Chapter 5.3 - Engine Controls & Handling Flashcards
Name the three main Engine Controls?
- Throttle.
- Mixture Control.
- Carburettor Heat Control.
Name five in-flight Engine Operations with limitations?
- Engine Speed (RPM).
- Oil Temperature and Pressure.
- Cylinder Head Temperature.
- Fuel-air Mixture Setting.
- Fuel Pressure.
Why is there a ‘Maximum RPM’ limit?
To ensure the Engine will not be overstressed and damaged.
Why is there a Minimum/Maximum Oil Temperature limit?
- Below Minimum Oil range will be too cold and thick to provide adequate lubrication.
- Above Maximum Oil range the Engine will overheat and cause damage.
Why is there a ‘Minimum Oil Pressure’ limit?
To ensure there is enough Oil feeding to the Engine.
Why is there a Minimum/Maximum CHT?
To avoid damage to the Cylinders of an Engine.
What does MC stand for?
Maximum Continuous.
Define MC Power?
Maximum power that can be maintained continuously by an Engine.
Name two measurements power output of an Engine?
- Kilowatts (kW).
- Brake Horsepower (BHP).
The pressure in the Induction Manifold varies according to which two factors?
- Throttle Settings.
- Atmospheric Pressure.
To maintain a Constant Engine Speed as height is increased, the Throttle must be what?
Opened Progressively.
Name 4 different characteristics which can affect an Engine’s Power Output?
- Size and Design of Engine.
- Condition of the Engine.
- The Valve.
- Ignition Timing.
Atmospheric Density can affect what setting?
Fuel-air Mixture Setting.
How should the Throttle be moved?
With smooth and positive action.
What’s the quickest the Throttle should be opened from closed?
1 second (one and two).
What happens if a Pilot moves the Throttle too quickly?
Can overstress the Engine.
What is the Best Power Mixture?
Slightly Richer than CCM.
The Carburettor is designed to give the best power fuel-air mixture at sea-level on a standard day. However, with higher temperatures and Altitude, the fuel-air mixture can become richer than normal. How can a pilot amend this?
With the use of Manual Mixture Control, to enable a Pilot to lean the mixture.
Under conditions of decreased density what happens to the fuel-air mixture?
Becomes richer.
An extremely Over-Lean mixture can cause an outcome leading to what?
Fuel Starvation and eventually the Engine will stop.
An Over-Lean mixture may be indicated by the Engine doing what?
Backfiring.
Name three consequences of having an Over-Rich mixture?
- Rough running of the Engine.
- Fouled Spark Plugs.
- High Fuel Consumption.
An Over-Rich mixture is indicated by what?
Black-smoke from the Exhaust.
What is Detonation?
Premature explosive burning of the fuel-air charge in the Cylinders.
How does Detonation occur (2)?
- Temperature and/or Pressure is too high.
- Fuel has lower than specified Octane Rating.
How can a Pilot detect Detonation in the Engine?
Loud ‘pinging’ sound and rough running of the Engine.
What can Detonation lead to?
Loss of Engine Power, which can result in, Engine Failure.
True or False. The lower the Octane Rating, the better the anti-detonation property?
False.
If Detonation is suspect, what should a Pilot aim to do?
Reduce the combustion temperature.
How can a Pilot reduce Detonation (3)?
- Enriching the Mixture.
- Carburettor is Off.
- Reduce Power.
True or False. Increasing Air Speed can assist with treating Detonation?
True. Increasing Air Speed can help cool the Engine.
The best way to avoid Detonation at high power settings is to do what (2)?
- Mixture is always Rich.
- Correct Grade of Fuel is used.
True or False. Pre-Ignition is like Detonation?
True.
Name two functions of the Mixture Control?
- Leaning Fuel for Economic Cruising.
- Stopping the Engine.
At what percentage of MC power is the Mixture Control used to Lean the Fuel-air mixture?
Below 75%.
Name two examples of decreased density conditions, where Leaning the Fuel-air Mixture is appropriate?
- Climbs above 5000ft.
- Operations at High Altitude Airports.
How does a Pilot lean the Fuel-air Mixture for Cruise?
Move the mixture control until Engine Speed Peaks (before Engine runs rough).
All takeoffs should be made with the Mixture Control in what position?
Full Rich.
What factor of Engine handling should a Pilot be wary of when commencing a descent?
Preventing the Engine from getting too cold.
At what position should the Mixture control be during descent?
Enriched progressively or set as fully rich position.
When descending through a prolong glide, the Engine should be warmed periodically, for every 1000ft of descent. What percentage of MC power should be used?
50-60%
Name 4 reasons why an Engine should be kept warm during descent on a glide?
- Clear Engine of any Carbon.
- Ensure Engine is responsive when power is needed.
- Keep Oil at its correct temperature.
- Reduce the risk of Carburettor Icing.
Severe Carburettor Icing appears at mild temperatures with high humidity? What is the degree Celsius and humidity level for Carburettor Icing?
- 16°C.
- Above 50% Humidity.
Carburettor Icing can also form at low power settings, particularly during which stage of flight?
Part or Closed Throttle Descent.
What is the first indication of Carburettor Icing on Aircraft’s with fixed-pitch propellers?
Gradual reduction in RPM at constant throttle.
When is Throttle Ice more likely to occur?
At low power settings during part-throttle descent.
How does Impact Ice occur (2)?
- Outside temperature below freezing (0°C to -25°C).
- Visible moisture in the form of Cloud.
True or False. Impact Ice can occur during VFR flight and why?
False. Under VFR Pilot are not allowed to fly through clouds.
How is the air heated before reaching the Carburettor Heat Control?
The air is heated around the Exhaust Manifold.
The Carburettor Head Control is used for preventing and removing what?
Ice build-up.
When Ice is suspected in an aircraft, what should a Pilot do and what affect will this have (2)?
- Apply Full Carburettor Heat.
- Further decrease in RPM.
If no Ice is present, what changes will be made to the RPM, until the Carburettor Heat is turned off?
No further change in RPM.
If Ice is present and Carburettor Heat is set as ‘On’, what will happen to the RPM?
Increase as Ice is removed.
To prevent icing on descent what should a Pilot do?
Set Carburettor Heat Control to Full Heat.
To maximise the amount of heated air from the exhaust when should Carburettor Heat be switched ON?
Before the Throttle is closed.
What does CAT stand for?
Carburettor Air Temperature.
What is the optimum Carburettor Air Temperature?
25°C – 30°C.
True or False. Carburettor Heat decreases Engine performance?
True.
Why should Carburettor Heat not be used when full-power is required?
It may increase the operating temperature of the Engine and even cause Detonation.
What happens to Engine performance when Carburettor Heat is ‘On’?
Reduces the power output (RPM).
How can the loss of power generated from Carburettor Heat being ‘On’ affect the Aircraft (2)?
- Reduce Rate of Climb.
- Decrease Airspeed.
What are the three main factors causing power reduction from Carburettor Heat being ‘On’ during full-power?
- Decrease in air density.
- Over-rich Mixture.
- Loss of Ram air pressure.
Carburettor Heat should be set as what before Landing and why (2)?
- OFF.
- In case extra power is needed to perform a ‘Go-Around’.
If severe icing conditions are suspected on ground, when should a Pilot use Carburettor Heat (2)?
- Pre-takeoff Ground Check.
- During Taxiing.
Safety Precaution for Start-up: What should a Pilot call when starting the Propeller?
Clear Propeller.
Safety Precaution for Start-up: Why should a Pilot never re-engage the starter while the Propeller is still turning?
This can damage the Starter Motor.
Safety Precaution for Start-up: How long should a Pilot engage the Starter Motor and why (2)?
- Short periods only.
- To avoid overheating the Starter Motor and Battery.
Safety Precaution for Start-up: When starting a cold Engine, what mark reading on the Tachometer should not be exceeded after the first minute of operation?
1000 RPM.
Safety Precaution for Start-up: If the Oil Pressure doesn’t not register within the first 30 seconds of starting, what should a Pilot do?
Stop the Engine.
A significant part of the Engine warm-up occurs at which stage of flight?
Taxiing.
How does a Pilot check if the Carburettor Heat Control is working?
Apply full Carburettor Heat at 1500-1600 RPM, there will be a 150 RPM decrease on the Tachometer to show the control is working.
If there are signs of rough Engine operation and/or sluggish acceleration at high RPM, with Mixture in full rich and Carburettor Heat ‘Off’ during the early part of Takeoff. What should a Pilot do?
Abandon Takeoff.
Safety Precaution for Pre-Takeoff: Why should a Pilot not operate for more than 10-15 seconds on a single Magneto?
This can cause Spark Plug Fouling.
Safety Precaution for Pre-Takeoff: All Takeoffs should be made with the Carburettor Heat Control set as?
OFF (Cold).
The use of Carburettor Heat should not be used above which power setting?
75% or above MC.
Preventing Engine Overheating during Ground Operations: What position should the Aircraft be facing?
Into-wind.
Preventing Engine Overheating during Ground Operations: Conduct all ground operations with the Mixture Control in which position?
Full Rich.
Preventing Engine Overheating during Ground Operations: True or False. An Aircraft should never exceed the maximum specified ground RPM?
True.
Preventing Engine Overheating during Ground Operations: Why should a Pilot avoid prolonged idling out of wind?
Prolonged idling will cause Spark Plug Fouling.
