Re:Plans to shift aviation from magnetic navigation to true ...
by ah88 on Tuesday October 26, 2021 @10:10AM
(#29000616)
CFI here. It’s not a big deal in most of the country but the Pacific Northwest does have variation of about 20 degrees. It can make a difference when calculating takeoff and landing data as winds are true but runways are magnetic.
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Re:Plans to shift aviation from magnetic navigation to true ...
by bronco21016 on Tuesday October 26, 2021 @10:18AM
(#29000707)
I think it’s important to point out the nuance. Observational winds (eg METAR) are recorded in true. Reported winds (ATIS, ASOS, AWOS) are given in magnetic. [1]
The adage goes “If you read it, it’s true. If you heard it, it’s magnetic.”
[1] https://www.faa.gov/documentLibrary/media/Order/7900_5D.pdf Chapter 7.4
Re:Plans to shift aviation from magnetic navigation to true ...
by barbazoo on Tuesday October 26, 2021 @12:01PM
(#29002065)
What if you read the ATIS though? /s
Re:Plans to shift aviation from magnetic navigation to true ...
by maxcan on Tuesday October 26, 2021 @03:11PM
(#29004867)
one of my favorite apocryphal exchanges:
airplane inbound to land: "KXYZ tower, N12345 at 3000' tower: "N12345, KXYZ tower, confirm you have Romeo" airplane: "KXYZ tower, N12345 has Romeo" tower: "N12345, fine, but bravo is current, recommend you recheck atis"
Re:Plans to shift aviation from magnetic navigation to true ...
by bronco21016 on Tuesday October 26, 2021 @04:49PM
(#29006077)
Oh you must have meant KDTW.
Re:Plans to shift aviation from magnetic navigation to true ...
by sheepybloke on Tuesday October 26, 2021 @12:36PM
(#29002555)
When I was working on FMS, that's what we used to test our true north to mag conversions. Just fly across the Pacific Northwest and toggle the switch to verify that everything looks good.