Hartzell Overhaul Instructions # 108A isFAA Approved and covers 3 Blade Constant Speed Feathering Propeller model HC-B3Z30-2E. is illustrated and Approved arch 10,1967. Hartzell Blade Angle chart dated May 1, 1972 has 6 pages. The Hartzell Blade Repair Tolerance Specifications has 4 pages.