Roy Smith wrote:
I've got AC 43.13-1B, which describes the procedure to swing a compass.
What I can't find is the bureaucratic stuff -- who can do it (any pilot?),
and what paperwork follow-up is required (airframe logbook entry, or is
just making the new compass card sufficient?).


Recently the compass rose has come up office conversation and who,
when, how, and what type of compass survey should be accomplished. I
can assure everyone reading this not all airport have a surveyed
compass rose (calibrated). Many airports have compass roses that may
not be accurate due to underground pipes or other metal objects that
will affect the accuracy of the survey.

The FAA has published a document FAA No. 405, Standards for
Aeronautical Surveys and Related Products that explains why and how a
compass rose should be surveyed.

Next who can perform the calibration to your onboard compass installed
in your aircraft? Only a Repair station with the proper ratings with
the proper training, current manuals available, and proper tooling.
This is where it may get sticky for some. FAR 65 Subpart D for
Mechanics does NOT allow Airframe rated mechanic to calibrate
compasses. Only a repair station with the proper rating can perform
this task. FAR 65.81(a) excluded airframe mechanics form performing
maintenance, major repairs to, and major alterations of, propellers,
and any repair to, or alterations of instruments. FAR 1.1 under
maintenance explains calibrations are considered a repair. So this
just leaves repair stations to adjust your compass.

Needless to say a pilot cannot perform this task as it is not
considered preventive maintenance.

AC 43.13-1B does explain how to perform a compass swing and is
acceptable data however the compass rose has to be surveyed to make it
legal. The repair station will make an airframe record entry stated
what data the followed such as AC 43.13-1B, chapter 1, section 3. FAR
23.1327 explain the installed compass has to be accurate and all
compasses are classified as instruments.

Bottom line is the compass rose has to be surveyed (check with your
local airport) and a repair station has to perform the compass swing
and make a airframe record entry.

Stache