INTRODUCTION T h e NASA L a n g l e y R e s e a r c h C e n t e r
has
investigated
the
u s e o f a d e c o u p l e r p y l o n as a means o f s u p p r e s s i n g w i n g / s t o r e flutter
( R e f e r e n c e s 1 t h r o u g h 6).
The c o n c e p t c o n s i s t s o f
reducing t h e pylon p i t c h s t i f f n e s s u n t i l t h e store/pylon pitch
frequency
is less t h a n
the
f u n d a m e n t a l wing
bending
tests have been e x p a n d e d to i n c l u d e t h e f a b r i c a t i o n o f a s h i p s e t o f p y l o n s These pylons w i l l be used t o demonstrate t h e f o r t h e F-16. The c a p a b i l i t i e s o f t h e c o n c e p t w i t h a f l i g h t t e s t program. p y l o n s a r e d e s i g n e d t o replace t h e F-16 p r o d u c t i o n weapon p y l o n s which are c a r r i e d a t S t a t i o n s 3 a n d 7 ( S p a n S t a t i o n frequency.
120).
These
s t u d i e s and wind
The d e t a i l s o f
supporting analysis
tunnel
t h e decoupler pylon design and t h e
are d e s c r i b e d
in
Reference
7
t o which
t h i s document is a n addendum. T h e p y l o n s h a v e a beam p i t c h s p r i n g w h i c h h a s a s p r i n g
r a t e w h i c h w a s s e t t o i n c r e a s e t h e a i r p l a n e f l u t t e r speed b y t h e maximum a m o u n t f o r o n e e x t e r n a l s t o r e c o n f i g u r a t i o n . The store configuration is identified as GBU-8 c o n f i g u r a t i o n a n d h a s a n AIM-9 a n d l a u n c h e r o n t h e w i n g t i p s
external
a t S t a t i o n s 3 and 7 (Span S t a t i o n 1 2 0 1 , a n d 1 / 2 f u l l 370 g a l l o n t a n k s a t S t a t i o n s 4 a n d ( S t a t i o n s 1 and 91,
6
(Span S t a t i o n 71).
t h e GBU-8
The 370 g a l l o n t a n k s a r e l o a d e d w i t h
t h e c e n t e r bay empty and t h e f o r w a r d a n d a f t b a y s f u l l . decoupler pylon
is d e s i g n e d ,
from a s t r e n g t h s t a n d p o i n t ,
The
to
c a r r y a l l store l o a d i n g s which are c u r r e n t l y c a r r i e d on S t a t i o n s 3 , 4 , 6 and 7. T h i s addendum t o t h e b a s i c r e p o r t s u m m a r i z e s t h e f i n a l
were b a s e d upon t h e r e s u l t s o f t h e g r o u n d t e s t s , and r e p o r t s t h e r e s u l t s o f a n a l y s e s a n d t e s t s w h i c h were c o n d u c t e d t o e v a l u a t e t h e c a r r i a g e o f a s e c o n d e x t e r n a l analyses,
which
store on the decoupler pylon. The a d d i t i o n a l a n a l y s e s b a s e d upon t h e ground tests included flutter analyses and
2
