M15.19 Powerplant Installation Flashcards
What is the purpose of a firewall in an aircraft?
To isolate the powerplant from the airframe structure in case of fire and heat from engine operation
Firewalls are typically made from stainless steel or other high heat-resistant metals.
What materials are firewalls typically made from?
Sheet metal shields made from stainless steel or high heat-resistant metal
Firewalls protect the aircraft from fire hazards associated with the engine.
What is included in the term ‘powerplant’?
Engine, gearbox, fuel control, intake cowling, exhaust, thrust reverser assembly, fire protection equipment, sensors, generators, ducting, wiring, cowling, mounts, control cables and rods, drains
Everything associated with the engine on the engine side of the firewall.
What are the two common types of powerplant installations?
Wing-mounted and fuselage-mounted installations
Wing-mounted installations are common in air transport category aircraft, while fuselage-mounted designs are often used in business jets.
What does compartmentation in an engine pod refer to?
The classification of compartments as fire zones, flammable fluid leakage zones, or dry bay zones
This classification is based on the potential for ignition sources and flammable fluids.
What are the components of a typical engine pod classified as fire zones?
Engine case around the compressor, combustor, turbine sections, gearbox and accessories
These areas are potential ignition sources during failure conditions.
What is the function of engine cowls?
To protect the engine and its accessories from the operating environment and provide a streamlined, aerodynamic surface
Cowlings also route cooling air effectively around the engine.
When are thrust reverser cowls referred to as ‘C’ ducts?
When they contain the operating mechanisms for deployment of the thrust reverser and translating sleeves
‘C’ ducts include components like blocker doors and hydraulic actuators.
What is a disadvantage of using acoustic liners in engine design?
Increased weight and fuel consumption due to increased friction of duct walls
Acoustic liners are used to suppress noise from turbine engine operation.
What types of loads do forward engine mounts carry?
Vertical, side, and axial (thrust) loads
They also allow for engine growth due to thermal expansion.
What must be ensured when replacing or repairing a fuel line?
All fittings must be compatible with their mating parts
Improper fittings can lead to leaks or failures.
What should be done when replacing a flexible line?
Use the same type, size, part number, and length of hose as the line to be replaced
Avoid tight bends in flex lines to prevent failure.
Where must wire bundles be routed?
In accessible areas that are protected from damage and maintenance activity
They must not be used as handholds or support for personal equipment.
What is the function of control cables and rods in powerplant installations?
To activate accessories such as the fuel control unit
These components typically remain with the aircraft during engine changes.
What should be done when lifting turbine engines?
Use only the dedicated lifting points designed to safely lift the weight of the engine
Lifting from other locations can cause damage.
What are the main components of a drain system in powerplant installations?
Drain lines, module assembly, drain mast
These components collect and manage fluids during both malfunction and normal operation.
What is a typical area for fluid accumulation in an engine drain system?
Pylon, area of fuel-operated components, oil tank scupper, bearing sump seal drains
These areas are prone to leaks and fluid accumulation.
