Post on 19-Dec-2015
transcript
Predicting Performance
Density Altitude
• Pressure altitude corrected for nonstandard temperature
Density Altitude
• High
• Hot
• Humid
Density Altitude
• Common methods of calculating include:
• Flight computer
• Density Altitude Chart
Density Altitude• Moisture - effects not shown on
performance charts
• High Humidity - engine horsepower reduction of 7%
• Takeoff and Climb performance 10%
Surface Winds
• Headwind or tailwind component–a 10 knot headwind might improve
performance by 10%
–a 10 knot tailwind might degrade performance by 40%
Surface Winds
• Crosswind component
• Demonstrated crosswind component
Runway Conditions• Gradient
–greater than .3% it will be listed in A/FD
• Braking Effectiveness–good, fair, poor, and nil
• Hydroplaning
Hydroplaning
• Dynamic Hydroplaning
• = X 8.6
• = 30 X 8.6 = 47 Kts
PSI
POH
• Prior to 1979 Owners Manual varied in content and format
Determine the density altitude for these conditions
Altimeter Setting……………30.35
Runway Temperature………+25oF
Airport Elevation……3,894 ft MSL
2,000 feet
The surface wind is 180° at 30 knots.
What is the crosswind component for a RWY 15 landing.
• 15 knots
The surface wind is 180° at 20 knots.
What is the headwind component for a RWY 12 landing.
• 10 Knots
Performance Charts
• Experience Test Pilots
• Factory new Airplanes
• Repeated Tests using Best Results
• Format -Table -Graphic
Takeoff Charts
• Ground Roll
• Distance to clear a 50 foot barrier
Rate of Climb
• Takeoff power
• Maximum continuous power–Temperature
–Pressure Altitude
–Airplane Weight
Rate of Climb
• Provide information on time, fuel and distance required to climb from one altitude to another
• Subtract values from starting altitude
Cruise Charts
• Range is the distance an airplane can travel with a given amount of fuel
• Endurance is the length of time the airplane can remain in the air
Cruise Charts
• Maximum range is at L/Dmax or best glide speed
• Maximum endurance is about 76% or best glide speed
• Generally close to stall speed
Descent Charts• Not found for most aircraft
• Often overlooked by pilots
• As you start flying higher and faster, you must start planning your descents farther from the intended point of landing
Glide Charts
• With GPS and the ability to have navigation data to the nearest airfield with the touch of a button, you should be able to mentally calculate if you can glide to the nearest airfield
Stall Speeds
• As angle of bank increases, stall speed increases
• As flap deflection is increased, stall speed decreases
Landing Charts
• Ground roll
• Over a 50 foot obstacle