From Chris Duif, Delft University of Technology
Peter Grant raises the question of whether gyroscopic navigation systems would register the reported anomalous effects observed in pendulums during a solar eclipse (25 December 2004, p 30). This is currently under study. It depends on what kind of interaction, if any, causes the deviations. If it is a tilt or horizontal force component, it is unlikely that this will be detected on board an aeroplane. If it is a rotational force, it might be detectable in principle.
Any disturbances would be small, though. You need a laboratory in a quiet site to perform reliable measurements.
Delft, The Netherlands
