KCSE 2012 Aviation Technology Paper 2 with Marking Scheme

STATION 1

INSTRUCTIONS

The figure below shows an assembly drawing of an aircraft steering cylinder with serimmy damping provision. On the drawing paper provided sketch in good proportion the exploded view of the cylinder. Label four parts.   (10 marks)

STATION 2

INSTRUCTIONS

Using the tools, materials and equipment provided make the bracket as shown in figure 1.   (10 marks)

STATION 3

INSTRUCTIONS

Carry out the following tasks using the materials, tools and equipment provided.

1. Measure and mark 40mm on the strip labelled A, B, C and D. Let the examiner check your work.   (2 marks)
2.  
   1. Hold the strip A at the 40mm mark in the bench vice.
   2. Count the number of cycles to fracture by bending from maximum Left to maximum Right.
   3. Complete the table provided for A.
   4. Repeat the process in b(i) to (iii) for B, C and D.
      

      Strip	No of cycles	Mechanical Property	Material	Application
      A
      B
      C
      D

      (8 marks)

STATION 4

INSTRUCTIONS

Study the model of an aircraft system provided and carry out the following:

1.  
   1. Operate the part marked J in the forward direction and record your observations.   (1 mark)
   2. Relate your observation in a(i) to an aircraft in flight.   (1 mark)
2.  
   1. Operate the part marked J in the rearwards direction and record your observations.   (1 mark)
   2. Relate your observations in b(i) to the aircraft in flight.   (1 mark)
3. Disconnect point P on part N and connect to H.
   Repeat (a) and (b) above and record your observations   ( 4 marks)
4.  
   1. State the functions of M in (a) and (c).   (1 mark)
   2. Name the systems in (a) and (c).   (1 mark)

STATION 5

INSTRUCTIONS

Using tools, equipment and parts provided demonstrate to the examiner the procedure of replacing the piston rings.
(10 marks)

STATION 6

INSTRUCTIONS

Connect the set up as shown in figure 2.
Let the examiner check your work.            (2½marks)

1.  
   1. Open valve A gradually until pressure gauge reads 5psi to 10psi and 15psi respectively and record four observations.
      (4 marks)
   2. State the reasons behind your observations in a (i)
   3. Explain the principle behind your observation (2 marks)
2. Relate the experiment to three aircraft systems.  (1½ marks)

STATION 7

INSTRUCTIONS

An aircraft flying from A to B at 360 knots encounters a wind 330° at 60 knots.

1. On the map provided plot a labelled vector diagram and determine each of the following:
   1. track bearing;
   2. type of wind;
   3. two effects of the wind.   (8 marks)
2. State two most appropriate instruments used for the navigation of the flight.     (2 marks)

STATION 8

INSTRUCTIONS

Study the Aerodromes facilities and operations sketch attached and complete the tables below.

1. Name the facilities marked 1, 2, 3, 4 and state the use of each.   (4 marks)
   

   Facility	Use

2. Identify operational activities of the aircraft labelled A, B, C and D and state the reason for each observation.   
   (4 marks)
   

   Operation Activity	Reason

3. State the function of the facility labelled E and F  (2 marks)
   

   Facility	Function

STATION 9

INSTRUCTIONS

Connect the components provided as shown in the circuit below.
Let the examiner check your work.   (3 marks)

1.  
   1. Select switch S, to on position and state what happens.   (1½marks)
   2. Replace L₁ with L₂ and state what happens.  (1½ marks)
   3. Repeat a(i) with L₃ load and state what happens.  (1½ marks)
2. State three reasons behind your observations.  (1½ marks)
3. Relate the experiment to two aircraft systems.    (1 mark)

STATION 10

INSTRUCTIONS

Using the tools, equipment and materials provided carry out the following.

1.  
   1. Check and record the roundness of the bar A using the set-up.
   2. Repeat a(i) for bar B.
   3. Compare the observations between the two bars.
   4. State the reasons behind your observations.                 (4 marks)
2. Measure and record the following measurements on the Vee block on areas labelled D, E, F, G and H as shown below.
   (5 marks)
   
3. State two safety factors to observe while using a dial test indicator.    (1 mark)