PERF

Question 1

Describe how thrust is produced by a turbine (jet) engine

Answer 1

Turbine engines produce thrust in four stages.
1. Intake
2. Compression
3. Combustion
4. Exhaust

Air is compressed, therefore temperature increases, fuel is injected which burns the air, creating a high pressure in the combustion chamber. The high pressure air rushes to low pressure atmosphere via the exhaust section.

Question 2

EPR

Answer 2

Engine Pressure Ratio (EPR) is the ratio of high pressure within the combustion chamber of a turbine engine to the ambient atmospheric pressure and is a measure of thrust.

The higher the EPR number, the higher the ratio, or difference between internal and external pressure, therefore the higher the thrust.

Question 3

Define V₁

Answer 3

Takeoff Decision Speed is the maximum speed during a takeoff roll at which the pilot may begin to reject a takeoff and the minimum speed during a takeoff roll in which the aircraft can reach the required height (35’) above the takeoff surface in the event of a takeoff.

Question 4

Define V_R

Answer 4

Rotation speed is the minimum speed during the takeoff roll at which the pilot may begin the rotation process.

Question 5

Define V₂

Answer 5

Takeoff Safety Speed is the speed at which the required one engine inoperative climb performance can be achieved for obstacle clearance purposes in the event of an engine failure during takeoff

Question 6

Define V_S

Answer 6

Stall speed

Question 7

Define V_SO

Answer 7

Stall speed in the landing configuration

Question 8

Define V_S1

Answer 8

Stall speed in a specified (by manufacturer) configuration

Question 9

Define V_C

Answer 9

Design cruising speed

Question 10

Define V_MO/M_MO

Answer 10

Maximum operating limit speed
V=KIAS
M=Mach number

Question 11

Define V_REF

Answer 11

Reference landing speed also known as approach speed

Question 12

Describe the four segments of climb and significance

Answer 12

Four segments of climb refer to the profile to be flown in the event of an engine failure during takeoff. Takeoff weight limited by one engine inop climb requirement based on these specs.

1.Liftoff to gear up,
2.Gear up to 400’ AGL (2.4% min climb gradient required)
3.400’ AGL, level to flaps up
4.Flaps up to 1,500’ AGL (1.4% min climb gradient required)

Question 13

Define takeoff distance

Answer 13

Takeoff distance is the manufacturer horizontal distance along from the start of the takeoff to the point at which the airplane is 35 feet above the takeoff surface.

§25.113 Takeoff distance

Question 14

Define accelerate-stop distance

Answer 14

Accelerate-stop distance is the distance necessary to accelerate an airplane from a standing start with all engines operating to the highest speed reached during a rejected takeoff, the pilot takes the first action to reject the takeoff at V1 for takeoff and come to a full stop.

§25.109 Accelerate-stop distance.

Question 15

Define takeoff run available (TORA)

Answer 15

** TORA** is the total length of runway available for an aircraft to accelerate from brake release to liftoff and half the horizontal distance to climb to 35 ft.

It is effectively, the actual length of a runway that an aircraft can use for a takeoff roll.

Question 16

Define takeoff distance available (TODA)

Answer 16

TODA is the distance available to accelerate from brake release, past lift-off, to the start of the takeoff climb.

TODA represents the entire distance that can be utilized for takeoff, including both runway and any clearway beyond the runway.

Question 17

Define accelerate-stop distance available (ASDA)

Answer 17

Accelerated-Stop Distance Available (TORA) is the total length of runway available (which may include a stopway) to accelerate from brake release to V1 plus the distance required to safely decelerate to a stop following a rejected takeoff.

Question 18

Define clearway

Answer 18

A clearway is an area beyond the runway free of permanent obstacles like buildings, trees, or terrain features.

Question 19

Define stopway

Answer 19

A stopway is an area beyond the runway specifically prepared to provide extra stopping distance for aircraft that cannot stop in the standard runway length due to a rejected takeoff or landing due to factors like a wet or contaminated surface on the runway, brake failure, or landing gear failure.

Key features of a stopway include:

-At least as wide as the runway
-Positioned on extended runway center line
-Able to support aircraft without causing structural damage

Question 20

How does runway slope affect takeoff and landing distance?

Answer 20

Uphill slope increases takeoff distance and decreases landing distance.

Downhill slope decreases takeoff distance and increases landing distance.

Question 21

Define driftdown method one and method two

Answer 21

Driftdown
Loss of altitude after an engine fails in flight.
Driftdown altitude
Manufacturer-published altitude at which the airplane can maintain after an engine fails in flight.

Determining maximum takeoff weight relative to driftdown:

Method one: weight which will result in driftdown altitude that complies with 1,000’ (2,000’ in mountainous area) obstacle clearance throughout flight.

Method two: flight is broken down into segments with specified alternates if an engine fails, which permits a higher takeoff weight than Method one.

Question 22

Define effective runway length (ERL)

Answer 22

Full published runway length minus displaced threshold (if any).

Question 23

How does use of anti icing bleed or pressurization bleed air affect turbine engine performance and allowable takeoff weight?

Answer 23

The use of bleed air will reduce engine thrust, and therefore, may reduce allowable takeoff weight.

Question 24

Is a jet more or less fuel efficient at high altitudes? Why?

Answer 24

More fuel efficient at high altitudes due to lower air density, which reduces airframe drag (assuming higher altitude doesn’t result in a higher headwind, which can reduce the efficiency by reducing ground speed, thereby increasing flight time.

Question 25

Define landing distance

Answer 25

Landing distance is manufacturer-published horizontal distance necessary to land and to come to a complete stop from a point 50 feet above the landing surface.

§25.125 Landing.

Question 26

Define landing distance available (LDA)

Answer 26

LDA is the available distance from the threshold to complete the approach, touchdown, and decelerate to a stop.

Question 27

Define displaced threshold

Answer 27

A displaced threshold is a threshold located at a point on the runway other than the designated beginning of the runway.

Displacement of a threshold reduces the length of runway available for landing.

Question 28

Describe the effect on turbine engine performance at a high elevation airport, high ambient temperature, and high relative humidity

Answer 28

Thrust will be reduced under any of these conditions due to lower air density. Lower air density means there are fewer air molecules available for compression and combustion. Lower air density may cause lower allowable takeoff weight as a result of lower thrust output.

Question 29

Define V_X

Answer 29

Speed for best angle of climb
Achieves greatest altitude over distance
FT/NM (feet per nautical mile)

Question 30

Define V_Y

Answer 30

Speed for best rate of climb.
Achieves greatest altitude over time
FPM (feet per minute)

Question 31

Define Maximum Takeoff Weight (MTOW)

Answer 31

The maximum takeoff weight for any given takeoff is the lowest of the following weight limits:

Maximum structural takeoff weight
Maximum structural landing weight
Maximum runway limited takeoff weight
Maximum runway limited landing weight
Maximum second segment limited weight
Maximum driftdown limited weight
Maximum takeoff or landing weight due to aircraft condition (CDL)

Question 32

Four segments of climb (engine inop)

Answer 32