Dynamic Stability TPB

8/19/2019 Dynamic Stability TPB

1/39

DYNAMIC STABILITY


2/39

Dynamic stability is defined as the tendency

of the amplitudes of the perturbed motion of

an airplane to decrease to zero or to values

corresponding to a new steady state at some

time after the cause of the disturbance has

stopped.


3/39

A dynamic stability criterion is defined as a

rule by which perturbed motions of the

airplanes are separated into the categories of

stable, neutrally stable or unstable

Airplane response is defined as the variation

with time of motion variables relative to some

given steady state flight condition as a result

of an externally or internally generated

disturbance


4/39


5/39


6/39


7/39

Dynamic Stability Criteria

1. A linier system is stable if and only if thereal parts of the roots of the characteristic

euation of the system are negative

!. A linier system is convergent "stable# ifthe roots of the characteristic euation of

the system are real and negative


8/39

$. A linier system is divergent "unstable# if

the roots of the characteristic euation of

the system are real and positive%. A linier system is oscillatory convergent

"stable# if the real parts of the roots of the

characteristic euation of the system are

negative

&. A linier system is oscillatory divergent

"unstable# if the real parts of the roots of

the characteristic euation of the system

are positive


9/39

'. A linier system is neutrally stable if one

of the roots of the characteristic euation

of the system is zero or if the real parts ofthe roots of the characteristic euation of

the system is zero


10/39


11/39

(ongitudinal Stability


12/39


13/39


14/39


15/39


16/39


17/39

(ongitudinal Approximations

)hugoid


18/39


19/39

Short )eriod


20/39


21/39


22/39


23/39


24/39


25/39


26/39

(ateral Stability


27/39


28/39


29/39


30/39


31/39


32/39


33/39


34/39

*+AS

- %///0 lb

C at !& 2AC3x !4$000 slug.ft

!

3y !1&000 slug.ft!

3z %%4000 slug.ft

!

3xz 0 slug.ft!

S 5%& ft!

b 5' ft

10.1 ftc

XXX = NIM 3

terakhir


35/39


36/39


37/39


38/39


39/39

a. Apa6ah pesawat ini stabil stati6 bai6 secara

longitudinal dan lateral7dire6sional 8 9elas6an :

b. Apa6ah pesawat ini stabil dinami6 bai6 secaralongitudinal dan lateral7dire6sional 8 9elas6an :

c. ;agaimana6ah 6ualitas dari modus gera6 short period

8 9elas6an :

d. ;agaimana6ah pengaruh dari Cn

Dynamic Stability TPB

Documents

Transcript of Dynamic Stability TPB