contrails67
Topic Author
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Flying Time

Thu Jun 21, 2012 1:28 pm

I know that airlines pad their schedules to account for delays and weather, but how can I get a proper determination of actual flying time:

1. When airlines post their departure and arrival time, I assume that to make themselves look good, the departure time is the moment they left the gate and the arrival time is the moment the wheels touch down on the runway at the destination. Can someone verify?

2. Why do so many different tracking websites have different arrival and departure times? Should we assume that the departure and arrival time at the airline website is the most accurate?
 
Goldenshield
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RE: Flying Time

Thu Jun 21, 2012 3:15 pm

Quoting contrails67 (Thread starter):
When airlines post their departure and arrival time, I assume that to make themselves look good, the departure time is the moment they left the gate and the arrival time is the moment the wheels touch down on the runway at the destination. Can someone verify?

Departure time = Block out of the gate.
Arrival time = Block into the gate.

Flight time = (Planned) Wheels up to Wheels down.

Quoting contrails67 (Thread starter):
Why do so many different tracking websites have different arrival and departure times? Should we assume that the departure and arrival time at the airline website is the most accurate

The arrival and departure time of the airline itself will be most accurate. Other sites are deriving their information from 3rd parties, such as Flightaware.
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roseflyer
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RE: Flying Time

Thu Jun 21, 2012 3:51 pm

Quoting contrails67 (Thread starter):
1. When airlines post their departure and arrival time, I assume that to make themselves look good, the departure time is the moment they left the gate and the arrival time is the moment the wheels touch down on the runway at the destination. Can someone verify?

Typically it is from parking brake release to parking brake set. It doesn’t always work that way, but that is usually how the flight duration is set and is what airlines publish as arrival and departure times if they publish actual times on their website.

The purpose of padding schedules goes beyond just looking good in the Arrival 14 stats. Airlines typically monitor Arrival within 14 minutes, Departure at 0, Departure within 15, Departure within 120, Departure over 120 and Cancellations. All the numbers are used in different areas. For example delays under 15 are typically because of airport operations loading the passengers, short turnaround times, maintenance deferrals, cargo loading, etc. Delays over 120 minutes are for serious mechanical problems that take time to repair and can’t be deferred (Fuel, Flight Controls, Engines, etc).

Padding the schedules helps the airline prevent passenger misconnects. However it can result in airplanes with longer block time due to gate availability, and lower utilization. Every airline is different. Also departures at certain times of the day are padded more for anticipated airport delays. For example on JFK, block times range from 5:50 to 6:15 depending on airline and time of day.
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Viscount724
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RE: Flying Time

Fri Jun 22, 2012 5:06 am

Quoting contrails67 (Thread starter):
When airlines post their departure and arrival time, I assume that to make themselves look good, the departure time is the moment they left the gate and the arrival time is the moment the wheels touch down on the runway at the destination.
Quoting Roseflyer (Reply 2):
For example on JFK, block times range from 5:50 to 6:15 depending on airline and time of day.

Not sure what route you're referring to (maybe JFK-LAX?), but I've noted that on LHR-JFK, BA has a 744 and DL a 764 departing 5 minutes apart at 1300 and 1305 but DL's block time is 40 minutes longer (BA arrives 1530 and DL 1615).

I know the 744 is faster than the 767 but I doubt the speed difference would account for 40 minutes on a relatively short transatlantic sector like JFK-LHR. I expect the 40 minute longer DL published block time deters some passengers from choosing DL.
 
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Starlionblue
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RE: Flying Time

Fri Jun 22, 2012 6:51 am

Quoting contrails67 (Thread starter):
2. Why do so many different tracking websites have different arrival and departure times? Should we assume that the departure and arrival time at the airline website is the most accurate?


The airline is not necessarily the most accurate. It depends on where the data is gathered and how quickly it is updated.

If you look at "Extended Details" for a flight on www.flightstats.com it will show time at gate and time at runway (estimates and actual) separately.
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roseflyer
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Joined: Fri Feb 13, 2004 9:34 am

RE: Flying Time

Fri Jun 22, 2012 5:54 pm

Quoting Viscount724 (Reply 3):

Not sure what route you're referring to (maybe JFK-LAX?), but I've noted that on LHR-JFK, BA has a 744 and DL a 764 departing 5 minutes apart at 1300 and 1305 but DL's block time is 40 minutes longer (BA arrives 1530 and DL 1615).

Sorry I was referring to JFK-LAX.

For JFK-LHR, 40 minutes is about right to accommodate the 747 vs 767 speed difference. The 767 does take about 30-40 minutes longer on a route of that duration. For those 747/A380/777 pilots out there, I am sure they are always passing the 757s and 767s on transatlantic runs. The biggest difference I know of is SFO-NRT. Actual flight time difference between the DL 767 and UA 747 is on average 50-60 minutes.
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