Comparison of Model and Full-Scale Spin Test Results for 60 Airplane Designs
Abstract
The results of Langley spin-tunnel investigations have been compared with corresponding full-scale results available for 60 different airplane designs. The purpose of the comparison was to determine the reliability of the model results in predicting full-scale spin and recovery characteristics. Analysis of the data showed that model tests satisfactorily predicted full-scale recovery characteristics approximately 90 percent of the time. For the remaining 10 percent of the time, the model results were of value in predicting some of the details of the full-scale spins. Generally, when the models spun at angles of attack less than 45 deg, the corresponding airplanes spun at larger angles of attack; and when the models spun at angles of attack greater than 45 deg, the corresponding airplanes spun at smaller angles of attack. When the tail-damping ratio was greater than 0.02, the models spun with higher rates of rotation than the airplane; and when it was less than 0.02, the models spun with lower rates of rotation. Generally, the models spun with less altitude loss per revolution than the corresponding airplanes, but a higher rate of descent was found to be associated with the smaller angle of attack, whether of airplane or model. The airplanes generally spun with the inner wing down more than the inner wing of the corresponding models. Predictions of emergency-recovery- parachute sizes based on model results were found to be somewhat conservative.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jul 01, 1950
- Accession Number
- ADA380574
Entities
People
- Theodore Berman
Organizations
- National Aeronautics and Space Administration