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Pilot's Handbook of Aeronautical Knowledge
Aircraft Performance
Performance Charts

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Pilot's Handbook of Aeronautical Knowledge

Preface

Acknowledgements

Table of Contents

Chapter 1, Introduction To Flying
Chapter 2, Aircraft Structure
Chapter 3, Principles of Flight
Chapter 4, Aerodynamics of Flight
Chapter 5, Flight Controls
Chapter 6, Aircraft Systems
Chapter 7, Flight Instruments
Chapter 8, Flight Manuals and Other Documents
Chapter 9, Weight and Balance
Chapter 10, Aircraft Performance
Chapter 11, Weather Theory
Chapter 12, Aviation Weather Services
Chapter 13, Airport Operation
Chapter 14, Airspace
Chapter 15, Navigation
Chapter 16, Aeromedical Factors
Chapter 17, Aeronautical Decision Making

Appendix

Glossary

Index

Sample Problem 4
Departing Airport Pressure Altitude.................6,000 feet
Departing Airport OAT............................................25 °C
Cruise Pressure Altitude..................................10,000 feet
Cruise OAT..............................................................10 °C

First, find the information for the departing airport. Find the
OAT for the departing airport along the bottom, left-hand side
of the graph. Follow the line from 25 °C straight up until it
intersects the line corresponding to the pressure altitude of
6,000 feet. Continue this line straight across until it intersects
all three lines for fuel, time, and distance. Draw a line straight
down from the intersection of altitude and fuel, altitude and
time, and a third line at altitude and distance. It should read
three and one-half gallons of fuel, 6.5 minutes of time, and
nine NM. Next, repeat the steps to find the information for
the cruise altitude. It should read six and one-half gallons
of fuel, 11.5 minutes of time, and 15 NM. Take each set of
numbers for fuel, time, and distance and subtract them from
one another (6.5 – 3.5 = 3 gallons of fuel). It will take three
gallons of fuel and 5 minutes of time to climb to 10,000
feet. During that climb, the distance covered is six NM.

Remember, according to the notes at the top of the chart, these
numbers do not take into account wind, and it is assumed
maximum continuous power is being used.

The next example is a fuel, time, and distance-to-climb table.
For this table, use the same basic criteria as for the previous
chart. However, it is necessary to figure the information in a
different manner. Refer to Figure 10-25 to work the following
sample problem.

Sample Problem 5
Departing Airport Pressure Altitude..................Sea level
Departing Airport OAT............................................22 °C
Cruise Pressure Altitude....................................8,000 feet
Takeoff Weight.............................................3,400 pounds

To begin, find the given weight of 3,400 in the first column of
the chart. Move across to the pressure altitude column to find
the sea level altitude numbers. At sea level, the numbers read
zero. Next, read the line that corresponds with the cruising
altitude of 8,000 feet. Normally, a pilot would subtract these
two sets of number from one another, but given the fact that
the numbers read zero at sea level, it is known that the time
to climb from sea level to 8,000 feet is 10 minutes. It is also
known that 21 pounds of fuel will be used and 20 NM will be
covered during the climb. However, the temperature is 22 °C,
which is 7° above the standard temperature of 15 °C. The notes
section of this chart indicate that the findings must be increased
by ten percent for each 7° above standard. Multiply the findings
by ten percent or (10 x .10) = 1, 1 + 10 = 11 minutes. After
accounting for the additional ten percent, the findings should
read 11 minutes, 23.1 pounds of fuel, and 22 NM. Notice that
the fuel is reported in pounds of fuel, not gallons. Aviation fuel
weighs six pounds per gallon, so 23.1 pounds of fuel is equal
to 3.85 gallons of fuel (23.1 ÷ 6 = 3.85).

Fuel time distance climb.
Figure 10-25. Fuel time distance climb.

The next example is a cruise and range performance chart.
This type of table is designed to give TAS, fuel consumption,
endurance in hours, and range in miles at specific cruise
configurations. Use Figure 10-26 to determine the cruise and
range performance under the given conditions.

Sample Problem 6
Pressure Altitude...............................................5,000 feet
RPM..................................................................2,400 rpm
Fuel Carrying Capacity..................38 gallons, no reserve

Find 5,000 feet pressure altitude in the first column on the
left-hand side of the table. Next, find the correct rpm of 2,400
in the second column. Follow that line straight across and
read the TAS of 116 mph, and a fuel burn rate of 6.9 gallons
per hour. As per the example, the aircraft is equipped with
a fuel carrying capacity of 38 gallons. Under this column,
read that the endurance in hours is 5.5 hours and the range
in miles is 635 miles.

 

10-22