAM is Mode A/C/S capable also, so doesn't affect aircraft equipment...

As for the data origins - its all transmitted on the 1090MHz frequency (interrogation by mode A/C/S SSR is 1030MHz), so yes, it seems to share the ADSB data stream. So while It seems Mode S and ADSB are very closely linked, they are not the same though.

I would like to see Mode-S data on our scopes IAHFLYR! Wouldve saved me from a terrain deal...something IAH doesnt know much about  

Speedbird,
Thats some pretty cool stuff. Maybe in 20 years we'll have it as well!

atct

Quoting atct (Reply 40): ...something IAH doesnt know much about

What don't they know about, terrain or deals?   I think they know plenty of both, just the terrelian is calls antennas/buildings.

Quoting speedbird128 (Reply 39): As for the data origins - its all transmitted on the 1090MHz frequency (interrogation by mode A/C/S SSR is 1030MHz), so yes, it seems to share the ADSB data stream. So while It seems Mode S and ADSB are very closely linked, they are not the same though.

Excellent information. I sent an email to a tech dude who works on the software development in Atlantic City, but he is probably off this week due to the holiday. Hope for some good feedback next week from him on this topic.

Quoting 737tdi (Reply 23):

has been very quiet, not surprised in the slightest...

Quoting IAHFLYR (Reply 41): Hope for some good feedback next week from him on this topic.

Any info from your side?

Quoting Speedbird128 (Reply 42): Any info from your side?

Not enough yet to sort out and make sense if you know what I mean. I'll send another message and we shall see what that brings. My guess is the STARS equipment doesn't use the data thus it's not displayed on the control position, and why not I hope to find out.

Quoting Speedbird128 (Reply 42): Any info from your side?

Got some info on why you're seeing this stuff and U.S. controllers are not yet, very interesting to say the least. Maybe in NextGen? Yeah right!!!

Anyway here is some of the reply validating what you posted:

"Eurocontrol Mode S can operate in two modes - Elementary Surveillance (ELS) and Enhanced Surveillance (EHS). EHS can transmit additional data, like Selected Altitude, Roll Angle, Track Angle Rate, True Track Angle, Ground Speed, Magnetic Heading, Indicated Airspeed / Mach No and Vertical Rate. Apparently, aircraft with a maximum takeoff weight greater than 12,566 lbs or a maximum cruise true airspeed greater than 250 knots must be equipped with Mode S EHS to operate in the United Kingdom, Germany and France.

It looks like their aircraft have upgraded their avionics to process this additional information and their ATC systems have been modified to accept and process this Mode S EHS data right from the radar. The U.S. has not adopted the ELS or EHS extensions to Mode S, so even though their aircraft may have the ability to deliver this information to the radars, we don't process the additional data and send it along to ATC."

ADS-B target reports contain Selected Altitude but it's not currently processed. So even if Mode S EHS is never adapted here, it could potentially be processed from and ADS-B report if it was decided to open up this field for input and processing.

We are still waiting for that apology, and I'm not kidding!!!!  

Quoting IAHFLYR (Reply 44): still waiting

haha funny... I don't think he will be back in this thread.

Quoting IAHFLYR (Reply 44): here is some of the reply

I think its a crying shame that a new system (a la NextGen) is being deployed without this functionality (and our system is not exactly new either!)... Your man is correct in that it is Mode S EHS we have

The only time it might cause us some issues from an undesirable effect, is when the aircraft is on the approach and sets the MCP alt to the go-around limits... where I am its level 60... so next year when our system is updated with digital flight progress strips - we're currently still on paper, (go ahead and laugh now) it might trigger an alert to an assigned altitude/selected altitude discrepancy...

That aside, its BENEFITS all the way... I cannot see why when this kind of information is available it is not going to be displayed...

Quoting Speedbird128 (Reply 45): I think its a crying shame that a new system (a la NextGen) is being deployed without this functionality (and our system is not exactly new either!)...

My NextGen comment was directed toward what they're actually getting into some places next year call TAMR. I don't believe it will have the EHS capability on roll-out, so who knows. Something about the the integrity of the data coming from the avionics on the aircraft which sounds suspect in its own right.

Do you get EHS data from U.S. flag carriers and large corporate operators?

Quoting IAHFLYR (Reply 46): Do you get EHS data from U.S. flag carriers

Yes.

Quoting IAHFLYR (Reply 46): and large corporate operators?

I'll pay more attention to which bizjets are EHS capable... I am sure I had a 7X this morning with EHS.

Quoting IAHFLYR (Reply 46): Something about the the integrity of the data coming from the avionics on the aircraft which sounds suspect in its own right.

Yes... I think that is one perceived drawback of the ADS-B transmissions... in reality I really have no idea how easy it would be to mess with the data streams... I know I have a pole on my roof of my house and I can receive the ADS-B data... Hence the sites like FlightRadar24 exist... it just taps into the free-to-receive datastreams on the ADS-B output...

Quoting IAHFLYR (Reply 46): and large corporate operators

I would have to say yes for over 50%... I had the following non-scheduled in the last hour...

C560
C56X
DH8D
C525
AT45
BE20
P180
C182

(Granted the turboprops were not corporate, but it gives an indication of what types are having EHS these days)

These all had EHS (HDG, MCP ALT, and IAS on my screen anyway).

Then one C525 with IAS and HDG, but no MCP ALT.

You must understand that he has no time to apologize, he is busy checking that the world is flat and the sun is spinning around it...