DEPARTAMENTO DE CINCIA E TECNOLOGIA AEROESPACIAL INSTITUTO TECNOLGICO

DEPARTAMENTO DE CIÊNCIA E TECNOLOGIA AEROESPACIAL INSTITUTO TECNOLÓGICO DE AERONÁUTICA DIVISÃO DE ENGENHARIA AERONÁUTICA DEPARTAMENTO DE PROJETOS DE AERONAVES PRJ – 30 Projeto e Construção de Aeromodelos Unit 4/8 Control & Stability & CG & Systems Prof. Adson Agrico Prof. Vitor Kleine CAP. Guilherme Soares LT. Ney Rafael Sêcco (in memoriam) São José dos Campos, SP, Brazil. March 2016

Controls Center of Gravity Schedule Stability Systems

Controls Center of Gravity Schedule Stability Systems

Airplane movements http: //www. classwork. villanova. edu/ME 4800/2010/Aero. Regular/Stability. Factors. htm

Flaps

Flaps

Flaps NACA 2412 Re 3 e 5 XFOIL Hinge @ 70% 0 o

Flaps NACA 2412 Re 3 e 5 XFOIL Hinge @ 70% 0 o 10 o 20 o

Flaps NACA 2412 Re 3 e 5 XFOIL Hinge @ 70% -20 o -10 o 0 o 10 o 20 o

• https: //www. youtube. com/watch? v=SXw. Vyxo rvno

Control Surfaces http: //www. aerospaceweb. org/question/history/q 0103. shtml

Control Surfaces YAW PITCH ROLL http: //www. aerospaceweb. org/question/history/q 0103. shtml

Sizing control surfaces

Sizing control surfaces Elevator and Rudder 30% ~ 35% of the chord All-moving tail

Sizing control surfaces

Sizing control surfaces

Sizing control surfaces At least 1/3 of rudder unblanketed

Controls Center of Gravity Schedule Stability Systems

Stability • Stability tendency to return to the equilibrium position STABLE UNSTABLE

Stability • Stability tendency to return to the equilibrium position STABLE UNSTABLE

Stability • Stability tendency to return to the equilibrium position STABLE UNSTABLE

Stability • Stability tendency to return to the equilibrium position STABLE UNSTABLE

Resultant Force & Moment F 10 F 2 F 3 F 8 F 9 F 7 F 4 F 5 F 6

Resultant Force & Moment F 10 F 2 F 3 F 8 F 9 F 4 Reference point F 7 F 5 F 6

Resultant Force & Moment F 10 FR 1 F 2 F 3 F 8 F 9 F 7 F 4 F 5 F 6

Resultant Force & Moment F 10 FR 1 F 2 F 3 F 8 F 9 F 7 F 4 F 5 F 6 MR 1

Resultant Force & Moment F 10 FR 2 FR 1 F 2 F 3 F 8 F 9 F 7 F 4 F 5 F 6 MR 2 MR 1

Resultant Force & Moment F 10 FR 2 FR 1 F 2 F 3 F 8 F 9 F 7 F 4 F 5 F 6 MR 2 MR 1 FR 2 MR 1 MR 2

Resultant Force & Moment F 10 FR 2 FR 1 F 2 F 3 F 8 F 9 F 7 F 4 F 5 F 6 MR 2 MR 1 FR 2 MR 1 MR 2

Resultant Force & Moment F 10 FR 2 FR 1 F 2 F 3 F 8 F 9 F 7 F 4 F 5 F 6 MR 2 MR 1 FR 2 MR 1 MR 2

Resultant Force & Moment NACA 2412 Re 3 e 5 XFOIL L. E.

Resultant Force & Moment NACA 2412 Re 3 e 5 XFOIL L. E. T. E.

Resultant Force & Moment NACA 2412 Re 3 e 5 XFOIL L. E. T. E.

Resultant Force & Moment NACA 2412 Re 3 e 5 XFOIL L. E. 24% c T. E.

Aerodynamic Center (AC) is the point where the pitching moment independs of the angle of attack. NACA 2412 Re 3 e 5 XFOIL L. E. 24% c AC T. E.

Where is the AC? AIRFOIL: 25% c

Where is the AC? AIRFOIL: 25% c cr /4 25% m. a. c. SURFACE: m. a. c. ct /4

Where is the AC? AIRPLANE: xac, w wing AC xac, h wing HT AC horizontal tail

Where is the AC? AIRPLANE: xac, w xac wing AC xac, h airplane AC wing HT AC horizontal tail

CG and AC Case 1: CG in front of AC AC CG

CG and AC Case 1: CG in front of AC L M AC CG

CG and AC Case 1: CG in front of AC AC CG

CG and AC Case 1: CG in front of AC L+DL AC CG

CG and AC Case 1: CG in front of AC L+DL M AC CG

CG and AC Case 1: CG in front of AC L+DL DL∙x M AC CG

CG and AC Case 1: CG in front of AC L M AC CG

CG and AC Case 1: CG in front of AC L M AC CG STABLE

CG and AC Case 2: AC in front of CG L M CG AC

CG and AC Case 2: AC in front of CG CG AC

CG and AC Case 2: AC in front of CG L+DL CG AC

CG and AC Case 2: AC in front of CG L+DL M CG AC

CG and AC Case 2: AC in front of CG L+DL DL∙x M CG AC

CG and AC L+2 DL Case 2: AC in front of CG M 2 DL∙x AC CG

CG and AC L+2 DL Case 2: AC in front of CG M 2 DL∙x AC CG UNSTABLE

• https: //www. youtube. com/watch? v=lks. DISv. C m. NI

CG and AC STABLE AC CG UNSTABLE CG AC

Static Margin • CG in front of CA How much? AC CG

Static Margin • CG in front of CA How much? AC CG

Static Margin • CG in front of CA How much? AC STATIC MARGIN: CG

Static Margin • CG in front of CA How much? AC STATIC MARGIN: CG SM>0 STABLE SM<0 UNSTABLE

Static Margin STATIC MARGIN BEHAVIOR SM < 0. 00 UNSTABLE. . . 0. 00 < SM < 0. 15 TOO SENSIBLE 0. 15 < SM < 0. 20 GOOD! 0. 20 < SM < 0. 25 TOO LAZY SM > 0. 25 TOO STABLE…

Controls Center of Gravity Schedule Stability Systems

Center of Gravity y m 6 m 5 P 6=(x 6, y 6) P 5=(x 5, y 5) m 7 P 7=(x 7, y 7) m 4 P 4=(x 4, y 4) m 8 m 3 m 1 P 8=(x 8, y 8) P 3=(x 3, y 3) P 1=(x 1, y 1) m 2 P 2=(x 2, y 2) x

Center of Gravity y m 6 m 5 P 6=(x 6, y 6) P 5=(x 5, y 5) P 7=(x 7, y 7) CG m 4 P 4=(x 4, y 4) m 8 m 3 m 1 m 7 P 8=(x 8, y 8) P 3=(x 3, y 3) P 1=(x 1, y 1) m 2 P 2=(x 2, y 2) x

Center of Gravity y m 6 m 5 P 6=(x 6, y 6) P 5=(x 5, y 5) P 7=(x 7, y 7) CG m 4 P 4=(x 4, y 4) m 8 m 3 m 1 m 7 P 8=(x 8, y 8) P 3=(x 3, y 3) P 1=(x 1, y 1) m 2 P 2=(x 2, y 2) x

Center of Gravity

Center of Gravity

Center of Gravity CG

Controls Center of Gravity Schedule Stability Systems

Systems • Propulsion: Glow APC 13 x 4 propeller Weight: 0, 050 kg O. S. 61 FX Engine Weight: 0, 550 kg Fuel Tank Weight: 0, 045 kg

Systems • Propulsion: Glow Tank position

Systems • Propulsion: Electric Battery Weight: 0, 188 kg APC 13 x 4 E propeller Weight: 0, 050 kg Turnigy G 25 Engine Weight: 0, 193 kg ESC Weight: 0, 081 kg

Systems • Electronics

Systems • Electronics Servo 1 right aileron Servo 2 engine elevator Futaba S 3003 Weight: 0, 037 kg Servo 3 Servo 4 left aileron Servo 5 rudder Servo 6 nose wheel Futaba S 3114 Weight: 0, 0078 kg

Systems • Electronics Servo 1 Servo 2 Futaba S 3003 Weight: 0, 037 kg Servo 3 Servo 4 Servo 5 Servo 6 Futaba S 3114 Weight: 0, 0078 kg

Systems • Electronics Servo 1 Servo 2 Futaba S 3003 Weight: 0, 037 kg Servo 3 Servo 4 Radio Servo 5 Servo 6 GROUND AIRPLANE Futaba S 3114 Weight: 0, 0078 kg

Systems • Electronics Receiver Servo 1 Servo 2 Futaba S 3003 Weight: 0, 037 kg Servo 3 Servo 4 GROUND Radio Futaba Receiver Weight: 0, 0098 kg Servo 5 Servo 6 AIRPLANE Futaba S 3114 Weight: 0, 0078 kg

Systems • Electronics Battery Receiver Servo 1 Servo 2 Turnigy Receiver Pack Weight: 0, 120 kg Futaba S 3003 Weight: 0, 037 kg Servo 3 Servo 4 Radio Futaba Receiver Weight: 0, 0098 kg Servo 5 Servo 6 GROUND AIRPLANE Futaba S 3114 Weight: 0, 0078 kg

Systems • Landing Gear TAILDRAGGER TRICYCLE Lighter Unstable Heavier Stable

Systems • Landing Gear

Systems • Landing Gear tailstrike angle > stall angle

Systems • Landing Gear tipback angle > stall angle tailstrike angle > stall angle

Systems • Landing Gear tipback angle > stall angle tailstrike angle > stall angle 8% ~ 15% of the weight 85% ~ 92% of the weight

Review • Control – Airplane movements. – Control surface sizing. • Stability – Aerodynamic center. – Static margin. • Center of Gravity • Systems – Propulsion. – Electronics. – Landing Gear.