Controls and Handling Flashcards
How does the throttle work?
Controls the throttle valve.
This means more or less air ( therefore fuel as the fuel is sucked in )
Types of fuel pumps and purposes
Engine driven -
Electric - start up and critical phase of flight
What does alternative Air do?
(and what are the 2 differences between the normal one? )
Provide a different air source for the engine
This is preheated and not filtered.
What is the fuel priming pump?
How does it work?
Risks of use?
Manually pump fuel into the lines.
Send fuel to the cylinder NOT the carb
If it is not closed properly can result in too rich of a mixture.
What is the manifold gauge ( measures) ?
Used in variable pitch propellor.
Measures the Actual Pressure in the intake manifold
Kinda like an engine power guage
decreases with altitude
Max is atmospheric pressure ( unless turbo charging )
If fixed pitch. Manifold pressure and RPM rise and fall together.
RPM is the PROP RPM.
At full open throttle - it should match the altitmeter setting.
Where is manifold pressure measured?
On the air intake, after the throttle valve
What does RPM measure?
Crankshaft rotations.
How is Oil Temp measured?
Electrically
How is oil pressure measured?
Pressure sent to guage,
Restriction to protect from surges
How is Cylinder Head Temp measured?
thermo couple on the hottest cylinder
How is EGT measured?
thermo coupling in the exhuast pipe.
type of carb ice?
Throttle Ice - use carb heat
Fuel evaporation ice - use carb heat
Impact Ice - use alternative air. ( should not happen in VFR )
Describe Throttle Ice
Lower pressure and reduce temp after the venturi results in ice on the throttle Butterfly valve
Fix - Carb Heat
Describe Fuel Evaporation ice
Low pressure causes fuel to evaoprate, lowering the temp.
Results in ice build up on the intake manifold.
Fix - Carb Heat
When is carb icing (throttle and fuel) is likely to occur
When the temp is at 20 degrees or below and high humidity.
Describe impact ice
ice forming on the air intake.
Should not happen in VRF
Fix - alternative air.
Carb heat - when to use - what to expect?
Rough running engine.
Temp is 20 degrees or below
High relative humidy
If Ice was present - Engine RPM will go DOWN and then UP
If ice was not present - Engine RPM will go DOWN
If you increase throttle to increase power, when you have carb ice, what happens?
The icing gets worse. More fuel = more Throttle Butterfly Icing or Fuel Evaporation icing.
When should you use carb heat preventively
Read your POH
Idle descents - carb heat ON during descent.
Carb heat OFF before full power
What are the construction factors that contribute to engine power?
- Number of cylinders
- Compression ratio. Higher is better.
- Displacement - volume between BDC and TDC
What is the compression ratio, and at what level does it stop increasing power?
The ratio of the volume when the piston is at TDC vs BDC.
Anything more than 10:1 is leads to detonation and pre-ignitation.
What 8 the possible causes of rough engine running?
- Out of balance prop
- Loose prop
- Not enough fuel
- Incorrect Mixture
- Ignition fault
- Resonance - indicated on RPM gauge in yellow
- Carb ice
- Carb heat on
When should you use warm/alt air?
(And when should you not use it)
- When you suspect impact icing
- RPM will go DOWN
- Don’t use on the ground ( no filter )
- Avoid continous use. Can lead to Cylinder head overheat
What do you do with low oil pressure, and what are the likely causes?
Cross check. Low pressure without increase in oil temp, may mean a instrument problem
Low oil pressure with high oil temp, indicates a potential engine problem.
Divert
If pressure keeps dropping, consider precautionary.
Causes:
- leak
How soon should the oil pressure rise on startup?
within 30 seconds.
If it does not, shut down
High Oil pressure, causes and risks
Causes
- Possible blocked relief value
- Possible blocked something else
- Pump will be workinghard.
Actions
- Reduce power.
- If pressure comes down, continue flight.
- If pressure does not come down ,divert
Fluctuating oil pressure
Causes
- Faulty instrument
- Caviation.
Low oil temp in flight, causes and actions?
Causes
- Oil is too thick.
- Oil Pump will be working harder
Actions
- Cross Check - should have elevated pressure
- Continue to monitor.
High oil temp, causes and actions?
Causes
- Not enough oil
- Could be a leak or blocker line/oil cooler
Actions
- High cylinder head temp esp. at low airspeed and high RPM. Lower nose, open cowl flaps
Caution
Increasing oil temp is usually the first signal of a loss of oil.
Oil pressure will stay constant, until it drops fast - if there is a leak.
