1.Efficiency: pg8
a) Ratio between absorbed work and ideally absorbed work for constant maximum reaction Rmax
b) Ratio between absorbed heat and ideally absorbed heat for constant maximum reaction Rmax
c) Work absorbed by the system
d) Heat absorbed by the system
2.What is the function of the torque link? pg8
a) Ensure the wheel (rotation plane) is perpendicular to the surface
b) Increase the efficiency of the system
c) Increase the work absorbed by the system
d) Allow aircraft to be almost horizontal when parked or ground maneuvering
3. Nose wheels: A- Makes the fuselage follows the nose B- Allow aircraft to be almost horizontal when parked or ground maneuvering
A y B true
A y B false
A true B false
A false B true
4. What is true about shimmy?
a) No shimmy up to 1.4vstall
b) Is lateral oscillation of a wheel around its orientation axis
c) Twin wheels increase the shimmy
d) There aren’t any avoiding methods
5. Where can you keep a retractable gear? pg8
a) In the wing
b) In the fuselage
c) In nacelles behind the engine
d) All of the above are corrects
6. What kind of wheels arrangement are usually used in transport aircrafts? pg9
a) Single main
b) Bicycle
c) Tricycle
d) Multi-bogey
7. What kind of damping systems are used in aircraft?
a) Bungee Cords
b) Spring Steel Leg
c) Torsion bar
8. In what kind of damping system the bar absorbs the loading and the energy is dissipated into the fuselage? pg9
d) In none of the above
1. Which methods to transmit power are used on aircrafts? pg10
a) Electrical methods and mechanical methods
b) Fluid power (Hydraulic and pneumatic methods)
c) Magnetic and friction methods
d) A and B are correct
2. Which one IS NOT an ADVANTAGE of hydraulic systems? pg10
a) Useful for small forces
b) Easy installation
c) Easy control
d) Instantaneous transmission
3. Hydraulic VS Pneumatic Systems. Which one is INCORRECT?
a) POWER RANGE (power of pneumatic system is more limited)
b) ACTUATION SPEED (hydraulic system is faster)
c) WORKING TEMPERATURE (pneumatics can work at higher temperatures)
d) INSTALLATION COST (compressors are more expensive)
4. Pascal ́s Law says:
a) The pressure exerted anywhere in a confined compressible fluid is transmitted equally in all directions throughout the fluid such that the pressure ratio (initial difference) remains the same
b) The pressure exerted anywhere in a confined incompressible fluid is transmitted equally in all directions throughout the fluid such that the pressure ratio (initial difference) remains the same
c) The pressure exerted anywhere in a confined compressible fluid is transmitted equally in all directions throughout the fluid such that the pressure ratio (initial difference) remains the same
d) The pressure exerted anywhere in a confined incompressible gas is transmitted unequally in all directions throughout the gas such that the pressure ratio (initial difference) remains the same
5. Which are the missions of Hydraulic Fluids?
a) Transmissor media of the hydraulic pressure and evacuate heat
b) Lubricate moving parts and seal joints and gaps
c) A and B are correct
d) A and B are incorrect
6. ........................ convert fluid pressure into linear motion pg10
a) Linear actuator
b) Linear selector
c) Rotary selector
d) Spool valve selector
7. Which flow control device prevents backflow?
a) Hydraulic Locks
b) Non-return valves (NRV)
c) Pressure Relief Valves (PRV)
d) Pressure Regulators
8. Which are desired properties of Hydraulic Fluids? pg11
a) Low viscosity, Ressitance to heat, flammable and good lubricant properties
b) High viscosity, Ressitance to heat, flammable and good lubricant properties
c) High viscosity, Ressitance to heat, Non-flammable and bad lubricant properties
c) High viscosity, Ressitance to heat, Non-flammable and good lubricant properties
1.- Which of the next gear configurations is more stable when the aircraft is turning?
a)Trycycle(wheel on te nose)
b)Multi Bugey
c)Quadricycle
d)Tail drabber
2.-What do you have to take into account in order to design the base of the gear?
a)Weight distribution in the plane
b)Aircraft weight whatever is the gravity centre
c)The ground speed at wich the aircraft lands
d)Only the distance of the track
3.-Cuál es una de las ventajas del tren fijo? pg11
a)Construction simplicity
b)Low dynamic resistance during the flight
c)Easy management
d)Construction complexity
4.-¿Wich are the most important factors in order to desing the gear when landing? pg12
a)mass, Vertical velocity at touch down and Forward velocity at touch down
b)deceleration when landing, vertical velocity and forward velocity
c)mass, location of the gravity centre and deceleration
d)Only the weight of the aircraft
5.-How is a Spring Steel Leg ?
a)It uses liquids like liquid springs
b)It uses an elastic material that can whitsatnd torsional loading
c) Flexible tube screwed to the aircraft fusselage and it has a very low maintenance
d) Some bungee cord rings or rubber blocks inside a tubular housing connected to the aircraft structure.
6.-Advantages of the liquid springs? pg12
a) strong fatigue problems and big size
b) Los temperatures of the liquid
c) Construction simplicity
d) Few fatigue problems and small size
7.- The oleo-pneumatic shock absorbers, with unseparated oleos give us: pg12
a) Minimun extensión in flight and complex to manufacture
b) Maximum extension in flight and is easy to manufacture
c) Liquid temperatura rises when landing
d) Rebound is imposible with this shock absorber
8.-Some disadvantages of the liquid springs are:
a) They are very small
b) Temperature change fluid properties and therefore the damping prop and and sock absorbers must be pressurized with the gear extended
c) Sock absorbers must be pressurized without the gear extended
d) They are very fragile
