Page:CAB Accident Report, United Airlines Flight 21.pdf/48

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The rotating cam setting for the left propeller was in low pitch of 18 degrees and the blades were at the same pitch. The No. 1 and No. 2 blades were not noticeably bent not the segment gears broken. The blade surfaces were in good condition, showing no scratches and few nicks except one large nick at the tip of the No. 2 blade. The No. 3 blade was bent backward at the 27-inch radius about 30 degrees with the surface in good condition and the segment gear not broken. The shimplates of all three blades showed compression and small cracks.

The rotating cam setting for the right propeller was found at 24 degrees with the No. 1 blade in a feathering position, the No. 2 blade at 25 degrees. The No. 1 blade was bent forward at the 30-inch radius at an angle of approximately 30 degrees with the surface bearing numerous scratches and the entering edge badly nicked. The segment gear was cracked between the No. 4 and No. 5 and between the No. 5 and No. 6 teeth with the No. 7 tooth partially broken off and the segment split and spread. The No. 2 blade was bent back at the 30-inch radius at an angle of 15 degrees with the blade surface and the segment gear in good condition. The No. 3 blade contained a large nick at the tip and was bent slightly forward at the 42-inch radius and the segment gear was in good condition. The shimplates of all three blades showed compression and small nicks.

The examination of the propellers showed that they were rotating at the time of impact. However, it is not possible to state definitely whether they were absorbing power at the time of the impact or whether they were wind-milling without application of power.