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Leap second

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Author Post
Registered: Jan 2013
Posts: 318
Location: YSSY
Hi all,

so what's going to happen in PSX in 10h when it's 2015 JUNE 30 23:59:60 UTC?

Will the FMCs yield for one second, or will they just tick over as normal and then be one second fast?

What about in the real aircraft? Is there an IERSA table in the FMC that's kept up to date in the FMCs by maintenance (like in our telescopes)?


- Balt
Registered: May 2009
Posts: 5140
Hi Balt,

PSX's clocks will not pause, they will keep accumulating their milliseconds.

To get the real-world UTC after this event, just click on the "Copy real-world UTC to simulated UTC" button on PSX's Time page, provided the computer's system time and calendar has the correct time.

If the computer's system time really freezes for a second, PSX will freeze as well. But I can't imagine that the computer will do this. I guess the effect is implemented in the calendar.


Registered: Jan 2013
Posts: 318
Location: YSSY
Hi Hardy,

there may be no display of the UTC time with a second display in the CDU, but if you're going to arrive at a WPT at 00:00:00 UT on June 30, the ND will falsely display 00:00 for the ETA, not 23:59.9.

If that's your calculated ETA for eg a transatlantic flight, you might in fact be showing the wrong arrival date.


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