Transport Research International Documentation (TRID) https://trid.trb.org/ en-us Copyright © 2026. National Academy of Sciences. All rights reserved. http://blogs.law.harvard.edu/tech/rss tris-trb@nas.edu (Bill McLeod) tris-trb@nas.edu (Bill McLeod) Transport Research International Documentation (TRID) https://trid.trb.org/Images/PageHeader-wTitle.jpg https://trid.trb.org/ A SELF-PITCHING PROPELLER https://trid.trb.org/View/396743 Thu, 21 Jul 1994 00:00:00 GMT https://trid.trb.org/View/396743 WORLD'S FIRST SELF-PITCHING PROPELLER https://trid.trb.org/View/396769 Thu, 21 Jul 1994 00:00:00 GMT https://trid.trb.org/View/396769 SELF-PITCHING PROPELLER TRIALS PROVE BENEFITS https://trid.trb.org/View/401320 Thu, 21 Jul 1994 00:00:00 GMT https://trid.trb.org/View/401320