Need some good user input...
Looking for folks who operate off oil platforms or in the Canadian North.
Question is whether you still actively use "DG" (unslaved mode) for your compass system. Given GPS would you miss it if it were not there? (i.e. mag slaved mode only)
I've been told that folks flying to oil platforms switch to DG mode when they get close to the platform (because all that iron affects the compass). Is that true? How close do you switch?
I've also been to told guys in the Canadian north use DG mode (because of proximity of the pole makes mag slaving unworkable), and instead set the DG based on ground reference or GPS track.
The issue is that there is new technology coming into vogue that is destined to replace the old gyro systems, This technology has allowed fixed-wing aircraft to now be offered with really cheap glass cockpits. A key ingredient of the cheap system is an attitude and heading sensor that uses MEMS technology (micro electro-mechanical sensors), but the problem is that these "gyros" don't remain stable very long when they lose their slaving. As a result, most of the fixed-wing systems using this technology no longer provide a "DG" mode. Question is whether losing the DG mode is acceptable for helicopters.
I've been told that people have worked around this by flying GPS track, and that the new magnetometers are less affected by declination angle and so you don't get the attitude based compass errror in the far north like you got with the old systems.
Other people have told me that it's only the old farts who still use DG mode.
The guys flying CAPSTONE stuff in Alaska may have some opinion on this as well. Since the technology was developed for the CAPSTONE program, but is now being used in stuff like Garmin G-1000, Honeywell APEX-2000, Chelton Flight sytems, and the system on the new Eclipse (Avidyne). Given the cost and reliability of the MEMS, it will eventually displace traditional compass systems.
---- so the change is coming... is it going to be a problem???
Thanks in advance
Avnx EO