Climbing, Descending and Holding

Question 1

What is the definition of angle of attack, climb gradient, aircraft attitude, and rate of climb? DRAW

Answer 1

AoA: ANGLE between AIRCRAFT AXIS and AERODYNAMIC AXIS;
CLIMB GRADIENT: ANGLE between HORIZONTAL AXIS and AERODYNAMIC AXIS;
ATTITUDE: ANGLE between HORIZONTAL AXIS and AIRCRAFT AXIS;
RoC: VERTICAL COMPONENT of aircraft SPEED

Question 2

When is climb gradient at a maximum at a given weight and engine rating?

Answer 2

THRUST - DRAG is MAX ie: DRAG is MIN / BEST L/D / GREEN DOT / DRIFT DOWN SPEED;
BEST ALTITUDE for HORIZONTAL DISTANCE

Question 3

What is rate of climb at a maximum at a given weight?

Answer 3

TAS x (THRUST - DRAG) is MAX ie: Pthrust - Pdrag is MAX;
BEST ALTITUDE for TIME

Question 4

When increasing altitude, temperature, and weight, how does climb gradient and rate of climb change?

Answer 4

PA: BOTH DECREASE
TEMP: BOTH DECREASE
WEIGHT: BOTH DECREASE

Question 5

How does a headwind change rate of climb, fuel and time to top of climb, flight path angle, and ground distance to top of climb? DRAW

Answer 5

RoC and FUEL/TIME to ToC: CONSTANT;
FLIGHT PATH ANGLE: INCREASES;
GROUND DISTANCE to ToC: DECREASES

Question 6

What is the definition of a climb ceiling?

Why is it this value?

Answer 6

When RATE of CLIMB is EQUAL to 300ft/min;

Any MORE than this is both TIME and FUEL CONSUMING

Question 7

What are the 3 legal climb speed phases?

Answer 7

BELOW 10000ft: LIMITED to 250KIAS;
ABOVE 10000ft: ACCELERATES to MORE OPTIMUM SPEED but LIMITED to M0.78;
ABOVE CROSSOVER ALTITUDE: SPEED which AVOIDS HIGH SPEED BUFFETING

Question 8

What speed gives a maximum climb gradient?
What speed gives a maximum climb rate?
What speed gives a minimum climb cost?

Answer 8

GRADIENT: GREEN DOT;
RATE: Vy;
COST: 250kt/IAS econ/M econ

Question 9

What climb speed is optimum for when cost index is 0 and maximum?

Answer 9

CI = 0 (FUEL EXPENSIVE): Vy
CI = CI MAX (TIME EXPENSIVE): Mmo - 0.005M / Vmo - 10kt

Question 10

What is the cabin rate of climb limited to?

Answer 10

1000ft/min

Question 11

When is the descent gradient minimum for a given weight?

What advanatge does this give us?

Answer 11

With MINIMUM DRAG / MAX L/D / GREEN DOT;

MAX RANGE

Question 12

When is rate of descent minimum for a given weight?

What advantage does this give us?

Answer 12

TAS x DRAG is MINIMUM LESS than GREEN DOT;

MAX TIME

Question 13

How does a decrease in altitude and increase in temperature change descent gradient and rate of descent at a given weight and TAS?
Is this realistic?

Answer 13

In BOTH cases DENSITY INCREASES so DRAG INCREASES since GRADIENT and RATE are proportional to DRAG they will BOTH INCREASE;
It is INCONCLUSIVE as DESCENT is made at CONSTANT IAS or MACH NOT TAS

Question 14

How does an increase in weight change descent gradient and rate of descent

Answer 14

DECREASES BOTH due to L = W cos(DESCENT RATE)

Question 15

How does a headwind change rate of descent, fuel and time to top of descent, flight path angle, and ground distance to top of descent? DRAW

Answer 15

RoC and FUEL/TIME to ToD: CONSTANT;
FLIGHT PATH ANGLE: INCREASES;
GROUND DISTANCE to ToD: DECREASES

Question 16

How is descent at minimum gradient achieved?
How is descent at minimum rate achieved?
How is descent at minimum cost achieved?

Answer 16

GRADIENT: GREEN DOT;
RATE: LESS than GREEN DOT;
COST: MACH econ/IAS econ/250kt

Question 17

What descent speed is optimum for when cost index is 0 and maximum?

Answer 17

CI = 0 (FUEL EXPENSIVE): MIN DESCENT SPEED
CI = CI MAX (TIME EXPENSIVE): Mmo - 0.005M / Vmo - 10kt

Question 18

What is the procedure for an emergency descent?

Answer 18

Get to FL100 at MAX RATE of DESCENT;

DESCEND at Mmo or Vmo with EXTENDED AIR BRAKES if required

Question 19

How does the cabin descent work?

What are its rates of operation?

Answer 19

CALCULATES a CABIN DESCENT TIME at selected RATE so that CABIN PRESSURE reaches LANDING FIELD PRESSURE +0.1 psi just before landing;
DEFAULT DESCENT: 350ft/min;
MAX DESCENT: -750ft/min

Question 20

What happens if the cabin descent time is longer than the aeroplane descent time?
What can we use on a descent chart to determine whether this may happen at the given altitude?

Answer 20

Requires a REPRESSURISATION SEGMENT where aeroplane VERTICAL SPEED is LIMITED to permit CABIN REPRESSURISATION;
N1 THRUST is NOT SET to IDLE

Question 21

What is the optimum holding speed?

Answer 21

MIN FUEL CONSUMPTION: Between MIN DRAG SPEED and MAX L/D SPEED which are close meaning in CLEAN CONFIG SPEED is GREEN DOT

Question 22

When climbing at constant IAS, how do TAS and MACH change?

Answer 22

BOTH INCREASE

Question 23

When climbing at constant TAS, how do IAS and MACH change?

Answer 23

BOTH INCREASE

Question 24

When climbing at constant Mach, how do IAS and TAS change?

Answer 24

BOTH DECREASE