As someone interested in aviation (and flight simulation), I can answer this:
No, modern jet airliners do not depend on magnetic compasses, but rather have at least 2 Inertial Navigation Systems.
Inertial Navigation Systems find true north by detecting the earth's rotation during an alignment phase (while the aircraft is still stationary). They contain 3 axes of gyros (usually laser-ring gyros) and 3 axes of accelerometers. Using these, after alignment, they keep track of their current orientation and position.
Many airliners do have a magnetic compass as a backup -- but they're inaccurate if you are turning, accelerating, or changing altitude (not sure on the last one).
Other sensors, however, may internally use magnets. Also, a minibot could latch itself onto the aircraft's frame...
Of course, the only things that matter here are the regulations, but I just had to say this
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I hope your minibot makes it safely to your regional.
EDIT: Forgot to mention that since aviation still uses magnetic direction (that is how runways are numbered, and what any aircraft smaller than a jet airliner would use (an aviation-grade INS is probably way more expensive than a Cessna)), the Flight Management System has to use a database of magnetic variations to convert true north back into magnetic north. On at least some planes (the MD-11 at a minimum), the pilot has a switch for true/magnetic headings.
EDIT2: I should have known better. Aluminum isn't magnetic. Thanks to jgw for pointing that out. The minibot couldn't latch onto the aircraft's frame.