[time-nuts] Aircraft ping timing

iovane at inwind.it iovane at inwind.it
Thu Mar 20 01:24:14 UTC 2014


>----Messaggio originale----
>Da: jfor at quikus.com
>Data: 20/03/2014 1.47
>
>It depends on how accurately the bird can measure the round-trip time:
>
>1 us  = ca 500'
>10 us = ca 1 mile
>100us = ca 10 miles
>1 ms  = ca 100 miles
>
>The arcs are loci of constant round trip time, projected on the globe.

This is valid for round trip and for the signal path which in this case is the 
line generating the cone having the bird at its apex. The radius of the circle 
at earth is another thing, and the error should be multiplied by some factor 
which depends on the angle at the apex, being the earth's surface curve. Hence 
I tought that the timing is crucial. Add to this that I understood it was not a 
ping as we usually mean, but a one way signal (aircraft to satellite). Hence my 
question.

Antonio I8IOV
>
>-John
>
>===============
>
>
>
>
>> My question was on what would be the expected accuracy of the circle's
>> radius.
>>
>> Antonio I8IOV
>>
>>>----Messaggio originale----
>>>Da: bill at iaxs.net
>>>Data: 20/03/2014 1.21
>>>
>>>They only got one ping from INMARSAT at 64E above the Indian Ocean.
>>>There was no other ping to triangulate the position.
>>>
>>>One ping projects a circle on the Earth. The maximum flying range of the
>>>plane determined the ends of the NE and SE arcs of that circle.
>>>
>>>The news only gets stranger as time goes on.
>>>
>>>Bill Hawkins
>>>
>>>
>>>-----Original Message-----
>>>From: iovane at inwind.it
>>>Sent: Wednesday, March 19, 2014 6:46 PM
>>>
>>>Those who say the missing aircraft should be searched along the two
>>>corridors, what measurement are they relying on? I think it is a one-way
>>>measurement of time-stamped pings, which implies good synchronization of
>>>clocks between a geosynchronous satellite and a moving aircraft. Antonio
>>>I8IOV
>>>
>>>
>>
>>
>> _______________________________________________
>> time-nuts mailing list -- time-nuts at febo.com
>> To unsubscribe, go to
>> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
>> and follow the instructions there.
>>
>>
>
>
>





More information about the Time-nuts_lists.febo.com mailing list