Propeller ! Flashcards
(26 cards)
auxiliary systems
prevent or remove ice formations from an aircraft
Ice formations
can distort a propeller blade’s airfoil shape causing a loss in propeller efficiency and thrust
anti-icing system
prevents the formation of ice
ice form unevenly on propeller
produces propeller unbalance and destructive vibration
de-icing system
removes ice after it has accumulated
icing protection
it is necessary when the aircraft is flying under icing
conditions
two main methods icing protection
Fluid anti-icing system
Electrical de-icing system
Fluid Anti-Icing System
using an alcohol based liquid
very simple and problem-free method to prevent ice formation
Fluid anti-ice system consists
- control unit
- tank that holds a quantity of anti-icing fluid
- pump to deliver the fluid to the propeller
- nozzles
rheostat
is adjusted to control the pump output.
is contained in the control unit
slinger ring
As fluid passes through the nozzle, it enters a circular U-shaped channel
stationary nuzzle
Fluid is pumped from the tank to a _______ ________ installed just behind the propeller on the engine nose case
delivery tube
A typical slinger ring is designed with a ______ _____ for each propeller blade and is mounted on the rear of the propeller assembly.
centrifugal force
It sends the anti-icing fluid out through the delivery tubes to each blade shank
Feed shoes
are typically installed on the leading edge of each propeller blade
isopropyl alcohol
The most commonly used anti-icing fluid
phosphate compounds
Anti-icing fluids made from _____ ______ also have the
advantage of reduced flammability, they are comparatively expensive
Resistance heating elements may be mounted either
internally or externally on each propeller blade
ELECTRIC DE-ICE SYSTEM
electrically operated
ELECTRIC DE-ICE SYSTEM
- power source
- power relay
- resistance heating elements
- system controls
- timer or cycling unit
brush blocks
are mounted on the engine case
deicing boots
are attached to each blade with an approved bonding agent
Externally mounted heating elements
slip rings
are mounted on the back of the propeller hub assembly
Runback
melted ice reforms behind a blade’s leading edge
