Adjustable blade load mechanism for wiper arm assembly

A windshield wiper system for an aircraft comprising:

• a wiper drive shaft comprising:
• a first end of the wiper drive shaft;
• a second end opposite the first end and spaced axially from the first end relative to a center axis of the wiper drive shaft, the second end comprising:
• a first threaded section between the first end and the second end;
• a second threaded section axially between the first threaded section and the second end;
• and
• a spline section between the first threaded section and the second threaded section, wherein the spline section comprises:
• a plurality of splines extending axially along the wiper drive shaft relative to the center axis of the wiper drive shaft;
• a first stop face at a first end of the plurality of splines and oriented perpendicular to the center axis of the wiper drive shaft;
• and
• a second stop face at a second end of the plurality of splines and oriented perpendicular to the center axis of the wiper drive shaft;
• a first nut configured to thread to the first threaded section and comprising a first stop shelf configured to contact the first stop face;
• a second nut configured to thread to the second threaded section and comprising a second stop shelf configured to contact the second stop face;
• and
• a wiper arm assembly comprising:
• an adjustment sleeve configured to contact the plurality of splines;
• and
• a wiper arm with a first end configured to enclose the adjustment sleeve;
• a second end of the wiper arm attached to a wiper blade.