_:ndcdc234b2e3b4123bd68465c5689dbf5xb0
<http://schema.org/description>
"The type testing of the Aero products Model A422-69 propeller, intended for use on the T-28 type aircraft, is described. The testing included complete calibration, endurance, and over speed running on the electric motor whril rig, plus endurance running and control operation on the R-l3OO-l engine. As a result of the testing, two changes were made in the propeller a change of the control ring material to a nitriding steel, and an increased diameter of the control ring guide pin. It is concluded from this testing that the Aero products A422-E1 propeller is satisfactory for use on the T-28 aircraft in combination with the R-l3OO-l engine."
<https://apps.dtic.mil/sti/citations/AD0007224>