A Theoretical Investigation of the Effect of Partial Wing Lift on Hydrodynamic Landing Characteristics of V-Bottom Seaplanes in Step Impacts
Abstract
A theoretical investigation is made of the motions and hydrodynamic loads experienced during the impact of prismatic V-bottom seaplanes in the step-landing condition where the wing lift is a constant fraction of the weight and the resultant velocity is normal to the keel. An approximate method is given for applying the results of this investigation to the more general case of oblique impact. This method involves obtaining an equivalent normal impact for any given oblique impact and then assuming that the percentage change in load due to a change in wing lift is the same in both oblique and normal impacts. Equations are presented which relate the load and motion variables throughout a normal impact and it is shown that these variables may be expressed as dimensionless quantities which are related by a single parameter lambda. This parameter depends on the unbalanced wing lift force, the initial conditions of the impact, and the hydrodynamic characteristics of the seaplane. The results of the investigation are presented in the form of dimensionless plots which may be used directly to determine the loads, motions, and hydrodynamic pitching moments at any instant of the impact. These results suggest that the increase of hydrodynamic load is approximately 133 percent of the decrease in air load.
Document Details
- Document Type
- Technical Report
- Publication Date
- Nov 01, 1952
- Accession Number
- ADA377047
Entities
People
- Emanuel Schnitzer
- Joseph L. Sims
Organizations
- National Aeronautics and Space Administration