KCSE 2019 Aviation Technology Paper 1 Questions with Marking Scheme

Aviation Technology Paper 1 (450/1)

SECTION A (44 marks)
Answer all the questions in this section.

1.        
   1. State two safety precautions to be observed with respect to dressing when operating a grinding machine.(1 mark)
   2. Give the classes of fire likely to occur in each of the following areas:
      1. Aircraft technical records
      2. Paint store (1 mark)
   3. Outline two mandatory safety equipment to be carried by an aircraft flying over water (1 mark)
2.         
   1. State four ways of preventing accidents in an aviation environment. (2 marks)
   2. Highlight two roles of a flight dispatcher. (1 mark)
3.        
   1. Outline three reasons for abnormal moods and poor decision-making in aviation industry(3 marks)
   2. Outline three adverse effects of cumulonimbus clouds on an aircraft in flight. (3 marks)
4.                       
   1. Sketch and label the following aircraft hardware.
      1. Countersunk rivet
      2. Raised head screw(4 marks)
   2. Outline the procedure of annealing steel(2 marks)
5. State the use of each of the following tools:
   1. Odd leg callipers
   2. Flat screw driver (1 mark)
6.                
   1. Differentiate between propeller driven and pure jet engine methods of thrust generation,(2 marks)
   2. Explain why propeller blades are twisted. (1 mark)
7.                            
   1. Explain the functions of each of the main structural member of the semi-monocoque aircraft construction, (5 marks)
   2. Name four methods of non destructive testing used in aircraft inspection (2 marks)
8.                         
   1. State four methods used in aircraft navigation (2 marks)
   2. With regards to aircraft systems, complete Table 1.
      

      Part	System	Function
      Pump
      Transformer
      Thermocouple
      Actuator

9. With the aid of labelled sketches, show the airflow over each of the following body shapes:
   1. Flat plate(2 marks)
   2. Stationary sphere (2 marks)
   3. Asymmetrical airflow at 0 angle of attack (2 marks)
10.                
    1. Draw the following types of lines used in engineering drawings:
       1. Centre line
       2. Hidden detail line(1 mark)
    2. Figure 1 shows two views of an aircraft part drawn in first angle orthographic projection. Draw the plan
       

SECTION B (56 marks)
Answer any four questions from this section in the space provided.

11.              
    1. Name four aircraft systems that use pneumatic power.(2 marks)
    2. With the aid of sketches, describe the following types of landing gear configuration:
       1. Tri-cycle
       2. Conventional (6 marks)
    3. Explain how steering is achieved in each of the gear configuration in 11(b).
       1. Tricycle
       2. Conventional (6 marks)
12.                     
    1. Describe each of the following business ventures in aviation, stating two merits and two demerits for each
       1. Cargo and courier services
       2. Aircraft maintenance shop (6 marks)
    2. Outline three effects on the human body due to high altitude flights. (3 marks)
    3.        
       1. State six functions of the Kenya Civil Aviation Authority (KCAA). (3 marks)
       2. Identify any two categories of airports in Kenya and explain the kind of inspection carried out in each category. (2 marks)
13.             
    1. With regards to the six basic flight instruments:
       1. show the typical layout
       2. state the functions of each of the flight instruments (12 marks)
    2. Explain the meaning of each of the following terms as applied to aviation:
       1. VFR
       2. IFR (2 marks)
14.              
    1. Sketch each of the following aircraft wing forms:
       1. Anhedral
       2. Gull wing (3 marks) 
    2. With the aid of a sketch, describe the formation of induced drag,(9 marks)
    3. Illustrate each of the following types of flaps:
       1. Single slotted flap
       2. Split flap (2 marks)
15. Figure 2 shows three orthographic views of an engine mounting bracket. Draw the mounting bracket full size in isometric projection taking X to be the lowest point. (14 marks)
    

MARKING SCHEME

1.      
   1.                  
      • Do not wear loose clothing.
      • Always use safety goggles.
      • Wear safety boots.
        (Any 2 x ½) = (1 mark)
   2.       
      • Aircraft technical records office
        Class A fire
      • Paint store
        Class B fire
        (Any 2 x ½)= (1 mark)
   3. Mandatory safety equipment
      • Life jackets
      • Life rafts
      • Distress signals
        (Any 2 x ½) =(1 mark)
2.             
   1.              
      • Seek assistance if not sure
      • Avoid hasty movements
      • Apply safety regulations
      • Re-training on equipment
      • Do not take wrong orders to operate equipment
      • Exercise caution
      • Love your job
        (Any 4 x ½)=(2 marks)
   2.            
      • Flight planning
      • Release of aircraft
        (Any 2 x ½)= (1 mark)
3.           
   1.               
      • Fatigue
      • Drug abuse
      • Stress
        (Any 3 x 1)= (3 marks)
   2.             
      • Poor communication due to lighting and thunder.
      • Poor visibility due to heavy rain or clouds.
      • Change of direction or instability due to turbulence.
        (Any 3 x 1)=(3 marks)
4.              
   1.                
      
      2 sketches @1(2x1) = 2 marks
      4 labels @½ (4 x ½)= 2 marks
      total = 4 marks
   2. Procedure of annealing steel
      • Heat the metal to just above the upper critical point.
      • Cool it very slowly in ash, sand or fumace, i.e. quench slowly.
        (Any 2 x 1) =2
5.                
   1. Uses of odd leg calipers
      • To find the center of a circular rod.
      • For transferring measurements.
      • For drawing parallel lines.
        (Any 1 x ½) = ½ mark
      • Uses of flat screw driver
      • Tightening or making loose flat head screws with straight slots.
        (Any 1 x ½) = (½ mark)
6.              
   1.           
      • Pure jet engines give a big acceleration to a small mass of air.
      • Propeller driven engines give a small acceleration to a big mass.
      • Fire wall (fire bulkhead) separate heat areas.
        (Any 2 x 1=2 marks)
   2. Propeller blades are twisted to ensure equal work is done along the whole blade length. (1 mark)
7.                   
   1. Functions of the structural members of the semi-monologue.
      • Longerons take up bending loads.
      • Frames give the aircraft its circular shape and provide attachment for longerons and stringers.
      • They give the aircraft its rigidity.
      • Stringers give support, strength and provide attachment to the aircraft skin.
      • Bulkheads provide rigidity and partitioning.
      • The skin provides the aircraft structural cover and takes up aerodynamic loads.
        (Any 5 x 1 = 5 marks) 
   2.             
      • Visual
      • Ultra sonic
      • Radiographic (x-ray)
      • Magnetic particle
      • Dye penetrant
      • Eddy current
        (Any 4 x ½ )= (2 marks)
8.             
   1. Methods of aircraft navigation:
      • Dead reckoning
      • Astral
      • Visual
      • Radio 
      • Global position GPS
        (Any 4 x ½)=(2 marks)
   2.      
      

      Part	System	Function
      Pump	Fluid system lubrication pneumatic hydraulic	To create motive force in the fluid system, or lubrication system, etc.
      Transformer	Electrical	Steps up or down the voltage
      Thermo couple	Instrument Fire detection	Measures temperature
      Actuator	Pneumatic or hydraulic	Converts fluid pressure into mechanical movement (work)
      	4 x ½=2 marks	4 x ½=2 marks

      Total 2 x 2= (4 marks)
9.                 
   1. Flat plate at 90° to the relative airflow.
      
   2. Stationary sphere
      
   3. Asymmetrical airflow at 0° angle of attack.
      
10.              
    1. LINES USED IN DRAWING
       ___ _ ___ _ ___ _ ___ _ Centre line
       _ _ _ _ _ _ _ _ _ _ _ _ _  Hidden details line
       (2 x  ½ =1 mark)
    2.           
       
       (2 marks)
11.                       
    1. Aircraft systems that use pneumatic power are:
       • Air conditioning system
       • Pressurization system
       • Aerofoil and engine anti-icing and de-icing system
       • Gas turbine engine starting system
       • Aircraft emergency systems
         (Any 4 x ½)=(2 marks)
    2.                  
       1. Tri-cycle
          
          • This is an arrangement where a nose landing gear is fitted in front of two main landing gear.
            Correct sketch - 2 marks
            Explanation - 1 mark
            Total = 3 marks
       2. Conventional
          
          
          • This is an arrangement where the main wheels are ahead of the tail wheels (3 marks)
    3.                 
       1.                 
          • Steering to the right.
          • The pilot steps on the right hand brake pedal.
          • The right hand main wheel stops moving (stationary).
          • The nose wheel turns to the right, as the aircraft steers to the right and vice versa
            (3 x 1)=(3 marks)
            
            
          • Using a steering pad
          • The pilot steps on the right brake pedal
          • The right hand main wheels stop moving
          • The tail wheel turns to the right as the aircraft steers to the right and vise versa
            (3 x 1)=(3 marks)
12.           
    1.              
       1.          
          • Cargo And Courier Services
            • This is the business of transporting cargo, letters and money. (1 mark)
          • Advantages 
            1. Aircraft are a fast means of transport.
            2. Aircraft transport is reliable.
          • Disadvantages
            1. Some cargo can be hazardous or poisonous which may not be carried on aircraft. This needs a lot of care and safety in handling.
            2. Some cargo can be considered a security threat for example explosives.
               (4 x ½) = (2 marks)
       2.               
          • Aircraft maintenance shops
            • For the repairs, servicing and painting of aircraft (ground handling) (1 mark) 
          • Advantages
            • Easy availability of clients
            • Closeness to the market because of many small aircraft operators
            • Provides direct employment to qualified personnel
              (availability of skilled labour).
          • Disadvantages
            • Expensive to set up
            • Stiff competition from established operators
            • Expensive spare parts
            • Legislative (licensing) challenges
              (4 x ½) = (2 mark)
    2. Effects on human body
       1. Low temperature which may lead to freezing.
       2. Low pressure which leads to decrease in oxygen, may cause hypoxia and anoxia.
       3. Low humidity at high altitudes causes itching, sore throat and dry skin.
          (Any 3 x 1)=(3 marks)
    3.         
       1. Functions of KCAA
          1. Licensing of air services.
          2. Provision of air navigation services.
          3. Ensuring safety and efficiency in Kenyan airspace (air traffic control services)
          4. Accident investigation
          5. Aircraft registration
          6. Enforcing technical standards
          7. Examination of technical personnel
          8. Advising the government of matters concerning civil aviation
             (Any 6 x ½)= (3 marks)
       2.  
          • Categories of airports in Kenya.
          • Category A - inspected daily
          • Category B - inspected weekly
          • Category C - no inspection
          • Category D - private
            (Any 2 x ½) = |(2 marks)
13.                     
    1.            
       
       Correct six = 6 x ½= 3 marks
       Arrangement = 6 x ½ = 3 marks
       Total 6 marks
       
       Functions
       1. Altimeter
          • Shows aircraft height above a particular point (datum)
       2. Airspeed indicator (ASI)
          • Indicates the aircraft speed relative to surrounding air.
       3. Heading indicator (directional grid)
          • Displays the aircraft heading with respect to geographical North.
       4. Turn indicator
          • Displays direction of turn and rate of turn.
       5. Vertical speed
          • Senses changes of air pressure and displays the rate of aircraft climb or descent
       6. Attitude indicator (artificial horizon)
          • Shows aircraft attitude relative to the horizon (nose up or nose down)
            6 x 1= 6 marks
    2.              
       1. VFR      
          • Visual flight rules. Flying. Without the aid of instruments, using land marks.
       2. IFR
          • Use of navigational instruments (instrument flight rules)
          • Use of flares or lights
          • Use of painted signs
            2 x1= (2 marks)
14.                   
    1.                   
       1. anhedral 
          
       2. Gull wing
          
          2 x 1=(2 marks)
    2.               
       1.                  
          • Induced drag is formed as a result of lift productions and high angles of attack.
          • This is the formation of 3 dimensional airflow over the wing, that is:
            1. Flow above the wing having low pressure.
            2. Flow under the wing having high pressure.
            3. High pressure flow upwards at the wing tip.
               
               The flow at the wing tip forms a vortex (induced drag)(9 marks)
               Explanation (description) (5x l=5 marks)
               Sketch as detailed areas (4 x1 = 4 marks)
    3.                
       1. Single slotted flap
          
          (1½ mark)
       2. Split flap
          
          (1½ mark)
          (3 marks)
15.                      
                
    1. Correct faces (14 x ½) = 7 marks 
    2. Correct projections (1 x 1) = 1 mark
    3. Correct measurements = 2 marks
    4. Circular features drawn correctly 5 x ½ = 2½ marks
    5. Current position of 'X'(1 x ½ ) = 1 mark
    6. Line work and neatness = ½mark
       Total 14 marks
       (14 marks)