While reviewing below arducopter wikis, I have a question to community:
will using mumetal (magentic shielding) make the copter more compact and compass safe?. will this help in reducing the distance between APM/PixHawk and the battery. Also, can external GPS mast be avoided by using mumetal?.
References:
http://diydrones.com/profiles/blogs/mumetal-testing
https://youtu.be/bOf6zfDSO6E
http://ardupilot.org/copter/docs/common-magnetic-interference.html#common-magnetic-interference
http://ardupilot.org/copter/docs/common-compass-calibration-in-mission-planner.html