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时间:2010-05-30 14:03来源:蓝天飞行翻译 作者:admin
曝光台 注意防骗 网曝天猫店富美金盛家居专营店坑蒙拐骗欺诈消费者

Fuel burned during descent and landing ............... 1,350 lbs
Determine the weight at the end of cruise by using the Gross
Weight Table of Figure 6-4 and following these steps:
1. Use the U.S. Standard Atmosphere Table in Figure 6-5
to determine the standard temperature for 16,000. This
is -16.7°C.
2. The ambient temperature is -32°C, which is a deviation
from standard of 15.3°C. (-32° – -16.7° = 15.3°). It is
below standard.
3. In Figure 6-4, follow the vertical line representing 140,000
pounds gross weight upward until it intersects the diagonal
line for 16,000 feet pressure altitude.
4. From this intersection, draw a horizontal line to the left
to the temperature deviation index (0°C deviation).
5. Draw a diagonal line parallel to the dashed lines for
“Below Standard” from the intersection of the horizontal
line and the Temperature Deviation Index.
6. Draw a vertical line upward from the 15.3°C Temperature
Deviation From Standard.
7. Draw a horizontal line to the left from the intersection of
the “Below Standard” diagonal and the 15.3°C
temperature deviation vertical line. This line crosses the
“Fuel Flow—100 Pounds per Hour per Engine” index at
11.35. This indicates that each of the four engines burns
1,135 (100? 11.35) pounds of fuel per hour. The total fuel
burn for the 4-hour cruise is:
8. The airplane gross weight was 140,000 pounds at takeoff,
and since 18,160 pounds of fuel was burned during cruise
and 1,350 pounds was burned during the approach and
landing phase, the landing weight is:
140,000 – (18,160 + 1,350) = 120,490 pounds
Maximum zero fuel weight: The
maximum authorized weight of an
aircraft without fuel. This is the sum
of the BOW and payload.
Payload: The weight of the
passengers, baggage, and cargo that
produces revenue.
6 – 11
Figure 6-4. Gross weight table.
6 – 12
Figure 6-5. Standard atmosphere table.
Determining the Minutes
of Fuel Dump Time
Most large aircraft are approved for a greater weight for
takeoff than for landing, and to make it possible for them to
return to landing soon after takeoff, a fuel jettison system
is sometimes installed.
It is important in an emergency situation that the flight crew
be able to dump enough fuel to lower the weight to its allowed
landing weight. This is done by timing the dumping process.
In this example, the aircraft has three engines operating and
these specifications apply:
Cruise weight ...................................................... 171,000 lbs
Maximum landing weight .................................. 142,500 lbs
Time from start of dump to landing ................... 19 minutes
Average fuel flow
during dumping and descent ................ 3,170 lb/hr/eng
Fuel dump rate .............................. 2,300 pounds per minute
Follow these steps to determine the number of minutes of
fuel dump time:
1. Determine the amount the weight of the aircraft must be
reduced to reach the maximum allowable landing weight:
171,000 lbs cruise weight
– 142,500 lbs maximum landing weight
28,500 lbs required reduction
2. Determine the amount of fuel burned from the beginning
of the dump to touchdown:
Fuel jettison system: A fuel subsystem
that allows the dumping of
fuel in an emergency to lower the
weight of an aircraft to the maximum
landing weight. This system must
allow enough fuel to be jettisoned that
the aircraft can still meet the climb
requirements in 14 CFR Part 25.
For all three engines, this is 52.83° 3 = 158.5 lbs/min.
The three engines will burn 158.5° 19 = 3,011.5 pounds
of fuel between the beginning of dumping and touchdown.
6 – 13
3. Determine the amount of fuel needed to dump by
subtracting the amount of fuel burned during the dumping
from the required weight reduction:
28,500.0 lbs required weight reduction
– 3,011.5 lbs fuel burned after start of dumping
25,488.5 lbs fuel to be dumped
4. Determine the time needed to dump this amount of fuel
by dividing the number of pounds of fuel to dump by the
dump rate:
Weight and Balance of Commuter
Category Airplanes
The Beech 1900 is a typical commuter category airplane that
can be configured to carry passengers or cargo. Figure 6-6
shows the loading data of this type of airplane in the passenger
configuration, and Figure 6-14 on Page 6-18 shows the cargo
configuration.
Determining the Loaded Weight and CG
As this airplane is prepared for flight, a manifest like the
 
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