To Brian:
Thule is exactly the type of VOR i'm referring to. And for your info Thule has been true-north oriented for at least couple of years.
cribble:
thanks. i'm well aware of that the 777 has the push-button for switching all the reference on the navigation system to true headings/tracks, right in front of the captains seat. but the complications of true north oriented VORs is more than that..
i should clarify the scenario:
let's say the ND is in map mode and heading reference is "NORMAL" (mag north oriented), and you fly by Thule (THT) VOR which is true north oriented.
question now is:
how is the VOR needle displayed on the ND?
is it displaying the raw data from the VOR (which would results in a mismatch between the needle direction and the VOR position on the ND)?
or does the navigation database knows that Thule is true north oriented and the picture is corrected for that (i.e. wrong raw data information is displayed if you try to read the numbers under the VOR needle but a directionally correct needle on the ND)?
it's pure technical interest coz it's all GPS primary these days, but on this topic... how will the 777 FM response to that? will it attempt to do a position update from true north VORs (not knowing it is true north oriented?), which would then result in a grossly incorrect position update?
(to those who haven't flown the long range version of the Airbuses...the navigation database on the airbus can distiguish between true north and mag north VORs. and the display on the ND are always corrected for that, no matter it's a mag north VOR on a true north display or the vice versa.)
maybe the Continental guys will know about this.
