Weight Balance / Landing Performance

Question 1

What is the Max T.O.W

Weight related

Answer 1

Maximum Take off Weight
Never to be exceeded.
Legal requirement.

Question 2

What is the Z.F.W ( Zero Fuel Weight)?

Answer 2

Basic Empty Weight + Payload

Question 3

What is the R.W( Ramp Weight)?

Answer 3

Z.F.W + Fuel

Question 4

What is the landing Weight?

Answer 4

T.O.W - Trip Fuel

Question 5

What are:
Basic Weight
Variable Weight
Dry Operating Weight
Payload Weight

Answer 5

Basic = Fixed Equipment + Oil + Unusable fuel
Variable = Crew + Crew Gear + Supplies
Dry Operating Weight = Basic + Variable
Payload Weight = Passengers + Luggage + Freight NOT Fuel

Question 6

Conversaion Factor - AVGAS Litres to KG
AND
US Gallons to Litres

Answer 6

0.72
3.78

Question 7

ISA Hpa and temp?

Answer 7

1013 and
15 degrees C
At MSL

Question 8

Calculate Pressure Altitude

Answer 8

1013 - QNH = diff
diff * 27

Question 9

Impacts on Pressure and temp for ISA variations

Answer 9

Pressure: 1 hpa = 27ft
Temp: 2 degrees = 1,000
Temp variation = 1 deg in difference = 120 ft.

Question 10

Calculate density Altitude

Answer 10

• Calc expected ISA Temp at the Altitude
  2 * (Altitude / 1000)
• Calculate difference in actual temp from ISA
• Multiple difference by 120
• Add result to Pressure Altitude

Question 11

Group ratings for Aircraft and runways

Answer 11

If the aircraft group is <= runway group, landing calcs are not required.

Question 12

Legal take off and landing

Answer 12

Total distance available assume aircraft at 50 ft at threshold.

Question 13

Propellor
What is the Blade Angle?
What is the blade twist ( and why )?

Answer 13

Blade angle, angle between rotation plane and chord of the prop.
Blade twist - to keep the AoA consistant along the blade.

Question 14

Fixed pitch prop
What is the most efficent AoA for the blade?
How does efficencty of the prop change compared to airspeed?

Answer 14

AoA - 2 - 4 degress
The shape of a fix pitch prop has a peak efficiency. This means different props for different purposes. E.G Short field performance would have less AoA to give more Thrust at lower airspeeds.

Question 15

What happens to Airflow and AoA when a prop speed increases?

Answer 15

Increasing speed results in a high angle of attack.
Which increases Torque
Which increases airflow
And therefore then decreases AoA ( not back to where it was )

Question 16

REQUIRED
What is Total Reaction Force for a propellor?

Answer 16

Thrust + Prop Torque

Prop Torque is resistance to motion in the plane of rotation and it is equal and opposite to engine torque

Question 17

How does a constant speed prop work?

Answer 17

Today - CSU ( Constant speed unit ) will adjust prop angle to keep RPM constant.
Power is controlled by Throttle
Prop Speed by Pitch Control

Question 18

Constant Speed Prop
What order does power/pitch need to be adjusted and why?

Answer 18

There is a risk of overspeeding either the engine OR the prop
Takeoff
Prop is fine (full forward).
Power needs to be managed

Cruise
Throttle First
Then Pitch back ( to coasre )

Approach to Land
Throttle decrease
Wait for speed to come down
Prop control, slowly toward fine.