4/07/2008 - Why Can't I Fly When I Want To Fly?
A question commonly asked by travelers is "Why can't I fly when I want to fly?"
As I sit here on a wall, on the edge of the San Francisco Bay, looking out over San Francisco (SFO) Int'l Airport's tandem runways (28L/28R) watching the early morning west coast-to-east coast transcontinental flights line up and depart I decided this was a good time to answer this question.
In the past month I have received a number of e-mails from photographers seeking to find out why they can't fly certain routes at certain times of the day that are convenient to them. I'm not sure why there has been an influx of this question, but clearly this is a question on many people's minds.
In reality there are dozens of answers to this question depending on each individual scenario. But in many cases the reason why people cannot fly when they want to fly has to do with two factor
1) Length of Flight
2) Time-Zone Shifts
When airlines plan their routes they have to account for simple factors such as departure and arrival time. A good example of this is flights between New York's JFK (JFK) and London's Heathrow (LHR). For travelers there are only two times of the day you can fly this route, between 7:30am and 9:00am or between 6:00pm and 11:30pm. Conversely for those seeking to fly from Heathrow back to JFK they can depart nearly all day long from 8:30am until 8:05pm with flight never really more than 90 minutes apart.
Why can you only go to London in the early morning or the evening and return all day? Simple, it involves traveling with the time zones. If you depart JFK at 10:00am you'll arrive at 10:00pm, which is why many business travelers often fly out around 6:00pm or 7:00pm to arrive in the morning at the start of the business day. These times are because you are flying east, which are 'against' the time-zones.
When you fly 'against' a time zone is when you are flying in a direction that adds time to your day. If you depart JFK at 8:30am, it is already 1:30pm at LHR. The average flight time between JFK and LHR is 7hrs 30min (flight times depends on the type of aircraft flown, such as 777-200 takes 7hrs 25min while a 757-200 may take 8hrs, then you factor in the airline's 'blocked flight time', etc etc). So if you're 8:30am departure is really a "1:30pm departure" puts you in at 9:00pm, or approx 12hr 30min after you departed instead of 7hrs 30min after you departed.
If an airline were to offer a 2:00pm flight between JFK and LHR you'd arrive around 2:00am the following day. This would mean passengers would arrive in a closed airport with no service between the airport and the city, leaving passengers stranded for 3 hours waiting for the airport to open again.
The return flights are easier to manage because flights headed west are flying "with the time zone." A flight departing LHR at 8:30am arrives at a reasonable 11:00am and an 8:00pm departure also arrives at a reasonable 10:30pm
If you watch airports departures during the day you see a shift in 'tails' and aircraft routes throughout the day. Yesterday at SFO looking out I noticed the Japan/China/Korea flights all depart in clusters, right around the same time the Paris/Amsterdam/Dublin/Frankfurt/London flights arrive in the afternoon. Around this time you starts watching the north-south traffic and 'mid-continent' flights increase. It is not random that the majority of the airlines flying certain routes operate on very similar schedules. These airline are all fighting the same forces of 'linear time & time-zones." An airline's schedule must not only meet passenger needs, but also the logical need to depart and arrive within a practical time period.
I won't get into the factor of the international dateline combines with time zones but I will say this......I always love flying from Nagoya, Japan (NGO) to Honolulu, Hawaii (HNL) and landing 12 hours before I have taken off (aren't time zones and the international date line fun?).
.................Keep this in mind when you fly from New York's JFK to Los Angeles' LAX on a business trip and have a multitude of options in the morning, but get frustrated when you're trying to book a late afternoon flight from LAX back to JFK and you can't find any flights available.
.........and for no reason at all, at the end of the post is a photo I shot from the wall I am sitting on of a Northwest Airlines Airbus A319 climbing out off of SFO's Runway 28L in front of the San Francisco skyline
Happy Flying!
--Click Image To Enlarge It--
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