28th Jan 2002, 04:52
I don't if this subject's been discussed already and sorry if it has.. .Can anyone tell me why and when do crewmembers use the Route Offset option, which is present on some FMC (the 747 for example).
Thank you.. .Campos.
28th Jan 2002, 14:12
Indeed it has been discussed. Use the search facility. Also I think there is something on Tech/Safety or one of those options down the left side of the screen.
29th Jan 2002, 05:26
Can be used for standard offsets with an engine failure on an oceanic route, or for a constructed offset around weather.
29th Jan 2002, 06:02
Thanks for the replies!!
30th Jan 2002, 01:35
If Atc require you to slow down and lose time at high altitude in the cruise and you are already at LRC speed and you are disinclined to slow further as you could not regain your cruise speed in level flight, you could achieve a 5 mile left offset, followed by 5 mile right offset, (with Atc approval) to effectively tack to lose the required time to cross the active way point at the time specified by the Atc.
30th Jan 2002, 12:32
When flying down through certain parts of Africa, it is advised to Fly a 1 NM off-set when within the IATA In-flight Broadcast Area.
30th Jan 2002, 16:31
i think it's high time we come out with a standard offset (either left or right) when flying within IFBA.
our company had a proximity traffic climbing thru their level few months ago. though the TCAS might have saved the day but it wouldn't be too healthy to the heart if it happens once too often.
31st Jan 2002, 14:02
In my company we also use the route offset as a guide for weather diversion.
eg. We are cleared up to 20 miles left of track, so we enter L20 (left 20nm) in the route page, and DONT execute it. This produces a white dotted line 20nm left of track.
ODL <img src="smile.gif" border="0">
31st Jan 2002, 15:00
I know that the offset is also used by ATC instructing acft to offset by 5nm to enable an opposite direction climb or descend through. It saves locking acft on headings and uses minimal airspace to achieve exactly 5 nm. I'm old fashioned and prefer acft locked on headings.
31st Jan 2002, 18:30
In NAT-RVSM airspace, I believe you're authorized to fly a 1 or 2 mile offset, if you're encountering wake turbulence from the sircraft in front of you.