Sponsor Message:
Civil Aviation Forum
My Starred Topics | Profile | New Topic | Forum Index | Help | Search 
Why Do Flight Times Vary So Much?  
User currently offlineCoolGuy From United States of America, joined Jan 2005, 414 posts, RR: 0
Posted (8 years 2 weeks 6 days 21 hours ago) and read 8223 times:

For example, one flight EWR-CLE can take 1:44, but another at a different (busier, probably) time, takes 1:59

Also, LGA-ORD may take 2:30, but the reverse is 1:56.

Does traffic really affect the scheduled times that much?

10 replies: All unread, jump to last
 
User currently offlineLamedianaranja From Venezuela, joined Nov 2004, 1246 posts, RR: 20
Reply 1, posted (8 years 2 weeks 6 days 20 hours ago) and read 8208 times:

It depends on taxi-times too. AMS-LHR takes 1.30 hours in the timetable but actual flying time is almost never more than 50 minutes. As it's such a busy route the airline prefers to take that into account right away and not always arrive 'late'.

The difference in returns may also be caused by prevailing wind directions.



I wish that all skies were orange and blue!!
User currently offlineSonOfACaptain From United States of America, joined May 2004, 1747 posts, RR: 6
Reply 2, posted (8 years 2 weeks 6 days 20 hours ago) and read 8198 times:

They want to screw with your mind.  angel 

Seriously though, there are many factors that effect the "flight time" of a flight. Commercial flying isn't as simple as flying directly to your destinations. You have to take account of traffic (both in the air and on ground), taxi time, and many, many other factors.

-SOAC



Non Illegitimi Carborundum
User currently offlineEHHO From Bulgaria, joined Dec 2005, 815 posts, RR: 7
Reply 3, posted (8 years 2 weeks 6 days 20 hours ago) and read 8180 times:

It depends very much on the air corridors the flight gets assigned. When I flew PEK-AMS and AMS-PEK earlier this year, on the way there we took a southern route flying over Moscow and Omsk, while on the way back it was over Surgut and St. Petersburg, hundreds of miles to the north.

Check these recent QF LAX-JFK-LAX flights. On some days the fly over Missouri, on others near the state line between the Dakota's. Big difference:

Flightaware QF108



"Get your facts first. Then you may distort them as much as you please" -- Mark Twain
User currently offlineHT From Germany, joined May 2005, 6525 posts, RR: 23
Reply 4, posted (8 years 2 weeks 6 days 19 hours ago) and read 8153 times:

Quoting CoolGuy (Thread starter):

For such short flights as mentioned in your original post, like LAMEDIANARANJA pointed out taxi times ( = waiting in queues ) can be major factor if busy airports are involved.

For longhaul flights (especially East <-> West) , the difference between haed and tail winds make the difference. These presisting winds (aka. Jetstreams) also have an influance on the exact routing.
Flights from Europe to the U.S.-West coast usually fly much further north than on the return: This way they make the best out of trying to avoid head winds (fyling west) and making use of tail wind (flying east).
-HT



Carpe diem ! Life is too short to waste your time ! Keep in mind, that today is the first day of the rest of your life !
User currently offlineTristarSteve From Sweden, joined Nov 2005, 4052 posts, RR: 33
Reply 5, posted (8 years 2 weeks 6 days 19 hours ago) and read 8125 times:

Also the winds on the day can make a huge differencr.
LHR-ARN takes about 2hr 10mins.
But I have seen flight times of 1hr 50mins up to 2hr 45mins, just because of the wind.


User currently offlineFlyingfool From Netherlands, joined May 2005, 441 posts, RR: 2
Reply 6, posted (8 years 2 weeks 6 days 14 hours ago) and read 7988 times:

For excample, I've travelled RTM-DUB and EIN-DUB, RTM-DUB took 1:50 minutes and EIN-DUB (which is a longer flight in distance) took only about 1:15 minutes on almost the same routing...
This has all to do with strong headwinds.

Regards, Flyingfool


User currently offlineBMIFlyer From UK - England, joined Feb 2004, 8810 posts, RR: 58
Reply 7, posted (8 years 2 weeks 6 days 14 hours ago) and read 7983 times:

Taxi times
Prevailing winds
Aircraft type
Traffic Patterns
Weather

You name it, it all happens, and can affect flight times in big ways  Smile



Lee



Sometimes You Can't Make It On Your Own
User currently offlineBistro1200 From United States of America, joined Oct 2003, 337 posts, RR: 4
Reply 8, posted (8 years 2 weeks 6 days 14 hours ago) and read 7962 times:

From what I've heard, airlines typically use 55-65% reliability in their block times. This means that of 100 flights, 55-65 of them arrive at or under the published block time. Northwest I heard went to 50% block times, where half of all flights are automatically late. This was to save pilot costs.

It's a toss-up though, since lowering the block time makes for less crew costs (most crews are paid either the scheduled hours or flown hours, whichever is greater) while hurting on-time reliability and likely missed connections. Raising the block time makes for better on-time at the expense of crew costs and connections.

Don't forget connections in this equation. Say you are flying LAX-JFK-Europe, and your connection is planned right at the minimum connection time, say 45 minutes. If your airline uses 50% reliability, then you have a 50% chance of being late for your European departure at JFK, even if you leave LAX on time. Raising that to 65% means raising the block time, but now your connection time is only 38 minutes (example), so your routing is no longer legal. Retiming the LAXJFK flight might work, but now you may miss the inbound traffic from HNL or SAN. Cutting the minimum connection time is also something you don't want to do (especially to International flights) since that will cause in increase in DB's and general bad feelings by the passengers that missed it.

This is the stuff that airline managers have to figure out regularly.



Measure to the millimeter, mark with a crayon, cut with an axe.
User currently offlineCs03 From United States of America, joined Oct 2003, 413 posts, RR: 0
Reply 9, posted (8 years 2 weeks 6 days 13 hours ago) and read 7920 times:
Support Airliners.net - become a First Class Member!

All the above replies are correct for why airlines "pad" the schedule.

User currently offlineCkfred From United States of America, joined Apr 2001, 5293 posts, RR: 1
Reply 10, posted (8 years 2 weeks 6 days 4 hours ago) and read 7752 times:

I haven't looked in a while, but AA flights on ATL-ORD used to have an extra 10 to 15 minutes during the evening rush hour, because those flights almost always got stuck in a long line of departures waiting for takeoff at ATL.

Quoting EHHO (Reply 3):
It depends very much on the air corridors the flight gets assigned. When I flew PEK-AMS and AMS-PEK earlier this year, on the way there we took a southern route flying over Moscow and Omsk, while on the way back it was over Surgut and St. Petersburg, hundreds of miles to the north.

Even on shorter routes, there can be a difference. On ORD-ATL, the southbound flights generally fly from ORD to Danville, IL, then to Nashville, TN, then enter into the ATL pattern from the west.

Northbound, planes generally depart on a north-northwest heading, going to Chattanooga, TN, Louisville, KY, Indianapolis, IN, then entering the ORD pattern from over Lake Michigan.

The southbound flight usually runs 5 to 10 minutes shorter, because it's closer to being a straight flight path than the northbound routing.


Top Of Page
Forum Index

This topic is archived and can not be replied to any more.

Printer friendly format

Similar topics:More similar topics...
Why Do Ticket Agents Type So Much? posted Sat Jul 31 2004 05:06:56 by Cory6188
Why Do People Like Trijets So Much? posted Wed Sep 19 2001 12:47:01 by B777-777X
Why Are US Carriers In So Much Trouble? posted Tue Aug 30 2005 09:34:06 by B787
Why Is Frank Lorenzo Hated So Much? posted Wed Jun 15 2005 06:31:08 by IslandHopperCO
Why Does WN Like BWI So Much? posted Tue Sep 14 2004 00:07:21 by Usairways16bwi
Why Exactly Is USAir In So Much Financial Trouble? posted Fri Aug 13 2004 21:45:09 by Shuttledweller
Why Is Tom Bradley Hated So Much? posted Wed Jul 28 2004 01:30:19 by Planecrazy2
Why Do Flight Numbers Change? posted Wed Jul 21 2004 21:44:49 by AVPOH77
Why Is MEA Suddenly Getting So Much Publicity? posted Sat Mar 13 2004 18:40:31 by Nycfuturepilot
Why Are One-way Tickets So Much More Expensive? posted Mon Dec 15 2003 23:53:13 by Ssides