Figure 16-21. Steps in drawing the wind triangle.
90
80
70
60
50
40
30
20
10
170
160
150
140
130
120
110
100
Airspeed 120 knots
TC 090° GS 88
N33
30
W
24
21
S 15
12
E
6
3
P
W
E
N
S
90
80
70
60
50
40
30
20
10
170
160
150
140
130
120
110
100
90
80
70
60
50
40
30
20
10
170
160
150
140
130
120
110
100
W
E
N
S
TC 090°
Wind
Mid point
STEP 1
STEP 4
STEP 2 and 3
45°
90°
Step 2
With the ruler, draw the true course line from E, extending it
somewhat beyond the dot by 90°, and labeling it “TC 090°.”
Step 3
Next, align the ruler with E and the dot at 45°, and draw
the wind arrow from E, not toward 045°, but downwind in
the direction the wind is blowing making it 40 units long to
correspond with the wind velocity of 40 knots. Identify this
line as the wind line by placing the letter “W” at the end to
show the wind direction.
Step 4
Finally, measure 120 units on the ruler to represent the
airspeed, making a dot on the ruler at this point. The units
used may be of any convenient scale or value (such as ¼
inch = 10 knots), but once selected, the same scale must
be used for each of the linear movements involved. Then
place the ruler so that the end is on the arrowhead (W) and
the 120-knot dot intercepts the TC line. Draw the line and
label it “AS 120.” The point “P” placed at the intersection
represents the position of the aircraft at the end of 1 hour.
The diagram is now complete.
The distance flown in 1 hour (GS) is measured as the numbers
of units on the TC line (88 NMPH or 88 knots). The TH
necessary to offset drift is indicated by the direction of the
airspeed line, which can be determined in one of two ways:
• By placing the straight side of the protractor along
the north-south line, with its center point at the
intersection of the airspeed line and north-south line,
read the TH directly in degrees (076°). [Figure 16-22]
• By placing the straight side of the protractor along the
TC line, with its center at P, read the angle between
the TC and the airspeed line. This is the WCA, which
must be applied to the TC to obtain the TH. If the wind
blows from the right of TC, the angle is added; if from
the left, it is subtracted. In the example given, the
WCA is 14° and the wind is from the left; therefore,
subtract 14° from TC of 090°, making the TH 076°.
[Figure 16-23]
After obtaining the TH, apply the correction for magnetic
variation to obtain magnetic heading and the correction
for compass deviation to obtain a compass heading. The
compass heading can be used to fly to the destination by
dead reckoning.
To determine the time and fuel required for the flight, first
find the distance to your destination by measuring the length
of the course line drawn on the aeronautical chart (using the
appropriate scale at the bottom of the chart). If the distance
measures 220 NM, divide by the GS of 88 knots, which gives
2.5 hours, or 2:30, as the time required. If fuel consumption
is 8 gallons an hour, 8 × 2.5 or about 20 gallons is used.
Figure 16-23. Finding true heading by direct measurement.
90 80
70
60
50
40
30
20
10
170
160
150
140
130
120
110 100
TH 076° AS 120
TC 090° GS 88
P
W
E
N
S
90 80 70
10
20
150
140
130
120
110 100
14°
WCA =14° L
Figure 16-22. Finding true heading by the wind correction angle.
90
80
70
60
50
40
30
20
10
170
160
150
140
130
120
110
100
TH 076° AS 120
TC 090° GS 88
P
W
E
N
S
90
80
70
60
50
40
30
20
10
130
120
110
100
76°
Briefly summarized, the steps in obtaining flight information
are as follows:
• TC—direction of the line connecting two desired
points, drawn on the chart and measured clockwise
in degrees from TN on the mid-meridian
• WCA—determined from the wind triangle. (Added
to TC if the wind is from the right; subtracted if wind
is from the left)
• TH—direction measured in degrees clockwise from
TN, in which the nose of the plane should point to
remain on the desired course
• Variation—obtained from the isogonic line on the
chart (added to TH if west; subtracted if east)
• MH—an intermediate step in the conversion (obtained
by applying variation to TH)
• Deviation—obtained from the deviation card on the
aircraft (added to or subtracted from MH, as indicated)
• Compass heading—reading on the compass (found by
applying deviation to MH) that is followed to remain
on the desired course
Figure 16-24. Chart Supplement U.S. (formerly Airport/Facility
Directory).
• Total distance—obtained by measuring the length of
the TC line on the chart (using the scale at the bottom
of the chart)
• GS—obtained by measuring the length of the TC line
on the wind triangle (using the scale employed for
drawing the diagram)
• Estimated time en route (ETE)—total distance divided
by GS
• Fuel rate—predetermined gallons per hour used at
cruising speed
NOTE: Additional fuel for adequate reserve should be added
as a safety measure.
Flight Planning
Title 14 of the Code of Federal Regulations (14 CFR) part
91 states, in part, that before beginning a flight, the pilot in
command (PIC) of an aircraft shall become familiar with all
available information concerning that flight. For flights not
in the vicinity of an airport, this must include information
on available current weather reports and forecasts, fuel
requirements, alternatives available if the planned flight
cannot be completed, and any known traffic delays of which
the PIC has been advised by ATC.
Assembling Necessary Material
The pilot should collect the necessary material well before
beginning the flight. An appropriate current sectional chart
and charts for areas adjoining the flight route should be among
this material if the route of flight is near the border of a chart.
Additional equipment should include a flight computer or
electronic calculator, plotter, and any other item appropriate
to the particular flight. For example, if a night flight is to
be undertaken, carry a flashlight; if a flight is over desert
country, carry a supply of water and other necessities.
Weather Check
It is wise to check the weather before continuing with other
aspects of flight planning to see, first of all, if the flight is
feasible and, if it is, which route is best. Chapter 12, “Aviation
Weather Services,” discusses obtaining a weather briefing.
Use of Chart Supplement U.S. (formerly Airport/
Facility Directory)
Study available information about each airport at which a
landing is intended. This should include a study of the Notices
to Airmen (NOTAMs) and the Chart Supplement U.S.
(formerly Airport/Facility Directory). [Figure 16-24] This
includes location, elevation, runway and lighting facilities,
available services, availability of aeronautical advisory
station frequency (UNICOM), types of fuel available (use to
decide on refueling stops), FSS located on the airport, control
tower and ground control frequencies, traffic information,
remarks, and other pertinent information. The NOTAMs,
issued every 28 days, should be checked for additional
information on hazardous conditions or changes that have
been made since issuance of the Chart Supplement U.S.
The sectional chart bulletin subsection should be checked for
major changes that have occurred since the last publication date
of each sectional chart being used. Remember, the chart may
be up to 6 months old. The effective date of the chart appears
at the top of the front of the chart. The Chart Supplement U.S.
generally has the latest information pertaining to such matters
and should be used in preference to the information on the
back of the chart, if there are differences.
Airplane Flight Manual or Pilot’s Operating
Handbook (AFM/POH)
The Aircraft Flight Manual or Pilot’s Operating Handbook
(AFM/POH) should be checked to determine the proper
loading of the aircraft (weight and balance data). The weight
of the usable fuel and drainable oil aboard must be known.
Also, check the weight of the passengers, the weight of all
baggage to be carried, and the empty weight of the aircraft to
be sure that the total weight does not exceed the maximum
allowable weight. The distribution of the load must be known
to tell if the resulting center of gravity (CG) is within limits.
Be sure to use the latest weight and balance information in
the FAA-approved AFM or other permanent aircraft records,
as appropriate, to obtain empty weight and empty weight
CG information.
Determine the takeoff and landing distances from the
appropriate charts, based on the calculated load, elevation
of the airport, and temperature; then compare these distances
with the amount of runway available. Remember, the
heavier the load and the higher the elevation, temperature,
or humidity, the longer the takeoff roll and landing roll and
the lower the rate of climb.
Check the fuel consumption charts to determine the rate of
fuel consumption at the estimated flight altitude and power
settings. Calculate the rate of fuel consumption, and compare
it with the estimated time for the flight so that refueling points
along the route can be included in the plan.
Charting the Course
Once the weather has been checked and some preliminary
planning completed, it is time to chart the course and
determine the data needed to accomplish the flight. The
following sections provide a logical sequence to follow in
charting the course, complete a flight log, and filing a flight
plan. In the following example, a trip is planned based on the
following data and the sectional chart excerpt in Figure 16-25.
Route of flight: Chickasha Airport direct to Guthrie Airport
True airspeed (TAS)........................................115 knots
Winds aloft...........................................360° at 10 knots
Usable fuel.....................................................38 gallons
Fuel rate...............................................................8 GPH
Deviation..................................................................+2°
Steps in Charting the Course
The following is a suggested sequence for arriving at the
pertinent information for the trip. As information is determined,
it may be noted as illustrated in the example of a flight log in
Figure 16-26. Where calculations are required, the pilot may
use a mathematical formula or a manual or electronic flight
computer. If unfamiliar with the use of a manual or electronic
computer, it would be advantageous to read the operation
manual and work several practice problems at this point.
First, draw a line from Chickasha Airport (point A) directly
to Guthrie Airport (point F). The course line should begin at
the center of the airport of departure and end at the center of
the destination airport. If the route is direct, the course line
consists of a single straight line. If the route is not direct, it
consists of two or more straight line segments. For example, a
VOR station that is off the direct route, but makes navigating
easier, may be chosen (radio navigation is discussed later in
this chapter).
Appropriate checkpoints should be selected along the route
and noted in some way. These should be easy-to-locate
points, such as large towns, large lakes and rivers, or
combinations of recognizable points, such as towns with
an airport, towns with a network of highways, and railroads
entering and departing.
Normally, choose only towns indicated by splashes of yellow
on the chart. Do not choose towns represented by a small
circle—these may turn out to be only a half-dozen houses. (In
isolated areas, however, towns represented by a small circle
can be prominent checkpoints.) For this trip, four checkpoints
have been selected. Checkpoint 1 consists of a tower located
east of the course and can be further identified by the highway
and railroad track, which almost parallels the course at this
point. Checkpoint 2 is the obstruction just to the west of the
course and can be further identified by Will Rogers World
Airport, which is directly to the east. Checkpoint 3 is Wiley
Post Airport, which the aircraft should fly directly over.
Checkpoint 4 is a private, non-surfaced airport to the west of
the course and can be further identified by the railroad track
and highway to the east of the course.
The course and areas on either side of the planned route
should be checked to determine if there is any type of airspace
with which the pilot should be concerned or which has
special operational requirements. For this trip, it should be
noted that the course passes through a segment of the Class
C airspace surrounding Will Rogers World Airport where the
floor of the airspace is 2,500 feet mean sea level (MSL) and
the ceiling is 5,300 feet MSL (point B). Also, there is Class
D airspace from the surface to 3,800 feet MSL surrounding
Wiley Post Airport (point C) during the time the control
tower is in operation.
Study the terrain and obstructions along the route. This is
necessary to determine the highest and lowest elevations,
as well as the highest obstruction to be encountered so
an appropriate altitude that conforms to 14 CFR part 91
regulations can be selected. If the flight is to be flown
at an altitude of more than 3,000 feet above the terrain,
conformance to the cruising altitude appropriate to the
direction of flight is required. Check the route for particularly
rugged terrain so it can be avoided. Areas where a takeoff
or landing is made should be carefully checked for tall
obstructions. Television transmitting towers may extend to
altitudes over 1,500 feet above the surrounding terrain. It is
essential that pilots be aware of their presence and location.
For this trip, it should be noted that the tallest obstruction is
Figure 16-25. Sectional chart excerpt.
Checkpoint
Checkpoint
Checkpoint
Checkpoint
A
Class C AirspaceB
Class D AirspaceC
Tallest obstructionD
Highest elevation E
F
1
2
3
4
Route of flight: Chickasha Airport direct to Guthrie Airport
True airspeed (TAS) . . . . . . . . . . . . . . . . . . . . 115 knots
Winds aloft . . . . . . . . . . . . . . . . . . . . . . . 360° at 10 knots
Usable fuel . . . . . . . . . . . . . . . . . . . . . . . . . . . 38 gallons
Fuel rate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8 GPH
Deviation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . +2°
R
Course line
Figure 16-26. Pilot’s planning sheet and visual flight log.
PILOT’S PLANNING SHEET
COURSE TC TH MH DEV CH GS
From
To
From
To
WIND
Knots From
WCA
R+ L-
MAG VAR
W+ E-
TOTAL
MILES
TOTAL
TIME
FUEL
RATE
TOTAL
FUEL
PLANE IDENTIFICATION DATE
ALTITUDE
Chickasha
Guthrie 031° 10 360° 8000 3° L 28 7° E 21° +2° 23 53 106 kts 35 min 8 GPH 38 gal
N123DB
VISUAL FLIGHT LOG
WEATHER
AIRSPACE ETC.
POINT OF
DEPARTURE
Chickasha Airport
Guthrie Airport
TIME OF
DEPARTURE
DESTINATION
DISTANCE GSELAPSED TIMECOURSE CH REMARKS
NAVAID
IDENT.
FREQ.
NAVIGATION
AIDS
CHECKPOINT
#1
CHECKPOINT
#2
CHECKPOINT
#3
CHECKPOINT
#4
TO
FROM
TO
FROM
8000
10000
8000
10000
8000
10000
8000
10000
POINT TO POINTCUMULATIVE ACTUALESTIMATED
ACTUALESTIMATED ACTUALESTIMATED
11 NM
10 NM
10.5 NM
13 NM
8.5 NM
6 min
+5
6 min
6 min
7 min
5 min
106 kts
106 kts
106 kts
106 kts
023°
023°
023°
023°
21 NM
31.5 NM
44.5 NM
53 NM
ALTITUDE
part of a series of antennas with a height of 2,749 feet MSL
(point D). The highest elevation should be located in the
northeast quadrant and is 2,900 feet MSL (point E).
Since the wind is no factor and it is desirable and within the
aircraft’s capability to fly above the Class C and D airspace
to be encountered, an altitude of 5,500 feet MSL is chosen.
This altitude also gives adequate clearance of all obstructions,
as well as conforms to the 14 CFR part 91 requirement to
fly at an altitude of odd thousand plus 500 feet when on a
magnetic course between 0 and 179°.
Next, the pilot should measure the total distance of the
course, as well as the distance between checkpoints. The total
distance is 53 NM, and the distance between checkpoints is
as noted on the flight log in Figure 16-26.
After determining the distance, the TC should be measured.
If using a plotter, follow the directions on the plotter. The TC
is 031°. Once the TH is established, the pilot can determine
the compass heading. This is done by following the formula
given earlier in this chapter.
The formula is:
TC ± WCA = TH ± V = MH ± D = CH
The WCA can be determined by using a manual or electronic
flight computer. Using a wind of 360° at 10 knots, it is
determined the WCA is 3° left. This is subtracted from the
TC making the TH 28°. Next, the pilot should locate the
isogonic line closest to the route of the flight to determine
variation. Figure 16-25 shows the variation to be 6.30° E
(rounded to 7° E), which means it should be subtracted from
the TH, giving an MH of 21°. Next, add 2° to the MH for
the deviation correction. This gives the pilot the compass
heading of 23°.
Now, the GS can be determined. This is done using a manual
or electronic calculator. The GS is determined to be 106
knots. Based on this information, the total trip time, as well
as time between checkpoints, and the fuel burned can be
determined. These numbers can be calculated by using a
manual or electronic calculator.
Figure 16-27. Domestic flight plan form.
X
N123DB C150/X 115 CHK, CHICKASHA
AIRPORT 1400 5500
Chickasha direct Guthrie
GOK, Guthrie Airport
Guthrie, OK 35
4 45 1
Jane Smith
Aero Air, Oklahoma City, OK (405) 555-4149
Red/White
McAlester
For this trip, the GS is 106 knots and the total time is 35
minutes (30 minutes plus 5 minutes for climb) with a fuel
burn of 4.7 gallons. Refer to the flight log in Figure 16-26
for the time between checkpoints.
As the trip progresses, the pilot can note headings and time
and make adjustments in heading, GS, and time.
Filing a VFR Flight Plan
Filing a flight plan is not required by regulations; however, it
is a good operating practice since the information contained
in the flight plan can be used in search and rescue in the
event of an emergency.
Flight plans can be filed in the air by radio, but it is best to
file a flight plan by phone just before departing. After takeoff,
contact the FSS by radio and give them the takeoff time so
the flight plan can be activated.
When a VFR flight plan is filed, it is held by the FSS until
1 hour after the proposed departure time and then canceled
unless: the actual departure time is received; a revised
proposed departure time is received; or at the time of filing,
the FSS is informed that the proposed departure time is
met, but actual time cannot be given because of inadequate
communication. The FSS specialist who accepts the flight
plan does not inform the pilot of this procedure, however.
Figure 16-27 shows the flight plan form a pilot files with the
FSS. When filing a flight plan by telephone or radio, give
the information in the order of the numbered spaces. This
enables the FSS specialist to copy the information more
efficiently. Most of the fields are either self-explanatory
or non-applicable to the VFR flight plan (such as item 13).
However, some fields may need explanation.
• Item 3 is the aircraft type and special equipment. An
example would be C-150/X, which means the aircraft
has no transponder. A listing of special equipment
codes is found in the Aeronautical Information Manual
(AIM).
• Item 6 is the proposed departure time in UTC
(indicated by the “Z”).
• Item 7 is the cruising altitude. Normally, “VFR” can be
entered in this block since the pilot chooses a cruising
altitude to conform to FAA regulations.