AAE 556 Aeroelasticity Lecture 13 Control effectiveness Aeroelastic

AAE 556 Aeroelasticity Lecture 13 Control effectiveness Aeroelastic tailoring Purdue Aeroelasticity 13 -1

Control effectiveness rigid wing/springs model aile ron Purdue Aeroelasticity 13 -2

Invert the aeroelastic stiffness matrix Then solve for the two deflections Purdue Aeroelasticity 13 -3

Swept wing lift due to full-span aileron deflection Purdue Aeroelasticity 13 -4

Lift expression algebra Purdue Aeroelasticity 13 -5

Aileron effectiveness measured as aileron lift effectiveness Purdue Aeroelasticity 13 -6

The reversal dynamic pressure solution Purdue Aeroelasticity 13 -7

Example - effects of sweep on aileron effectiveness unswept wing divergence at 250 psf. (qo) Reversal at 150 psf. Purdue Aeroelasticity 13 -8

Summary-swept wing control effectiveness i wing sweep changes the divergence dynamic pressure and lift effectiveness i sweepback stabilizing - slight sweep only i Sweep forward is aeroelastically destabilizing i sweepback reduces lift effectiveness and control effectiveness i Sweep forward increases lift effectiveness and control effectiveness Purdue Aeroelasticity 13 -9

Aeroelastic tailoring Purdue Aeroelasticity 13 -10

Tailoring for performance Purdue Aeroelasticity 13 -11

Madeleine Vionett (1875 -1975) i Perfected the bias cut for clothing i Cut on diagonal form fitting Purdue Aeroelasticity 13 -12

Early attempts Hi. MAT i 1974 -1979 time frame i Remotely piloted i Composite skins Purdue Aeroelasticity 13 -13

The X-29 Purdue Aeroelasticity 13 -14

Benefits Purdue Aeroelasticity 13 -15

Stiffness tailoring model Purdue Aeroelasticity 13 -16