KCSE 2019 Aviation Technology Paper 2 Questions with Marking Scheme

Aviation Technology Paper 2

STATION 1

INSTRUCTIONS

Figure 1 shows an exploded view of a hydraulic system hand pump. In the space provided:

1. sketch in good proportion a typical pictorial view of the hand pump. (8 marks)
2. name four visible parts on Figure 1 after assembly (2 marks)
   

STATION 2

INSTRUCTIONS

Using the tools, equipment and materials provided, fabricate the aircraft VHF radio compartment tray as shown in Figure 2. (10 marks)

STATION 3

INSTRUCTIONS

Using the multimeter and assembly 'K' provided, perform the following tasks: (1 mark)

1.                
   1. Set the multimeter to AC 220- 250 volts.
   2. Plug assembly 'K' to the power source. Let the examiner check your work
2. Select the main source and component 'A' to 'On' position. Measure and record the voltage across(1 mark) (
   1. T and T,
      Voltage
   2. T and T.
      Voltage
      Switch of component A
3. Connect terminals T, and T, to points 1 and 2 respectively on component (3 marks)
   1. Measure and record voltage across terminal T, and point 2.
      Voltage
   2. Select component'A' to On position Record the observations.
      Observations
   3. Switch "off" component 'A'. Replace terminal T, with TSelect component 'A' to 'On' position and record the observations.
      Observations 
   4. Measure and record voltage across terminal T and T
      Voltage
   5. Select component'A' to off' position. Disconnect terminals T and T from points 1 and 2 on component 'C'. Let the examiner check your work (3 marks)
4. State:
   1. The reasons for the observations in c(i), (ii) and (iii)
      Reasons
   2. Two systems where the sytem is applicable on an aircraft electrical system.
      Systems 1.
      Systems 2
      (2 marks)
   3. Identify components A, B, C and D on assembly 'K'
      Components A
      Components B
      Components C
      Components D

STATION 4

INSTRUCTIONS

Using part labelled 'E' and the precision tools provided, perform the following tasks: (2 marks)

1.            
   1. Identify part "E"
      Identification
   2. State the type
      Type ......
   3. Give the use:
      Use.
   4. State the importance of taper angle.
      Taper angle importance
2. Take the measurements and complete table 1 (6 marks)
   Table 1
   

   ITEM	DESCRIPTION OF MEASUREMENT	MEASUREMENT
   i	External diameter of outer race.
   ii	Width of outer race
   iii	Bore diameter
   iv	Taper Angle.
   v	Thickness of the face.
   vi	Gap between inner and outer race.

3. State four rejection criteria for part E criteria. (2 marks)

STATION 5

INSTRUCTIONS

Using tools and component 'F' provided, perform the following tasks: 

1. Study the tool labelled 1 and identify: (2 marks)
   1. Name of the tool
   2. Use of the tool
   3. Maintenance check required
   4. Type 
2. Study component 'F' and identify: (1½ marks)
   1. Component
   2. Type
   3. System applicable
3. Dismantle component "F"
   1. Identify parts G, H, J, K and I (2½ marks)
   2. State the use of parts painted white and blue (1 mark)
      White
      Blue
   3. Examine parts G, J, K and Land identify the maintenance checks for each. (2 marks)
      Part G
      Part J
      Part K
      Part L
4. Record two failure indicators for component F" during engine run (1 mark)
   Indicators:

STATION 6

INSTRUCTIONS

Using the tools and instruments labelled M and N, perform the following tasks:

1. Study the instruments 'M' and 'N'. Record the observations. (1 mark)
   Observations:
2. Remove the instruments cover. Study the mechanisms and operations of each and answer questions b(i) to b(iv) (8 marks)
   1. State principle of operation
   2. Identify operating mechanism
   3. Determine the sensitivity
   4. Identify and state the function of four common parts.
      

      Part	Function
      1
      2
      3
      4

   5. State the instrument grouping
3. State two physical checks that should be carried on instruments 'M' amd 'N' on the aircraft before flight (1 mark)
   Checks:

STATION 7

INSTRUCTIONS

Using the tools and component provided, perform the following tasks:

1. Study component 'P and identify: (2 marks)
   1. The component
   2. Component type
   3. System where applicable
   4. Type of aircraft where used
2.                  
   1. Dismantle the component P. Let the examiner check your work. (1 mark)
   2. Identify parts painted white, blue, red and green. (2 marks)
      White
      Blue
      Red
      Green
   3. Identify four defects on component P (2 marks)
      Defects:
   4. Assemble component.P'. Let the examiner check your work. (1 mark)
   5. Give four routine checks to be carried on component P. (2 marks) 
      Routine check

STATION 8

INSTRUCTIONS

Using the material labelled 'Q' and hardware labelled 'R', perform the following tasks 

1. Study the structure of material 'Q' and answer question a(i) to (iii) (4 marks)
   1. Identify the material.
      Material
   2. State the reason for use in aircraft construction.
      Reason
   3. Sketch and label the cross section through the material in the space below.
2. Study hardware 'R' and answer questions b(i) to b(iii). (6 marks)
   1. Identify the hardware.
      Hardware ...
   2. State the condition of the hardware.
      Condition
   3. Sketch and label the external thread profile in the space below.

STATION 9

INSTRUCTIONS

Using the airport model labelled 'S', aircraft model call sign N123QZ labelled as shown in table 2, perform the following tasks. and tower instructions

1. Demonstrate and explain to the examiner the procedure of taxing call sign N123QZ from apron to scenarios, A, B, C and D (8 marks)
   TABLE 2
   

   Scenario	Tower Instructions
   A	NOVEMBER 123QZ Runway 16, taxi via Alpha
   B	NOVEMBER 123QZ Runway 24, taxi via Alpha 2, Charlie and Bravo. Hold short runway 34.
   C	NOVEMBER 123QZ Runway 34, taxi via Alpha.
   D	NOVEMBER, 123QZ, line up and wait Runway 6, via Alpha and Bravo cross runway 6

2. List four facilities at the airport which guide the aircraft pilot during taxing (2 marks)
   Facilities
   1.      
   2.      
   3.         
   4.          

STATION 10

INSTRUCTIONS

Using the materials and tools provided, perform the following tasks:

1. Weigh parts labelled 'U'and V and record the weight (2 marks)
   Part 'U'
   Part 'V'
2.          
   1. Fill beaker labelled 'N' with water. Position the beaker on top of a stool Set the graduated cylinder labelled 'X' at the spout of the beaker Immerse part U' to the beaker 'W' Take and record the volume of water displaced by part U.
      Volume
   2. Repeat b(i) and with part 'V'. Take and record the volume of water displaced by part "V" (1 mark)
      Volume ...
3.                      
   1. Relate observations in a(i) and a(ii) (2½ marks)
      Relationship
   2. Relate observations in b(i) and b(ii).
      Relationship
   3. State the principle from the observations in a(i)(ii) and (i), (ii)
      Principle
   4. State two applications of the principle in theory of flight
      Applications 1. 
      Applications 2
4. Determine the lift of aircraft model labeled Z flying at 500 kph at sea level if the lift co-effficient is 0.87 (3½ marks)

MARKING SCHEME

STATION 1

Sketch  1 x 1 = 1 mark
Neatness 1 x 1 = 1 mark
Assembly 6 x 1 = 6 marks
Main parts 4 x ½= 2 marks

STATION 3

2.            
   1. Voltage 236 - 250v
   2. Voltage 236-250v
      (2 x ½= 1 mark)
3.             
   1. Voltage 236 - 250v
      (1 x ½)= ½ mark) (1 mark)
   2. The motor speed increases and bell ringing intensity increases
      (1 xl= 1 mark)
   3. The motor speed reduces and the bell ringing intensity decreases.
      (1 x 1=1 mark)
   4. Voltage - 110-120 volts
      (1 x ½= ½ mark) 
4.                       
   1. The power increases from 110-240 volts and thus the variation of motor.
      (1 x ½= 1 mark)
   2. Emergency audio warning. - Power step down for various components
      (2 x 1 = 2 marks) (2 marks)
5.               
   1. A-Switch
   2. B-AC step down transformer
   3. C-AC motor with level mechanism
   4. D-bell or gang
      (4 x ½=2 marks) (2 marks)

STATION 4

1.                  
   1. Bearing
   2. Tapered roller bearing
   3. To take both axial and radial loads
   4. Determine how much axial and radial load the bearing can sustain
      (4 x ½=2 marks)
2.        
   1. Sample Data
   2. Sample Data
   3. Sample Data
   4. Sample Data
   5. Sample Data
   6. Sample Data
      (6 x 1 = 6 marks)
3.              
   1. Excessive play of wear
   2. Corrosion
   3. Overheating
   4. Scratches or cracks
      (4 x ½= 2 marks)

STATION 5

1.                
   1. Torque Wrench
   2. Tightening the nuts and bolts to the torque to avoid over torqueing or under torqueing
   3. Calibration
   4. Ratchet
      (4 x ½= 2 marks) (2 marks)
2.                   
   1. Engine oil pump
   2. Spur gear type
   3. Lubrication system, Hydraulic system
      (3 x ½ = 1½ marks) (1% marks)
3.                  
   1. G-Pump Casing
      H Impeller gear
      J-Driver gear
      K-Idler shaft
      L Drive shaft
      (5 x ½ = 2½ marks) 
      
      
   2. White - Filling Port
      Blue - Locking
      (2 x ½=1 mark)
      
      
   3. G-Cracks and wear
      J Play on Spur gcar, wear, cracks etc.
      K-Play on driven impeller, gear wear
      L- Parallelism of the shaft and play.
      (4 x ½ mark)
      
      
4.                     
   1. Engine overheating
   2. High temperature indication
      (2 x ½ mark) (1 mark)

STATION 6

1. M-The instrument is marked A51 and readings are in knots and two ports
   N – The instrument reading are in PSI with range markings and one port.
   (2 x ½ =1 mark) 
2.          
   1. M-Pressure differential
      N Area differential
      (2 x ½=1 mark)
      
      
   2. M-Capsule
      N- Bourden tube
      (2 x ½=1 mark) 
      
      
   3. M-More sensitive to any changes
      N-Requires more forces to input changes
      (2 x ½ = 1 mark) 
      
      
   4.    
      

      Part	Function
      Pointer	to indicate reading
      Segmented gear	drive the points
      Drive pinion	To transmit motion from segmented gear to pointed
      Compensator	To allow for contraction and expansion
      Graduated scale	To show the information in connection with the

      (Any 4 x 1=4 marks) (4 marks)
   5. M-Navigation
      N- Engine
      (2 x ½= 1 mark) 
3.      
   1. Firmness of instrument
   2. Legibility of dial markings
   3. Presence of moisture inside the glass, which indicates a case leak.
      (2 x ½ = 1 mark) 

STATION 7

1.          
   1. Brake unit
   2. Single disc brake
   3. Landing gear brake system
   4. Ultra-light aircraft
      (4 x ½ =2 marks) 
2.               
   1. White - Cylinder head
      Blue - Piston
      Red - Linings
      Green -Gasket
      (4 x ½=2 marks)
   2.          
      1. Missing Piston Spring
      2. Linings worn out
      3. Seal cut
      4. Piston cylinder more scratched
         (4 x ½ = 2 marks) 
3.      
   1. Ensure the disc is not cracked or overheated
   2. Ensure no leakage is evident
   3. Ensure unit properly fitted and secured
   4. Ensure no brake binding or malfunction
      (4 x ½ = 2 marks) 

STATION 8

1.              
   1. Composite material
   2. Used where weight to strength ratio is necessary
      (2 x ½) = 1 mark)
      
      A Face Sheet
      B-Honey Comb Core
      
      A - Face sheet
      B-Honey comb corc
      (3 marks)
      Sketch - 1x 2 = 2 marks
      Labelling - 2 x ½ = 1 mark
2.                   
   1. Bolt
   2. The bolt head corners have slipped ends thus unserviceable for use on an aircraft
      (2 x ½=1 mark) 
      Correct sketch of a screw threads=2 marks
      Correct labelling of the thread = 2 marks
      Total = 4 marks

STATION 9

1.                    
   1.  Landing and taxing lights
   2. Follow me car
   3. Signs and
   4. Heading indicators
      (4 x ½=2 marks)

STATION 10

1.             
   1. Sample data
   2. Sample data
      (2 x 1 = 2 marks)
2.      
   1. Sample data
   2. Sample data
      (2 x 1= 2 marks)
3.                      
   1. Though past U and V are of the same size, the weight on the weighing scare is different. 
   2. V displace more water than U
   3. Archimedes Principle, a body in fluid displaces fluid equal to its weight
   4. Balloons
   5. Sea planes
      (5 x½ = 2½ marks)
4.         
   

   Data Given	Expected Response
   Span	Sample Data
   Chord	Sample data
   Density	1.225kgm3
   Velocity (v)	69.4 m/sec
   Formula	½ PV2 Scl
   Wing Area	Sample data
   Lift	Sample data

   (7 x ½= 3½ marks)