AIRCRAFT STABILITY AND CONTROLQUESTION BANKUNIT IPART-A
1.Define stability
2.
State three modes of stability3.Define static stability4.Define dynamic stability5.Difference between static stability and dynamic stability
6.
What is meant by 'degree of freedom'7.State two conditions for static longitudinal stability and indicate themwith a Plot8.The statically stable aircraft may be dynamically stable or unstable.Similarly dynamically stable aircraft may be statically stable orunstable". Are both statement true9.Write the types of axis components in aircraft10.What is coordinate transformation11.Tail volume ratio
PART-B
1.Derive the axis component of entire airplane2.Derive the force and moment equation act in an aircraft3.Explain the basic concepts of static and dynamic stability withexample
4.
Explain the longitudinal static stability in detail5.Explain the conditions of longitudinal static stability
6.
Derive the equation for overall contribution of aircraft pitchingmoment about c.g
7.
Derive contribution of wing of aircraft pitching moment8.Derive the contribution of tail of aircraft pitching moment9.Explain the contribution of fuselage of aircraft pitching moment10.Define centre of gravity, aerodynamic centre, centre of pressure
UNIT IIPART-A
1.
Why does an airplane require vertical tail?2.What is porpoising oscillation?3.Explain 'snaking mode'.
4.
Define neutral point?
5.
Define static margin?6.Define elevator power?7.What is control effectiveness8.What is stick fixed9.What is stick free
10.
Difference between stick fixed vs. stick free11.What is hinge moment?
PART-B
1.Derive the equation for elevator free factor2.Derive the hinge moment coeffient of elevator
3.
Derive the equation for the control effectiveness of elevator4.Explain stick force per g in detail
5.Explain the term stick force gradient
6.
Explain the power effects in jet and propeller engine7.Derive the neutral point equation for stick free condition8.What is aerodynamic balancing? Explain any 3 in detail
9.
A wing body model is tested in a subsonic wind tunnel. The lift is foundto be zero at a geometric angle of attack α = -1.5° . At α = 5° the C
L
is measured as 0.52, the moment coefficient about the CG aremeasured as -0.01 and 0.05 for α = 1 and 7.88° respectively. TheC.G. is located at 0.35 C. Calculate the location of the aerodynamiccentre and the value CM.10.Show that elevator angle for trim is given by:
UNIT IIIUNIT IIIPART A
1.What is stability derivatives2.Mention the types of stability derivatives3.What is mean by freeing the stick4.Write the effects of freeing the stick5.Write the types of maneuvers6.What are the types of disturbance faced by aircraft
7.
Define phugoid motion8.What is control surface flutter
PART B
1.
Write the equations of stability derivatives relevant to longitudinalstability
2.
Write the equations of stability stability derivatives of lateral stability
3.
Discuss various stability derivatives relevant to longitudinal stability4.What are the effects caused during pull up and pull down maneuvers5.Derive the equation of motion of rigid aircraft
6.
Derive the various stability derivatives relevant to lateral dynamics.
UNIT IV
1.What is dihedral2.Define dihedral effect3.What is side slip4.Difference between dihedral and anhedral5.What is One Engine Inoperative condition
6.
What is frise aileron7.What is Rudder locks8.What is Dutch roll9.What is Spiral divergence10.What is auto rotation1.Describe Dihedral effect and aileron reversal.2.Discuss about adverse yaw and crosswind landings3.Write short notes on :
a.
One Engine Inoperative condition
b.
Spin recovery
4.
Write short notes on : Rudder locks and Dutch roll approximation
5.
Discuss about Slip stream rotation of nose mounted propellers 6.Write short notes on:
a.
Autorotation
b.
Dutch rollc.Spiral divergence
7.
What are the various requirement of rudder?8.Explaina.Rubber lock and Dorsal fin.
b.
Rubber fixed directional static stability.9.Determine the neutral point during flight test
10.
Difference between frise aileron and differential aileron11.Explain in detail about routh discriminant
12.
An airplane W/s = 3000 N/m2, V = 450 kmph flying at 6 km attitudehas the characteristic equation in longitudinal mode of the form(λ
2
+ λ + 6) (3 λ
2
+ λ + 1) = 0. Find the period and time to dumpand comment whether oscillation can be ignored.
13. R
udder requirement in directional control
UNIT VPART A
1.What is the role of modern control theory2.Define space modeling3.What is autopilot
4.
What is stability augmentation system5.What is purpose of SAS6.Define inertia coupling7.State the terms controllability and absorbability in auto pilot8.What is the purpose of feedback system9.What are basic instruments present in autopilot system10.What is closed loop and open loop system
PART B
1.What is the role of modern control theory towards the advancement of aerospace industry
2.
Explain in detail about Auto pilot system design in detail3.Discuss the contribution of modern control theory in development of auto pilot4.Explain in detail about stability augmentation system5.Discuss the problem in designing the auto pilot system6.Explain about flexibility effects in aircraft7. Discuss the application of classical control theory in development of auto pilot design8.Explain in detail about basic instrument in Auto pilot system
9.
Aerospace engineers typically are employed in the aerospace product and parts industry, although their skills are becoming increasingly valuable in other fields. For example, in the motor vehicles manufacturing industry, aerospace engineers design vehicles that have lower air resistance and, thus, increased fuel efficiency.