# Flight Schedules: Why such a large difference in flight time?
**URL:** https://boards.straightdope.com/t/flight-schedules-why-such-a-large-difference-in-flight-time/586812
**Category:** Factual Questions
**Created:** [June 25, 2011, 8:41am UTC](https://boards.straightdope.com/t/flight-schedules-why-such-a-large-difference-in-flight-time/586812 "2011-06-25T08:41:20Z")
**Posts on this page:** 13
**Page:** 1
### Author:  [@Dahnlor](https://boards.straightdope.com/u/Dahnlor)
#### Post date: [June 25, 2011, 8:41am UTC](https://boards.straightdope.com/t/flight-schedules-why-such-a-large-difference-in-flight-time/586812/1 "2011-06-25T08:41:20Z")
So I was looking at flight schedules between L.A. and Kiev, and I find a route on Aeroflot that connects through Moscow, and I notice something peculiar about the schedule between Moscow and Kiev:
Aeroflot Russian Airlines 1802
Depart Moscow, Russia (SVO): 10:50pm
Arrive Kiev, Ukraine (KBP): 10:30pm
time=0hr 40min - Airbus A321
Aeroflot Russian Airlines 1803
Depart Kiev, Ukraine (KBP): 8:05am
Arrive Moscow, Russia (SVO): 11:40am
time=2hr 35min - Airbus A321
It struck me as odd that it would take nearly 2 hours longer to return to Moscow than it took to get to Kiev, or four times as long. Every other flight on Aeroflot showed a similar difference. At first I thought it might have something to do with how busy either airport is or the different times of day, but then I found the same round trip on Aerosvit:
Aerosvit Airlines 416
Depart Moscow, Russia (SVO): 10:40pm
Arrive Kiev, Ukraine (KBP): 11:20pm
1hr 40min - Boeing 737
Aerosvit Airlines 405
Depart Kiev, Ukraine (KBP): 7:00am
Arrive Moscow, Russia (SVO): 9:35am
1hr 35min - Boeing 737
This looks more like what I would expect, pretty much the same time either way. Is there a reason Aeroflot is so much faster one way than another?
---
### Author:  [@jjimm](https://boards.straightdope.com/u/jjimm)
#### Post date: [June 25, 2011, 9:19am UTC](https://boards.straightdope.com/t/flight-schedules-why-such-a-large-difference-in-flight-time/586812/2 "2011-06-25T09:19:41Z")
Departure and arrival times are shown in the local time zone.
Moscow is UTC +4 whereas Kiev is UTC +3. So 22.40 in Moscow is 21.40 in Kiev. The plane arrives at 23.20, making the flight time 1 hour 40 minutes.
On the return, when the time is 08.05 in Kiev it’s 09.05 in Moscow. The flight time is 1 hour 35 minutes.
---
### Author:  [@Elmer\_J.Fudd](https://boards.straightdope.com/u/Elmer_J.Fudd)
#### Post date: [June 25, 2011, 9:23am UTC](https://boards.straightdope.com/t/flight-schedules-why-such-a-large-difference-in-flight-time/586812/3 "2011-06-25T09:23:37Z")
It may be a three point flight. I took a flight from London to Palermo and there was a stop in between in Catania. On the flight back, the plane had already made its Catania stop and I flew directly from Palermo to London.
---
### Author:  [@Hypnagogic\_Jerk](https://boards.straightdope.com/u/Hypnagogic_Jerk)
#### Post date: [June 25, 2011, 9:54am UTC](https://boards.straightdope.com/t/flight-schedules-why-such-a-large-difference-in-flight-time/586812/4 "2011-06-25T09:54:18Z")
> [@jjimm](#):
>
> Departure and arrival times are shown in the local time zone.
This is true, but if you look at the figures in the OP, with Aeroflot the flight supposedly takes off at 22:50 (Moscow time) and arrives at 22:30 (Kiev time), for a flight time of 40 minutes, as indicated. On the return trip, it takes off at 8:05 (Kiev time) and lands at 11:40 (Moscow time), for a flight time of 2:35. Aerosvit, OTOH, has flight times of **1** :40 for the first trip, and **1** :35 for the return trip.
My guess would be a mistake in the schedule, due to a miscalculation of the difference in time zones.
---
### Author:  [@Alley\_Dweller](https://boards.straightdope.com/u/Alley_Dweller)
#### Post date: [June 25, 2011, 9:58am UTC](https://boards.straightdope.com/t/flight-schedules-why-such-a-large-difference-in-flight-time/586812/5 "2011-06-25T09:58:07Z")
The distance from SVO to KBP is [472 miles.](http://www.webflyer.com/travel/mileage_calculator/getmileage.php?city=svo&city=kbp&city=&city=&city=&city=&bonus=0&bonus_use_min=0&class_bonus=0&class_bonus_use_min=0&promo_bonus=0&promo_bonus_use_min=0&min=0&min_type=m&ticket_price=) To cover that distance in 40 minutes, the plane would have to average 708 mph, including time to taxi to/from runway and waiting in line to take off. The maximum cruising speed of an A321 is 561 mph ([903 km/h](http://www.airliners.net/aircraft-data/stats.main?id=24)). (If you allowed 20 minutes taxi time at both airports plus waiting time, that would be 944 mph in the air.) You’d need a heck of a tailwind.
As jjimm pointed out, the first set of figures did not adjust for timezone differences properly.
---
### Author:  [@Hypnagogic\_Jerk](https://boards.straightdope.com/u/Hypnagogic_Jerk)
#### Post date: [June 25, 2011, 10:11am UTC](https://boards.straightdope.com/t/flight-schedules-why-such-a-large-difference-in-flight-time/586812/6 "2011-06-25T10:11:08Z")
I checked on Kayak, and the flight time between Moscow and Kiev should indeed be about 1:30. Here’s a typical result (from Aeroflot):
```auto
Depart Thu, Jul 7 SVO to KBP – nonstop 1h 35m
Aeroflot – Flight 185 1h 35m
Take-off Thu 9:55p SVO Moscow, Russia
Landing Thu 10:30p KBP Kiev, Ukraine
Economy | Airbus A321-100/200 (Narrow-body Jet) | 1h 35m | 472 miles | Fare code: QPX1 | 7 seats remain
Return Mon, Jul 11 KBP to SVO – nonstop 1h 30m
Aeroflot – Flight 184 1h 30m
Take-off Mon 4:50p KBP Kiev, Ukraine
Landing Mon 7:20p SVO Moscow, Russia
Economy | Airbus A321-100/200 (Narrow-body Jet) | 1h 30m | 472 miles | Fare code: QPX1 | 7 seats remain
```
So the departure and/or arrival hours in the OP are wrong. I cannot find info about flights 1802 and 1803 to figure out what the correct hours should be.
---
### Author:  [@Dahnlor](https://boards.straightdope.com/u/Dahnlor)
#### Post date: [June 25, 2011, 3:56pm UTC](https://boards.straightdope.com/t/flight-schedules-why-such-a-large-difference-in-flight-time/586812/7 "2011-06-25T15:56:45Z")
I found these schedules for flights in December, specifically December 7, 2011 for both directions for the sake of comparison, but it’s the same as other dates for these flights in December. I first found the schedule on Orbitz, where I copy and pasted all of the numbers in the OP from (including the flight time calculation, which is correct when taking the time zone change into account), then went to Aeroflot’s site and found the same schedule there. They are non-stop flights.
Seeing **Alley Dweller** ’s calculations, it looks like Aeroflot might have published an error, lest they strap rockets to their planes that are pointed at Kiev both ways. Yet the two other flights they offer on the same date also have the same apparent error (copy/pasting again Orbitz’ calculations):
Aeroflot Russian Airlines 1800
Depart Moscow, Russia (SVO): 1:20pm
Arrive Kiev, Ukraine (KBP): 12:55pm
time=35min - Airbus A321
Aeroflot Russian Airlines 1801
Depart Kiev, Ukraine (KBP): 2:30pm
Arrive Moscow, Russia (SVO): 6:00pm
time=2hr 30min - Airbus A321
So, just a typo?
---
### Author:  [@fumster](https://boards.straightdope.com/u/fumster)
#### Post date: [June 25, 2011, 4:33pm UTC](https://boards.straightdope.com/t/flight-schedules-why-such-a-large-difference-in-flight-time/586812/8 "2011-06-25T16:33:05Z")
> [@Alley\_Dweller](#):
>
> The distance from SVO to KBP is [472 miles.](http://www.webflyer.com/travel/mileage_calculator/getmileage.php?city=svo&city=kbp&city=&city=&city=&city=&bonus=0&bonus_use_min=0&class_bonus=0&class_bonus_use_min=0&promo_bonus=0&promo_bonus_use_min=0&min=0&min_type=m&ticket_price=) To cover that distance in 40 minutes, the plane would have to average 708 mph…
Maybe they are rushin’.
---
### Author:  [@simster](https://boards.straightdope.com/u/simster)
#### Post date: [June 25, 2011, 5:27pm UTC](https://boards.straightdope.com/t/flight-schedules-why-such-a-large-difference-in-flight-time/586812/9 "2011-06-25T17:27:06Z")
this is simply showing you what time you depart/arrive in local tz -
Aeroflot Russian Airlines 1800
Depart Moscow, Russia (SVO): 1:20pm
Arrive Kiev, Ukraine (KBP): 12:55pm
time=35min - Airbus A321
Notice - he’s arrivinb before he leaves - the last line is, without a doubt, a typo or miscalculation by the software.
---
### Author:  [@Hypnagogic\_Jerk](https://boards.straightdope.com/u/Hypnagogic_Jerk)
#### Post date: [June 25, 2011, 8:56pm UTC](https://boards.straightdope.com/t/flight-schedules-why-such-a-large-difference-in-flight-time/586812/10 "2011-06-25T20:56:20Z")
I think I’ve figured it out. Moscow is in time zone UTC+4 year round, while Kiev is in UTC+2 in winter and UTC+3 in summer. The departure and arrival times in the OP are correct, but the software computing the flight time is incorrectly assuming the trip is happening in summer.
From Kayak (which computes the flight time correctly), here are the flights the OP is interested in:
```auto
Depart Wed, Dec 7 SVO to KBP – nonstop 1h 40m
Aeroflot – Flight 1802 1h 40m
Take-off Wed 10:50p SVO Moscow, Russia
Landing Wed 10:30p KBP Kiev, Ukraine
Economy | Airbus A321-100/200 (Narrow-body Jet) | 1h 40m | 472 miles | Fare code: QPXOW1 | 7 seats remain
Depart Wed, Dec 7 KBP to SVO – nonstop 1h 35m
Aeroflot – Flight 1803 1h 35m
Take-off Wed 8:05a KBP Kiev, Ukraine
Landing Wed 11:40a SVO Moscow, Russia
Economy | Airbus A321-100/200 (Narrow-body Jet) | 1h 35m | 472 miles | Fare code: QPXOW | 7 seats remain
```
---
### Author:  [@Baracus](https://boards.straightdope.com/u/Baracus)
#### Post date: [June 25, 2011, 8:57pm UTC](https://boards.straightdope.com/t/flight-schedules-why-such-a-large-difference-in-flight-time/586812/11 "2011-06-25T20:57:35Z")
> [@Dahnlor](#):
>
> I found these schedules for flights in December, specifically December 7, 2011 for both directions for the sake of comparison, but it’s the same as other dates for these flights in December.
One thing to note here, according to Wikipedia, Russia moved its clocks forward an hour this spring for the last time (supposedly) and will _not_ be moving them back again this fall. Ukraine is continuing with DST as usual, so perhaps Aeroflots scheduling software is not reporting these changes correctly.
---
### Author:  [@Hypnagogic\_Jerk](https://boards.straightdope.com/u/Hypnagogic_Jerk)
#### Post date: [June 25, 2011, 9:07pm UTC](https://boards.straightdope.com/t/flight-schedules-why-such-a-large-difference-in-flight-time/586812/12 "2011-06-25T21:07:40Z")
Good catch **Baracus**. I saw on Wikipedia that Moscow was practicing year-round DST, but if it’s actually a new thing from this year it explains why some software hasn’t caught up to it yet.
---
### Author:  [@JKellyMap](https://boards.straightdope.com/u/JKellyMap)
#### Post date: [June 26, 2011, 1:23pm UTC](https://boards.straightdope.com/t/flight-schedules-why-such-a-large-difference-in-flight-time/586812/13 "2011-06-26T13:23:44Z")
😃
> [@sh1bu1](#):
>
> Maybe they are rushin’.