Preliminary Investigation of Self-excited Vibrations of Single Planing Surfaces

Preliminary Investigation of Self-excited Vibrations of Single Planing Surfaces
Author: Elmo J. Mottard
Publisher:
Total Pages: 26
Release: 1956
Genre: Planing hulls
ISBN:

A preliminary investigation was made of self-excited vibrations of single planing surfaces. A self-excited oscillation requiring freedom in rise but not in trim occurred with high aspect ratio (order of 10) of the wetted portion. This vibration could be controlled most successfully by methods (such as the use of dead rise) which limited the wetted aspect ratio.

Annual Report

Annual Report
Author: United States. National Advisory Committee for Aeronautics
Publisher:
Total Pages: 534
Release: 1953
Genre: Aeronautics
ISBN:

Analysis and Comparison with Theory of Flow-field Measurements Near a Lifting Rotor in the Langley Full-scale Tunnel

Analysis and Comparison with Theory of Flow-field Measurements Near a Lifting Rotor in the Langley Full-scale Tunnel
Author: Harry H. Heyson
Publisher:
Total Pages: 696
Release: 1956
Genre: Air flow
ISBN:

Results of an investigation in the Langley full-scale tunnel of the induced flow near a lifting rotor are given. Measurements of stream angles and velocities were made in several transverse planes along and behind the rotor in four different conditions representative of the cruising and high-speed ranges of flight. These measurements indicate that available theory may be used to calculate with reasonable accuracy the induced flow over the forward three-quarters of the disk for these flight conditions provided that a realistic nonuniform rotor disk-load distribution is assumed. Rearward of the three-quarter-diameter point, calculations of the induced velocity are increasingly inaccurate due to the rolling up of the trailing-vortex system. Farther rearward, well behind the rotor, the flow may be represented more accurately by the flow behind a uniformly loaded wing.

Report

Report
Author:
Publisher:
Total Pages: 524
Release: 1953
Genre: Aeronautics
ISBN: