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Figure 36
(Refer to figure 36.) What is the expected fuel consumption for a
1,000-nautical mile flight under the following conditions?
Pressure altitude
. . . . . . . . . . . . . . . . . . . . . . . . . 8,000 ft
Temperature
. . . . . . . . . . . . . . . . . . . . . . . . . 22°C
Manifold pressure
. . . . . . . . . . . . . . . . . . . . . . . . . 20.8" Hg
Wind
. . . . . . . . . . . . . . . . . . . . . . . . . Calm
ANSWER: 70.1 gallons.
To determine the fuel consumption,
you need to know the number of hours the flight will last
and the gallons per hour the airplane will use. The chart is
divided into three sections. They differ based on air
temperature. Use the right section of the chart as the
temperature at 8,000 ft. is 22°C.
At a pressure altitude of 8,000 ft., 20.8" Hg manifold
pressure, and 22°C, the fuel flow is 11.5 GPH and the true
airspeed is 164 kt. Given a calm wind, the 1,000-NM trip will
take 6.09 hr. (1,000 NM ÷ 164 kt).
6.09 hr. x 11.5 GPH = 70.1 gal.
Figure 36
(Refer to figure 36.) What is the expected fuel consumption for a
500-nautical mile flight under the following conditions?
Pressure altitude
. . . . . . . . . . . . . . . . . . . . . . . . . 4,000 ft
Temperature
. . . . . . . . . . . . . . . . . . . . . . . . . +29°C
Manifold pressure
. . . . . . . . . . . . . . . . . . . . . . . . . 21.3" Hg
Wind
. . . . . . . . . . . . . . . . . . . . . . . . . Calm
ANSWER: 36.1 gallons.
At 4,000 ft., 21.3" Hg manifold
pressure, and 29°C (use the section on the right), the fuel
flow will be 11.5 GPH, and the true airspeed will be 159 kt.
The 500-NM trip will take 3.14 hr. (500 NM ÷ 159 kt).
3.14 hr. x 11.5 GPH = 36.1 gal.
Figure 36
(Refer to figure 36.) Determine the approximate manifold pressure
setting with 2,450 RPM to achieve 65 percent maximum continuous
power at 6,500 feet with a temperature of 36°F higher than standard.
ANSWER: 21.0" Hg.
The part of the chart on the right is for
temperatures 36°F greater than standard. At 6,500 ft. with a
temperature of 36°F higher than standard, the required
manifold pressure change is 1/4 of the difference between
the 21.0" Hg at 6,000 ft. and the 20.8" Hg at 8,000 ft., or
slightly less than 21.0. Thus, 21.0 is the best answer given.
The manifold pressure is closer to 21.0 than 20.8.
Figure 36
(Refer to figure 36.) Approximately what true airspeed should a
pilot expect with 65 percent maximum continuous power at 9,500
feet with a temperature of 36°F below standard?
ANSWER: 183 MPH.
The left part of the chart applies to
36°F below standard. At 8,000 ft., TAS is 181 MPH. At
10,000 ft., TAS is 184 MPH. At 9,500 ft., with a temperature
36°F below standard, the expected true airspeed is 75%
above the 181 MPH at 8,000 ft. toward the 184 MPH at 10,000
ft., i.e., approximately 183 MPH.
Figure 37
(Refer to figure 37.) What is the crosswind component for a landing
on Runway 18 if the tower reports the wind as 220° at 30 knots?
ANSWER: 19 knots.
The requirement is the crosswind
component, which is found on the horizontal axis of the
graph. You are given a 30-kt. wind speed (the wind speed is
shown on the circular lines or arcs). First, calculate the angle
between the wind and the runway (220° - 180° = 40°). Next,
find the intersection of the 40° line and the 30-kt. headwind
arc. Then, proceed downward to determine a crosswind
component of 19 kt.
Note the crosswind component is on the horizontal axis and
the headwind component is on the vertical axis.
Figure 37
(Refer to figure 37.) What is the headwind component for a landing
on Runway 18 if the tower reports the wind as 220° at 30 knots?
ANSWER: 23 knots.
The headwind component is on the
vertical axis (left-hand side of the graph). Find the same
intersection as in the preceding question, i.e., the 30-kt. wind
speed arc, and the 40° angle between wind direction and
flight path (220° - 180°). Then move horizontally to the left
and read approximately 23 kt.
Figure 37
(Refer to figure 37.) Determine the maximum wind velocity for a 45°
crosswind if the maximum crosswind component for the airplane is
25 knots.
ANSWER: 35 knots.
Start on the bottom of the graph's
horizontal axis at 25 kt. and move straight upward to the 45°
angle between wind direction and flight path line (half-way
between the 40° and 50° lines). Note that you are half-way
between the 30 and 40 arc-shaped wind speed lines, which
means that the maximum wind velocity for a 45° crosswind is
35 kt. if the airplane is limited to a 25-kt. crosswind
component.
Figure 37
(Refer to figure 37.) With a reported wind of north at 20 knots,
which runway (6, 29, or 32) is acceptable for use for an airplane
with a 13-knot maximum crosswind component?
ANSWER: Runway 32.
If the wind is from the north (i.e.,
either 360° or 0°) at 20 kt., runway 32, i.e., 320°, would
provide a 40° crosswind component (360° - 320°). Given a
20-kt. wind, find the intersection between the 20-kt. arc and
the angle between wind direction and the flight path of 40°.
Dropping straight downward to the horizontal axis gives 13
kt., which is the maximum crosswind component of the
example airplane.
Figure 37
(Refer to figure 37.) What is the maximum wind velocity for a 30°
crosswind if the maximum crosswind component for the airplane is
12 knots?
ANSWER: 24 knots.
Start on the graph's horizontal axis at
12 kt. and move upward to the 30° angle between wind
direction and flight path line. Note that you are almost
half-way between the 20 and 30 arc-shaped wind speed
lines, which means that the maximum wind velocity for a 30°
crosswind is approximately 24 kt. if the airplane is limited to a
12-kt. crosswind component.
Figure 37
(Refer to figure 37.) With a reported wind of south at 20 knots,
which runway (10, 14, or 24) is appropriate for an airplane with a
13-knot maximum crosswind component?
ANSWER: Runway 14.
If the wind is from the south at 20 kt.,
runway 14, i.e., 140°, would provide a 40° crosswind
component (180° - 140°). Given a 20-kt. wind, find the
intersection between the 20-kt. arc and the angle between
wind direction and the flight path of 40°. Dropping straight
downward to the horizontal axis gives 13 kt., which is the
maximum crosswind component of the example airplane.
Figure 38
(Refer to figure 38.) Determine the total distance required to land.
OAT
. . . . . . . . . . . . . . . . . . . . . . . . . . Std
Pressure altitude
. . . . . . . . . . . . . . . . . . . . . . . . . . 10,000 ft
Weight
. . . . . . . . . . . . . . . . . . . . . . . . . . 2,400 lb
Wind component
. . . . . . . . . . . . . . . . . . . . . . . . . . Calm
Obstacle
. . . . . . . . . . . . . . . . . . . . . . . . . . 50 ft.
ANSWER: 1,925 feet.
The landing distance graphs are very
similar to the takeoff distance graphs. Begin with the
pressure altitude line of 10,000 ft. and the intersection with
the standard temperature line which begins at 20°C and
slopes up and to the left; i.e., standard temperature
decreases as pressure altitude increases. Then move
horizontally to the right to the first reference line. Proceed
parallel to the closest guideline to 2,400 lb. Proceed
horizontally to the right to the second reference line. Since
the wind is calm, proceed horizontally to the third reference
line. Given a 50-ft. obstacle, proceed parallel to the closest
guideline to the right margin to determine a distance of
approximately 1,900 ft.
Figure 38
(Refer to figure 38.) Determine the approximate total distance
required to land over a 50-ft. obstacle.
OAT
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90°F
Pressure altitude
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4,000 ft
Weight
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2,800 lb
Headwind component
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 kts
ANSWER: 1,775 feet.
To determine the total landing
distance, begin at the left side of Fig. 38 on the 4,000-ft.
pressure altitude line at the intersection of 90°F. Proceed
horizontally to the right to the first reference line. Proceed
parallel to the closest guideline to 2,800 lb., and then straight
across to the second reference line. Since the headwind
component is 10 kt., proceed parallel to the closest headwind
guideline to the 10-kt. line. Then move directly to the right,
to the third reference line. Given a 50-ft. obstacle, proceed
parallel to the closest guideline for obstacles to find the total
distance of approximately 1,775 ft.
Figure 38
(Refer to figure 38.) Determine the total distance required to land.
OAT
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90°F
Pressure altitude
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3,000 ft
Weight
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2,900 lb
Headwind component
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 kts
Obstacle
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50 ft
ANSWER: 1,725 feet.
To determine the total landing
distance, begin with pressure altitude of 3,000 ft. (between
the 2,000- and 4,000-ft. lines) at its intersection with 90°F.
Proceed horizontally to the right to the first reference line,
and then parallel to the closest guideline to 2,900 lb. From
that point, proceed horizontally to the second reference line.
Since there is a headwind component of 10 kt., proceed
parallel to the closest headwind guideline down to 10 kt. and
then horizontally to the right to the third reference line.
Given a 50-ft. obstacle, proceed parallel to the closest
guideline for obstacles to find the landing distance of
approximately 1,725 ft.
Figure 38
(Refer to figure 38.) Determine the total distance required to land.
OAT
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32°F
Pressure altitude
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8,000 ft
Weight
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2,600 lb
Headwind component
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 kts
Obstacle
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50 ft
ANSWER: 1,400 feet.
To determine the total landing
distance, begin with the pressure altitude of 8,000 ft. at its
intersection with 32°F (0°C). Proceed horizontally to the first
reference line, and then parallel to the closest guideline to
2,600 lb. From that point, proceed horizontally to the second
reference line. Since there is a headwind component of 20 kt.,
follow parallel to the closest headwind guideline down to 20
kt., and then horizontally to the right to the third reference
line. Given a 50-ft. obstacle, proceed parallel to the closest
guideline for obstacles to find the landing distance of
approximately 1,400 ft.
Figure 39
(Refer to figure 39.) Determine the approximate landing ground roll
distance.
Pressure altitude
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . Sea level
Headwind
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 kts
Temperature
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . Std
ANSWER: 401 feet.
At sea level, the ground roll is 445 ft.
The standard temperature needs no adjustment. According
to Note 1 in Fig. 39, the distance should be decreased 10%
for each 4 kt. of headwind, so the headwind of 4 kt. means
that the landing distance is reduced by 10%. The result is
401 ft. (445 ft. x 90%).
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