Aerospace Materials Questions and Answers Part-5

1. Which of the following can be used to make seats in an aircraft?
a) Magnesium alloy sheets
b) Graphite
c) Rubber
d) Pure magnesium

Answer: a
Explanation: Aircraft seats are made using magnesium alloy sheets. Aluminium alloy sheets can also be used. Pure magnesium is not used, as alloyed metals typically have preferable properties compared to elements in their pure state.

2. Metals like chrome-molybdenum steel are heated to a temperature of ____________ to make bushings.
a) 500 or 750 psi
b) 1000 psi
c) 650,000 or 7000,000 psi
d) 125,000 or 150,000 psi

Answer: d
Explanation: Bushings are manufactured by heating metals like chrome-molybdenum steel to a temperature of 125,000 or 150,000 psi. Bushings can be replaced by new parts once they are worn out.

3. Wood cannot be used to make any part of an aircraft.
a) True
b) False

Answer: b
Explanation: Wood is used in manufacturing several parts of an aircraft. It is used in propeller blades, wing ribs etc. Plywood is used in making parts like wing leading edge, flooring, etc. Wing beams can be made of several types of woods like Douglas fir, poplar etc.

4. Bolts in an aircraft are made of _____________
a) nickel steel
b) graphite
c) aluminium
d) iron

Answer: a
Explanation: Nickel steels are used in making bolts of an aircraft. Bolts are used in structural connections. Bolts made of nickel steel have higher Strength compared to chrome-molybdenum bolts, which are used if there is a requirement of welding as nickel steel is not easy to weld.

5. Which of the following is not used to manufacture a wing-tip bow?
a) Chrome-molybdenum
b) Aluminium alloy
c) Douglas fir
d) Mild steel

Answer: c
Explanation: Wing-tip bows can be manufactured using chrome-molybdenum, aluminium alloy and mild steel. However, Douglas fir is not used. Douglas fir is a type of tree whose wood can be used in manufacturing wing beams.

6. What are the wheels of a landing great made of?
a) Typical rubber
b) Sensitive rubber
c) Titanium alloy
d) Thick rubber

Answer: d
Explanation: The wheels of landing gear are made of thick rubber. This is to absorb any shocks. The other part of the landing gear contains titanium alloys. The wheels are pumped with gases like nitrogen to avoid explosions.

7. Which of the following specification is used in manufacturing fuselage, oil tank and wings of an aircraft?
a) 1111-Z
b) 2024-T4
c) 2011-X2
d) 1214-A

Answer: b
Explanation: 2024-T4 is used in manufacturing several components of an aircraft like the fuselage, oil tank and wings. It is used in wing covering, wing ribs, wing leading edge, wing beams, etc. 2024-T4 is a type of aluminium alloy. It is a part of the 2000 series of aluminium alloy.

8. Which of the following components is/are used in making aircraft wings?
a) Titanium alloys
b) Graphite
c) Aluminium alloys
d) Titanium alloys and aluminium alloys

Answer: a
Explanation: Both titanium alloys and aluminium alloys can be used in making aircraft wings. Titanium alloys have good strength, low weight and are resistant to corrosion. Aluminium alloys have high strength and high ductility.

9. Non-metallic materials are primarily used in manufacturing _____________
a) fuselage
b) engine
c) wing tips and stabilizer tips
d) seats

Answer: c
Explanation: There are several non-metallic parts used in the construction of an aircraft. Wing tips and stabilizer tips contain non-metallic parts. The different non-metallic parts used are transparent plastics, reinforced plastics, carbon fiber materials, etc.

10. What is the variation to which the tension testing machine must be sensitive?
a) 1/250 of the registered load
b) 1/100 of registered load
c) 1/500 of registered load
d) 1/200 of the registered load

Answer: a
Explanation: To obtain an accurate result, it is important for the test machine to be in appropriate condition. One of the important conditions is for a load being applied, the test machine must be sensitive to a variation of 1/250.