Whist trying to get one of those damn power ball thingies
to work properly, I came up the notion of implantable
gyros.
Put simply, gyroscopes are implanted in two roughly
hemispherical objects, or for the male crew members,
smaller and slightly lower ones.
These are spun up magnetically
before the flight, and then
in the event of instrument failure, a member of flight
crew can be strapped into a gimbal and give some idea of
the correct course inclination/declination etc.
Please no "flying by the seat of the pants" jokes.
In the event of the fly by wire going on the fritz, the entire
flight crew can be spun up and steer the plane in lieu of
the control surfaces.
The spin-off applications for exotic dancers of whatever
persuasion are entirely predictable.