Investigation into excessive pantograph trajectory amplitudes observed on MK IIIA equipment in high winds (TN-DA-032)

Excessive pantograph trajectory amplitudes have been experienced during Mentor line-proving runs on Mk IIIA overhead equipment in high winds. This report demonstrates that the observed behaviour can be explained by a combination of the following : 1. aerodynamic forces on the overhead, causing loss of sag; 2. aerodynamic...