Report of the Second Piloted Aircraft Flight Control System - Acgsc.org

With theae substitutions into equation (7) the dlffemntial equation8
for the systaa becorn,
Tho solution of these equrtions provldes the transfer -tion
the syrtm in operator fonn
of
An examhatian of this characteristic equation by mane of Routb
crit8rion, and by assuming tint aerodJmrwic damping is saw
although it t.ds to etabflise th syrtenn, it can be sham thnt
the stability of th system ia depedent upon the 'Chponhation
FautoP. The factor ia defined as
for the eystem being analysed. For the systcrar to be stable the
value of Cf muet be greater than 1, Neutral stability is obtained
when Cf equal 1,
By proper selection of linkage ratio8 the valw of Cf can, of course,
be varied. For the epecial case of Cf equal to 1 tbm wlll be sero
deflection of control valve slide mlativm to the slem for any
dieturbance of the eystem. If Cf is leer thn 1, the control mlva
slide movement vill be in the direction to oppore the oxt.mrl
dieturbance, adding energy to the system ond tending to destabilise
the -ah. This approaches the uncompensated -tan Mch hrs Cf
eqd to tern. A linkage ratio resulting in Cf baing greator thn 1
rill cause the control valve to mon in a direction not opposing
the disturbance. This ixxlicater a 1088 of onrrgy fian the ayetom and