Accurate Timepiece
Join Date: Feb 2006
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As long as the GPS device displays the time in seconds, then it would comply. In theory it will be more accurate than a digital watch as it's running directly off GMT and updated frequently via the satellites.
The GPS clock does operate but if the signal loss is at power up it may just indicate the last shut down time, that is it needs the satellite to update the clock as well. I have noticed this on some GPS units, they will start counting from the previous shut down time until satellites aquired.
The watch issue will depend on the category of operation. If its a charter or RPT than a clock fitted to the aircraft is required, whether the pilot caries one does not matter. However if the clock in the aircraft does fail then it would be up to the MEL whether or not you could use the GPS clock etc...
The watch issue will depend on the category of operation. If its a charter or RPT than a clock fitted to the aircraft is required, whether the pilot caries one does not matter. However if the clock in the aircraft does fail then it would be up to the MEL whether or not you could use the GPS clock etc...
In theory it will be more accurate than a digital watch as it's running directly off GMT and updated frequently via the satellites.
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Join Date: May 2009
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Thanks guys,
Was just curious as it was indicated to me that it was sufficient.
Although not very useful for RNAV holding pattern timing
(depending on the actual unit)
Cheers
Was just curious as it was indicated to me that it was sufficient.
Although not very useful for RNAV holding pattern timing
(depending on the actual unit)Cheers
Join Date: Aug 2003
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My understanding is that they run off Atomic clocks. Additionally, every few years as the earth slows in its rotation, there is a leap second inserted at year's end. The GPS clocks do NOT account for this, and consequently the GPS time is now ahead of GMT by a few seconds (I have lost track of exactly how many).
The GPS Time is corrected back to UTC so you don't have to worry about the correction factor unless you download the raw GPS data.
In which case you'll first have to do some math because it's reported in seconds elapsed after midnight 5th jan 1980 plus the accumulated leap seconds.
The requirement was for an accurate timepiece with a sweep second hand, making digital clocks unacceptable. The requirement may have changed but I'm not interested enough to look right now.
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Checking CASA, it states "an accurate timepiece indicating hours, minutes and seconds" It no longer indicates analogue or digital.
With regards to synchronizing watches regularly:
If you own a PC with either Win-XP or Vista and are also on the internet, you can double-click the time in the bottom right of the screen, then click on "Internet Time". This will display the options for synchronizing your PC with an insanely accurate Time Keeping Server online. Once you've synced your PC, you can sync your watch with it to the second! No more calls to telstra!
With regards to synchronizing watches regularly:
If you own a PC with either Win-XP or Vista and are also on the internet, you can double-click the time in the bottom right of the screen, then click on "Internet Time". This will display the options for synchronizing your PC with an insanely accurate Time Keeping Server online. Once you've synced your PC, you can sync your watch with it to the second! No more calls to telstra!
Last edited by Jazzy78910; 4th May 2009 at 09:54.
Bugsmasherdriverandjediknite
Join Date: Jul 2000
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Hell, if my $3 sevo watch is in the same hour, I'm happy. I can't count anyway, so I guess at ETA, circuit at time. 
Geeeeez what is it with you technology freaks.
I've had my old watch for years and it was just fine for use when I was flying.
Bloody young whippersnappers!
Here's mine.
I've had my old watch for years and it was just fine for use when I was flying.
Bloody young whippersnappers!
Here's mine.
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Pete... does that thing work when in IMC? or at night?
My understanding is that GPS, for every second of error from the satellites equates to about 200nm error on the ground/in the air.
11% .... where are you????????????
besides..... "accurate timepiece displaying hours,minutes AND seconds is a tax deduction EVERY YEAR!!!! just call it a"NDB timer", not a watch, and there are no problems!.... besides... you ONLY need a receipt IF you get audited, or it costs more than xxx dollars!
My understanding is that GPS, for every second of error from the satellites equates to about 200nm error on the ground/in the air.
11% .... where are you????????????
besides..... "accurate timepiece displaying hours,minutes AND seconds is a tax deduction EVERY YEAR!!!! just call it a"NDB timer", not a watch, and there are no problems!.... besides... you ONLY need a receipt IF you get audited, or it costs more than xxx dollars!