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
2.21.8. Taxi and Runup. The fuel needed for taxiing, engine runup, and acceleration to takeoff speed. It
is usually a predetermined value for each type of aircraft.
2.21.9. Required Ramp Fuel. The amount of fuel required at engine start to complete the mission.
2.21.10. Actual Ramp Fuel. The fuel on board prior to engine start.
2.21.11. Unidentified Extra Fuel. Additional fuel over and above that required by the flight plan. It is
the difference between required ramp fuel and actual ramp fuel.
2.21.12. Burnoff Fuel. Burnoff is the planned amount of fuel to be used after takeoff. This value
subtracted from takeoff gross weight is equal to the approximate aircraft gross weight at landing.
2.22. Range Control Graph. The Range Control Graph portrays planned, minimum, and actual fuel
consumption. A typical range control graph is shown in Figure 2.6. It is used to flight plan fuel
consumption and serves as an in-flight worksheet for comparing actual and planned fuel consumption.
The range control graph can be constructed with information taken from a completed flight plan such as
Figure 2.2 and the applicable fuel planning graph (Figure 2.5). After calculating the required fuel at
checkpoints along the route, the fuel remaining (vertical) is plotted against time remaining (horizontal).
The planned fuel consumption is then plotted on the graph along with the minimum required fuel line.
AFPAM11-216 1 MARCH 2001 79
In-flight fuel readings are taken periodically and plotted on the graph to determine the fuel consumption
in relation to that planned.
Figure 2.6. Typical Range Control Graph.
2.22.1. The planned line is determined by calculating the fuel remaining and time remaining at
predetermined points in the mission and then plotting these points on the graph and connecting them
with a line. The minimum line is determined by adding up all fuel required as a minimum at the
destination (reserve, alternate, approach, etc.) and plotting it on the zero time remaining line. The
difference between the minimum fuel required and the planned fuel on the zero time remaining line is
then plotted below each of the predetermined fuel remaining points on the planned line. The points are
connected with a line that represents the minimum required fuel line. This line is used to determine
whether or not to continue the mission.
2.22.2. In-flight fuel readings are obtained and plotted against time remaining to determine fuel status.
These plotted points are then connected with a dotted line that represents the actual fuel consumption.
The trend of the in-flight fuel readings indicates actual fuel consumption and is used to make mission
decisions with regard to fuel.
2.23. Equal Time Point (ETP). The ETP (Figure 2.7) is that point along the route (normally one with
an extended overwater leg) from which it takes the same amount of time to return to departure (or the
80 AFPAM11-216 1 MARCH 2001
last suitable airfield prior to beginning the overwater leg of the mission) as it would to continue to
destination (or the first suitable airfield for landing). The ETP is not necessarily the midpoint in time
from departure to destination. Its location is somewhere near the midpoint of the route (between suitable
airfields), and it is dependent upon the wind factors.
Figure 2.7. Equal Time Point.
2.23.1. A wind factor (WF) is a headwind or tailwind component, computed at planned altitude between
suitable airfields by comparing the average groundspeed (GS) to the average true airspeed (TAS). To do
this, algebraically subtract the TAS from the GS. A WF with a minus value is a headwind; positive is a
tailwind. When computing ETP, obtain a WF for each half of the route.
2.23.2. Wind factors may play a major role in determining whether or not you can reach your destination.
The overall or Total Wind Factor (TFW) is the average of WF1 and WF2 and is computed using the
formula (WF1 + WF2) divided by 2.
2.23.3. An ETP is computed using the following formula:
2.23.4. Total distance is the distance in NMs from the last suitable airfield to the first suitable airfield,
measured along the route of flight. WF2 and WF1 are wind factors for the second and first halves of the
route segment, respectively. T is the time remaining in minutes from the ETP to the first suitable airfield.
This time can be converted to distance by applying the GS for the second half of the route segment. The
distance can then be measured uptrack and the ETP plotted on the chart. The time should be plotted on
the range control graph with a vertical line that crosses both the planned and minimum lines. If the first
suitable airfield is not the planned landing airfield, then the time should be added between the first
suitable airfield and the landing airfield to determine the ETP.
中国航空网 www.aero.cn
航空翻译 www.aviation.cn
本文链接地址：
F16 Flying Operations AIR NAVIGATION(44)
