intro_to_aviation_block_2_20180401181925 Flashcards
What are the two ways piston engines are cooled
air cooled and liquid cooled
how do liquid cooled engines get cooled
circulate a liquid through the jackets of the pistons, then being sent back through a radiator to be cooled again
how do air cooled engines get cooled
allow airflow pushed by propellers and movement throug the air into the engine flowing by the cylinders, the air absorbs the heat and carries it away
what are the two common cylinder arragments in todays engines
radial and horizontally opposed
what is the shape of a radial engine
a circle with 5 7 or 9 pistons
what are the advantages of a radial engine
compact, accessible for maintnece and are light weight
what are the disadvantages of a radial engine
that they are poorly shaped, which leads to poor visibility and considerable drag
What are the advantages or a horizontally opposed engine
they have better visibility, have reduced drag
what are the disadvantages of a horizontally opposed engine
they have cooling problems if more then 6 cylinders, and there is increased drag from air scoops
what is the shape of a horizontally opposed engine
they have an even amount of cylinders that are set opposite from one another
what are the two types of Turbo engines
Turbo jet and turbo fan
Explain the workings of a turbo jet engine
-take air from outside- compass the air- force it into the combustion chamber- mix with fuel- ignite the fuel
What determines the amount of power the turbo jet engine produces
the weight of the air it consumes
Turbo jet RO
Air at lower altitudes is denser, so more fuel is required to produce the right Fuel to Air ratio. Engine power decreases with altitude because of this. However high altitude loss in engine power is offset by reduced aircraft friction to the surrounding air (DRAG). low altitude operations are no economical.
What are the advantages or a turbo jet engine
- few moving parts- good power to weight ratio - reduced drag
What are the disadvantages
they can become expensive with how excessive the amount of fuel is consumed at low altitudes.
Explain the workings of a Turbo Fan engine
Turbo fans are the new and improved version of the turbojet, this engine has a fan attached ahead of the compressor that accelerates air backwards and bypasses the core of the engine or behind the turbines . The outside diameter of the fan is greater then that of the engine proper so that the air, passing through the blades at their outer part, is accelerated backwards on the outside of the engine. This extra power/thrust is available for increase take off climb and cruise performance, reduced fuel consumption and hence better payload range
What is this engine desired for
High speed and high altitude usage, efficiency improves as the altitude increases. Prime efficiency is between 33 000 or 37 000 feet
What are some turbo fan advantages over the turbo jet
Greater fuel efficiency, quieter operation, better low altitude performance, and lower landing speeds
What are the disadvantages
Compared to a piston engine, they also have a high fuel consumption are low alritudes
Explain the workings of a turbo prop engine
contains properties of both a jet and prop plane, the gas turbine engine can be used to drive a propeller instead of producing pure jet power
how much of the power generated is used to power the turbine and how much is used for thrust
90-95% of the power goes to the turbine
Turbo Prop RO
- Engine efficiency improves with altitude (like Jet engines) the propeller efficacy drops off at higher altitudes do to the thin air. The propeller is more efficient in low speeds and altitudes where the air is denser. Generally they operate most efficiently in the range of 13 000 to 25 000
What is the advantages of a turbo prop
There is a greater horsepower for less weight when compared to a piston engine
What is the disadvantages
The propeller restricts the altitude as compared to the turbojet engines
for Piston engines, turbo prop engines and jet engines what is the Altitude
- piston- ground to 12000 feet- turboprop- 13000-25000 feet- Jet- 25 000 feet and up
for Piston engines, turbo prop engines and jet engines what is the Speed
- piston, up to 250 Knots - Turboprop, 200-300 knots- jet engine, 300-500 knots
for Piston engines, turbo prop engines and jet engines what is the Climb rate
- Piston - 500-1500 FPM- Turboprop - 1500-3000 FPM- Jet - 1500-6000 FPM
for Piston engines, turbo prop engines and jet engines what is the rate of descent
- Piston - 500-1500 FPM- Turboprop - 1500-4000 FPM- Jet - 200-6000 FPM
for Piston engines, turbo prop engines and jet engines what is the Rate of turns
- Piston - 1 (3 degrees per second/ 60 seconds for full turn)- Turboprop - 1 - Jet - .5 (twice the others)
for Piston engines, turbo prop engines and jet engines what is the Run-ups/ checks before departure
– Piston - Long- Turboprop - short- Jet - none
for Piston engines, turbo prop engines and jet engines what is the acceleration
- Piston - no delay- Turboprop - slight delay- Jet - long delay
for Piston engines, turbo prop engines and jet engines what is the Economy
- Piston - very efficient at low altitudes- Turboprop - efficient - Jet - less efficient
for Piston engines, turbo prop engines and jet engines what is the Foreign Object Damage
- Piston - doesn’t injest - Turboprop - doesn’t injuest - Jet - injests
What is a course pitch propeller
”" results in a more efficient cruising speed giving a greater distance per rotation
What is fine pitch propellar
”|” results in a smaller angle of attack, creating less drag and more power for better take off
What is a fixed pitch prop
when the prop is fixed at a angle by the manufacturer
What is adjustable variable pitch
propellers that can be changed pitch while on the ground
What is controllable variable pitch
these blades can be moved in flight
What is constant speed variable pitch
a variable pitch propeller fitted with a governor, this alters the blade angle to maintain a constant RPM for all conditions
Reversable Ptch
This is when the propellers are pushing air instead of pulling, switched around 180 degrees. nose wheel must be in contact with the ground before this is done
What is feathering
this is then the blade is like “—” this reduces drag and can be used when an engine fall is happening or when plane is parked to reduce wear on the parts from wind
What is mechanical blockage reversal system
a bucket type door is moved behind the thruster of the jet to deflect the gas ecahst infront of the plane pushing it backwards
what is Aeroymanic system
this causes the exhaust gas to get redirected outwards and forward through the thrust levers in the cock pit
Engine failure in a single engine aircraft
the plane has nowhere else to go but down, if this is after take off then it should continue going forward for obvious reason
Ailerons
these are movable control surfaces attached to the trailing edge of the wing, They move opposite to one another (one up the other down) this changes the lift characteristics of the airplane causing it to roll. They are controlled by turning the control column in the cockpit.
Elevators
Movable control surfaces attached to the trailing edge of the horizontal stabilizer. Unlike aileron, they move together. The are controlled by pushing and pulling the control column, when the column is pushed in the elevators are lowered and the nose pitches down. When the column is pulled the opposite occurs.
Rudders
Located on the tail, this movable surface of the vertical stabilizer that controls the aircrafts YAW. Rudder movement is controlled by moving the foot pedals in the control cockpit. Right pedal turns the plane right, the left pedal turns the plane left.
Trim Tabs
ocated on the trailing edge of the ailerons, elevators and rudders. They allow the pilot to maintain a constant altitude without applying constant pressure on the control column or rudder pedals. most cases it is controlled by turning a control wheel in the cockpit.
Flaps
on the trailing edge of the wing which are adjustable and change the shape of the wing. The purpose is to increase life (improve Take off and allows steeper angles of climb out and slower speeds during the approach phase) the three types of flap:- Lift, permits steeper climb out angle- Lift-drag, permits steep climb-out and slower approach- drag - permits slower approach
Speed Brakes/dive brakes
- found of few high performance aircraft. They are normally incorporated into the rear portion of the fuselage and consist of two hinged doors that extend into the air stream to create drag
Slats
Are Auxilary airfoils fitted into the leading edge of the wing, which are deployed either manually by pilot or automatically when the wing reaches a predetermined angle of attack
Slots
are passageways built into the wing often just behind the leading edge. Their purpose is to smooth out the flow of air over the top wing at high angles of attack
Spoilers
fitted into the top of the wing, “spoil” the airflow, this reduces lift, usually deployed after touch down during landing, often partially extended during flight to increase the rate of decent or reduce airspeed
Boudary layer control devices
most common is vortex generators, these small plates, stand in row along the wing and generate vortices during flight and improve the performance of the wing
What are the four types of landing gear
Wheels, skis, floats or amphibious