Part 66 Preparation

15.7 Exhaust

Exhaust section impart a ---------- to the gases ?
1. High initial velocity
2. High final velocity
3. High final acceleration
Swirling exhaust gases leave the turbine at an angle of approximately ?
1. 45°
2. 40°
3. 48°
Thrust vectoring is used by ?
1. Commuter aircraft
2. Light sport aircraft
3. Military aircraft
The pilot can move, or vector, the vectoring nozzle up and down by ?
1. 22°
2. 21°
3. 20°
The advantage of a convergent-divergent nozzle is greatest at ?
1. High mach numbers
2. Low mach numbers
3. Below one mach
There are --------------- types of exhaust nozzle designs ?
1. One
2. Two
3. Three
The outer shell or duct of exhaust section is usually made of ?
1. Alloy steel
2. Stainless steel
3. Steel
Noise from turbulence of a coarser type portion has a much ?
1. High frequency
2. Fine frequency
3. Lower frequency
Which is the best source for reverse thrust ?
1. Fan
2. Turbo jet engine
3. Mechanical linkage
The fan air which creates most of the thrust ?
1. 75–85 percent total thrust
2. 80–85 percent total thrust
3. 80–88 percent total thrust

15.6 Turbine sections

Gas generator turbine is to absorb approximately ------ percent of the total pressure energy from the exhaust gases ?
1. 40-50
2. 60 to 70
3. 80-90
How many types of turbine are ?
1. Three
2. Two
3. Four
Most turbofan engines have ------?
1. Single stage turbine
2. Two spools
3. Single spool
Signs of -----on the turbine case may indicate the length of turbine blades is out of tolerance ?
1. Creep
2. Scoring
3. Deformation
Visible cracks may range in length from --------?
1. One-sixteenth inch downward
2. Five to ten inch
3. One-sixteenth inch upward
It increases with temperature and can result in observable dimensional changes to the blades ?
1. Deformation
2. Stress rupture cracks
3. Creep
It is caused by over-temperature and appear as waviness and/ or areas of varying airfoil thickness along the leading edge ?
1. Deformation
2. Stress rupture cracks
3. Creep
These usually appear as minute hairline cracks on or across the leading or trailing edge at a right angle to the edge length
1. Deformation
2. Creep
3. Stress rupture cracks
Which technique mostly used for Crack detection, when dealing with the turbine disk and blades ?
1. Ultrasonic
2. Eddy-current
3. Visual
The turbine shaft is usually fabricated from -------?
1. Alloy steel
2. Aluminium alloy
3. Cast iron

15.5 Combustion section

The major part of this energy developed during combustion process is required to drive,…..?
1. Fuel pump
2. To drive turbine
3. The compressor
This type of engine develop its 100 % thrust by accelrating the gasses out of the ?nozzle ?
1. Turbo jet
2. Turbo fan
3. Turboshaft
In the combustion chamber pressure and volume are…….?
1. Static pressure and volume remains constant
2. Static pressure decreases slightly and volume increases
3. Static pressure and volume decreases
Which component creates a vortex in a gas turbine flame tube ?
1. Swirl vanes
2. Tertiary holes
3. Louvers
The heat released by a combustion chamber is dependent on ?
1. Pressure of mixture
2. Pressure and speed of flame
3. Volume of the combustion area
Which air is used for combustion ?
1. Primary
2. Secondary
3. Primary and secondary
Modern Gas turbine engines usually have an ………?
1. Can-type combustion chamber
2. Annular combustion chamber
3. Can-annular type
Which type of fuel nozzle is required in the use of flow divider ?
1. Duplex nozzle
2. Simplex nozzle
3. Air blast simplex
Which type of combustion chamber is typicaly used on turbo shaft and Apu ?
1. Can-annular type
2. Annular type
3. Can-type combustion chamber
Combustion section is located between…………….. ?
1. Exhaust section and turbine section
2. Compressor and turbine
3. Exhaust and compressor

15.7 Exhaust