Effects of aircraft relative density on spin and recovery characteristics of some current configurations
Year: 1965
Type: article
Abstract: a l study has been conducted on a high-speed d i g i t a l computer u t i l i z i n g six-degree-of-freedom equations of motion t o examine t h e e f f e c t s of r e l a t i v e d e n s i t y on t h e s p i n and recovery c h a r a c t e r i s t i c s of f o u r configurat i o n s which are r e p r e s e n t a t i v e of modern a i r p l a n e s .Two approaches were used: Computations w e r e made simulating conditions f o r which t h e a i r p l a n e obtained a disturbance t h a t put it a t a high angle of a t t a c k with applied r o t a t i o n i n a near-developed s p i n condition a t various i n i t i a l a l t i t u d e s t o determine whether a developed s p i n would ensue.After it w a s determined t h a t developed s p i n s d i d ensue i n t h e first group of calculations, separate c a l c u l a t i o n s were made t o determine whether a s p i n could be entered starting a t o r near trimmed g l i d i n g f l i g h t (1 g s t a l l maneuvers).The r e s u l t s i n d i c a t e t h a t t h e e f f e c t s of changing r e l a t i v e d e n s i t y on developed s p i n s and recoveries were as follows: gave faster r o t a t i n g spins, higher r a t e s of descent, lower values of t h e s p i n c o e f f i c i e n t , l i t t l e change i n angles of a t t a c k and s i d e s l i p , and recoveries, i f obtained, were slower. Changes i n r e l a t i v e d e n s i t y can make t h e d i f f e r e n c e between a s p i n and a no-spin when e n t r y i s attempted by means of a l g s t a l l maneuver, but t h e e f f e c t of r e l a t i v e d e n s i t y i s not c o n s i s t e n t . About t h e only g e n e r a l i z a t i o n t h a t can be made on t h e e f f e c t of r e l a t i v e d e n s i t y on t h e s p i n e n t r y i s t h a t i n c r e a s e s i n r e l a t i v e d e n s i t y cause increased r o l l o s c i l l a t i o n s during t h e spin-entry motions.An increase i n r e l a t i v e d e n s i t y pitching-moment c o e f f i c i e n t , YT
Authors: S. B. Grafton, W. D. Grantham
Institution: Langley Research Center
Language: English
Subfield: Aerospace Engineering
Field: Engineering
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W790458756