Chapter 4 ( Installation And Ground Running) Flashcards
What is required when a gas turbine engine is installed in an aircraft?
A number of accessories fitting and connections to various aircraft systems must be made. The engine, jet pipe, and accessories must be suitably cowled, and an air intake must be provided for the compressor.
How is engine identification done on multi-engine aircraft?
The left (port) engine is No 1 and the right (stbd.) engine is No 2 when looking at the aircraft from the rear.
What is the designation for a single engine aircraft?
The engine is always known as No 1.
What are the two ways an engine can be referred to?
- The Engine: consists of the engine without any supporting accessories. 2. The Engine Change Unit (ECU): consists of the engine plus its supporting accessories.
What checks are performed for pre-installation?
Log Cards, Modification State, Checklist (using the aircraft parts catalogue), and Removed ECU checks.
What checks are carried out before post-installation ground runs?
Independent Inspections, Loose Article check, Fuel flow, Tool control, MoD F700 Aircraft āSā to Ground Run.
How are turbo shaft engines installed into airframes?
They are installed via engine mounts and engine attachments.
What must be done during the removal of an ECU?
Many pipes will be disconnected, and blanks must be fitted to all orifices to prevent foreign objects, dirt, and moisture from entering the systems.
What factors determine the mounts employed in an installation?
The mounts employed will depend on the design of the installation; in general, they will be vibration absorbing.
What can result from the deterioration of vibration absorbing material?
Deterioration of the vibration absorbing material can lead to mis-alignment of the engine.
How is the engine typically mounted during start?
It is normal for the engine to be mounted on fixed and moveable mounts as it expands during start.
How is the front of the engine attached in helicopters?
In helicopters, the front of the engine is attached to the transmission and support is taken from the cold front part of the engine.
What is the purpose of a thrust bar or twin engine mount?
A thrust bar or a twin engine mount is often employed to absorb the torque reaction between the engine and the airframe.
What does the forward mount connect to?
The engine front mounting is attached with the reduction gearbox to the air-intake-case hub.
What is the function of the gimbal ring in the forward mount?
The gimbal ring connects the engine front mounting and the aircraft main rotor gearbox support-assembly and includes four spherical bearings.
What does the rear mount consist of?
The engine rear mounting includes two link plates attached to a lug on the bottom of the engine interstage case.
How does the rear mount facilitate engine removal and installation?
The mounting permits a small movement in a longitudinal direction during the engine removal and installation.
What is Lateral Restraint?
Lateral Restraint (Side Stay) holds the engine laterally with a side stay attached between the outboard lug on the engine inter-stage case and a lug on a support attached to the engine bay deck. Each lug contains a spherical bearing.
What is a Vibration Mount?
A Vibration Mount usually carries the vertical weight of the engine. As the rubber material deteriorates, the alignment of the engine can be affected, resulting in rapid deterioration of the fixed mounting spherical bearings.
What are Lifting Points?
Lifting Points are fitted on all engines as part of the main structure and are located at the centre of balance point.
What should be done before lifting an engine?
Before lifting, examine the lifting points on the ECU, carry out a Pre-use check on the lifting tackle, ensure the lifting beam is of the correct type, and observe all safety procedures, including wearing hard hats and not standing under a suspended load.
