# Flight Time Difference **URL:** \ **Category:** General\ **Created:** [December 10, 2009, 2:17pm UTC](https://discussions.flightaware.com/t/flight-time-difference/9012 "2009-12-10T14:17:43Z")\ **Posts on this page:** 14\ **Page:** 1
**Author:** ![im4point](https://avatars.discourse-cdn.com/v4/letter/i/e8c25b/32.png) [@im4point](https://discussions.flightaware.com/u/im4point)\ **Post date:** [December 10, 2009, 2:17pm UTC](https://discussions.flightaware.com/t/flight-time-difference/9012/1 "2009-12-10T14:17:43Z")
I was the FO on these flights… Our flight time to BWI was 1:29 but flight aware shows it as 1:19 [flightaware.com/live/flight/EGF3 … /KORD/KBWI](http://flightaware.com/live/flight/EGF3970/history/20091209/1428Z/KORD/KBWI) Our flight time back to ORD was 2:06 yet flight aware shows it as 1:59 [flightaware.com/live/flight/EGF3 … /KBWI/KORD](http://flightaware.com/live/flight/EGF3991/history/20091209/1643Z/KBWI/KORD) Where do these times come from? My times come right from ACARS and match perfectly with our clock in the airplane. And yes, I am talking about FLIGHT time, not gate to gate. Thanks ---
**Author:** ![porterjet](https://sea1.discourse-cdn.com/flex019/user_avatar/discussions.flightaware.com/porterjet/32/73393_2.png) [@porterjet](https://discussions.flightaware.com/u/porterjet)\ **Post date:** [December 10, 2009, 3:13pm UTC](https://discussions.flightaware.com/t/flight-time-difference/9012/2 "2009-12-10T15:13:33Z")
Flight Aware uses ATC time, not ACARS time. ATC time, as I understand it, starts and stops when somebody in the tower tells the computer you have lifted off or landed. If that specialist is busy cutting a new ATIS or downstairs using the facilities the times may be way off. ---
**Author:** ![pthomas745](https://sea1.discourse-cdn.com/flex019/user_avatar/discussions.flightaware.com/pthomas745/32/126086_2.png) [@pthomas745](https://discussions.flightaware.com/u/pthomas745)\ **Post date:** [December 10, 2009, 4:11pm UTC](https://discussions.flightaware.com/t/flight-time-difference/9012/3 "2009-12-10T16:11:14Z")
No. There isn’t a tower controller who stands there and “tells the computer” a departure time or arrival. Its pretty much automatic. When the radar acquires an aircraft’s beacon code and the track starts ( the data block acquires) the computer gets a departure message and the race is on. ---
**Author:** ![porterjet](https://sea1.discourse-cdn.com/flex019/user_avatar/discussions.flightaware.com/porterjet/32/73393_2.png) [@porterjet](https://discussions.flightaware.com/u/porterjet)\ **Post date:** [December 10, 2009, 4:29pm UTC](https://discussions.flightaware.com/t/flight-time-difference/9012/4 "2009-12-10T16:29:03Z")
Yes. Let’s call it sometimes. You are right when radar can see you all the way to the ground, otherwise somebody has to tell the computer you are airborne, or landed as the case may be. I see this all the time at airports where low altitude radar coverage is non existent. In the rare case your transponder is inop or the wrong code is inserted a controller still has to tell the system you are airborne. I also just remembered the FA times are dithered and may not be accurate to the minute. This is most likely the case in the OPs flights, ( BWI to ORD) ---
**Author:** ![pthomas745](https://sea1.discourse-cdn.com/flex019/user_avatar/discussions.flightaware.com/pthomas745/32/126086_2.png) [@pthomas745](https://discussions.flightaware.com/u/pthomas745)\ **Post date:** [December 10, 2009, 4:47pm UTC](https://discussions.flightaware.com/t/flight-time-difference/9012/5 "2009-12-10T16:47:57Z")
Sorry, Mr. P, didn’t mean to sound hostile. All I was trying to point out is the system is automated to a very great degree, and there isn’t a position in a tower assigned to press a button to tell a computer to send a departure message. Controllers in a radar environment don’t have to send out a departure message. It happens automatically when the aircraft data block is acquired. And, yes, the rare wrong beacon code or the even more rare bad transponder would mean a controller would have to start a new track. ---
**Author:** ![porterjet](https://sea1.discourse-cdn.com/flex019/user_avatar/discussions.flightaware.com/porterjet/32/73393_2.png) [@porterjet](https://discussions.flightaware.com/u/porterjet)\ **Post date:** [December 10, 2009, 5:28pm UTC](https://discussions.flightaware.com/t/flight-time-difference/9012/6 "2009-12-10T17:28:37Z")
Oh, I didn’t take it as hostile. I guess it’s been a while since I visited a tower. I imagine things are a lot more automated now, I remember one of the controllers having to input some sort of arrival message to the computer when an IFR flight landed. ---
**Author:** ![mduell](https://sea1.discourse-cdn.com/flex019/user_avatar/discussions.flightaware.com/mduell/32/115680_2.png) [@mduell](https://discussions.flightaware.com/u/mduell)\ **Post date:** [December 10, 2009, 6:11pm UTC](https://discussions.flightaware.com/t/flight-time-difference/9012/7 "2009-12-10T18:11:32Z")
Which end is off? EGF3970: Departure 12/09/2009 15:55:05 actualDepartureTime 12/09/2009 15:55:00 Arrival 12/09/2009 17:25:50 time 12/09/2009 17:14:00 EGF3991: Departure 12/09/2009 18:13:49 actualDepartureTime 12/09/2009 18:14:00 Arrival 12/09/2009 20:12:46 time 12/09/2009 20:13:00 The timestamps are all from the FAA, we received the messages about 5 minutes later. ---
**Author:** ![porterjet](https://sea1.discourse-cdn.com/flex019/user_avatar/discussions.flightaware.com/porterjet/32/73393_2.png) [@porterjet](https://discussions.flightaware.com/u/porterjet)\ **Post date:** [December 10, 2009, 6:28pm UTC](https://discussions.flightaware.com/t/flight-time-difference/9012/8 "2009-12-10T18:28:50Z")
There is the same type of problem when comparing the BBC with the GPS clock. How in the world can the US DOD be 13 seconds off? 😃 ---
**Author:** ![im4point](https://avatars.discourse-cdn.com/v4/letter/i/e8c25b/32.png) [@im4point](https://discussions.flightaware.com/u/im4point)\ **Post date:** [December 10, 2009, 8:05pm UTC](https://discussions.flightaware.com/t/flight-time-difference/9012/9 "2009-12-10T20:05:00Z")
> [@mduell](#): > > Which end is off? > > EGF3970: > Departure 12/09/2009 15:55:05 > actualDepartureTime 12/09/2009 15:55:00 > > Arrival 12/09/2009 17:25:50 > time 12/09/2009 17:14:00 > > EGF3991: > Departure 12/09/2009 18:13:49 > actualDepartureTime 12/09/2009 18:14:00 > > Arrival 12/09/2009 20:12:46 > time 12/09/2009 20:13:00 > > The timestamps are all from the FAA, we received the messages about 5 minutes later. I show: 3970 (LOCAL TIMES) DEP: 0951 ARR: 1220 3991 DEP: 1311 ARR: 1417 ---
**Author:** ![im4point](https://avatars.discourse-cdn.com/v4/letter/i/e8c25b/32.png) [@im4point](https://discussions.flightaware.com/u/im4point)\ **Post date:** [January 3, 2010, 11:57pm UTC](https://discussions.flightaware.com/t/flight-time-difference/9012/10 "2010-01-03T23:57:59Z")
Here is another example of times that are off… [flightaware.com/live/flight/EGF3 … /KCAE/KDFW](http://flightaware.com/live/flight/EGF3366/history/20100103/1118Z/KCAE/KDFW) Actual Dep 1111Z Actual Arr 1409Z Total: 02:58 Flight Aware has: Dep 1112Z Arr 1402Z Total 02:50 ❓ ---
**Author:** ![deef1999](https://avatars.discourse-cdn.com/v4/letter/d/a4c791/32.png) [@deef1999](https://discussions.flightaware.com/u/deef1999)\ **Post date:** [January 4, 2010, 12:29am UTC](https://discussions.flightaware.com/t/flight-time-difference/9012/11 "2010-01-04T00:29:48Z")
> [@im4point](#): > > Here is another example of times that are off… > > [flightaware.com/live/flight/EGF3 … /KCAE/KDFW](http://flightaware.com/live/flight/EGF3366/history/20100103/1118Z/KCAE/KDFW) > > Actual Dep 1111Z > Actual Arr 1409Z > Total: 02:58 > > Flight Aware has: > Dep 1112Z > Arr 1402Z > Total 02:50 > > ❓ Is [THIS](http://www.youtube.com/watch?v=RayMaswju1A) accurate? ---
**Author:** ![will744](https://avatars.discourse-cdn.com/v4/letter/w/779978/32.png) [@will744](https://discussions.flightaware.com/u/will744)\ **Post date:** [January 4, 2010, 1:47am UTC](https://discussions.flightaware.com/t/flight-time-difference/9012/12 "2010-01-04T01:47:46Z")
Thanks deef. I love this video! 😃 ---
**Author:** ![im4point](https://avatars.discourse-cdn.com/v4/letter/i/e8c25b/32.png) [@im4point](https://discussions.flightaware.com/u/im4point)\ **Post date:** [January 4, 2010, 9:39pm UTC](https://discussions.flightaware.com/t/flight-time-difference/9012/13 "2010-01-04T21:39:01Z")
Nope, that’s not accurate either. Video shows $20,736 first year. I made 31k my first year and upgrade time is 7 years. 😛 ---
**Author:** ![deef1999](https://avatars.discourse-cdn.com/v4/letter/d/a4c791/32.png) [@deef1999](https://discussions.flightaware.com/u/deef1999)\ **Post date:** [January 4, 2010, 10:26pm UTC](https://discussions.flightaware.com/t/flight-time-difference/9012/14 "2010-01-04T22:26:37Z")
> [@im4point](#): > > Nope, that’s not accurate either. > > Video shows $20,736 first year. I made 31k my first year and upgrade time is 7 years. 😛 Yeah, too bad there is no real union, you guys deserve more, much more.