15.19 powerplant installation Flashcards
where is the firewall?
between powerplant and aircraft
what is the firewall usually constructed from?
stainless steel
what is the typical format of an engine in terms of fire protection?
usually in zones for example
-fire zone
-flammable fluid leakage zone
-dry bay zone
categorised based on risk of flammable liquid or ignition
what separates engine zones?
basic structure or ancillary surfaces
what is a fire zone?
potential for ignition and flammable sources
what can helicopters have in addition to fire blankets?
fire sheet foam
what is the purpose of cowling?
protect from the operating environment and streamline as well as route cooling air effectively
what is the structure of cowlings?
easy access for maintenance usually fastening at 6 o clock underneath
what is contained in the c duct?
operating mechanisms for deployment of thrust reversers
how can c ducts be opened?
with an electrical or hand pump then held open with support rods
what must engine mounts be able to accommodate for?
temperature expansion in both radial and axial directions
what does a side mounted engine need?
front and rear saddle type beams attached through swinging links and thrust trunnions with a thrust strut connected to the airframe
what do forward engine mounts have to carry?
vertical side and axial loads
what is the typical engine mount structure?
spherical bearings for expansion sometimes with rubber bushings
where must wiring looms be routed?
in areas where they are not likely to be used as handholds
when contact with surounding structures cannot be avoided what must be done?
extra protection through grommets and chafe strips
when a wiring loom is routed over a hinge what must be ensured?
the wiring will twist instead of bend
what is the minimum bend radii for wires in groups?
not less than 10 x the diameter of the largest wire in their group
what can be the bend diameter at breakouts or reverse direction?
no more than 6 x the diameter
if there is no drain mast what can be employed instead?
a drain collector assembly
where is fluid or drain liquid collected from?
anywhere they may leak
