Solution’s Advantages and Impact
Weight. The limitations of hydraulics have effectively precluded the introduction of pitch control to large propellers and some very large cooling fans. Hydraulic pitch control requires a pre-existing onboard hydraulic pump with supporting lines, filters, sumps, fittings, etc. that adds to a vehicle’s overall weight. An army ground vehicle’s heavy-duty operation generally requires such a pump be onboard for other applications – in such circumstances, there are still added weight burdens like a very large failure-prevention spring (not needed in EMCP) and the pitch controller’s oil distribution box which facilitates the transfer of hydraulic fluid into the fan’s rotor system (incurring mechanical coupling between the rotating/stator system as well as significant inefficiencies and control non-linearities). For aircraft not typically equipped with hydraulics, EMCP will provide a significant weight savings advantage.