The NACA CYH Airfoil Section

The NACA CYH airfoil section is described and its aerodynamic characteristics are given as tested in the NACA variable density wind tunnel at twenty atmosphere pressure. This section has a low drag, a high maximum lift, and a small travel of center of pressure

A study of the pitching moments and the stability characteristics of monoplanes

This note presents a study of the pitching moments and the stability characteristics of monoplanes. Expressions for the pitching-moment coefficient and the Diehl stability coefficient for the monoplane are developed, suitable for the use of airplane designers. The effective difference between the high-wing and low-wing types is portrayed and discussed. Comparisons between experimental and computed values are made. Charts for use in the solution of numerical values of the pitching-moment and stability coefficients are presented

Whirl and Stall Flutter Simulation Using CFD

This paper presents recent research on numerical methods for whirl and stall flutter using computational fluid dynamics. The method involves coupling of the HMB3 CFD solver of the University of Glasgow and a NASTRAN derived structural model. Based upon a literature survey, a significant amount of research has been conducted on the numerical investigation of tiltrotors, with a focus on the XV-15 and V-22 aircraft. Within this paper, the coupling procedure is presented along with a steady CFD computation to highlight the accuracy of the high-fidelity method. In addition to this, a simple method is used to investigate the whirl flutter boundary of a standard propeller and the XV-15 blade

Physical Development of Photographic Plates

Physical development of photographic plates is not as efficient as chemical development. While it produces very fine grain negatives, longer exposure than normal is required and plates must be developed an hour to produce satisfactory printing densities. pH of the developer is important

Fine Grain Photographic Development

The effect of different fine grain photographic developers upon the effective emulsion speed and grainines of photographic materials was studied quantitively. Fine grain developers were found to be more effective in reducing the graininess of fast coarse grain emulsions than of slow fine grain emulsions. The effective emulsion speed of slow fine grain emulsions when developed in a MQ Borax developer was found to be at least equal to that of a fast coarse grain emulsion when developed in an ultra fine grain developer which gave negatives of as low graininess on the fast emulsion as the .i\IQ Borax gave on the slow emulsion. Slight improvement in graininess can be obtained by using ultra fine grain developers on fine grain emulsions, but only at some sacrifice of effective emulsion speed

Grade placement of units in general science.

Thesis (M.S.

Photomicrographs of Snow Crystals

This paper discusses techniques which have been developed for obtaining photomicrographs of snow crystals

Professor Richardson et al.: A New England Education

George V. Higgins contributes to the series on the New England state of mind, identifying a New England code of acceptable behavior whose hallmarks are discretion and a sense of decency, still powerful enough to prompt even those flouting it, and getting caught, to feel a sense of guilt

Fine grain photographic development

The effect of different fine grain photographic developers upon the effective emulsion speed and grainines of photographic materials was studied quantitively. Fine grain developers were found to be more effective in reducing the graininess of fast coarse grain emulsions than of slow fine grain emulsions. The effective emulsion speed of slow fine grain emulsions when developed in a MQ Borax developer was found to be at least equal to that of a fast coarse grain emulsion when developed in an ultra fine grain developer which gave negatives of as low graininess on the fast emulsion as the .i\IQ Borax gave on the slow emulsion. Slight improvement in graininess can be obtained by using ultra fine grain developers on fine grain emulsions, but only at some sacrifice of effective emulsion speed