How accurate are arrival and departure times ?


#1

How accurate are arrival and departure times for private corporate aircraft? does flying into a FBO verses a major airport make a difference in the accuracy of the flight data for arrivals and departures?


#2

The arrival and departure times in FlightAware are the wheels-down and wheels-up time. This applies to all aircraft, not just corporate.

Not sure what you mean by “flying into a FBO verses a major airport.” Do you mean flying into an airport that handles only general aviation aircraft as opposed to those that also have airline service?


#3

Until you get a response from someone in the know here at Flight Aware, I would say arrival and departures are accurate within 5-15 minutes. There would be a couple of exceptions.
1). If the a/c’s track is dropped by the center when they freq. them to approach control and they are in the terminal environment it will show the end of their flight. The aircraft is still inbound talking to approach control.
2). Their track might get dropped if they are 10 miles from the field if the center is the acting approach controller and the a/c cancels ifr and proceeds vfr. The aircraft hasn’t landed quite yet the system will show the end of it’s flight 10 miles from the field.
3). Departures might come off vfr from a smaller airport not yet in the system until their are 10 miles from the field. It will show them beginning their flight even though they had departed minutes ago.

Landing at a smaller airport vs a major doesn’t matter with the exceptions mentioned above.

You can try linking I think it’s www,liveatc.net listen to the tower at a certain airport issue taxiing instructions to an a/c which lands and then watch it on “live tracking” here on Flight Aware.

Enjoy!
Clay


#4

Sounds like you may be confusing the arrival/depature times with the delay times.

The handy-dandy Questions/Answers link available at the top of every page here in FlightAware says there is a delay of abou6 6 minutes.

The arrival/departure times are the actual times the aircraft lands or takes flights, not the time it arrives/leaves the FBO, terminal, or other place on the field. These are hard time unless there is a computer error.


#5

damiross wrote:
“The arrival/departure times are the actual times the aircraft lands or takes flights”

So how does that work? If someone took off vfr or terminated the ifr prior to landing, how does the system know what time the a/c departed or arrived?

I just read the part about the 6 minutes, thanks. I just took a wag on the 5-15 minutes part.

Clay


#6

VFR flights aren’t tracked.

The time the IFR was terminated would be considered a landing although it actually isn’t. Ditto for departures - I’ve seen many cases where the flight “departed” yet it was in the air already.


#7

The data is delayed 5-6 minutes, so you won’t see an arrivals until 5-6 minutes after it occurs. The accuracy of the arrival time varies; it’s generally better at a major airport (often within a minute) than out in the boonies (can be ~15 minutes off). You can check the altitude in the tracklog to get an idea of how reasonable the arrival time is.


#8

Why is this Mark? Is it because of the way the IFR is cancelled via FSS and the time it takes FSS to contact ATC when the pilot cancels on the ground without any ATC services to go through?

I would think that airborne cancellations would be a slight descrepancy as compared to major airports especially if the pilot reports airport in sight and cancels.

Allen


#9

You are omitting one thing. Don’t forget about approach controllers showing arrived which stops tracking. The IFR was not terminated, and is not terminated until tower cancels it.

Do you have any flight examples on this? I have not seen this myself.

Anytime I have seen tracking (in the air as you describe above), the status shows enroute. Once ATC picks up my IFR, I am in the system and tracking picks up accordingly once my wheels leave terra firma.

Allen


#10

You’re right. I was thinking that once it was canceled then it was VFR from that point on.

Here’s an example: flightaware.com/live/flight/N44H … 180020/L67

The tracking begins with a departure from LKV18002, which I interpret 20 miles from the VOR on the 180 radial.

Here’s another one: flightaware.com/live/flight/CTA5 … /KFMG/KEKO
The KFMG I’m taking to mean the FMG (Mustang) VOR which is near Reno.

I can’t find too many other examples but, if I recall correctly, most of the ones I have seen were in the west.


#11

Ok, correct on the above.

What has happened, is that this is a typical air filed IFR flight plan or “pop up” flightaware.com/about/faq.rvt#popupifr Pilot may have filed through FSS, or ATC if ATC had the time for the request.

I’d suspect, it shows departed even though they are airborne until everything coordinates and tracking is established (maybe that lag time factored in).

The other flight CTA501 shows arrived naturally so I can’t see the filed plan, but if it displayed like N44HT while in the air, then it probably is the same thing, it was a pop up IFR.

Allen


#12

Looking at the history of the flight, it is usually an RNO/EKO roundtrip. Perhaps it’s taking off VFR from RNO and then decides to go IFR when it hits FMG VOR?


#13

I can’t explain that one. We’ve seen situations where there are two airline flights into a major airport within minutes of each other and one ends with a cancellation and the other ends with an arrival at about the same point.

NAS-MD-311 may contain the explanation, but it’s pretty heavy reading.


#14

I would imagine it has to do with when the radar facility picks you up on radar and when they loose you, not wheels up or the “system” waiting for you to cancel ifr. I would imagine you are correct to assume this happens more in the hilly terain out west vs the flatlands of america where radar coverage is more limited. The track was “probably” all done ifr, but radar coverage only occured where there was tracking.

On the nevada example, this is not to say he wasn’t vfr on Departure or Approach, but explains to me the lack of track on departure and arrival. Otherwise, why would the guy file ifr just for their enroute phase?

Interesting…


#15

Radar coverage doesn’t affect flight aware tracking. See discussions.flightaware.com/view … hlight=mcb

The following is with the stipulation I haven’t had a chance to gander at the airspace around the airports in question, but in a general sense…

There could be many reasons, one being VFR in the beginning of a flight, the airspace restrictions isn’t as bad, such as dodging MOAs. VFR traffic can go through MOA’s, where as IFR cannot IF the MOA is “hot”. If it’s cold, IFR can go through MOA’s.

Looking at the altitude, on Damiross’s flight, he maintained VFR altitudes which makes me think he wanted “VFR on top” which is much more flexible then a standard IFR flight. Plenty of discussions in the past about VFR on top as well. Since this flight does it so regularily, he could have a helping hand with ATC getting him in the system easily.

Having never done VFR on top, I don’t think that traffic can go through a hot MOA since it is an IFR clearance, maybe somebody else can chime in.

Allen


#16

Tracon can also issue a cancellation as soon as you accept a “Visual Approach” even if you are 10+ miles out. I’ve seen that on my trips before.


#17

Sometimes; other times they’ll issue an estimated arrival 15 minutes in the future.


#18

In my experiences, I’d suspect ONLY if you cancel the IFR after you accept the visual, will tracon cancel it 10 miles out.

They can’t cancel it just based on you accepting the visual, you have to either cancel the IFR with center, approach controller or FSS after landing.

(I.E center, I would like to cancel my IFR and center replies IFR cancellation received squawk VFR, have a good day or they more often then not will advise you to “cancel IFR this frequency or FSS after landing” at an uncontrolled airport without a remote transmitter to a nearby ATC component.


#19

By the time I got doen reading the 1269 pages, they would have two more pages of change history to add to their 11 pages of change history. Glad I am not printing this puppy!

Thanks for the link!

Allen


#20

In a Tracon environment they can and do. When you accept a “Visual Approach” you have accepted responsibility for your own traffic separation, and alleviated the controller of that responsibility. You have essentially cancelled IFR and become VFR traffic in (my example Class B) controlled airspace.

http://www2.faa.gov/airports_airtraffic/air_traffic/publications/atpubs/ATC/Chp7/atc0704.html#GhI17cJACK

asrs.arc.nasa.gov/publications/d … visual.htm

ATC’s IFR separation requirements are eliminated and the pilot assumes the burden for maintaining adequate separation.