Contents:

(资料图)

Factors of Aircraft Performance

Factors of Takeoff and Landing Performance

Calculating Takeoff and Landing Performance

Factors of Climb Performance

Calculating Climb Performance

Factors of Cruise Performance

Calculating Cruise Performance

1. Factors of Aircraft Performance

Aircraft Performance   

Determine:

How much runway you need for takeoff

Whether you can safely clear obstacles on departure

The amount of fuel you need

How much runway you need for landing

Table Performance Chart

Graph Performance Chart

Interpolation

Round out for more conservative figures

Effects of Air Density

Reduced air density = reduced aircraft performance

Longer takeoff roll

Dimished propeller efficiency

Variables that decrease air density:

Low pressure

High temperature

High humidity

Density Altitude

Pressure altitude: Altitude corrected for nonstandard pressure

Density altitude: Pressure altitude corrected for nonstandard temperature

At standard temperature, pressure altitude = density altitude

When the actual temperature exceeds the standard temperature, the density altitude can be substantially higher than the field elevation; aircraft performs as though they were at the higher elevation

Effects of Density Altitude

High, hot and humid = high density altitude

Calculating Density Altitude

Find the pressure altitude correcting for nonstandard pressure

Subtract the conversion factor from the field elevation to determine the pressure altitude

Locate the temperature at bottom of the chart and move up until you intercept the diagonal pressure altitude line

Move left and find the density altitude 

2. Factors of Takeoff and Landing Performance

Aircraft Weight

Aircraft Flap Configuration

Takeoff - greater lift

Landing - reduced approach speed, steepened glide path, and lower touchdown speed

Headwind Component

Reduce takeoff ground roll

Shorten the landing roll

Tailwind Component

Much more takeoff distance

A 9 knots headwind reduces the takeoff distance by 10 percent

A 9 knots tailwind increases the takeoff distance by 45%

Smaller effects on landing distance

Crosswind Component

Depends on its net wind

Determining Headwind and Tailwind Components

Runway Gradient

Usually expressed as a percent

Positive gradient is unfavorable for takeoff

Positive gradient is favorable for landing

Negative gradiant decreases takeoff distance

Negative gradient increases landing distance

Runway Surface

Performance data is based a paved, level runway with a smooth, dry surface

Adjust the takeoff and landing distances for any other runway surface

3. Calculating Takeoff and Landing Performance

Takeoff Performance Table

Takeoff Performance Graph

Landing Performance Table

Landing Performance Graph

4. Factors of Climb Performance

Climb Airspeeds:

Best angle-of-climb (Vx) 

Used for obstacle clearance immediately after takeoff

Provides the greatest altitude gain in the shrtest distance

Best rate-of-climb (Vy)

Used when aircraft has cleared all obstacles after takeoff

Provides the greatest altitude gain in a given time

Cruise climb airspeed 

Generally higher than Vx or Vy

Better engine cooling

Better forward visibility

Better forward speed (reduced time enroute)

Absolute Ceiling and Service Ceiling

As altitude increases:

Vy increases

Vy decreases

Absolute ceiling is:

Where Vx and Vy meet

The point beyond which the aircraft cannot climb

Service ceiling is:

The altitude beyond which an aircraft can climb no more than one hundred feet per minute

5. Calculating Climb Performance

Climb Performance Table

Climb Performance Graph

6. Factors of Cruise Performance

Cruise performance charts enable you to predict:

Rate of fuel consumption

True airspeed

Range

Endurance

Trade-offs include:

Time 

Power

Fuel consumption

Speed

Range

Three Main Cruise Airspeeds

Maximum level flight airspeed

Occurs when the force of total drag equals the force of full thrust

Further acceleration in level flight is not possible even with full power

Maximum range airspeed

Enables you fly the greatest distance per gallon of fuel

Produces minimum total drag and the highest lift to drag ratio

Maximum endurance airspeed

Enables the aircraft to remain aloft for the longest period of time

Achieves the minimum fuel use per hour

7. Calculating Cruise Performance

Cruise Power Setting Table

Best Power Mixture Range Graph

Setting Engine Performance Table

Cruising True Airspeed Graph