15.19 powerplant installation

Question 1

where is the firewall?

Answer 1

between powerplant and aircraft

Question 2

what is the firewall usually constructed from?

Answer 2

stainless steel

Question 3

what is the typical format of an engine in terms of fire protection?

Answer 3

usually in zones for example
-fire zone
-flammable fluid leakage zone
-dry bay zone
categorised based on risk of flammable liquid or ignition

Question 4

what separates engine zones?

Answer 4

basic structure or ancillary surfaces

Question 5

what is a fire zone?

Answer 5

potential for ignition and flammable sources

Question 6

what can helicopters have in addition to fire blankets?

Answer 6

fire sheet foam

Question 7

what is the purpose of cowling?

Answer 7

protect from the operating environment and streamline as well as route cooling air effectively

Question 8

what is the structure of cowlings?

Answer 8

easy access for maintenance usually fastening at 6 o clock underneath

Question 9

what is contained in the c duct?

Answer 9

operating mechanisms for deployment of thrust reversers

Question 10

how can c ducts be opened?

Answer 10

with an electrical or hand pump then held open with support rods

Question 11

what must engine mounts be able to accommodate for?

Answer 11

temperature expansion in both radial and axial directions

Question 12

what does a side mounted engine need?

Answer 12

front and rear saddle type beams attached through swinging links and thrust trunnions with a thrust strut connected to the airframe

Question 13

what do forward engine mounts have to carry?

Answer 13

vertical side and axial loads

Question 14

what is the typical engine mount structure?

Answer 14

spherical bearings for expansion sometimes with rubber bushings

Question 15

where must wiring looms be routed?

Answer 15

in areas where they are not likely to be used as handholds

Question 16

when contact with surounding structures cannot be avoided what must be done?

Answer 16

extra protection through grommets and chafe strips

Question 17

when a wiring loom is routed over a hinge what must be ensured?

Answer 17

the wiring will twist instead of bend

Question 18

what is the minimum bend radii for wires in groups?

Answer 18

not less than 10 x the diameter of the largest wire in their group

Question 19

what can be the bend diameter at breakouts or reverse direction?

Answer 19

no more than 6 x the diameter

Question 20

if there is no drain mast what can be employed instead?

Answer 20

a drain collector assembly

Question 21

where is fluid or drain liquid collected from?

Answer 21

anywhere they may leak