The influence of rolling moments on spin recovery as observed in model-spinning tests

Abstract

Several aspects of model-spinning test technique have been brought into prominence by recent full-cale developments. Correlation between model and full-scale recoveries has been poor in some cases, and it appears from model tests of some new aircraft that full-scale recovery may depend on other means in addition to the normal use of rudder and elevator. Analysis of model data shows the effects of applied rolling moments and of aileron deflections on both spin and recovery to be closely related to the distribution of loading in the aircraft. The ordinary model-test result can be considerably in error in either direction due to the neglect of probable scale effects on rolling moments. Deflection of the ailerons can be of great assistance to model recovery and flight confirmation of this effect is required. Information on the scale effects on rolling moments for delta aircraft is also urgently needed, as these models show much greater sensitivity than conventional models to the application of rolling moments.