Apologies for the Misunderstanding

[Harold Rutila]

I received a fair number of complaints regarding my ARTCC's "lack of staffing" of the Aspen Feature Night this weekend. I feel an explanation is due to pilots who tried to fly into KASE with Denver ARTCC ATC.

1.) The Aspen Feature Night was to take place on Saturday at 1800 MDT as advertised on our banner for the event. Here is a link to the actual calendar entry: http://forum.vatusa.net/index.php?act=cale...mp;event_id=608. Unfortunately for those who did not understand this, the VATUSA Events Calendar runs in Zulu time. 1800 MDT is also 0000Z, which put our event IN ZULU TIME on October 17th. The local time date was still October 16th.

2.) We fully staffed both Denver International Airport (KDEN) and Aspen Pitkin County Airport (KASE) on the advertised local event time of Saturday, October 16th, 2010 at 1800 MDT. All personnel remained online well past the advertised event end time.

3.) We regret the mis-communication and have worked out a solution for all future events with the same start date. Events that start at this time will now be displayed with a start time of 2359Z to allow the Zulu date and MDT date to correspond.

Thanks.

[Ben Kimball]

I don't think I can even count the number of times I've seen events advertised incorrectly; yours was done correctly, which is probably what caused the confusion!  I think a good rule of thumb for ECs out there would be: *never* start an event at 0000Z. I like your 2359 solution.

Cheers,
Ben

[Lloyd Boyette]

I don't think I can even count the number of times I've seen events advertised incorrectly; yours was done correctly, which is probably what caused the confusion!  I think a good rule of thumb for ECs out there would be: *never* start an event at 0000Z. I like your 2359 solution.

Cheers,
Ben

Actually, the event was posted incorrectly. The only place in the world that the day would change at 0000z is at the dateline. So, if you were standing in London, Dublin, Edinburgh, Lisbon, Reykjavik or Casablanca then yes.... 0000z would turn the date to the 17th and 2359z would still keep you on the 16th. However, if you were to stand in Colorado at 0000z ( GMT -6 ) then the current date and time would still be 1800MDT on the 16th of the month. The only confusion is people think that 0000z magically turns the date to the next day everywhere in the world.... which it doesn't.

If you were to post your event at 0000z on the 16th of the month pilots would know to be there at 1800MDT on the 16th of the month... because it's in Colorado, and thanks to the conversion process. It is absolutely correct to say 0000z on the 16th. 2359z has absolutely no effect on what day it is... that just makes it 1759MDT on the same day ( Unless you're standing in London ). Truthfully... all the other ECs know this and that's why we never have issues posting events on the VATUSA Calendar.  

Hope this helps.
Lloyd O Boyette | EC/MTR

[Daniel Hawton]

Actually, the event was posted incorrectly. The only place in the world that the day would change at 0000z is at the dateline. So, if you were standing in London, Dublin, Edinburgh, Lisbon, Reykjavik or Casablanca then yes.... 0000z would turn the date to the 17th and 2359z would still keep you on the 16th. However, if you were to stand in Colorado at 0000z ( GMT -6 ) then the current date and time would still be 1800MDT on the 16th of the month. The only confusion is people think that 0000z magically turns the date to the next day everywhere in the world.... which it doesn't.

If you were to post your event at 0000z on the 16th of the month pilots would know to be there at 1800MDT on the 16th of the month... because it's in Colorado, and thanks to the conversion process. It is absolutely correct to say 0000z on the 16th. 2359z has absolutely no effect on what day it is... that just makes it 1759MDT on the same day ( Unless you're standing in London ). Truthfully... all the other ECs know this and that's why we never have issues posting events on the VATUSA Calendar.  

Hope this helps.
Lloyd O Boyette | EC/MTR

That is not correct.  Zulu is its own time zone, essentially.  Once it hits 0000z, no matter where you are standing, as long as you refer to zulu time you also refer to the zulu date.  As real world ATC, I can attest that this is how zulu time is used for aviation.  It's also same with time zones.  Just because you are standing in mountain, when eastern time zone hits midnight, and you refer to the eastern time, you also are referring to the eastern date.

Thus:

Saturday, 16 October, 10:00PM Mountain
Sunday, 17 October, 12:00AM Eastern
Sunday, 17 October, 4:00AM GMT/Zulu
^ Refer to the same point in time.

So, if you refer to 0400Z and mean 2200 Mountain, you would say 17 October, 2010 at 0400z.  When you convert it to Eastern, you subtract 4 hours.. which moves it to 17 October, 2010 at 0000L.  When you move it to mountain, you subtract a total of 6 hours, since it moves it past midnight you subtract a day... thus 0400z 17 October 2010 becomes 2200L 16 October 2010.

Here's a tool that will do it for you. http://www.timezoneconverter.com/cgi-bin/tzc.tzc

[Harold Rutila]

Lloyd,

The answer above is exactly what I've been trying to explain in the staff forum. You can't run dates in local with inserted times in Zulu without affecting the local date in the time conversion for events on 0000Z.

[Lloyd Boyette]

.