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Topic: 11:59 Pm Vs Midnight Departures, Double Per Diem?
Username: ogshelly
Posted 2012-09-03 18:06:22 and read 6722 times.

I wonder why not midnight departures instead of 11:59PM, very soon those will be at11:59:59 PM. Examples are UA1046 IAH-CCS, or UA1009 IAH-BOG. With airliners pinching every penny, I doubt double per diem is allowed, if it is.....great! Flying one day and arriving a day later gives me an extra minute of jet lag. Anyone?

Topic: RE: 11:59 Pm Vs Midnight Departures, Double Per Diem?
Username: KaiGywer
Posted 2012-09-03 18:09:25 and read 6713 times.

I think most crews are paid per hour away from base regardless, so the one minute won't mean anything.

Topic: RE: 11:59 Pm Vs Midnight Departures, Double Per Diem?
Username: United1
Posted 2012-09-03 18:11:33 and read 6692 times.

Quoting ogshelly (Thread starter):

I wonder why not midnight departures instead of 11:59PM, very soon those will be at11:59:59 PM.

Flights are scheduled that way so that passengers do not show up at noon instead of midnight...

Topic: RE: 11:59 Pm Vs Midnight Departures, Double Per Diem?
Username: jbmitt
Posted 2012-09-03 18:15:50 and read 6668 times.

I think it also has to do with the date.. a 12am departure adds confusion as to whether its the day before or day off. On booking engines it can be confusing because red eyes are typically the last flight of the day, not the first.

Topic: RE: 11:59 Pm Vs Midnight Departures, Double Per Diem?
Username: LAXintl
Posted 2012-09-03 18:27:46 and read 6611 times.

Also most airlines schedule in UTC time not local, so it does not matter what the local time is.

Timings like 23:59 are commercially driven for passenger convenience.

Topic: RE: 11:59 Pm Vs Midnight Departures, Double Per Diem?
Username: bestwestern
Posted 2012-09-03 18:31:49 and read 6587 times.

Because passengers know that 23:59 on Wednesday is a flight on Wednesday evening.

It is well known that a midnight departure time is a real confusion for people - do they turn up on a Tuesday to fly at midnight or on a Wednesday to fly at midnight.

Topic: RE: 11:59 Pm Vs Midnight Departures, Double Per Diem?
Username: GoBoeing
Posted 2012-09-03 18:35:40 and read 6578 times.

This very issue helped me get home from Tel Aviv in business class.

It's good news for non-revs that know what day it is.  

Topic: RE: 11:59 Pm Vs Midnight Departures, Double Per Diem?
Username: ogshelly
Posted 2012-09-03 18:43:04 and read 6570 times.

Quoting jbmitt (Reply 3):

I agree a 100%, I missed my flight BOG-IAH at the time it was at 12:15 AM, so it really confused me, as the Bogota-Houston's departure used to be or continues so at 8 AM. I confess I am now very careful. It makes a lot of sense the 11:59 PM schedule, I see it clearly now. You guys are smart!

Topic: RE: 11:59 Pm Vs Midnight Departures, Double Per Diem?
Username: flyingturtle
Posted 2012-09-04 03:04:11 and read 6388 times.

Quoting ogshelly (Reply 7):
12:15 AM

Who would confuse that with 0:15 in the morning? Or should "12:15" AM (for "quarter past noon") really be "12:15 PM", because the morning lasts from midnight to noon (which are exactly twelve hours, or half a day), so any minute past noon should be called PM...

In the 24-hour-format, a daytime like 24 hours and xx does not exist. So there shouldn't be a daytime like 12 hours and xx minutes in the 12-hour-format?

Well, change to our 24 hour format. Thank you. You've already learnt to use it in the armed forces. 

I understand the other issue though:

Quoting bestwestern (Reply 5):
Because passengers know that 23:59 on Wednesday is a flight on Wednesday evening.

David

Topic: RE: 11:59 Pm Vs Midnight Departures, Double Per Diem?
Username: ZSOFN
Posted 2012-09-04 05:04:55 and read 6338 times.

Quoting flyingturtle (Reply 8):
Who would confuse that with 0:15 in the morning? Or should "12:15" AM (for "quarter past noon") really be "12:15 PM", because the morning lasts from midnight to noon (which are exactly twelve hours, or half a day), so any minute past noon should be called PM...

12:15am *IS* 0:15 in the morning / quarter past midnight - you seem to have it the wrong way round.

Either way - I'm all for universal use of the 24 hour clock (much more commonly used here in the UK than the US already).

Topic: RE: 11:59 Pm Vs Midnight Departures, Double Per Diem?
Username: CosmicCruiser
Posted 2012-09-04 05:29:49 and read 6326 times.

I can't imagine someone booking a flight and not knowing when it departed.

Topic: RE: 11:59 Pm Vs Midnight Departures, Double Per Diem?
Username: flyingturtle
Posted 2012-09-04 05:54:54 and read 6318 times.

Quoting ZSOFN (Reply 9):
12:15am *IS* 0:15 in the morning / quarter past midnight - you seem to have it the wrong way round.

I'll never book a flight to your country, ever again...  Wow!

On the 24 hour clock, 24 hours isn't allowed. So, a 12 on the 12 hour clock shouldn't exist, too. 0.15 AM is unambiguous - it's 15 minutes after the day started, 15 minutes past "zero".

11:59 AM is one minute before noon. So, 12 AM is noon. Therefore, 12:15 is fifteen minutes after noon... argh. 
Quoting CosmicCruiser (Reply 10):
I can't imagine someone booking a flight and not knowing when it departed.

Various flight dispatches here can tell you otherwise. A flight leaving at 1:00 on December 22nd leaves 1 hour after the day (22nd of Dec) began. To many people, 1:00 still belongs to the old day and the concept of having to pass the "night" at an airport doesn't make sense to them.

David

Topic: RE: 11:59 Pm Vs Midnight Departures, Double Per Diem?
Username: Roseflyer
Posted 2012-09-04 06:08:13 and read 6309 times.

Quoting flyingturtle (Reply 11):
On the 24 hour clock, 24 hours isn't allowed. So, a 12 on the 12 hour clock shouldn't exist, too. 0.15 AM is unambiguous - it's 15 minutes after the day started, 15 minutes past "zero".

I think you are pointing out the problem. There is not an international standard definog a 12 or 24 hour clock that is widely used. What might make sense in Switzerland would confuse most Americans who have never seen 015 as a time and don't know te 24 hour clock and get confused. Most airlines in the US avoid 0000-0100 departures.

Topic: RE: 11:59 Pm Vs Midnight Departures, Double Per Diem?
Username: CosmicCruiser
Posted 2012-09-04 08:39:13 and read 6247 times.

Quoting flyingturtle (Reply 11):
Various flight dispatches here can tell you otherwise.

After 30 yrs at my present co. I can say the converting the UTC back to local has had me thinking twice more than once but never was a no show. To me the easiest one to screw up was say a 0345Z dept which is really 1045PM local the night before.

Topic: RE: 11:59 Pm Vs Midnight Departures, Double Per Diem?
Username: Viscount724
Posted 2012-09-04 15:44:24 and read 6114 times.

Quoting flyingturtle (Reply 11):
11:59 AM is one minute before noon. So, 12 AM is noon.

I'm afraid not. In the 12-hour system 12 AM always been midnight, definitely not noon. 12 PM is noon.

Topic: RE: 11:59 Pm Vs Midnight Departures, Double Per Diem?
Username: kalvado
Posted 2012-09-04 17:32:11 and read 6080 times.

Quoting CosmicCruiser (Reply 10):
I can't imagine someone booking a flight and not knowing when it departed.

Try to imagine someone booking a flight and knowing when it departs - but knowing incorrectly.

Topic: RE: 11:59 Pm Vs Midnight Departures, Double Per Diem?
Username: CosmicCruiser
Posted 2012-09-04 18:22:15 and read 6059 times.

Your humor did get a chuckle but sorry but it is written in regular am/pm time it takes very little "deciphering" to figure out and "know correctly".  

Topic: RE: 11:59 Pm Vs Midnight Departures, Double Per Diem?
Username: ZSOFN
Posted 2012-09-05 00:25:45 and read 5991 times.

Quoting flyingturtle (Reply 11):
I'll never book a flight to your country, ever again... Wow!

I live in the UK and we use the 24 hour clock - I think you've misinterpreted my response. Regardless moving everyone to a 24-hour clock makes far more sense.

For the record regarding 12am / pm:

http://en.wikipedia.org/wiki/12-hour_clock

Topic: RE: 11:59 Pm Vs Midnight Departures, Double Per Diem?
Username: copter808
Posted 2012-09-05 09:40:48 and read 5885 times.

Quoting CosmicCruiser (Reply 16):
Your humor did get a chuckle but sorry but it is written in regular am/pm time it takes very little "deciphering" to figure out and "know correctly".

But using the 24-hour clock takes even less deciphering!

The incorrect use of AM/PM is common in some areas. If it has to do with store hours, a little common sense will figure it out. Much less clear in airline schedules though.

Topic: RE: 11:59 Pm Vs Midnight Departures, Double Per Diem?
Username: PWMRamper
Posted 2012-09-07 01:12:08 and read 5677 times.

I still don't quite grasp what day an 00:00 flight departs.


I would assume if I booked a flight on October 2nd @ 00:00, I would get to the airport on October 1st @ 22:00 to check in.


Correct?


But to many people, midnight is still the prior day. So I'm sure you'd have plenty of people showing up @ 22:00 on October 2nd.


This is why there are 23:59 departures and 00:01 departures. Makes things much, much easier.

Topic: RE: 11:59 Pm Vs Midnight Departures, Double Per Diem?
Username: flyingturtle
Posted 2012-09-07 05:20:52 and read 5648 times.

Railway timetables sometimes have 24:00 if the last minute of the old day is meant (especially for arrivals), and 0:00 if the first minute of the new day is meant (especially for departures).

But strictly speaking, 24:00 does not exist, because 0:00 already does.

Quoting PWMRamper (Reply 19):
I would assume if I booked a flight on October 2nd @ 00:00, I would get to the airport on October 1st @ 22:00 to check in.

Right, I'd do this too.

Somewhere on this forum, a flight dispatcher wrote that many people showed up a full day late for their flights. Because there were always people doing this, they were simply rebooked to their new flight... and this suddenly stopped when they introduced 23:50 departures.


David

Topic: RE: 11:59 Pm Vs Midnight Departures, Double Per Diem?
Username: TS-IOR
Posted 2012-09-25 08:01:18 and read 4873 times.

This timing is used for passengers to avoid the date of flight confusion that may happens with midnight arrivals or departures.

Topic: RE: 11:59 Pm Vs Midnight Departures, Double Per Diem?
Username: Viscount724
Posted 2012-09-25 19:08:00 and read 4757 times.

Quoting TS-IOR (Reply 21):
This timing is used for passengers to avoid the date of flight confusion that may happens with midnight arrivals or departures.

As far as I know, the OAG system (used by almost all major airlines to distribute schedules to GDS systems) does not permit the use of 2400 as a departure time and 0000 as an arrival time. 2400 could be an arrival time and 0000 could be a departure time but due to the resulting confusion already mentioned, you virtually never see such times in airline schedules. It's much clear when it's 2359 or 0001.

Topic: RE: 11:59 Pm Vs Midnight Departures, Double Per Diem?
Username: COSPN
Posted 2012-09-26 01:30:31 and read 4710 times.

Most people in the USA do not know the 24 Hour clock only Military and Airlines use it..

Topic: RE: 11:59 Pm Vs Midnight Departures, Double Per Diem?
Username: Starlionblue
Posted 2012-09-26 03:23:50 and read 4694 times.

Quoting COSPN (Reply 23):
Most people in the USA do not know the 24 Hour clock only Military and Airlines use it..


Well, all of aviation does. For example all aviation weather products are 24-hour clock and Zulu time.

Topic: RE: 11:59 Pm Vs Midnight Departures, Double Per Diem?
Username: bond007
Posted 2012-09-26 05:54:12 and read 4651 times.

Quoting COSPN (Reply 23):
Most people in the USA do not know the 24 Hour clock only Military and Airlines use it..

Regardless, this issue is not really related to whether we use the 24-hour clock or not, but how we define and understand Midnight.

Quoting PWMRamper (Reply 19):
This is why there are 23:59 departures and 00:01 departures. Makes things much, much easier.

This is the sensible solution to this.


Jimbo


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